[PATCH v8:for-boris 00/30] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[PATCH v8:for-boris 00/30] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[James Morse]

Changes since v7?:
 * Series split to the first 30 patches, requested by Boris.
 * Fixed stale function names, definitions/declartions and typos.
 * Dropped the use of the default ctrlval helper in cache_alloc_hsw_probe()

As ever, changes are noted on each patch.
---
This series renames functions and moves code around. With the
exception of invalid configurations for the configurable-events, there should
be no changes in behaviour caused by this series. It is now possible for
throttle_mode to report 'undefined', but no known platform will do this.

The driving pattern is to make things like struct rdtgroup private to resctrl.
Features like pseudo-lock aren't going to work on arm64, the ability to disable
it at compile time is added.

All this is to allow the filesystem portions of resctrl to be moved to live in /fs/,
which allows resctrl to be supported by other architecture, such as arm64's MPAM.
(What's MPAM? See the cover letter of the first series. [1])

This series is based on v6.14-rc3 and can be retrieved from:
https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/move_to_fs/v8_for_boris

As ever - bugs welcome,
Thanks,

James

[v7] https://lore.kernel.org/lkml/20250228195913.24895-1-james.morse@arm.com
[v6] https://lore.kernel.org/lkml/20250207181823.6378-1-james.morse@arm.com/
[v5] https://lore.kernel.org/r/20241004180347.19985-1-james.morse@arm.com
[v4] https://lore.kernel.org/all/20240802172853.22529-1-james.morse@arm.com/
[v3] https://lore.kernel.org/r/20240614150033.10454-1-james.morse@arm.com
[v2] https://lore.kernel.org/r/20240426150537.8094-1-Dave.Martin@arm.com
[v1] https://lore.kernel.org/r/20240321165106.31602-1-james.morse@arm.com
[1] https://lore.kernel.org/lkml/20201030161120.227225-1-james.morse@arm.com/

James Morse (30):
  x86/resctrl: Fix allocation of cleanest CLOSID on platforms with no
    monitors
  x86/resctrl: Add a helper to avoid reaching into the arch code
    resource list
  x86/resctrl: Remove fflags from struct rdt_resource
  x86/resctrl: Use schema type to determine how to parse schema values
  x86/resctrl: Use schema type to determine the schema format string
  x86/resctrl: Remove data_width and the tabular format
  x86/resctrl: Add max_bw to struct resctrl_membw
  x86/resctrl: Generate default_ctrl instead of sharing it
  x86/resctrl: Add helper for setting CPU default properties
  x86/resctrl: Remove rdtgroup from update_cpu_closid_rmid()
  x86/resctrl: Expose resctrl fs's init function to the rest of the
    kernel
  x86/resctrl: Move rdt_find_domain() to be visible to arch and fs code
  x86/resctrl: Move resctrl types to a separate header
  x86/resctrl: Add an arch helper to reset one resource
  x86/resctrl: Move monitor exit work to a resctrl exit call
  x86/resctrl: Move monitor init work to a resctrl init call
  x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkers
  x86/resctrl: Move the is_mbm_*_enabled() helpers to asm/resctrl.h
  x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC
  x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers
  x86/resctrl: Move mba_mbps_default_event init to filesystem code
  x86/resctrl: Move mbm_cfg_mask to struct rdt_resource
  x86/resctrl: Add resctrl_arch_ prefix to pseudo lock functions
  x86/resctrl: Allow an architecture to disable pseudo lock
  x86/resctrl: Make prefetch_disable_bits belong to the arch code
  x86/resctrl: Make resctrl_arch_pseudo_lock_fn() take a plr
  x86/resctrl: Move RFTYPE flags to be managed by resctrl
  x86/resctrl: Handle throttle_mode for SMBA resources
  x86/resctrl: Move get_config_index() to a header
  x86/resctrl: Move get_{mon,ctrl}_domain_from_cpu() to live with their
    callers

 MAINTAINERS                               |   1 +
 arch/x86/Kconfig                          |   7 +
 arch/x86/include/asm/resctrl.h            |  36 ++-
 arch/x86/kernel/cpu/resctrl/Makefile      |   5 +-
 arch/x86/kernel/cpu/resctrl/core.c        | 181 ++++----------
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  93 ++++---
 arch/x86/kernel/cpu/resctrl/internal.h    | 201 ++++-----------
 arch/x86/kernel/cpu/resctrl/monitor.c     | 119 ++++++---
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c |  55 +++--
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 284 ++++++++++++++++------
 include/linux/resctrl.h                   | 212 ++++++++++++++--
 include/linux/resctrl_types.h             |  54 ++++
 12 files changed, 769 insertions(+), 479 deletions(-)
 create mode 100644 include/linux/resctrl_types.h

-- 
2.39.5

[PATCH v8:for-boris 01/30] x86/resctrl: Fix allocation of cleanest CLOSID on platforms with no monitors

[James Morse]

commit 6eac36bb9eb0 ("x86/resctrl: Allocate the cleanest CLOSID by
searching closid_num_dirty_rmid") added logic that causes resctrl to
search for the CLOSID with the fewest dirty cache lines when creating a
new control group, if requested by the arch code. This depends on the
values read from the llc_occupancy counters. The logic is applicable to
architectures where the CLOSID effectively forms part of the monitoring
identifier and so do not allow complete freedom to choose an unused
monitoring identifier for a given CLOSID.

This support missed that some platforms may not have these counters.
This causes a NULL pointer dereference when creating a new control
group as the array was not allocated by dom_data_init().

As this feature isn't necessary on platforms that don't have cache
occupancy monitors, add this to the check that occurs when a new
control group is allocated.

Fixes: 6eac36bb9eb0 ("x86/resctrl: Allocate the cleanest CLOSID by searching closid_num_dirty_rmid")
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
The existing code is not selected by any upstream platform, it makes
no sense to backport this patch to stable.

Changes since v1:
 * [Commit message only] Reword the first paragraph to make it clear
   that the issue being fixed wasn't directly associated with addition
   of a Kconfig option.  (Actually, the option is not in Kconfig yet,
   and gets added later in this series.)
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 6419e04d8a7b..04b653d613e8 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -157,7 +157,8 @@ static int closid_alloc(void)
 
 	lockdep_assert_held(&rdtgroup_mutex);
 
-	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) {
+	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID) &&
+	    is_llc_occupancy_enabled()) {
 		cleanest_closid = resctrl_find_cleanest_closid();
 		if (cleanest_closid < 0)
 			return cleanest_closid;
-- 
2.39.5

[PATCH v8:for-boris 02/30] x86/resctrl: Add a helper to avoid reaching into the arch code resource list

[James Morse]

Resctrl occasionally wants to know something about a specific resource,
in these cases it reaches into the arch code's rdt_resources_all[]
array.

Once the filesystem parts of resctrl are moved to /fs/, this means it
will need visibility of the architecture specific struct
rdt_hw_resource definition, and the array of all resources.  All
architectures would also need a r_resctrl member in this struct.

Instead, abstract this via a helper to allow architectures to do
different things here. Move the level enum to the resctrl header and
add a helper to retrieve the struct rdt_resource by 'rid'.

resctrl_arch_get_resource() should not return NULL for any value in
the enum, it may instead return a dummy resource that is
!alloc_enabled && !mon_enabled.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Change since v5:
 * Ensure rdt_resources_all[] is always padded to RDT_NUM_RESOURCES

Changes since v1:
 * Backed out non-functional renaming of "r" to "l3" in rdt_get_tree(),
   and unhoisted the assignment of r (as now is) back into the if ()
   where it started out.  There seem to be no uses of this variable
   outside this if().
 * [Commit message only] Typo fix:
   s/resctrl_hw_resource/rdt_hw_resource/g
---
 arch/x86/kernel/cpu/resctrl/core.c        | 12 ++++++++++--
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  2 +-
 arch/x86/kernel/cpu/resctrl/internal.h    | 10 ----------
 arch/x86/kernel/cpu/resctrl/monitor.c     |  8 ++++----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 14 +++++++-------
 include/linux/resctrl.h                   | 17 +++++++++++++++++
 6 files changed, 39 insertions(+), 24 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 3d1735ed8d1f..12b41316d8f7 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -62,7 +62,7 @@ static void mba_wrmsr_amd(struct msr_param *m);
 #define ctrl_domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].r_resctrl.ctrl_domains)
 #define mon_domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].r_resctrl.mon_domains)
 
-struct rdt_hw_resource rdt_resources_all[] = {
+struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 	[RDT_RESOURCE_L3] =
 	{
 		.r_resctrl = {
@@ -127,6 +127,14 @@ u32 resctrl_arch_system_num_rmid_idx(void)
 	return r->num_rmid;
 }
 
+struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l)
+{
+	if (l >= RDT_NUM_RESOURCES)
+		return NULL;
+
+	return &rdt_resources_all[l].r_resctrl;
+}
+
 /*
  * cache_alloc_hsw_probe() - Have to probe for Intel haswell server CPUs
  * as they do not have CPUID enumeration support for Cache allocation.
@@ -174,7 +182,7 @@ static inline void cache_alloc_hsw_probe(void)
 bool is_mba_sc(struct rdt_resource *r)
 {
 	if (!r)
-		return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.mba_sc;
+		r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 
 	/*
 	 * The software controller support is only applicable to MBA resource.
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 536351159cc2..4af27ef5a8a1 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -649,7 +649,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 	resid = md.u.rid;
 	domid = md.u.domid;
 	evtid = md.u.evtid;
-	r = &rdt_resources_all[resid].r_resctrl;
+	r = resctrl_arch_get_resource(resid);
 
 	if (md.u.sum) {
 		/*
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 20c898f09b7e..75252a7e1ebc 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -512,16 +512,6 @@ extern struct rdtgroup rdtgroup_default;
 extern struct dentry *debugfs_resctrl;
 extern enum resctrl_event_id mba_mbps_default_event;
 
-enum resctrl_res_level {
-	RDT_RESOURCE_L3,
-	RDT_RESOURCE_L2,
-	RDT_RESOURCE_MBA,
-	RDT_RESOURCE_SMBA,
-
-	/* Must be the last */
-	RDT_NUM_RESOURCES,
-};
-
 static inline struct rdt_resource *resctrl_inc(struct rdt_resource *res)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(res);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 94a1d9780461..58b5b21349a8 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -365,7 +365,7 @@ static void limbo_release_entry(struct rmid_entry *entry)
  */
 void __check_limbo(struct rdt_mon_domain *d, bool force_free)
 {
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
 	struct rmid_entry *entry;
 	u32 idx, cur_idx = 1;
@@ -521,7 +521,7 @@ int alloc_rmid(u32 closid)
 
 static void add_rmid_to_limbo(struct rmid_entry *entry)
 {
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	struct rdt_mon_domain *d;
 	u32 idx;
 
@@ -761,7 +761,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_mon_domain *dom_mbm)
 	struct rdtgroup *entry;
 	u32 cur_bw, user_bw;
 
-	r_mba = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+	r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 	evt_id = rgrp->mba_mbps_event;
 
 	closid = rgrp->closid;
@@ -925,7 +925,7 @@ void mbm_handle_overflow(struct work_struct *work)
 	if (!resctrl_mounted || !resctrl_arch_mon_capable())
 		goto out_unlock;
 
-	r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	d = container_of(work, struct rdt_mon_domain, mbm_over.work);
 
 	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 04b653d613e8..45093b9e8e63 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2256,7 +2256,7 @@ static void l2_qos_cfg_update(void *arg)
 
 static inline bool is_mba_linear(void)
 {
-	return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.delay_linear;
+	return resctrl_arch_get_resource(RDT_RESOURCE_MBA)->membw.delay_linear;
 }
 
 static int set_cache_qos_cfg(int level, bool enable)
@@ -2346,8 +2346,8 @@ static void mba_sc_domain_destroy(struct rdt_resource *r,
  */
 static bool supports_mba_mbps(void)
 {
-	struct rdt_resource *rmbm = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+	struct rdt_resource *rmbm = resctrl_arch_get_resource(RDT_RESOURCE_L3);
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 
 	return (is_mbm_enabled() &&
 		r->alloc_capable && is_mba_linear() &&
@@ -2360,7 +2360,7 @@ static bool supports_mba_mbps(void)
  */
 static int set_mba_sc(bool mba_sc)
 {
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 	u32 num_closid = resctrl_arch_get_num_closid(r);
 	struct rdt_ctrl_domain *d;
 	unsigned long fflags;
@@ -2714,7 +2714,7 @@ static int rdt_get_tree(struct fs_context *fc)
 		resctrl_mounted = true;
 
 	if (is_mbm_enabled()) {
-		r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+		r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 		list_for_each_entry(dom, &r->mon_domains, hdr.list)
 			mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL,
 						   RESCTRL_PICK_ANY_CPU);
@@ -3951,7 +3951,7 @@ static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf)
 	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2))
 		seq_puts(seq, ",cdpl2");
 
-	if (is_mba_sc(&rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl))
+	if (is_mba_sc(resctrl_arch_get_resource(RDT_RESOURCE_MBA)))
 		seq_puts(seq, ",mba_MBps");
 
 	if (resctrl_debug)
@@ -4151,7 +4151,7 @@ static void clear_childcpus(struct rdtgroup *r, unsigned int cpu)
 
 void resctrl_offline_cpu(unsigned int cpu)
 {
-	struct rdt_resource *l3 = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rdt_resource *l3 = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	struct rdt_mon_domain *d;
 	struct rdtgroup *rdtgrp;
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index d94abba1c716..37279e2a89da 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -37,6 +37,16 @@ enum resctrl_conf_type {
 	CDP_DATA,
 };
 
+enum resctrl_res_level {
+	RDT_RESOURCE_L3,
+	RDT_RESOURCE_L2,
+	RDT_RESOURCE_MBA,
+	RDT_RESOURCE_SMBA,
+
+	/* Must be the last */
+	RDT_NUM_RESOURCES,
+};
+
 #define CDP_NUM_TYPES	(CDP_DATA + 1)
 
 /*
@@ -226,6 +236,13 @@ struct rdt_resource {
 	bool			cdp_capable;
 };
 
+/*
+ * Get the resource that exists at this level. If the level is not supported
+ * a dummy/not-capable resource can be returned. Levels >= RDT_NUM_RESOURCES
+ * will return NULL.
+ */
+struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l);
+
 /**
  * struct resctrl_schema - configuration abilities of a resource presented to
  *			   user-space
-- 
2.39.5

[PATCH v8:for-boris 03/30] x86/resctrl: Remove fflags from struct rdt_resource

[James Morse]

The resctrl arch code specifies whether a resource controls a cache or
memory using the fflags field. This field is then used by resctrl to
determine which files should be exposed in the filesystem.

Allowing the architecture to pick this value means the RFTYPE_
flags have to be in a shared header, and allows an architecture
to create a combination that resctrl does not support.

Remove the fflags field, and pick the value based on the resource
id.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Made fflags_from_resource() return an unsigned long.
 * Removed a space.

Changes since v4:
 * Removed an extra space
 * Fixed a typo
---
 arch/x86/kernel/cpu/resctrl/core.c     |  4 ----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 18 ++++++++++++++++--
 include/linux/resctrl.h                |  2 --
 3 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 12b41316d8f7..8ef2e449b465 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -74,7 +74,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.mon_domains		= mon_domain_init(RDT_RESOURCE_L3),
 			.parse_ctrlval		= parse_cbm,
 			.format_str		= "%d=%0*x",
-			.fflags			= RFTYPE_RES_CACHE,
 		},
 		.msr_base		= MSR_IA32_L3_CBM_BASE,
 		.msr_update		= cat_wrmsr,
@@ -88,7 +87,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L2),
 			.parse_ctrlval		= parse_cbm,
 			.format_str		= "%d=%0*x",
-			.fflags			= RFTYPE_RES_CACHE,
 		},
 		.msr_base		= MSR_IA32_L2_CBM_BASE,
 		.msr_update		= cat_wrmsr,
@@ -102,7 +100,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_MBA),
 			.parse_ctrlval		= parse_bw,
 			.format_str		= "%d=%*u",
-			.fflags			= RFTYPE_RES_MB,
 		},
 	},
 	[RDT_RESOURCE_SMBA] =
@@ -114,7 +111,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
 			.parse_ctrlval		= parse_bw,
 			.format_str		= "%d=%*u",
-			.fflags			= RFTYPE_RES_MB,
 		},
 	},
 };
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 45093b9e8e63..3391ac8ecb2d 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2165,6 +2165,20 @@ static int rdtgroup_mkdir_info_resdir(void *priv, char *name,
 	return ret;
 }
 
+static unsigned long fflags_from_resource(struct rdt_resource *r)
+{
+	switch (r->rid) {
+	case RDT_RESOURCE_L3:
+	case RDT_RESOURCE_L2:
+		return RFTYPE_RES_CACHE;
+	case RDT_RESOURCE_MBA:
+	case RDT_RESOURCE_SMBA:
+		return RFTYPE_RES_MB;
+	}
+
+	return WARN_ON_ONCE(1);
+}
+
 static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
 {
 	struct resctrl_schema *s;
@@ -2185,14 +2199,14 @@ static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
 	/* loop over enabled controls, these are all alloc_capable */
 	list_for_each_entry(s, &resctrl_schema_all, list) {
 		r = s->res;
-		fflags = r->fflags | RFTYPE_CTRL_INFO;
+		fflags = fflags_from_resource(r) | RFTYPE_CTRL_INFO;
 		ret = rdtgroup_mkdir_info_resdir(s, s->name, fflags);
 		if (ret)
 			goto out_destroy;
 	}
 
 	for_each_mon_capable_rdt_resource(r) {
-		fflags = r->fflags | RFTYPE_MON_INFO;
+		fflags = fflags_from_resource(r) | RFTYPE_MON_INFO;
 		sprintf(name, "%s_MON", r->name);
 		ret = rdtgroup_mkdir_info_resdir(r, name, fflags);
 		if (ret)
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 37279e2a89da..496ddcaa4ecf 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -210,7 +210,6 @@ enum resctrl_scope {
  * @format_str:		Per resource format string to show domain value
  * @parse_ctrlval:	Per resource function pointer to parse control values
  * @evt_list:		List of monitoring events
- * @fflags:		flags to choose base and info files
  * @cdp_capable:	Is the CDP feature available on this resource
  */
 struct rdt_resource {
@@ -232,7 +231,6 @@ struct rdt_resource {
 						 struct resctrl_schema *s,
 						 struct rdt_ctrl_domain *d);
 	struct list_head	evt_list;
-	unsigned long		fflags;
 	bool			cdp_capable;
 };
 
-- 
2.39.5

[PATCH v8:for-boris 04/30] x86/resctrl: Use schema type to determine how to parse schema values

[James Morse]

Resctrl's architecture code gets to specify a function pointer that is
used when parsing schema entries. This is expected to be one of two
helpers from the filesystem code.

Setting this function pointer allows the architecture code to change
the ABI resctrl presents to user-space, and forces resctrl to expose
these helpers.

Instead, add a schema format enum to choose which schema parser to
use. This allows the helpers to be made static and the structs used
for passing arguments moved out of shared headers.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Change since v6:
 * Added a full stop.

Changes since v5:
 * Merged the contents of get_parser() with its only caller.
 * Removed the description of what the range schema is used for.
 * Waggled some whitespace.

Changes since v4:
 * Creation of the enum moves into this patch - review tags not picked up.
 * Removed some whitespace.

Changes since v3:
 * Removed a spurious semicolon

Changes since v2:
 * This patch is new
---
 arch/x86/kernel/cpu/resctrl/core.c        |  8 +++---
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 32 +++++++++++++++++++----
 arch/x86/kernel/cpu/resctrl/internal.h    | 10 -------
 include/linux/resctrl.h                   | 17 ++++++++----
 4 files changed, 43 insertions(+), 24 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 8ef2e449b465..e9fe129a02f8 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -72,7 +72,7 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.mon_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L3),
 			.mon_domains		= mon_domain_init(RDT_RESOURCE_L3),
-			.parse_ctrlval		= parse_cbm,
+			.schema_fmt		= RESCTRL_SCHEMA_BITMAP,
 			.format_str		= "%d=%0*x",
 		},
 		.msr_base		= MSR_IA32_L3_CBM_BASE,
@@ -85,7 +85,7 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.name			= "L2",
 			.ctrl_scope		= RESCTRL_L2_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L2),
-			.parse_ctrlval		= parse_cbm,
+			.schema_fmt		= RESCTRL_SCHEMA_BITMAP,
 			.format_str		= "%d=%0*x",
 		},
 		.msr_base		= MSR_IA32_L2_CBM_BASE,
@@ -98,7 +98,7 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.name			= "MB",
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_MBA),
-			.parse_ctrlval		= parse_bw,
+			.schema_fmt		= RESCTRL_SCHEMA_RANGE,
 			.format_str		= "%d=%*u",
 		},
 	},
@@ -109,7 +109,7 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.name			= "SMBA",
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
-			.parse_ctrlval		= parse_bw,
+			.schema_fmt		= RESCTRL_SCHEMA_RANGE,
 			.format_str		= "%d=%*u",
 		},
 	},
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 4af27ef5a8a1..f4334f437ffc 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -23,6 +23,15 @@
 
 #include "internal.h"
 
+struct rdt_parse_data {
+	struct rdtgroup		*rdtgrp;
+	char			*buf;
+};
+
+typedef int (ctrlval_parser_t)(struct rdt_parse_data *data,
+			       struct resctrl_schema *s,
+			       struct rdt_ctrl_domain *d);
+
 /*
  * Check whether MBA bandwidth percentage value is correct. The value is
  * checked against the minimum and max bandwidth values specified by the
@@ -64,8 +73,8 @@ static bool bw_validate(char *buf, u32 *data, struct rdt_resource *r)
 	return true;
 }
 
-int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
-	     struct rdt_ctrl_domain *d)
+static int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
+		    struct rdt_ctrl_domain *d)
 {
 	struct resctrl_staged_config *cfg;
 	u32 closid = data->rdtgrp->closid;
@@ -143,8 +152,8 @@ static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
  * Read one cache bit mask (hex). Check that it is valid for the current
  * resource type.
  */
-int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
-	      struct rdt_ctrl_domain *d)
+static int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
+		     struct rdt_ctrl_domain *d)
 {
 	struct rdtgroup *rdtgrp = data->rdtgrp;
 	struct resctrl_staged_config *cfg;
@@ -210,6 +219,7 @@ static int parse_line(char *line, struct resctrl_schema *s,
 		      struct rdtgroup *rdtgrp)
 {
 	enum resctrl_conf_type t = s->conf_type;
+	ctrlval_parser_t *parse_ctrlval = NULL;
 	struct resctrl_staged_config *cfg;
 	struct rdt_resource *r = s->res;
 	struct rdt_parse_data data;
@@ -220,6 +230,18 @@ static int parse_line(char *line, struct resctrl_schema *s,
 	/* Walking r->domains, ensure it can't race with cpuhp */
 	lockdep_assert_cpus_held();
 
+	switch (r->schema_fmt) {
+	case RESCTRL_SCHEMA_BITMAP:
+		parse_ctrlval = &parse_cbm;
+		break;
+	case RESCTRL_SCHEMA_RANGE:
+		parse_ctrlval = &parse_bw;
+		break;
+	}
+
+	if (WARN_ON_ONCE(!parse_ctrlval))
+		return -EINVAL;
+
 	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
 	    (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)) {
 		rdt_last_cmd_puts("Cannot pseudo-lock MBA resource\n");
@@ -240,7 +262,7 @@ static int parse_line(char *line, struct resctrl_schema *s,
 		if (d->hdr.id == dom_id) {
 			data.buf = dom;
 			data.rdtgrp = rdtgrp;
-			if (r->parse_ctrlval(&data, s, d))
+			if (parse_ctrlval(&data, s, d))
 				return -EINVAL;
 			if (rdtgrp->mode ==  RDT_MODE_PSEUDO_LOCKSETUP) {
 				cfg = &d->staged_config[t];
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 75252a7e1ebc..b5543bd506c3 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -459,11 +459,6 @@ static inline bool is_mbm_event(int e)
 		e <= QOS_L3_MBM_LOCAL_EVENT_ID);
 }
 
-struct rdt_parse_data {
-	struct rdtgroup		*rdtgrp;
-	char			*buf;
-};
-
 /**
  * struct rdt_hw_resource - arch private attributes of a resctrl resource
  * @r_resctrl:		Attributes of the resource used directly by resctrl.
@@ -500,11 +495,6 @@ static inline struct rdt_hw_resource *resctrl_to_arch_res(struct rdt_resource *r
 	return container_of(r, struct rdt_hw_resource, r_resctrl);
 }
 
-int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
-	      struct rdt_ctrl_domain *d);
-int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
-	     struct rdt_ctrl_domain *d);
-
 extern struct mutex rdtgroup_mutex;
 
 extern struct rdt_hw_resource rdt_resources_all[];
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 496ddcaa4ecf..3e1a41356b2a 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -183,7 +183,6 @@ struct resctrl_membw {
 	u32				*mb_map;
 };
 
-struct rdt_parse_data;
 struct resctrl_schema;
 
 enum resctrl_scope {
@@ -192,6 +191,16 @@ enum resctrl_scope {
 	RESCTRL_L3_NODE,
 };
 
+/**
+ * enum resctrl_schema_fmt - The format user-space provides for a schema.
+ * @RESCTRL_SCHEMA_BITMAP:	The schema is a bitmap in hex.
+ * @RESCTRL_SCHEMA_RANGE:	The schema is a decimal number.
+ */
+enum resctrl_schema_fmt {
+	RESCTRL_SCHEMA_BITMAP,
+	RESCTRL_SCHEMA_RANGE,
+};
+
 /**
  * struct rdt_resource - attributes of a resctrl resource
  * @rid:		The index of the resource
@@ -208,7 +217,7 @@ enum resctrl_scope {
  * @data_width:		Character width of data when displaying
  * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
  * @format_str:		Per resource format string to show domain value
- * @parse_ctrlval:	Per resource function pointer to parse control values
+ * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
  * @cdp_capable:	Is the CDP feature available on this resource
  */
@@ -227,9 +236,7 @@ struct rdt_resource {
 	int			data_width;
 	u32			default_ctrl;
 	const char		*format_str;
-	int			(*parse_ctrlval)(struct rdt_parse_data *data,
-						 struct resctrl_schema *s,
-						 struct rdt_ctrl_domain *d);
+	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
 	bool			cdp_capable;
 };
-- 
2.39.5

[PATCH v8:for-boris 05/30] x86/resctrl: Use schema type to determine the schema format string

[James Morse]

Resctrl's architecture code gets to specify a format string that is
used when printing schema entries. This is expected to be one of two
values that the filesystem code supports.

Setting this format string allows the architecture code to change
the ABI resctrl presents to user-space.

Instead, use the schema format enum to choose which format string to
use.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Added runtime check for resource schema_format being junk.

Change since v4:
 * Added a stop to a struct comment.

Changes since v2:
 * This patch is new.
---
 arch/x86/kernel/cpu/resctrl/core.c        |  4 ----
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 14 ++++++++++++++
 include/linux/resctrl.h                   |  4 ++--
 4 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index e9fe129a02f8..542503a8c953 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -73,7 +73,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L3),
 			.mon_domains		= mon_domain_init(RDT_RESOURCE_L3),
 			.schema_fmt		= RESCTRL_SCHEMA_BITMAP,
-			.format_str		= "%d=%0*x",
 		},
 		.msr_base		= MSR_IA32_L3_CBM_BASE,
 		.msr_update		= cat_wrmsr,
@@ -86,7 +85,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_scope		= RESCTRL_L2_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L2),
 			.schema_fmt		= RESCTRL_SCHEMA_BITMAP,
-			.format_str		= "%d=%0*x",
 		},
 		.msr_base		= MSR_IA32_L2_CBM_BASE,
 		.msr_update		= cat_wrmsr,
@@ -99,7 +97,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_MBA),
 			.schema_fmt		= RESCTRL_SCHEMA_RANGE,
-			.format_str		= "%d=%*u",
 		},
 	},
 	[RDT_RESOURCE_SMBA] =
@@ -110,7 +107,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
 			.schema_fmt		= RESCTRL_SCHEMA_RANGE,
-			.format_str		= "%d=%*u",
 		},
 	},
 };
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index f4334f437ffc..c763cb4fb1a8 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -487,7 +487,7 @@ static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int clo
 			ctrl_val = resctrl_arch_get_config(r, dom, closid,
 							   schema->conf_type);
 
-		seq_printf(s, r->format_str, dom->hdr.id, max_data_width,
+		seq_printf(s, schema->fmt_str, dom->hdr.id, max_data_width,
 			   ctrl_val);
 		sep = true;
 	}
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 3391ac8ecb2d..e7862d0936c9 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2611,6 +2611,20 @@ static int schemata_list_add(struct rdt_resource *r, enum resctrl_conf_type type
 	if (cl > max_name_width)
 		max_name_width = cl;
 
+	switch (r->schema_fmt) {
+	case RESCTRL_SCHEMA_BITMAP:
+		s->fmt_str = "%d=%0*x";
+		break;
+	case RESCTRL_SCHEMA_RANGE:
+		s->fmt_str = "%d=%0*u";
+		break;
+	}
+
+	if (WARN_ON_ONCE(!s->fmt_str)) {
+		kfree(s);
+		return -EINVAL;
+	}
+
 	INIT_LIST_HEAD(&s->list);
 	list_add(&s->list, &resctrl_schema_all);
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 3e1a41356b2a..736b9a9a9464 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -216,7 +216,6 @@ enum resctrl_schema_fmt {
  * @name:		Name to use in "schemata" file.
  * @data_width:		Character width of data when displaying
  * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
- * @format_str:		Per resource format string to show domain value
  * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
  * @cdp_capable:	Is the CDP feature available on this resource
@@ -235,7 +234,6 @@ struct rdt_resource {
 	char			*name;
 	int			data_width;
 	u32			default_ctrl;
-	const char		*format_str;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
 	bool			cdp_capable;
@@ -253,6 +251,7 @@ struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l);
  *			   user-space
  * @list:	Member of resctrl_schema_all.
  * @name:	The name to use in the "schemata" file.
+ * @fmt_str:	Format string to show domain value.
  * @conf_type:	Whether this schema is specific to code/data.
  * @res:	The resource structure exported by the architecture to describe
  *		the hardware that is configured by this schema.
@@ -263,6 +262,7 @@ struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l);
 struct resctrl_schema {
 	struct list_head		list;
 	char				name[8];
+	const char			*fmt_str;
 	enum resctrl_conf_type		conf_type;
 	struct rdt_resource		*res;
 	u32				num_closid;
-- 
2.39.5

[PATCH v8:for-boris 06/30] x86/resctrl: Remove data_width and the tabular format

[James Morse]

The resctrl architecture code provides a data_width for the controls of
each resource. This is used to zero pad all control values in the schemata
file so they appear in columns. The same is done with the resource names
to complete the visual effect. e.g.
| SMBA:0=2048
|   L3:0=00ff

AMD platforms discover their maximum bandwidth for the MB resource from
firmware, but hard-code the data_width to 4. If the maximum bandwidth
requires more digits - the tabular format is silently broken.
This is also broken when the mba_MBps mount option is used as the
field width isn't updated. If new schema are added resctrl will need
to be able to determine the maximum width. The benefit of this
pretty-printing is questionable.

Instead of handling runtime discovery of the data_width for AMD platforms,
remove the feature. These fields are always zero padded so should be
harmless to remove if the whole field has been treated as a number.
In the above example, this would now look like this:
| SMBA:0=2048
|   L3:0=ff

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
 arch/x86/kernel/cpu/resctrl/core.c        | 26 -----------------------
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  3 +--
 arch/x86/kernel/cpu/resctrl/internal.h    |  2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 10 +++++++--
 include/linux/resctrl.h                   |  2 --
 5 files changed, 10 insertions(+), 33 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 542503a8c953..754fb65565ec 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -43,12 +43,6 @@ static DEFINE_MUTEX(domain_list_lock);
  */
 DEFINE_PER_CPU(struct resctrl_pqr_state, pqr_state);
 
-/*
- * Used to store the max resource name width and max resource data width
- * to display the schemata in a tabular format
- */
-int max_name_width, max_data_width;
-
 /*
  * Global boolean for rdt_alloc which is true if any
  * resource allocation is enabled.
@@ -228,7 +222,6 @@ static __init bool __get_mem_config_intel(struct rdt_resource *r)
 			return false;
 		r->membw.arch_needs_linear = false;
 	}
-	r->data_width = 3;
 
 	if (boot_cpu_has(X86_FEATURE_PER_THREAD_MBA))
 		r->membw.throttle_mode = THREAD_THROTTLE_PER_THREAD;
@@ -269,8 +262,6 @@ static __init bool __rdt_get_mem_config_amd(struct rdt_resource *r)
 	r->membw.throttle_mode = THREAD_THROTTLE_UNDEFINED;
 	r->membw.min_bw = 0;
 	r->membw.bw_gran = 1;
-	/* Max value is 2048, Data width should be 4 in decimal */
-	r->data_width = 4;
 
 	r->alloc_capable = true;
 
@@ -290,7 +281,6 @@ static void rdt_get_cache_alloc_cfg(int idx, struct rdt_resource *r)
 	r->cache.cbm_len = eax.split.cbm_len + 1;
 	r->default_ctrl = BIT_MASK(eax.split.cbm_len + 1) - 1;
 	r->cache.shareable_bits = ebx & r->default_ctrl;
-	r->data_width = (r->cache.cbm_len + 3) / 4;
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
 		r->cache.arch_has_sparse_bitmasks = ecx.split.noncont;
 	r->alloc_capable = true;
@@ -786,20 +776,6 @@ static int resctrl_arch_offline_cpu(unsigned int cpu)
 	return 0;
 }
 
-/*
- * Choose a width for the resource name and resource data based on the
- * resource that has widest name and cbm.
- */
-static __init void rdt_init_padding(void)
-{
-	struct rdt_resource *r;
-
-	for_each_alloc_capable_rdt_resource(r) {
-		if (r->data_width > max_data_width)
-			max_data_width = r->data_width;
-	}
-}
-
 enum {
 	RDT_FLAG_CMT,
 	RDT_FLAG_MBM_TOTAL,
@@ -1102,8 +1078,6 @@ static int __init resctrl_late_init(void)
 	if (!get_rdt_resources())
 		return -ENODEV;
 
-	rdt_init_padding();
-
 	state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
 				  "x86/resctrl/cat:online:",
 				  resctrl_arch_online_cpu,
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index c763cb4fb1a8..59610b209b4e 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -487,8 +487,7 @@ static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int clo
 			ctrl_val = resctrl_arch_get_config(r, dom, closid,
 							   schema->conf_type);
 
-		seq_printf(s, schema->fmt_str, dom->hdr.id, max_data_width,
-			   ctrl_val);
+		seq_printf(s, schema->fmt_str, dom->hdr.id, ctrl_val);
 		sep = true;
 	}
 	seq_puts(s, "\n");
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index b5543bd506c3..f975cd6cfe61 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -326,7 +326,7 @@ struct rdtgroup {
 /* List of all resource groups */
 extern struct list_head rdt_all_groups;
 
-extern int max_name_width, max_data_width;
+extern int max_name_width;
 
 int __init rdtgroup_init(void);
 void __exit rdtgroup_exit(void);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index e7862d0936c9..1e0bae1a9d95 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -57,6 +57,12 @@ static struct kernfs_node *kn_mongrp;
 /* Kernel fs node for "mon_data" directory under root */
 static struct kernfs_node *kn_mondata;
 
+/*
+ * Used to store the max resource name width to display the schemata names in
+ * a tabular format.
+ */
+int max_name_width;
+
 static struct seq_buf last_cmd_status;
 static char last_cmd_status_buf[512];
 
@@ -2613,10 +2619,10 @@ static int schemata_list_add(struct rdt_resource *r, enum resctrl_conf_type type
 
 	switch (r->schema_fmt) {
 	case RESCTRL_SCHEMA_BITMAP:
-		s->fmt_str = "%d=%0*x";
+		s->fmt_str = "%d=%x";
 		break;
 	case RESCTRL_SCHEMA_RANGE:
-		s->fmt_str = "%d=%0*u";
+		s->fmt_str = "%d=%u";
 		break;
 	}
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 736b9a9a9464..e1a982adef45 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -214,7 +214,6 @@ enum resctrl_schema_fmt {
  * @ctrl_domains:	RCU list of all control domains for this resource
  * @mon_domains:	RCU list of all monitor domains for this resource
  * @name:		Name to use in "schemata" file.
- * @data_width:		Character width of data when displaying
  * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
  * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
@@ -232,7 +231,6 @@ struct rdt_resource {
 	struct list_head	ctrl_domains;
 	struct list_head	mon_domains;
 	char			*name;
-	int			data_width;
 	u32			default_ctrl;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
-- 
2.39.5

[PATCH v8:for-boris 07/30] x86/resctrl: Add max_bw to struct resctrl_membw

[James Morse]

__rdt_get_mem_config_amd() and __get_mem_config_intel() both use
the default_ctrl property as a maximum value. This is because the
MBA schema works differently between these platforms. Doing this
complicates determining whether the default_ctrl property belongs
to the arch code, or can be derived from the schema format.

Deriving the maximum or default value from the schema format would
avoid the architecture code having to tell resctrl such obvious
things as the maximum percentage is 100, and the maximum bitmap
is all ones.

Maximum bandwidth is always going to vary per platform. Add
max_bw as a special case. This is currently used for the maximum
MBA percentage on Intel platforms, but can be removed from the
architecture code if 'percentage' becomes a schema format resctrl
supports directly.

This value isn't needed for other schema formats.

This will allow the default_ctrl to be generated from the schema
properties when it is needed.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Removed redundant setting of schema_fmt on AMD platforms.
 * Fixed off by one in cbm_validate().

Changes since v2:
 * This patch is new.
---
 arch/x86/kernel/cpu/resctrl/core.c        | 2 ++
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 4 ++--
 include/linux/resctrl.h                   | 2 ++
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 754fb65565ec..4504a12efc97 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -212,6 +212,7 @@ static __init bool __get_mem_config_intel(struct rdt_resource *r)
 	hw_res->num_closid = edx.split.cos_max + 1;
 	max_delay = eax.split.max_delay + 1;
 	r->default_ctrl = MAX_MBA_BW;
+	r->membw.max_bw = MAX_MBA_BW;
 	r->membw.arch_needs_linear = true;
 	if (ecx & MBA_IS_LINEAR) {
 		r->membw.delay_linear = true;
@@ -250,6 +251,7 @@ static __init bool __rdt_get_mem_config_amd(struct rdt_resource *r)
 	cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx);
 	hw_res->num_closid = edx + 1;
 	r->default_ctrl = 1 << eax;
+	r->membw.max_bw = 1 << eax;
 
 	/* AMD does not use delay */
 	r->membw.delay_linear = false;
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 59610b209b4e..23a01eaebd58 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -63,9 +63,9 @@ static bool bw_validate(char *buf, u32 *data, struct rdt_resource *r)
 		return true;
 	}
 
-	if (bw < r->membw.min_bw || bw > r->default_ctrl) {
+	if (bw < r->membw.min_bw || bw > r->membw.max_bw) {
 		rdt_last_cmd_printf("MB value %u out of range [%d,%d]\n",
-				    bw, r->membw.min_bw, r->default_ctrl);
+				    bw, r->membw.min_bw, r->membw.max_bw);
 		return false;
 	}
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index e1a982adef45..465f3cf8c4bc 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -165,6 +165,7 @@ enum membw_throttle_mode {
 /**
  * struct resctrl_membw - Memory bandwidth allocation related data
  * @min_bw:		Minimum memory bandwidth percentage user can request
+ * @max_bw:		Maximum memory bandwidth value, used as the reset value
  * @bw_gran:		Granularity at which the memory bandwidth is allocated
  * @delay_linear:	True if memory B/W delay is in linear scale
  * @arch_needs_linear:	True if we can't configure non-linear resources
@@ -175,6 +176,7 @@ enum membw_throttle_mode {
  */
 struct resctrl_membw {
 	u32				min_bw;
+	u32				max_bw;
 	u32				bw_gran;
 	u32				delay_linear;
 	bool				arch_needs_linear;
-- 
2.39.5

[PATCH v8:for-boris 08/30] x86/resctrl: Generate default_ctrl instead of sharing it

[James Morse]

The struct rdt_resource default_ctrl is used by both the architecture
code for resetting the hardware controls, and sometimes by the
filesystem code as the default value for the schema, unless the
bandwidth software controller is in use.

Having the default exposed by the architecture code causes unnecessary
duplication for each architecture as the default value must be specified,
but can be derived from other schema properties. Now that the
maximum bandwidth is explicitly described, resctrl can derive the default
value from the schema format and the other resource properties.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v7:
 * Dropped the hunk in cache_alloc_hsw_probe() and left it open-coded for
   readability.

Changes since v6:
 * Return MBA_BW_MAX from delay_bw_map() for improved readability.
 * Generate the bitmap directly in rdt_get_cache_alloc_cfg() to make it
   clear shareable_bits is being generated correctly.

Changes since v5:
 * Rewrote commit message.

Changes since v2:
 * This patch is new.
---
 arch/x86/kernel/cpu/resctrl/core.c        | 13 +++++--------
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  5 +++--
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    |  6 +++---
 include/linux/resctrl.h                   | 19 +++++++++++++++++--
 4 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 4504a12efc97..d001ca43b53d 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -155,7 +155,6 @@ static inline void cache_alloc_hsw_probe(void)
 		return;
 
 	hw_res->num_closid = 4;
-	r->default_ctrl = max_cbm;
 	r->cache.cbm_len = 20;
 	r->cache.shareable_bits = 0xc0000;
 	r->cache.min_cbm_bits = 2;
@@ -211,7 +210,6 @@ static __init bool __get_mem_config_intel(struct rdt_resource *r)
 	cpuid_count(0x00000010, 3, &eax.full, &ebx, &ecx, &edx.full);
 	hw_res->num_closid = edx.split.cos_max + 1;
 	max_delay = eax.split.max_delay + 1;
-	r->default_ctrl = MAX_MBA_BW;
 	r->membw.max_bw = MAX_MBA_BW;
 	r->membw.arch_needs_linear = true;
 	if (ecx & MBA_IS_LINEAR) {
@@ -250,7 +248,6 @@ static __init bool __rdt_get_mem_config_amd(struct rdt_resource *r)
 
 	cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx);
 	hw_res->num_closid = edx + 1;
-	r->default_ctrl = 1 << eax;
 	r->membw.max_bw = 1 << eax;
 
 	/* AMD does not use delay */
@@ -276,13 +273,13 @@ static void rdt_get_cache_alloc_cfg(int idx, struct rdt_resource *r)
 	union cpuid_0x10_1_eax eax;
 	union cpuid_0x10_x_ecx ecx;
 	union cpuid_0x10_x_edx edx;
-	u32 ebx;
+	u32 ebx, default_ctrl;
 
 	cpuid_count(0x00000010, idx, &eax.full, &ebx, &ecx.full, &edx.full);
 	hw_res->num_closid = edx.split.cos_max + 1;
 	r->cache.cbm_len = eax.split.cbm_len + 1;
-	r->default_ctrl = BIT_MASK(eax.split.cbm_len + 1) - 1;
-	r->cache.shareable_bits = ebx & r->default_ctrl;
+	default_ctrl = BIT_MASK(eax.split.cbm_len + 1) - 1;
+	r->cache.shareable_bits = ebx & default_ctrl;
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
 		r->cache.arch_has_sparse_bitmasks = ecx.split.noncont;
 	r->alloc_capable = true;
@@ -329,7 +326,7 @@ static u32 delay_bw_map(unsigned long bw, struct rdt_resource *r)
 		return MAX_MBA_BW - bw;
 
 	pr_warn_once("Non Linear delay-bw map not supported but queried\n");
-	return r->default_ctrl;
+	return MAX_MBA_BW;
 }
 
 static void mba_wrmsr_intel(struct msr_param *m)
@@ -438,7 +435,7 @@ static void setup_default_ctrlval(struct rdt_resource *r, u32 *dc)
 	 * For Memory Allocation: Set b/w requested to 100%
 	 */
 	for (i = 0; i < hw_res->num_closid; i++, dc++)
-		*dc = r->default_ctrl;
+		*dc = resctrl_get_default_ctrl(r);
 }
 
 static void ctrl_domain_free(struct rdt_hw_ctrl_domain *hw_dom)
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 23a01eaebd58..5d87f279085f 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -113,8 +113,9 @@ static int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
  */
 static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
 {
-	unsigned long first_bit, zero_bit, val;
+	u32 supported_bits = BIT_MASK(r->cache.cbm_len) - 1;
 	unsigned int cbm_len = r->cache.cbm_len;
+	unsigned long first_bit, zero_bit, val;
 	int ret;
 
 	ret = kstrtoul(buf, 16, &val);
@@ -123,7 +124,7 @@ static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
 		return false;
 	}
 
-	if ((r->cache.min_cbm_bits > 0 && val == 0) || val > r->default_ctrl) {
+	if ((r->cache.min_cbm_bits > 0 && val == 0) || val > supported_bits) {
 		rdt_last_cmd_puts("Mask out of range\n");
 		return false;
 	}
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 1e0bae1a9d95..cd8f65c12124 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -978,7 +978,7 @@ static int rdt_default_ctrl_show(struct kernfs_open_file *of,
 	struct resctrl_schema *s = of->kn->parent->priv;
 	struct rdt_resource *r = s->res;
 
-	seq_printf(seq, "%x\n", r->default_ctrl);
+	seq_printf(seq, "%x\n", resctrl_get_default_ctrl(r));
 	return 0;
 }
 
@@ -2882,7 +2882,7 @@ static int reset_all_ctrls(struct rdt_resource *r)
 		hw_dom = resctrl_to_arch_ctrl_dom(d);
 
 		for (i = 0; i < hw_res->num_closid; i++)
-			hw_dom->ctrl_val[i] = r->default_ctrl;
+			hw_dom->ctrl_val[i] = resctrl_get_default_ctrl(r);
 		msr_param.dom = d;
 		smp_call_function_any(&d->hdr.cpu_mask, rdt_ctrl_update, &msr_param, 1);
 	}
@@ -3417,7 +3417,7 @@ static void rdtgroup_init_mba(struct rdt_resource *r, u32 closid)
 		}
 
 		cfg = &d->staged_config[CDP_NONE];
-		cfg->new_ctrl = r->default_ctrl;
+		cfg->new_ctrl = resctrl_get_default_ctrl(r);
 		cfg->have_new_ctrl = true;
 	}
 }
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 465f3cf8c4bc..d16dc960f1fc 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -216,7 +216,6 @@ enum resctrl_schema_fmt {
  * @ctrl_domains:	RCU list of all control domains for this resource
  * @mon_domains:	RCU list of all monitor domains for this resource
  * @name:		Name to use in "schemata" file.
- * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
  * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
  * @cdp_capable:	Is the CDP feature available on this resource
@@ -233,7 +232,6 @@ struct rdt_resource {
 	struct list_head	ctrl_domains;
 	struct list_head	mon_domains;
 	char			*name;
-	u32			default_ctrl;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
 	bool			cdp_capable;
@@ -268,6 +266,23 @@ struct resctrl_schema {
 	u32				num_closid;
 };
 
+/**
+ * resctrl_get_default_ctrl() - Return the default control value for this
+ *                              resource.
+ * @r:		The resource whose default control type is queried.
+ */
+static inline u32 resctrl_get_default_ctrl(struct rdt_resource *r)
+{
+	switch (r->schema_fmt) {
+	case RESCTRL_SCHEMA_BITMAP:
+		return BIT_MASK(r->cache.cbm_len) - 1;
+	case RESCTRL_SCHEMA_RANGE:
+		return r->membw.max_bw;
+	}
+
+	return WARN_ON_ONCE(1);
+}
+
 /* The number of closid supported by this resource regardless of CDP */
 u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
 u32 resctrl_arch_system_num_rmid_idx(void);
-- 
2.39.5

[PATCH v8:for-boris 09/30] x86/resctrl: Add helper for setting CPU default properties

[James Morse]

rdtgroup_rmdir_ctrl() and rdtgroup_rmdir_mon() set the per-CPU
pqr_state for CPUs that were part of the rmdir()'d group.

Another architecture might not have a 'pqr_state', its hardware may
need the values in a different format. MPAM's equivalent of RMID values
are not unique, and always need the CLOSID to be provided too.

There is only one caller that modifies a single value,
(rdtgroup_rmdir_mon()). MPAM always needs both CLOSID and RMID
for the hardware value as these are written to the same system
register.

As rdtgroup_rmdir_mon() has the CLOSID on hand, only provide a
helper to set both values. These values are read by
__resctrl_sched_in(), but may be written by a different CPU without
any locking, add READ/WRTE_ONCE() to avoid torn values.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v1:
 * In rdtgroup_rmdir_mon(), (re)set CPU default closid based on the
   parent control group, to avoid the appearance of referencing
   something that we're in the process of destroying (even if it
   doesn't make a difference because the victim mon group necessarily
   has the same closid as the parent control group).

   Update comment to match.

   No (intentional) functional change.
---
 arch/x86/include/asm/resctrl.h         | 14 +++++++++++---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 20 ++++++++++++++------
 2 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 8b1b6ce1e51b..6908cd0e6e40 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -4,8 +4,9 @@
 
 #ifdef CONFIG_X86_CPU_RESCTRL
 
-#include <linux/sched.h>
 #include <linux/jump_label.h>
+#include <linux/percpu.h>
+#include <linux/sched.h>
 
 /*
  * This value can never be a valid CLOSID, and is used when mapping a
@@ -96,8 +97,8 @@ static inline void resctrl_arch_disable_mon(void)
 static inline void __resctrl_sched_in(struct task_struct *tsk)
 {
 	struct resctrl_pqr_state *state = this_cpu_ptr(&pqr_state);
-	u32 closid = state->default_closid;
-	u32 rmid = state->default_rmid;
+	u32 closid = READ_ONCE(state->default_closid);
+	u32 rmid = READ_ONCE(state->default_rmid);
 	u32 tmp;
 
 	/*
@@ -132,6 +133,13 @@ static inline unsigned int resctrl_arch_round_mon_val(unsigned int val)
 	return val * scale;
 }
 
+static inline void resctrl_arch_set_cpu_default_closid_rmid(int cpu, u32 closid,
+							    u32 rmid)
+{
+	WRITE_ONCE(per_cpu(pqr_state.default_closid, cpu), closid);
+	WRITE_ONCE(per_cpu(pqr_state.default_rmid, cpu), rmid);
+}
+
 static inline void resctrl_arch_set_closid_rmid(struct task_struct *tsk,
 						u32 closid, u32 rmid)
 {
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index cd8f65c12124..f706e5a288b1 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -3731,14 +3731,21 @@ static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
 static int rdtgroup_rmdir_mon(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
 {
 	struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
+	u32 closid, rmid;
 	int cpu;
 
 	/* Give any tasks back to the parent group */
 	rdt_move_group_tasks(rdtgrp, prdtgrp, tmpmask);
 
-	/* Update per cpu rmid of the moved CPUs first */
+	/*
+	 * Update per cpu closid/rmid of the moved CPUs first.
+	 * Note: the closid will not change, but the arch code still needs it.
+	 */
+	closid = prdtgrp->closid;
+	rmid = prdtgrp->mon.rmid;
 	for_each_cpu(cpu, &rdtgrp->cpu_mask)
-		per_cpu(pqr_state.default_rmid, cpu) = prdtgrp->mon.rmid;
+		resctrl_arch_set_cpu_default_closid_rmid(cpu, closid, rmid);
+
 	/*
 	 * Update the MSR on moved CPUs and CPUs which have moved
 	 * task running on them.
@@ -3771,6 +3778,7 @@ static int rdtgroup_ctrl_remove(struct rdtgroup *rdtgrp)
 
 static int rdtgroup_rmdir_ctrl(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
 {
+	u32 closid, rmid;
 	int cpu;
 
 	/* Give any tasks back to the default group */
@@ -3781,10 +3789,10 @@ static int rdtgroup_rmdir_ctrl(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
 		   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
 
 	/* Update per cpu closid and rmid of the moved CPUs first */
-	for_each_cpu(cpu, &rdtgrp->cpu_mask) {
-		per_cpu(pqr_state.default_closid, cpu) = rdtgroup_default.closid;
-		per_cpu(pqr_state.default_rmid, cpu) = rdtgroup_default.mon.rmid;
-	}
+	closid = rdtgroup_default.closid;
+	rmid = rdtgroup_default.mon.rmid;
+	for_each_cpu(cpu, &rdtgrp->cpu_mask)
+		resctrl_arch_set_cpu_default_closid_rmid(cpu, closid, rmid);
 
 	/*
 	 * Update the MSR on moved CPUs and CPUs which have moved
-- 
2.39.5

[PATCH v8:for-boris 10/30] x86/resctrl: Remove rdtgroup from update_cpu_closid_rmid()

[James Morse]

update_cpu_closid_rmid() takes a struct rdtgroup as an argument, which
it uses to update the local CPUs default pqr values. This is a problem
once the resctrl parts move out to /fs/, as the arch code cannot
poke around inside struct rdtgroup.

Rename update_cpu_closid_rmid() as resctrl_arch_sync_cpus_defaults()
to be used as the target of an IPI, and pass the effective CLOSID
and RMID in a new struct.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v1:
 * To clarify the meanings of the new helper and struct:

   Rename resctrl_arch_sync_cpu_default() to
   resctrl_arch_sync_cpu_closid_rmid();

   Rename struct resctrl_cpu_sync to struct resctrl_cpu_defaults;

   Flesh out the comment block in <linux/resctrl.h>.

   No functional change.
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 17 +++++++++++++----
 include/linux/resctrl.h                | 22 ++++++++++++++++++++++
 2 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index f706e5a288b1..62d9a50c7bba 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -355,13 +355,13 @@ static int rdtgroup_cpus_show(struct kernfs_open_file *of,
  * from update_closid_rmid() is protected against __switch_to() because
  * preemption is disabled.
  */
-static void update_cpu_closid_rmid(void *info)
+void resctrl_arch_sync_cpu_closid_rmid(void *info)
 {
-	struct rdtgroup *r = info;
+	struct resctrl_cpu_defaults *r = info;
 
 	if (r) {
 		this_cpu_write(pqr_state.default_closid, r->closid);
-		this_cpu_write(pqr_state.default_rmid, r->mon.rmid);
+		this_cpu_write(pqr_state.default_rmid, r->rmid);
 	}
 
 	/*
@@ -376,11 +376,20 @@ static void update_cpu_closid_rmid(void *info)
  * Update the PGR_ASSOC MSR on all cpus in @cpu_mask,
  *
  * Per task closids/rmids must have been set up before calling this function.
+ * @r may be NULL.
  */
 static void
 update_closid_rmid(const struct cpumask *cpu_mask, struct rdtgroup *r)
 {
-	on_each_cpu_mask(cpu_mask, update_cpu_closid_rmid, r, 1);
+	struct resctrl_cpu_defaults defaults, *p = NULL;
+
+	if (r) {
+		defaults.closid = r->closid;
+		defaults.rmid = r->mon.rmid;
+		p = &defaults;
+	}
+
+	on_each_cpu_mask(cpu_mask, resctrl_arch_sync_cpu_closid_rmid, p, 1);
 }
 
 static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index d16dc960f1fc..31808b3ddecb 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -266,6 +266,28 @@ struct resctrl_schema {
 	u32				num_closid;
 };
 
+struct resctrl_cpu_defaults {
+	u32 closid;
+	u32 rmid;
+};
+
+/**
+ * resctrl_arch_sync_cpu_closid_rmid() - Refresh this CPU's CLOSID and RMID.
+ *					 Call via IPI.
+ * @info:	If non-NULL, a pointer to a struct resctrl_cpu_defaults
+ *		specifying the new CLOSID and RMID for tasks in the default
+ *		resctrl ctrl and mon group when running on this CPU.  If NULL,
+ *		this CPU is not re-assigned to a different default group.
+ *
+ * Propagates reassignment of CPUs and/or tasks to different resctrl groups
+ * when requested by the resctrl core code.
+ *
+ * This function records the per-cpu defaults specified by @info (if any),
+ * and then reconfigures the CPU's hardware CLOSID and RMID for subsequent
+ * execution based on @current, in the same way as during a task switch.
+ */
+void resctrl_arch_sync_cpu_closid_rmid(void *info);
+
 /**
  * resctrl_get_default_ctrl() - Return the default control value for this
  *                              resource.
-- 
2.39.5

[PATCH v8:for-boris 11/30] x86/resctrl: Expose resctrl fs's init function to the rest of the kernel

[James Morse]

rdtgroup_init() needs exposing to the rest of the kernel so that arch
code can call it once it lives in core code. As this is one of the few
functions exposed, rename it to have "resctrl" in the name. The same
goes for the exit call.

Rename x86's arch code init functions for RDT to have an arch
prefix to make it clear these are part of the architecture code.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Tweaked the word 'export'

Changes since v4:
 * Changed the voice of some of the commit message.

Changes since v1:
 * Rename stale rdtgroup_init() to resctrl_init() in
   arch/x86/kernel/cpu/resctrl/monitor.c comments.

   No functional change.

 * [Commit message only] Minor rewording to avoid "impersonating code".

 * [Commit message only] Typo fix:
   s/to have the resctrl/to have resctrl/ in commit message.
---
 arch/x86/kernel/cpu/resctrl/core.c     | 12 ++++++------
 arch/x86/kernel/cpu/resctrl/internal.h |  3 ---
 arch/x86/kernel/cpu/resctrl/monitor.c  |  2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  8 ++++----
 include/linux/resctrl.h                |  3 +++
 5 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index d001ca43b53d..212995149eac 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -1061,7 +1061,7 @@ void resctrl_cpu_detect(struct cpuinfo_x86 *c)
 	}
 }
 
-static int __init resctrl_late_init(void)
+static int __init resctrl_arch_late_init(void)
 {
 	struct rdt_resource *r;
 	int state, ret;
@@ -1084,7 +1084,7 @@ static int __init resctrl_late_init(void)
 	if (state < 0)
 		return state;
 
-	ret = rdtgroup_init();
+	ret = resctrl_init();
 	if (ret) {
 		cpuhp_remove_state(state);
 		return ret;
@@ -1100,18 +1100,18 @@ static int __init resctrl_late_init(void)
 	return 0;
 }
 
-late_initcall(resctrl_late_init);
+late_initcall(resctrl_arch_late_init);
 
-static void __exit resctrl_exit(void)
+static void __exit resctrl_arch_exit(void)
 {
 	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
 
 	cpuhp_remove_state(rdt_online);
 
-	rdtgroup_exit();
+	resctrl_exit();
 
 	if (r->mon_capable)
 		rdt_put_mon_l3_config();
 }
 
-__exitcall(resctrl_exit);
+__exitcall(resctrl_arch_exit);
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index f975cd6cfe61..8291f1b59981 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -328,9 +328,6 @@ extern struct list_head rdt_all_groups;
 
 extern int max_name_width;
 
-int __init rdtgroup_init(void);
-void __exit rdtgroup_exit(void);
-
 /**
  * struct rftype - describe each file in the resctrl file system
  * @name:	File name
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 58b5b21349a8..e8388d19a579 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1027,7 +1027,7 @@ static int dom_data_init(struct rdt_resource *r)
 	/*
 	 * RESCTRL_RESERVED_CLOSID and RESCTRL_RESERVED_RMID are special and
 	 * are always allocated. These are used for the rdtgroup_default
-	 * control group, which will be setup later in rdtgroup_init().
+	 * control group, which will be setup later in resctrl_init().
 	 */
 	idx = resctrl_arch_rmid_idx_encode(RESCTRL_RESERVED_CLOSID,
 					   RESCTRL_RESERVED_RMID);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 62d9a50c7bba..b2dad689e780 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4235,14 +4235,14 @@ void resctrl_offline_cpu(unsigned int cpu)
 }
 
 /*
- * rdtgroup_init - rdtgroup initialization
+ * resctrl_init - resctrl filesystem initialization
  *
  * Setup resctrl file system including set up root, create mount point,
- * register rdtgroup filesystem, and initialize files under root directory.
+ * register resctrl filesystem, and initialize files under root directory.
  *
  * Return: 0 on success or -errno
  */
-int __init rdtgroup_init(void)
+int __init resctrl_init(void)
 {
 	int ret = 0;
 
@@ -4290,7 +4290,7 @@ int __init rdtgroup_init(void)
 	return ret;
 }
 
-void __exit rdtgroup_exit(void)
+void __exit resctrl_exit(void)
 {
 	debugfs_remove_recursive(debugfs_resctrl);
 	unregister_filesystem(&rdt_fs_type);
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 31808b3ddecb..f1979e375da9 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -402,4 +402,7 @@ void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_mon_domain *
 extern unsigned int resctrl_rmid_realloc_threshold;
 extern unsigned int resctrl_rmid_realloc_limit;
 
+int __init resctrl_init(void);
+void __exit resctrl_exit(void);
+
 #endif /* _RESCTRL_H */
-- 
2.39.5

[PATCH v8:for-boris 12/30] x86/resctrl: Move rdt_find_domain() to be visible to arch and fs code

[James Morse]

rdt_find_domain() finds a domain given a resource and a cache-id.
This is used by both the architecture code and the filesystem code.

After the filesystem code moves to live in /fs/, this helper is either
duplicated by all architectures, or needs exposing by the filesystem code.

Add the declaration to the global header file. As its now globally visible,
and has only a handful of callers, swap the 'rdt' for 'resctrl'. Move
the function to live with its caller in ctrlmondata.c as the filesystem
code will not have anything corresponding to core.c.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
---
Changes since v7:
 * "definition" -> "declaration"

Changes since v6:
 * Don't inline this helper.
 * Moved some words from the discussion into the commit message.

Changes since v5:
 * This patch replaced one that split off the 'new entry to insert'
   behaviour.
---
 arch/x86/kernel/cpu/resctrl/core.c        | 38 +++--------------------
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 24 +++++++++++++-
 arch/x86/kernel/cpu/resctrl/internal.h    |  2 --
 include/linux/resctrl.h                   | 14 +++++++++
 4 files changed, 41 insertions(+), 37 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 212995149eac..850cb8643c4a 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -394,36 +394,6 @@ void rdt_ctrl_update(void *arg)
 	hw_res->msr_update(m);
 }
 
-/*
- * rdt_find_domain - Search for a domain id in a resource domain list.
- *
- * Search the domain list to find the domain id. If the domain id is
- * found, return the domain. NULL otherwise.  If the domain id is not
- * found (and NULL returned) then the first domain with id bigger than
- * the input id can be returned to the caller via @pos.
- */
-struct rdt_domain_hdr *rdt_find_domain(struct list_head *h, int id,
-				       struct list_head **pos)
-{
-	struct rdt_domain_hdr *d;
-	struct list_head *l;
-
-	list_for_each(l, h) {
-		d = list_entry(l, struct rdt_domain_hdr, list);
-		/* When id is found, return its domain. */
-		if (id == d->id)
-			return d;
-		/* Stop searching when finding id's position in sorted list. */
-		if (id < d->id)
-			break;
-	}
-
-	if (pos)
-		*pos = l;
-
-	return NULL;
-}
-
 static void setup_default_ctrlval(struct rdt_resource *r, u32 *dc)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
@@ -534,7 +504,7 @@ static void domain_add_cpu_ctrl(int cpu, struct rdt_resource *r)
 		return;
 	}
 
-	hdr = rdt_find_domain(&r->ctrl_domains, id, &add_pos);
+	hdr = resctrl_find_domain(&r->ctrl_domains, id, &add_pos);
 	if (hdr) {
 		if (WARN_ON_ONCE(hdr->type != RESCTRL_CTRL_DOMAIN))
 			return;
@@ -589,7 +559,7 @@ static void domain_add_cpu_mon(int cpu, struct rdt_resource *r)
 		return;
 	}
 
-	hdr = rdt_find_domain(&r->mon_domains, id, &add_pos);
+	hdr = resctrl_find_domain(&r->mon_domains, id, &add_pos);
 	if (hdr) {
 		if (WARN_ON_ONCE(hdr->type != RESCTRL_MON_DOMAIN))
 			return;
@@ -654,7 +624,7 @@ static void domain_remove_cpu_ctrl(int cpu, struct rdt_resource *r)
 		return;
 	}
 
-	hdr = rdt_find_domain(&r->ctrl_domains, id, NULL);
+	hdr = resctrl_find_domain(&r->ctrl_domains, id, NULL);
 	if (!hdr) {
 		pr_warn("Can't find control domain for id=%d for CPU %d for resource %s\n",
 			id, cpu, r->name);
@@ -700,7 +670,7 @@ static void domain_remove_cpu_mon(int cpu, struct rdt_resource *r)
 		return;
 	}
 
-	hdr = rdt_find_domain(&r->mon_domains, id, NULL);
+	hdr = resctrl_find_domain(&r->mon_domains, id, NULL);
 	if (!hdr) {
 		pr_warn("Can't find monitor domain for id=%d for CPU %d for resource %s\n",
 			id, cpu, r->name);
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 5d87f279085f..763317ea2256 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -610,6 +610,28 @@ int rdtgroup_mba_mbps_event_show(struct kernfs_open_file *of,
 	return ret;
 }
 
+struct rdt_domain_hdr *resctrl_find_domain(struct list_head *h, int id,
+					   struct list_head **pos)
+{
+	struct rdt_domain_hdr *d;
+	struct list_head *l;
+
+	list_for_each(l, h) {
+		d = list_entry(l, struct rdt_domain_hdr, list);
+		/* When id is found, return its domain. */
+		if (id == d->id)
+			return d;
+		/* Stop searching when finding id's position in sorted list. */
+		if (id < d->id)
+			break;
+	}
+
+	if (pos)
+		*pos = l;
+
+	return NULL;
+}
+
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
 		    struct rdt_mon_domain *d, struct rdtgroup *rdtgrp,
 		    cpumask_t *cpumask, int evtid, int first)
@@ -695,7 +717,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 		 * This file provides data from a single domain. Search
 		 * the resource to find the domain with "domid".
 		 */
-		hdr = rdt_find_domain(&r->mon_domains, domid, NULL);
+		hdr = resctrl_find_domain(&r->mon_domains, domid, NULL);
 		if (!hdr || WARN_ON_ONCE(hdr->type != RESCTRL_MON_DOMAIN)) {
 			ret = -ENOENT;
 			goto out;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 8291f1b59981..da73404183da 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -581,8 +581,6 @@ void rdtgroup_kn_unlock(struct kernfs_node *kn);
 int rdtgroup_kn_mode_restrict(struct rdtgroup *r, const char *name);
 int rdtgroup_kn_mode_restore(struct rdtgroup *r, const char *name,
 			     umode_t mask);
-struct rdt_domain_hdr *rdt_find_domain(struct list_head *h, int id,
-				       struct list_head **pos);
 ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
 				char *buf, size_t nbytes, loff_t off);
 int rdtgroup_schemata_show(struct kernfs_open_file *of,
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index f1979e375da9..93d9a435f035 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -372,6 +372,20 @@ static inline void resctrl_arch_rmid_read_context_check(void)
 		might_sleep();
 }
 
+/**
+ * resctrl_find_domain() - Search for a domain id in a resource domain list.
+ * @h:		The domain list to search.
+ * @id:		The domain id to search for.
+ * @pos:	A pointer to position in the list id should be inserted.
+ *
+ * Search the domain list to find the domain id. If the domain id is
+ * found, return the domain. NULL otherwise.  If the domain id is not
+ * found (and NULL returned) then the first domain with id bigger than
+ * the input id can be returned to the caller via @pos.
+ */
+struct rdt_domain_hdr *resctrl_find_domain(struct list_head *h, int id,
+					   struct list_head **pos);
+
 /**
  * resctrl_arch_reset_rmid() - Reset any private state associated with rmid
  *			       and eventid.
-- 
2.39.5

[PATCH v8:for-boris 13/30] x86/resctrl: Move resctrl types to a separate header

[James Morse]

When resctrl is fully factored into core and per-arch code, each arch
will need to use some resctrl common definitions in order to define its
own specializations and helpers.  Following conventional practice, it
would be desirable to put the dependent arch definitions in an
<asm/resctrl.h> header that is included by the common <linux/resctrl.h>
header.  However, this can make it awkward to avoid a circular
dependency between <linux/resctrl.h> and the arch header.

To avoid such dependencies, move the affected common types and
constants into a new header that does not need to depend on
<linux/resctrl.h> or on the arch headers.

The same logic applies to the monitor-configuration defines, move these
too.

Some kind of enumeration for events is needed between the filesystem
and architecture code. Take the x86 definition as its convenient for
x86.

The definition of enum resctrl_event_id is needed to allow the
architecture code to define resctrl_arch_mon_ctx_alloc() and
resctrl_arch_mon_ctx_free().

The definition of enum resctrl_res_level is needed to allow the
architecture code to define resctrl_arch_set_cdp_enabled() and
resctrl_arch_get_cdp_enabled().

The bits for mbm_local_bytes_config et al are ABI, and must be the same
on all architectures. These are documented in
Documentation/arch/x86/resctrl.rst

The maintainers entry for these headers was missed when resctrl.h was
created. Add a wildcard entry to match both resctrl.h and
resctrl_types.h.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v6:
 * Used a different year in the boiler-plate copyright notice.

Change since v3:
 * Added header include.
 * Corrected lists in the commit message.

Changes since v2:
 * Added to the commit message why each of these things is necessary.
 * Moved the enum resctrl_conf_type back to resctrl.h - this week arm's
   CDP emulation code gets away without this...

Changes since v1:
 * [Commit message only] Rewrite commit message to clarify the the
   rationale for refactoring the headers in this way.
---
 MAINTAINERS                            |  1 +
 arch/x86/include/asm/resctrl.h         |  1 +
 arch/x86/kernel/cpu/resctrl/internal.h | 24 ------------
 include/linux/resctrl.h                | 21 +---------
 include/linux/resctrl_types.h          | 54 ++++++++++++++++++++++++++
 5 files changed, 57 insertions(+), 44 deletions(-)
 create mode 100644 include/linux/resctrl_types.h

diff --git a/MAINTAINERS b/MAINTAINERS
index efee40ea589f..3487ac429a9a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19881,6 +19881,7 @@ S:	Supported
 F:	Documentation/arch/x86/resctrl*
 F:	arch/x86/include/asm/resctrl.h
 F:	arch/x86/kernel/cpu/resctrl/
+F:	include/linux/resctrl*.h
 F:	tools/testing/selftests/resctrl/
 
 READ-COPY UPDATE (RCU)
diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 6908cd0e6e40..52f2326e2b1e 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -6,6 +6,7 @@
 
 #include <linux/jump_label.h>
 #include <linux/percpu.h>
+#include <linux/resctrl_types.h>
 #include <linux/sched.h>
 
 /*
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index da73404183da..5f3713fb2eaf 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -32,30 +32,6 @@
  */
 #define MBM_CNTR_WIDTH_OFFSET_MAX (62 - MBM_CNTR_WIDTH_BASE)
 
-/* Reads to Local DRAM Memory */
-#define READS_TO_LOCAL_MEM		BIT(0)
-
-/* Reads to Remote DRAM Memory */
-#define READS_TO_REMOTE_MEM		BIT(1)
-
-/* Non-Temporal Writes to Local Memory */
-#define NON_TEMP_WRITE_TO_LOCAL_MEM	BIT(2)
-
-/* Non-Temporal Writes to Remote Memory */
-#define NON_TEMP_WRITE_TO_REMOTE_MEM	BIT(3)
-
-/* Reads to Local Memory the system identifies as "Slow Memory" */
-#define READS_TO_LOCAL_S_MEM		BIT(4)
-
-/* Reads to Remote Memory the system identifies as "Slow Memory" */
-#define READS_TO_REMOTE_S_MEM		BIT(5)
-
-/* Dirty Victims to All Types of Memory */
-#define DIRTY_VICTIMS_TO_ALL_MEM	BIT(6)
-
-/* Max event bits supported */
-#define MAX_EVT_CONFIG_BITS		GENMASK(6, 0)
-
 /**
  * cpumask_any_housekeeping() - Choose any CPU in @mask, preferring those that
  *			        aren't marked nohz_full
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 93d9a435f035..326f7ba220e7 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -6,6 +6,7 @@
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/pid.h>
+#include <linux/resctrl_types.h>
 
 /* CLOSID, RMID value used by the default control group */
 #define RESCTRL_RESERVED_CLOSID		0
@@ -37,28 +38,8 @@ enum resctrl_conf_type {
 	CDP_DATA,
 };
 
-enum resctrl_res_level {
-	RDT_RESOURCE_L3,
-	RDT_RESOURCE_L2,
-	RDT_RESOURCE_MBA,
-	RDT_RESOURCE_SMBA,
-
-	/* Must be the last */
-	RDT_NUM_RESOURCES,
-};
-
 #define CDP_NUM_TYPES	(CDP_DATA + 1)
 
-/*
- * Event IDs, the values match those used to program IA32_QM_EVTSEL before
- * reading IA32_QM_CTR on RDT systems.
- */
-enum resctrl_event_id {
-	QOS_L3_OCCUP_EVENT_ID		= 0x01,
-	QOS_L3_MBM_TOTAL_EVENT_ID	= 0x02,
-	QOS_L3_MBM_LOCAL_EVENT_ID	= 0x03,
-};
-
 /**
  * struct resctrl_staged_config - parsed configuration to be applied
  * @new_ctrl:		new ctrl value to be loaded
diff --git a/include/linux/resctrl_types.h b/include/linux/resctrl_types.h
new file mode 100644
index 000000000000..f26450b3326b
--- /dev/null
+++ b/include/linux/resctrl_types.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2025 Arm Ltd.
+ * Based on arch/x86/kernel/cpu/resctrl/internal.h
+ */
+
+#ifndef __LINUX_RESCTRL_TYPES_H
+#define __LINUX_RESCTRL_TYPES_H
+
+/* Reads to Local DRAM Memory */
+#define READS_TO_LOCAL_MEM		BIT(0)
+
+/* Reads to Remote DRAM Memory */
+#define READS_TO_REMOTE_MEM		BIT(1)
+
+/* Non-Temporal Writes to Local Memory */
+#define NON_TEMP_WRITE_TO_LOCAL_MEM	BIT(2)
+
+/* Non-Temporal Writes to Remote Memory */
+#define NON_TEMP_WRITE_TO_REMOTE_MEM	BIT(3)
+
+/* Reads to Local Memory the system identifies as "Slow Memory" */
+#define READS_TO_LOCAL_S_MEM		BIT(4)
+
+/* Reads to Remote Memory the system identifies as "Slow Memory" */
+#define READS_TO_REMOTE_S_MEM		BIT(5)
+
+/* Dirty Victims to All Types of Memory */
+#define DIRTY_VICTIMS_TO_ALL_MEM	BIT(6)
+
+/* Max event bits supported */
+#define MAX_EVT_CONFIG_BITS		GENMASK(6, 0)
+
+enum resctrl_res_level {
+	RDT_RESOURCE_L3,
+	RDT_RESOURCE_L2,
+	RDT_RESOURCE_MBA,
+	RDT_RESOURCE_SMBA,
+
+	/* Must be the last */
+	RDT_NUM_RESOURCES,
+};
+
+/*
+ * Event IDs, the values match those used to program IA32_QM_EVTSEL before
+ * reading IA32_QM_CTR on RDT systems.
+ */
+enum resctrl_event_id {
+	QOS_L3_OCCUP_EVENT_ID		= 0x01,
+	QOS_L3_MBM_TOTAL_EVENT_ID	= 0x02,
+	QOS_L3_MBM_LOCAL_EVENT_ID	= 0x03,
+};
+
+#endif /* __LINUX_RESCTRL_TYPES_H */
-- 
2.39.5

[PATCH v8:for-boris 14/30] x86/resctrl: Add an arch helper to reset one resource

[James Morse]

On umount(), resctrl resets each resource back to its default
configuration. It only ever does this for all resources in one go.

reset_all_ctrls() is architecture specific as it works with struct
rdt_hw_resource.

Make reset_all_ctrls() an arch helper that resets one resource.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Move the arch/fs split into the for-each loop at Reinette's suggestion.
 * Dropped a bunch of tags and rewrote the commit message.

Changes since v1:
 * Rename the for_each_capable_rdt_resource() introduced in the new
   function resctrl_arch_reset_resources(), back to
   for_each_alloc_capable_rdt_resource() as it was in the original code.

   The change looked unintentional; and presumably a resource that does
   not support resource allocation doesn't have any properties to
   reset...
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 9 +++++----
 include/linux/resctrl.h                | 9 +++++++++
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index b2dad689e780..9eb57ebb36c6 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2867,7 +2867,7 @@ static int rdt_init_fs_context(struct fs_context *fc)
 	return 0;
 }
 
-static int reset_all_ctrls(struct rdt_resource *r)
+void resctrl_arch_reset_all_ctrls(struct rdt_resource *r)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
 	struct rdt_hw_ctrl_domain *hw_dom;
@@ -2896,7 +2896,7 @@ static int reset_all_ctrls(struct rdt_resource *r)
 		smp_call_function_any(&d->hdr.cpu_mask, rdt_ctrl_update, &msr_param, 1);
 	}
 
-	return 0;
+	return;
 }
 
 /*
@@ -3015,9 +3015,10 @@ static void rdt_kill_sb(struct super_block *sb)
 
 	rdt_disable_ctx();
 
-	/*Put everything back to default values. */
+	/* Put everything back to default values. */
 	for_each_alloc_capable_rdt_resource(r)
-		reset_all_ctrls(r);
+		resctrl_arch_reset_all_ctrls(r);
+
 	rmdir_all_sub();
 	rdt_pseudo_lock_release();
 	rdtgroup_default.mode = RDT_MODE_SHAREABLE;
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 326f7ba220e7..487b9657a7b5 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -394,6 +394,15 @@ void resctrl_arch_reset_rmid(struct rdt_resource *r, struct rdt_mon_domain *d,
  */
 void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_mon_domain *d);
 
+/**
+ * resctrl_arch_reset_all_ctrls() - Reset the control for each CLOSID to its
+ *				    default.
+ * @r:		The resctrl resource to reset.
+ *
+ * This can be called from any CPU.
+ */
+void resctrl_arch_reset_all_ctrls(struct rdt_resource *r);
+
 extern unsigned int resctrl_rmid_realloc_threshold;
 extern unsigned int resctrl_rmid_realloc_limit;
 
-- 
2.39.5

[PATCH v8:for-boris 15/30] x86/resctrl: Move monitor exit work to a resctrl exit call

[James Morse]

rdt_put_mon_l3_config() is called via the architecture's
resctrl_arch_exit() call, and appears to free the rmid_ptrs[]
and closid_num_dirty_rmid[] arrays. In reality this code is marked
__exit, and is removed by the linker as resctrl can't be built
as a module.

To separate the filesystem and architecture parts of resctrl,
this free()ing work needs to be triggered by the filesystem,
as these structures belong to the filesystem code.

Rename rdt_put_mon_l3_config() resctrl_mon_resource_exit()
and call it from resctrl_exit(). The kfree() is currently
dependent on r->mon_capable.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v4:
 * Added __exit so it can be removed in the next patch.

Changes since v3:
 * Moved r->mon_capable check under the lock.
 * Dropped references to resctrl_mon_resource_init() from the commit message.
 * Fixed more resctrl typos,

Changes since v2:
 * Dropped __exit as needed in the next patch.

Change since v1:
 * [Commit message only] Typo fixes:
   s/restrl/resctrl/g
   s/resctl/resctrl/g

 * [Commit message only] Reword second paragraph to remove reference to
   the MPAM error interrupt, which provides background rationale for a
   later patch rather than for this patch, and so it is not really
   relevant here.
---
 arch/x86/kernel/cpu/resctrl/core.c     |  5 -----
 arch/x86/kernel/cpu/resctrl/internal.h |  2 +-
 arch/x86/kernel/cpu/resctrl/monitor.c  | 12 +++++++++---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  2 ++
 4 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 850cb8643c4a..a1577bdd3c90 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -1074,14 +1074,9 @@ late_initcall(resctrl_arch_late_init);
 
 static void __exit resctrl_arch_exit(void)
 {
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
-
 	cpuhp_remove_state(rdt_online);
 
 	resctrl_exit();
-
-	if (r->mon_capable)
-		rdt_put_mon_l3_config();
 }
 
 __exitcall(resctrl_arch_exit);
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 5f3713fb2eaf..73005ca2dda1 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -586,7 +586,7 @@ void closid_free(int closid);
 int alloc_rmid(u32 closid);
 void free_rmid(u32 closid, u32 rmid);
 int rdt_get_mon_l3_config(struct rdt_resource *r);
-void __exit rdt_put_mon_l3_config(void);
+void __exit resctrl_mon_resource_exit(void);
 bool __init rdt_cpu_has(int flag);
 void mon_event_count(void *info);
 int rdtgroup_mondata_show(struct seq_file *m, void *arg);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index e8388d19a579..15e8c0190bfc 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1040,10 +1040,13 @@ static int dom_data_init(struct rdt_resource *r)
 	return err;
 }
 
-static void __exit dom_data_exit(void)
+static void __exit dom_data_exit(struct rdt_resource *r)
 {
 	mutex_lock(&rdtgroup_mutex);
 
+	if (!r->mon_capable)
+		goto out_unlock;
+
 	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) {
 		kfree(closid_num_dirty_rmid);
 		closid_num_dirty_rmid = NULL;
@@ -1052,6 +1055,7 @@ static void __exit dom_data_exit(void)
 	kfree(rmid_ptrs);
 	rmid_ptrs = NULL;
 
+out_unlock:
 	mutex_unlock(&rdtgroup_mutex);
 }
 
@@ -1237,9 +1241,11 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 	return 0;
 }
 
-void __exit rdt_put_mon_l3_config(void)
+void __exit resctrl_mon_resource_exit(void)
 {
-	dom_data_exit();
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
+
+	dom_data_exit(r);
 }
 
 void __init intel_rdt_mbm_apply_quirk(void)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 9eb57ebb36c6..42c48e79364d 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4296,4 +4296,6 @@ void __exit resctrl_exit(void)
 	debugfs_remove_recursive(debugfs_resctrl);
 	unregister_filesystem(&rdt_fs_type);
 	sysfs_remove_mount_point(fs_kobj, "resctrl");
+
+	resctrl_mon_resource_exit();
 }
-- 
2.39.5

[PATCH v8:for-boris 16/30] x86/resctrl: Move monitor init work to a resctrl init call

[James Morse]

rdt_get_mon_l3_config() is called from the architecture's
resctrl_arch_late_init(), and initialises both architecture specific
fields, such as hw_res->mon_scale and resctrl filesystem fields
by calling dom_data_init().

To separate the filesystem and architecture parts of resctrl, this
function needs splitting up.

Add resctrl_mon_resource_init() to do the filesystem specific work,
and call it from resctrl_init(). This runs later, but is still before
the filesystem is mounted and the rmid_ptrs[] array can be used.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>

---
Changes since v4:
 * Removed __exit markers

Changes since v3:
 * Added a comment over resctrl_mon_resource_init().
 * Added a comment over domain_setup_mon_state() to warn of cpuhp ordering.
 * Added __init to resctrl_mon_resource_init().

Changes since v2:
 * Added error handling for the case sysfs files can't be created.
---
 arch/x86/kernel/cpu/resctrl/internal.h |  3 +-
 arch/x86/kernel/cpu/resctrl/monitor.c  | 40 ++++++++++++++++++++------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 22 +++++++++++++-
 3 files changed, 54 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 73005ca2dda1..70fbb902e85e 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -586,13 +586,14 @@ void closid_free(int closid);
 int alloc_rmid(u32 closid);
 void free_rmid(u32 closid, u32 rmid);
 int rdt_get_mon_l3_config(struct rdt_resource *r);
-void __exit resctrl_mon_resource_exit(void);
+void resctrl_mon_resource_exit(void);
 bool __init rdt_cpu_has(int flag);
 void mon_event_count(void *info);
 int rdtgroup_mondata_show(struct seq_file *m, void *arg);
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
 		    struct rdt_mon_domain *d, struct rdtgroup *rdtgrp,
 		    cpumask_t *cpumask, int evtid, int first);
+int __init resctrl_mon_resource_init(void);
 void mbm_setup_overflow_handler(struct rdt_mon_domain *dom,
 				unsigned long delay_ms,
 				int exclude_cpu);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 15e8c0190bfc..1730ba814834 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1040,7 +1040,7 @@ static int dom_data_init(struct rdt_resource *r)
 	return err;
 }
 
-static void __exit dom_data_exit(struct rdt_resource *r)
+static void dom_data_exit(struct rdt_resource *r)
 {
 	mutex_lock(&rdtgroup_mutex);
 
@@ -1176,12 +1176,40 @@ static __init int snc_get_config(void)
 	return ret;
 }
 
+/**
+ * resctrl_mon_resource_init() - Initialise global monitoring structures.
+ *
+ * Allocate and initialise global monitor resources that do not belong to a
+ * specific domain. i.e. the rmid_ptrs[] used for the limbo and free lists.
+ * Called once during boot after the struct rdt_resource's have been configured
+ * but before the filesystem is mounted.
+ * Resctrl's cpuhp callbacks may be called before this point to bring a domain
+ * online.
+ *
+ * Returns 0 for success, or -ENOMEM.
+ */
+int __init resctrl_mon_resource_init(void)
+{
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
+	int ret;
+
+	if (!r->mon_capable)
+		return 0;
+
+	ret = dom_data_init(r);
+	if (ret)
+		return ret;
+
+	l3_mon_evt_init(r);
+
+	return 0;
+}
+
 int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 {
 	unsigned int mbm_offset = boot_cpu_data.x86_cache_mbm_width_offset;
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
 	unsigned int threshold;
-	int ret;
 
 	snc_nodes_per_l3_cache = snc_get_config();
 
@@ -1211,10 +1239,6 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 	 */
 	resctrl_rmid_realloc_threshold = resctrl_arch_round_mon_val(threshold);
 
-	ret = dom_data_init(r);
-	if (ret)
-		return ret;
-
 	if (rdt_cpu_has(X86_FEATURE_BMEC)) {
 		u32 eax, ebx, ecx, edx;
 
@@ -1234,14 +1258,12 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 		}
 	}
 
-	l3_mon_evt_init(r);
-
 	r->mon_capable = true;
 
 	return 0;
 }
 
-void __exit resctrl_mon_resource_exit(void)
+void resctrl_mon_resource_exit(void)
 {
 	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 42c48e79364d..badac3f5da72 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4102,6 +4102,19 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d
 	mutex_unlock(&rdtgroup_mutex);
 }
 
+/**
+ * domain_setup_mon_state() -  Initialise domain monitoring structures.
+ * @r:	The resource for the newly online domain.
+ * @d:	The newly online domain.
+ *
+ * Allocate monitor resources that belong to this domain.
+ * Called when the first CPU of a domain comes online, regardless of whether
+ * the filesystem is mounted.
+ * During boot this may be called before global allocations have been made by
+ * resctrl_mon_resource_init().
+ *
+ * Returns 0 for success, or -ENOMEM.
+ */
 static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_mon_domain *d)
 {
 	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
@@ -4252,9 +4265,15 @@ int __init resctrl_init(void)
 
 	rdtgroup_setup_default();
 
+	ret = resctrl_mon_resource_init();
+	if (ret)
+		return ret;
+
 	ret = sysfs_create_mount_point(fs_kobj, "resctrl");
-	if (ret)
+	if (ret) {
+		resctrl_mon_resource_exit();
 		return ret;
+	}
 
 	ret = register_filesystem(&rdt_fs_type);
 	if (ret)
@@ -4287,6 +4306,7 @@ int __init resctrl_init(void)
 
 cleanup_mountpoint:
 	sysfs_remove_mount_point(fs_kobj, "resctrl");
+	resctrl_mon_resource_exit();
 
 	return ret;
 }
-- 
2.39.5

[PATCH v8:for-boris 17/30] x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkers

[James Morse]

The for_each_*_rdt_resource() helpers walk the architecture's array
of structures, using the resctrl visible part as an iterator. These
became over-complex when the structures were split into a
filesystem and architecture-specific struct. This approach avoided
the need to touch every call site, and was done before there was a
helper to retrieve a resource by rid.

Once the filesystem parts of resctrl are moved to /fs/, both the
architecture's resource array, and the definition of those structures
is no longer accessible. To support resctrl, each architecture would
have to provide equally complex macros.

Rewrite the macro to make use of resctrl_arch_get_resource(), and
move these to include/linux/resctrl.h so existing x86 arch code continues
to use them.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Fixed an off by one in for_each_rdt_resource().
 * Added header file path to commit message.

Changes since v3:
 * Restructure the existing macros instead of open-coding the for loop.

Changes since v1:
 * [Whitespace only] Fix bogus whitespace introduced in
   rdtgroup_create_info_dir().

 * [Commit message only] Typo fix:
   s/architectures/architecture's/g
---
 arch/x86/kernel/cpu/resctrl/internal.h | 29 --------------------------
 include/linux/resctrl.h                | 18 ++++++++++++++++
 2 files changed, 18 insertions(+), 29 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 70fbb902e85e..82dbc1606663 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -475,14 +475,6 @@ extern struct rdtgroup rdtgroup_default;
 extern struct dentry *debugfs_resctrl;
 extern enum resctrl_event_id mba_mbps_default_event;
 
-static inline struct rdt_resource *resctrl_inc(struct rdt_resource *res)
-{
-	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(res);
-
-	hw_res++;
-	return &hw_res->r_resctrl;
-}
-
 static inline bool resctrl_arch_get_cdp_enabled(enum resctrl_res_level l)
 {
 	return rdt_resources_all[l].cdp_enabled;
@@ -492,27 +484,6 @@ int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable);
 
 void arch_mon_domain_online(struct rdt_resource *r, struct rdt_mon_domain *d);
 
-/*
- * To return the common struct rdt_resource, which is contained in struct
- * rdt_hw_resource, walk the resctrl member of struct rdt_hw_resource.
- */
-#define for_each_rdt_resource(r)					      \
-	for (r = &rdt_resources_all[0].r_resctrl;			      \
-	     r <= &rdt_resources_all[RDT_NUM_RESOURCES - 1].r_resctrl;	      \
-	     r = resctrl_inc(r))
-
-#define for_each_capable_rdt_resource(r)				      \
-	for_each_rdt_resource(r)					      \
-		if (r->alloc_capable || r->mon_capable)
-
-#define for_each_alloc_capable_rdt_resource(r)				      \
-	for_each_rdt_resource(r)					      \
-		if (r->alloc_capable)
-
-#define for_each_mon_capable_rdt_resource(r)				      \
-	for_each_rdt_resource(r)					      \
-		if (r->mon_capable)
-
 /* CPUID.(EAX=10H, ECX=ResID=1).EAX */
 union cpuid_0x10_1_eax {
 	struct {
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 487b9657a7b5..a392480dc4b6 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -26,6 +26,24 @@ int proc_resctrl_show(struct seq_file *m,
 /* max value for struct rdt_domain's mbps_val */
 #define MBA_MAX_MBPS   U32_MAX
 
+/* Walk all possible resources, with variants for only controls or monitors. */
+#define for_each_rdt_resource(_r)						\
+	for ((_r) = resctrl_arch_get_resource(0);				\
+	     (_r) && (_r)->rid < RDT_NUM_RESOURCES;				\
+	     (_r) = resctrl_arch_get_resource((_r)->rid + 1))
+
+#define for_each_capable_rdt_resource(r)				      \
+	for_each_rdt_resource((r))					      \
+		if ((r)->alloc_capable || (r)->mon_capable)
+
+#define for_each_alloc_capable_rdt_resource(r)				      \
+	for_each_rdt_resource((r))					      \
+		if ((r)->alloc_capable)
+
+#define for_each_mon_capable_rdt_resource(r)				      \
+	for_each_rdt_resource((r))					      \
+		if ((r)->mon_capable)
+
 /**
  * enum resctrl_conf_type - The type of configuration.
  * @CDP_NONE:	No prioritisation, both code and data are controlled or monitored.
-- 
2.39.5

[PATCH v8:for-boris 18/30] x86/resctrl: Move the is_mbm_*_enabled() helpers to asm/resctrl.h

[James Morse]

The architecture specific parts of resctrl provide helpers like
is_mbm_total_enabled() and is_mbm_local_enabled() to hide accesses
to the rdt_mon_features bitmap.

Exposing a group of helpers between the architecture and filesystem code
is preferable to a single unsigned-long like rdt_mon_features. Helpers
can be more readable and have a well defined behaviour, while allowing
architectures to hide more complex behaviour.

Once the filesystem parts of resctrl are moved, these existing helpers can
no longer live in internal.h. Move them to include/linux/resctrl.h
Once these are exposed to the wider kernel, they should have a
'resctrl_arch_' prefix, to fit the rest of the arch<->fs interface.

Move and rename the helpers that touch rdt_mon_features directly.
is_mbm_event() and is_mbm_enabled() are only called from rdtgroup.c,
so can be moved into that file.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
---
Chagnes since v6:
 * Dropped a spurious check re-introduced by a bad rebase conflict.

Changes since v5:
 * Removed the word 'export' due to its kernel-specific meaning.
 * Reworded commit message.
---
 arch/x86/include/asm/resctrl.h            | 16 +++++++++
 arch/x86/kernel/cpu/resctrl/core.c        |  8 ++---
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  4 +--
 arch/x86/kernel/cpu/resctrl/internal.h    | 27 ---------------
 arch/x86/kernel/cpu/resctrl/monitor.c     | 16 ++++-----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 40 +++++++++++++++--------
 6 files changed, 56 insertions(+), 55 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 52f2326e2b1e..6d4c7ea2c9e3 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -42,6 +42,7 @@ DECLARE_PER_CPU(struct resctrl_pqr_state, pqr_state);
 
 extern bool rdt_alloc_capable;
 extern bool rdt_mon_capable;
+extern unsigned int rdt_mon_features;
 
 DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
 DECLARE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
@@ -81,6 +82,21 @@ static inline void resctrl_arch_disable_mon(void)
 	static_branch_dec_cpuslocked(&rdt_enable_key);
 }
 
+static inline bool resctrl_arch_is_llc_occupancy_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID));
+}
+
+static inline bool resctrl_arch_is_mbm_total_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID));
+}
+
+static inline bool resctrl_arch_is_mbm_local_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID));
+}
+
 /*
  * __resctrl_sched_in() - Writes the task's CLOSid/RMID to IA32_PQR_MSR
  *
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index a1577bdd3c90..eba210db4a7b 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -453,13 +453,13 @@ static int arch_domain_mbm_alloc(u32 num_rmid, struct rdt_hw_mon_domain *hw_dom)
 {
 	size_t tsize;
 
-	if (is_mbm_total_enabled()) {
+	if (resctrl_arch_is_mbm_total_enabled()) {
 		tsize = sizeof(*hw_dom->arch_mbm_total);
 		hw_dom->arch_mbm_total = kcalloc(num_rmid, tsize, GFP_KERNEL);
 		if (!hw_dom->arch_mbm_total)
 			return -ENOMEM;
 	}
-	if (is_mbm_local_enabled()) {
+	if (resctrl_arch_is_mbm_local_enabled()) {
 		tsize = sizeof(*hw_dom->arch_mbm_local);
 		hw_dom->arch_mbm_local = kcalloc(num_rmid, tsize, GFP_KERNEL);
 		if (!hw_dom->arch_mbm_local) {
@@ -908,9 +908,9 @@ static __init bool get_rdt_mon_resources(void)
 	if (!rdt_mon_features)
 		return false;
 
-	if (is_mbm_local_enabled())
+	if (resctrl_arch_is_mbm_local_enabled())
 		mba_mbps_default_event = QOS_L3_MBM_LOCAL_EVENT_ID;
-	else if (is_mbm_total_enabled())
+	else if (resctrl_arch_is_mbm_total_enabled())
 		mba_mbps_default_event = QOS_L3_MBM_TOTAL_EVENT_ID;
 
 	return !rdt_get_mon_l3_config(r);
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 763317ea2256..1ecc93282b7d 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -559,12 +559,12 @@ ssize_t rdtgroup_mba_mbps_event_write(struct kernfs_open_file *of,
 	rdt_last_cmd_clear();
 
 	if (!strcmp(buf, "mbm_local_bytes")) {
-		if (is_mbm_local_enabled())
+		if (resctrl_arch_is_mbm_local_enabled())
 			rdtgrp->mba_mbps_event = QOS_L3_MBM_LOCAL_EVENT_ID;
 		else
 			ret = -EINVAL;
 	} else if (!strcmp(buf, "mbm_total_bytes")) {
-		if (is_mbm_total_enabled())
+		if (resctrl_arch_is_mbm_total_enabled())
 			rdtgrp->mba_mbps_event = QOS_L3_MBM_TOTAL_EVENT_ID;
 		else
 			ret = -EINVAL;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 82dbc1606663..4a5996d1e060 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -156,7 +156,6 @@ struct rmid_read {
 	void			*arch_mon_ctx;
 };
 
-extern unsigned int rdt_mon_features;
 extern struct list_head resctrl_schema_all;
 extern bool resctrl_mounted;
 
@@ -406,32 +405,6 @@ struct msr_param {
 	u32			high;
 };
 
-static inline bool is_llc_occupancy_enabled(void)
-{
-	return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID));
-}
-
-static inline bool is_mbm_total_enabled(void)
-{
-	return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID));
-}
-
-static inline bool is_mbm_local_enabled(void)
-{
-	return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID));
-}
-
-static inline bool is_mbm_enabled(void)
-{
-	return (is_mbm_total_enabled() || is_mbm_local_enabled());
-}
-
-static inline bool is_mbm_event(int e)
-{
-	return (e >= QOS_L3_MBM_TOTAL_EVENT_ID &&
-		e <= QOS_L3_MBM_LOCAL_EVENT_ID);
-}
-
 /**
  * struct rdt_hw_resource - arch private attributes of a resctrl resource
  * @r_resctrl:		Attributes of the resource used directly by resctrl.
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 1730ba814834..d883ed56ec90 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -295,11 +295,11 @@ void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_mon_domain *
 {
 	struct rdt_hw_mon_domain *hw_dom = resctrl_to_arch_mon_dom(d);
 
-	if (is_mbm_total_enabled())
+	if (resctrl_arch_is_mbm_total_enabled())
 		memset(hw_dom->arch_mbm_total, 0,
 		       sizeof(*hw_dom->arch_mbm_total) * r->num_rmid);
 
-	if (is_mbm_local_enabled())
+	if (resctrl_arch_is_mbm_local_enabled())
 		memset(hw_dom->arch_mbm_local, 0,
 		       sizeof(*hw_dom->arch_mbm_local) * r->num_rmid);
 }
@@ -569,7 +569,7 @@ void free_rmid(u32 closid, u32 rmid)
 
 	entry = __rmid_entry(idx);
 
-	if (is_llc_occupancy_enabled())
+	if (resctrl_arch_is_llc_occupancy_enabled())
 		add_rmid_to_limbo(entry);
 	else
 		list_add_tail(&entry->list, &rmid_free_lru);
@@ -852,10 +852,10 @@ static void mbm_update(struct rdt_resource *r, struct rdt_mon_domain *d,
 	 * This is protected from concurrent reads from user as both
 	 * the user and overflow handler hold the global mutex.
 	 */
-	if (is_mbm_total_enabled())
+	if (resctrl_arch_is_mbm_total_enabled())
 		mbm_update_one_event(r, d, closid, rmid, QOS_L3_MBM_TOTAL_EVENT_ID);
 
-	if (is_mbm_local_enabled())
+	if (resctrl_arch_is_mbm_local_enabled())
 		mbm_update_one_event(r, d, closid, rmid, QOS_L3_MBM_LOCAL_EVENT_ID);
 }
 
@@ -1085,11 +1085,11 @@ static void l3_mon_evt_init(struct rdt_resource *r)
 {
 	INIT_LIST_HEAD(&r->evt_list);
 
-	if (is_llc_occupancy_enabled())
+	if (resctrl_arch_is_llc_occupancy_enabled())
 		list_add_tail(&llc_occupancy_event.list, &r->evt_list);
-	if (is_mbm_total_enabled())
+	if (resctrl_arch_is_mbm_total_enabled())
 		list_add_tail(&mbm_total_event.list, &r->evt_list);
-	if (is_mbm_local_enabled())
+	if (resctrl_arch_is_mbm_local_enabled())
 		list_add_tail(&mbm_local_event.list, &r->evt_list);
 }
 
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index badac3f5da72..eb32fbc3abea 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -117,6 +117,18 @@ void rdt_staged_configs_clear(void)
 	}
 }
 
+static bool resctrl_is_mbm_enabled(void)
+{
+	return (resctrl_arch_is_mbm_total_enabled() ||
+		resctrl_arch_is_mbm_local_enabled());
+}
+
+static bool resctrl_is_mbm_event(int e)
+{
+	return (e >= QOS_L3_MBM_TOTAL_EVENT_ID &&
+		e <= QOS_L3_MBM_LOCAL_EVENT_ID);
+}
+
 /*
  * Trivial allocator for CLOSIDs. Since h/w only supports a small number,
  * we can keep a bitmap of free CLOSIDs in a single integer.
@@ -164,7 +176,7 @@ static int closid_alloc(void)
 	lockdep_assert_held(&rdtgroup_mutex);
 
 	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID) &&
-	    is_llc_occupancy_enabled()) {
+	    resctrl_arch_is_llc_occupancy_enabled()) {
 		cleanest_closid = resctrl_find_cleanest_closid();
 		if (cleanest_closid < 0)
 			return cleanest_closid;
@@ -2378,7 +2390,7 @@ static bool supports_mba_mbps(void)
 	struct rdt_resource *rmbm = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 
-	return (is_mbm_enabled() &&
+	return (resctrl_is_mbm_enabled() &&
 		r->alloc_capable && is_mba_linear() &&
 		r->ctrl_scope == rmbm->mon_scope);
 }
@@ -2756,7 +2768,7 @@ static int rdt_get_tree(struct fs_context *fc)
 	if (resctrl_arch_alloc_capable() || resctrl_arch_mon_capable())
 		resctrl_mounted = true;
 
-	if (is_mbm_enabled()) {
+	if (resctrl_is_mbm_enabled()) {
 		r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 		list_for_each_entry(dom, &r->mon_domains, hdr.list)
 			mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL,
@@ -3125,7 +3137,7 @@ static int mon_add_all_files(struct kernfs_node *kn, struct rdt_mon_domain *d,
 		if (ret)
 			return ret;
 
-		if (!do_sum && is_mbm_event(mevt->evtid))
+		if (!do_sum && resctrl_is_mbm_event(mevt->evtid))
 			mon_event_read(&rr, r, d, prgrp, &d->hdr.cpu_mask, mevt->evtid, true);
 	}
 
@@ -4082,9 +4094,9 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d
 	if (resctrl_mounted && resctrl_arch_mon_capable())
 		rmdir_mondata_subdir_allrdtgrp(r, d);
 
-	if (is_mbm_enabled())
+	if (resctrl_is_mbm_enabled())
 		cancel_delayed_work(&d->mbm_over);
-	if (is_llc_occupancy_enabled() && has_busy_rmid(d)) {
+	if (resctrl_arch_is_llc_occupancy_enabled() && has_busy_rmid(d)) {
 		/*
 		 * When a package is going down, forcefully
 		 * decrement rmid->ebusy. There is no way to know
@@ -4120,12 +4132,12 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_mon_domain
 	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
 	size_t tsize;
 
-	if (is_llc_occupancy_enabled()) {
+	if (resctrl_arch_is_llc_occupancy_enabled()) {
 		d->rmid_busy_llc = bitmap_zalloc(idx_limit, GFP_KERNEL);
 		if (!d->rmid_busy_llc)
 			return -ENOMEM;
 	}
-	if (is_mbm_total_enabled()) {
+	if (resctrl_arch_is_mbm_total_enabled()) {
 		tsize = sizeof(*d->mbm_total);
 		d->mbm_total = kcalloc(idx_limit, tsize, GFP_KERNEL);
 		if (!d->mbm_total) {
@@ -4133,7 +4145,7 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_mon_domain
 			return -ENOMEM;
 		}
 	}
-	if (is_mbm_local_enabled()) {
+	if (resctrl_arch_is_mbm_local_enabled()) {
 		tsize = sizeof(*d->mbm_local);
 		d->mbm_local = kcalloc(idx_limit, tsize, GFP_KERNEL);
 		if (!d->mbm_local) {
@@ -4172,13 +4184,13 @@ int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d)
 	if (err)
 		goto out_unlock;
 
-	if (is_mbm_enabled()) {
+	if (resctrl_is_mbm_enabled()) {
 		INIT_DELAYED_WORK(&d->mbm_over, mbm_handle_overflow);
 		mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL,
 					   RESCTRL_PICK_ANY_CPU);
 	}
 
-	if (is_llc_occupancy_enabled())
+	if (resctrl_arch_is_llc_occupancy_enabled())
 		INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo);
 
 	/*
@@ -4233,12 +4245,12 @@ void resctrl_offline_cpu(unsigned int cpu)
 
 	d = get_mon_domain_from_cpu(cpu, l3);
 	if (d) {
-		if (is_mbm_enabled() && cpu == d->mbm_work_cpu) {
+		if (resctrl_is_mbm_enabled() && cpu == d->mbm_work_cpu) {
 			cancel_delayed_work(&d->mbm_over);
 			mbm_setup_overflow_handler(d, 0, cpu);
 		}
-		if (is_llc_occupancy_enabled() && cpu == d->cqm_work_cpu &&
-		    has_busy_rmid(d)) {
+		if (resctrl_arch_is_llc_occupancy_enabled() &&
+		    cpu == d->cqm_work_cpu && has_busy_rmid(d)) {
 			cancel_delayed_work(&d->cqm_limbo);
 			cqm_setup_limbo_handler(d, 0, cpu);
 		}
-- 
2.39.5

[PATCH v8:for-boris 19/30] x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC

[James Morse]

When BMEC is supported the resctrl event can be configured in a number
of ways. This depends on architecture support. rdt_get_mon_l3_config()
modifies the struct mon_evt and calls resctrl_file_fflags_init() to create
the files that allow the configuration.

Splitting this into separate architecture and filesystem parts would
require the struct mon_evt and resctrl_file_fflags_init() to be exposed.

Instead, add resctrl_arch_is_evt_configurable(), and use this from
resctrl_mon_resource_init() to initialise struct mon_evt and call
resctrl_file_fflags_init()
resctrl_arch_is_evt_configurable() calls rdt_cpu_has() so it doesn't
obviously benefit from being inlined. Putting it in core.c will allow
rdt_cpu_has() to eventually become static.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
---
Changes since v7:
 * Fixed more instances of stale function name in the commit message.

Changes since v6:
 * Fixed stale function name in the commit message.
 * Moved __init around in the function prototypes.

Changes since v4:
 * Moved all the __init changes to a later patch now that the exit gubbins
   comes first.
---
 arch/x86/kernel/cpu/resctrl/core.c    | 15 +++++++++++++++
 arch/x86/kernel/cpu/resctrl/monitor.c | 22 +++++++++++-----------
 include/linux/resctrl.h               |  2 ++
 3 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index eba210db4a7b..6f0d1bbba901 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -830,6 +830,21 @@ bool __init rdt_cpu_has(int flag)
 	return ret;
 }
 
+__init bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt)
+{
+	if (!rdt_cpu_has(X86_FEATURE_BMEC))
+		return false;
+
+	switch (evt) {
+	case QOS_L3_MBM_TOTAL_EVENT_ID:
+		return rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL);
+	case QOS_L3_MBM_LOCAL_EVENT_ID:
+		return rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL);
+	default:
+		return false;
+	}
+}
+
 static __init bool get_mem_config(void)
 {
 	struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_MBA];
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index d883ed56ec90..27d983121b0a 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1202,6 +1202,17 @@ int __init resctrl_mon_resource_init(void)
 
 	l3_mon_evt_init(r);
 
+	if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_TOTAL_EVENT_ID)) {
+		mbm_total_event.configurable = true;
+		resctrl_file_fflags_init("mbm_total_bytes_config",
+					 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
+	}
+	if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_LOCAL_EVENT_ID)) {
+		mbm_local_event.configurable = true;
+		resctrl_file_fflags_init("mbm_local_bytes_config",
+					 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
+	}
+
 	return 0;
 }
 
@@ -1245,17 +1256,6 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 		/* Detect list of bandwidth sources that can be tracked */
 		cpuid_count(0x80000020, 3, &eax, &ebx, &ecx, &edx);
 		hw_res->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
-
-		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL)) {
-			mbm_total_event.configurable = true;
-			resctrl_file_fflags_init("mbm_total_bytes_config",
-						 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
-		}
-		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {
-			mbm_local_event.configurable = true;
-			resctrl_file_fflags_init("mbm_local_bytes_config",
-						 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
-		}
 	}
 
 	r->mon_capable = true;
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index a392480dc4b6..cc76f308e6f3 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -309,6 +309,8 @@ u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
 u32 resctrl_arch_system_num_rmid_idx(void);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
+__init bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt);
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.
-- 
2.39.5

[PATCH v8:for-boris 20/30] x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers

[James Morse]

mon_event_config_{read,write}() are called via IPI and access model
specific registers to do their work.

To support another architecture, this needs abstracting.

Rename mon_event_config_{read,write}() to have a "resctrl_arch_"
prefix, and move their struct mon_config_info parameter into
<linux/resctrl.h>.  This allows another architecture to supply an
implementation of these.

As struct mon_config_info is now exposed globally, give it a 'resctrl_'
prefix. MPAM systems need access to the domain to do this work, add
the resource and domain to struct resctrl_mon_config_info.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Renamed info to config_info.
 * Added description of which fields are read and written in the structure.
 * Clarified comment about which CPU this is called on for both kinds of
   reader.

Changes since v3:
 * Added comments over the read/write helper to explain the type of the void
   pointer.

Changes since v1:
 * [Whitespace only] Re-tabbed struct resctrl_mon_config_info in
   <linux/resctrl.h> to fit the prevailing style.

   Non-functional change.

 * [Commit message only] Reword to align with the actual naming of the
   definitions and destination header file.
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 46 +++++++++++++-------------
 include/linux/resctrl.h                | 31 +++++++++++++++++
 2 files changed, 54 insertions(+), 23 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index eb32fbc3abea..e7d1d8b6983d 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1580,11 +1580,6 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
 	return ret;
 }
 
-struct mon_config_info {
-	u32 evtid;
-	u32 mon_config;
-};
-
 #define INVALID_CONFIG_INDEX   UINT_MAX
 
 /**
@@ -1609,31 +1604,32 @@ static inline unsigned int mon_event_config_index_get(u32 evtid)
 	}
 }
 
-static void mon_event_config_read(void *info)
+void resctrl_arch_mon_event_config_read(void *_config_info)
 {
-	struct mon_config_info *mon_info = info;
+	struct resctrl_mon_config_info *config_info = _config_info;
 	unsigned int index;
 	u64 msrval;
 
-	index = mon_event_config_index_get(mon_info->evtid);
+	index = mon_event_config_index_get(config_info->evtid);
 	if (index == INVALID_CONFIG_INDEX) {
-		pr_warn_once("Invalid event id %d\n", mon_info->evtid);
+		pr_warn_once("Invalid event id %d\n", config_info->evtid);
 		return;
 	}
 	rdmsrl(MSR_IA32_EVT_CFG_BASE + index, msrval);
 
 	/* Report only the valid event configuration bits */
-	mon_info->mon_config = msrval & MAX_EVT_CONFIG_BITS;
+	config_info->mon_config = msrval & MAX_EVT_CONFIG_BITS;
 }
 
-static void mondata_config_read(struct rdt_mon_domain *d, struct mon_config_info *mon_info)
+static void mondata_config_read(struct resctrl_mon_config_info *mon_info)
 {
-	smp_call_function_any(&d->hdr.cpu_mask, mon_event_config_read, mon_info, 1);
+	smp_call_function_any(&mon_info->d->hdr.cpu_mask,
+			      resctrl_arch_mon_event_config_read, mon_info, 1);
 }
 
 static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid)
 {
-	struct mon_config_info mon_info;
+	struct resctrl_mon_config_info mon_info;
 	struct rdt_mon_domain *dom;
 	bool sep = false;
 
@@ -1644,9 +1640,11 @@ static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid
 		if (sep)
 			seq_puts(s, ";");
 
-		memset(&mon_info, 0, sizeof(struct mon_config_info));
+		memset(&mon_info, 0, sizeof(struct resctrl_mon_config_info));
+		mon_info.r = r;
+		mon_info.d = dom;
 		mon_info.evtid = evtid;
-		mondata_config_read(dom, &mon_info);
+		mondata_config_read(&mon_info);
 
 		seq_printf(s, "%d=0x%02x", dom->hdr.id, mon_info.mon_config);
 		sep = true;
@@ -1679,30 +1677,32 @@ static int mbm_local_bytes_config_show(struct kernfs_open_file *of,
 	return 0;
 }
 
-static void mon_event_config_write(void *info)
+void resctrl_arch_mon_event_config_write(void *_config_info)
 {
-	struct mon_config_info *mon_info = info;
+	struct resctrl_mon_config_info *config_info = _config_info;
 	unsigned int index;
 
-	index = mon_event_config_index_get(mon_info->evtid);
+	index = mon_event_config_index_get(config_info->evtid);
 	if (index == INVALID_CONFIG_INDEX) {
-		pr_warn_once("Invalid event id %d\n", mon_info->evtid);
+		pr_warn_once("Invalid event id %d\n", config_info->evtid);
 		return;
 	}
-	wrmsr(MSR_IA32_EVT_CFG_BASE + index, mon_info->mon_config, 0);
+	wrmsr(MSR_IA32_EVT_CFG_BASE + index, config_info->mon_config, 0);
 }
 
 static void mbm_config_write_domain(struct rdt_resource *r,
 				    struct rdt_mon_domain *d, u32 evtid, u32 val)
 {
-	struct mon_config_info mon_info = {0};
+	struct resctrl_mon_config_info mon_info = {0};
 
 	/*
 	 * Read the current config value first. If both are the same then
 	 * no need to write it again.
 	 */
+	mon_info.r = r;
+	mon_info.d = d;
 	mon_info.evtid = evtid;
-	mondata_config_read(d, &mon_info);
+	mondata_config_read(&mon_info);
 	if (mon_info.mon_config == val)
 		return;
 
@@ -1714,7 +1714,7 @@ static void mbm_config_write_domain(struct rdt_resource *r,
 	 * are scoped at the domain level. Writing any of these MSRs
 	 * on one CPU is observed by all the CPUs in the domain.
 	 */
-	smp_call_function_any(&d->hdr.cpu_mask, mon_event_config_write,
+	smp_call_function_any(&d->hdr.cpu_mask, resctrl_arch_mon_event_config_write,
 			      &mon_info, 1);
 
 	/*
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index cc76f308e6f3..90b6563cf532 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -270,6 +270,13 @@ struct resctrl_cpu_defaults {
 	u32 rmid;
 };
 
+struct resctrl_mon_config_info {
+	struct rdt_resource	*r;
+	struct rdt_mon_domain	*d;
+	u32			evtid;
+	u32			mon_config;
+};
+
 /**
  * resctrl_arch_sync_cpu_closid_rmid() - Refresh this CPU's CLOSID and RMID.
  *					 Call via IPI.
@@ -311,6 +318,30 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
 __init bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt);
 
+/**
+ * resctrl_arch_mon_event_config_write() - Write the config for an event.
+ * @config_info: struct resctrl_mon_config_info describing the resource, domain
+ *		 and event.
+ *
+ * Reads resource, domain and eventid from @config_info and writes the
+ * event config_info->mon_config into hardware.
+ *
+ * Called via IPI to reach a CPU that is a member of the specified domain.
+ */
+void resctrl_arch_mon_event_config_write(void *config_info);
+
+/**
+ * resctrl_arch_mon_event_config_read() - Read the config for an event.
+ * @config_info: struct resctrl_mon_config_info describing the resource, domain
+ *		 and event.
+ *
+ * Reads resource, domain and eventid from @config_info and reads the
+ * hardware config value into config_info->mon_config.
+ *
+ * Called via IPI to reach a CPU that is a member of the specified domain.
+ */
+void resctrl_arch_mon_event_config_read(void *config_info);
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.
-- 
2.39.5

[PATCH v8:for-boris 21/30] x86/resctrl: Move mba_mbps_default_event init to filesystem code

[James Morse]

mba_mbps_default_event is initialised base on whether mbm_local or
mbm_total is supported. In the case of both, it is initialised to
mbm_local. mba_mbps_default_event is initialised in core.c's
get_rdt_mon_resources(), while all the readers are in rdtgroup.c.

After this code is split into architecture specific and filesystem code,
get_rdt_mon_resources() remains part of the architecture code, which
would mean mba_mbps_default_event has to be exposed by the filesystem
code.

Move the initialisation to the filesystem's resctrl_mon_resource_init()

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
 arch/x86/kernel/cpu/resctrl/core.c    | 5 -----
 arch/x86/kernel/cpu/resctrl/monitor.c | 5 +++++
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 6f0d1bbba901..b9b74f53b8ee 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -923,11 +923,6 @@ static __init bool get_rdt_mon_resources(void)
 	if (!rdt_mon_features)
 		return false;
 
-	if (resctrl_arch_is_mbm_local_enabled())
-		mba_mbps_default_event = QOS_L3_MBM_LOCAL_EVENT_ID;
-	else if (resctrl_arch_is_mbm_total_enabled())
-		mba_mbps_default_event = QOS_L3_MBM_TOTAL_EVENT_ID;
-
 	return !rdt_get_mon_l3_config(r);
 }
 
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 27d983121b0a..306b06ba32db 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1213,6 +1213,11 @@ int __init resctrl_mon_resource_init(void)
 					 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
 	}
 
+	if (resctrl_arch_is_mbm_local_enabled())
+		mba_mbps_default_event = QOS_L3_MBM_LOCAL_EVENT_ID;
+	else if (resctrl_arch_is_mbm_total_enabled())
+		mba_mbps_default_event = QOS_L3_MBM_TOTAL_EVENT_ID;
+
 	return 0;
 }
 
-- 
2.39.5

[PATCH v8:for-boris 22/30] x86/resctrl: Move mbm_cfg_mask to struct rdt_resource

[James Morse]

The mbm_cfg_mask field lists the bits that user-space can set when
configuring an event. This value is output via the last_cmd_status
file.

Once the filesystem parts of resctrl are moved to live in /fs/, the
struct rdt_hw_resource is inaccessible to the filesystem code. Because
this value is output to user-space, it has to be accessible to the
filesystem code.

Move it to struct rdt_resource.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Rephrased a comment to remove one vendors marketing name for the feature.

Change since v1:
 * Reword comments to avoid being overly arch-specific.
---
 arch/x86/kernel/cpu/resctrl/internal.h | 3 ---
 arch/x86/kernel/cpu/resctrl/monitor.c  | 2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 5 ++---
 include/linux/resctrl.h                | 3 +++
 4 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 4a5996d1e060..725f223ea07b 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -417,8 +417,6 @@ struct msr_param {
  * @msr_update:		Function pointer to update QOS MSRs
  * @mon_scale:		cqm counter * mon_scale = occupancy in bytes
  * @mbm_width:		Monitor width, to detect and correct for overflow.
- * @mbm_cfg_mask:	Bandwidth sources that can be tracked when Bandwidth
- *			Monitoring Event Configuration (BMEC) is supported.
  * @cdp_enabled:	CDP state of this resource
  *
  * Members of this structure are either private to the architecture
@@ -432,7 +430,6 @@ struct rdt_hw_resource {
 	void			(*msr_update)(struct msr_param *m);
 	unsigned int		mon_scale;
 	unsigned int		mbm_width;
-	unsigned int		mbm_cfg_mask;
 	bool			cdp_enabled;
 };
 
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 306b06ba32db..83f90128d768 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1260,7 +1260,7 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 
 		/* Detect list of bandwidth sources that can be tracked */
 		cpuid_count(0x80000020, 3, &eax, &ebx, &ecx, &edx);
-		hw_res->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
+		r->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
 	}
 
 	r->mon_capable = true;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index e7d1d8b6983d..a388ef66ef4c 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1731,7 +1731,6 @@ static void mbm_config_write_domain(struct rdt_resource *r,
 
 static int mon_config_write(struct rdt_resource *r, char *tok, u32 evtid)
 {
-	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
 	char *dom_str = NULL, *id_str;
 	unsigned long dom_id, val;
 	struct rdt_mon_domain *d;
@@ -1758,9 +1757,9 @@ static int mon_config_write(struct rdt_resource *r, char *tok, u32 evtid)
 	}
 
 	/* Value from user cannot be more than the supported set of events */
-	if ((val & hw_res->mbm_cfg_mask) != val) {
+	if ((val & r->mbm_cfg_mask) != val) {
 		rdt_last_cmd_printf("Invalid event configuration: max valid mask is 0x%02x\n",
-				    hw_res->mbm_cfg_mask);
+				    r->mbm_cfg_mask);
 		return -EINVAL;
 	}
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 90b6563cf532..914df24ffe48 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -217,6 +217,8 @@ enum resctrl_schema_fmt {
  * @name:		Name to use in "schemata" file.
  * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
+ * @mbm_cfg_mask:	Bandwidth sources that can be tracked when bandwidth
+ *			monitoring events can be configured.
  * @cdp_capable:	Is the CDP feature available on this resource
  */
 struct rdt_resource {
@@ -233,6 +235,7 @@ struct rdt_resource {
 	char			*name;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
+	unsigned int		mbm_cfg_mask;
 	bool			cdp_capable;
 };
 
-- 
2.39.5

[PATCH v8:for-boris 23/30] x86/resctrl: Add resctrl_arch_ prefix to pseudo lock functions

[James Morse]

resctrl's pseudo lock has some copy-to-cache and measurement
functions that are micro-architecture specific.

For example, pseudo_lock_fn() is not at all portable.

Label these 'resctrl_arch_' so they stay under /arch/x86.
To expose these functions to the filesystem code they need an entry
in a header file, and can't be marked static.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v6:
 * Removed a space.

Changes since v5:
 * Expanded commit message.
---
 arch/x86/include/asm/resctrl.h            |  5 ++++
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 36 ++++++++++++-----------
 2 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 6d4c7ea2c9e3..86407dbde583 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -203,6 +203,11 @@ static inline void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, int evtid
 static inline void resctrl_arch_mon_ctx_free(struct rdt_resource *r, int evtid,
 					     void *ctx) { };
 
+u64 resctrl_arch_get_prefetch_disable_bits(void);
+int resctrl_arch_pseudo_lock_fn(void *_rdtgrp);
+int resctrl_arch_measure_cycles_lat_fn(void *_plr);
+int resctrl_arch_measure_l2_residency(void *_plr);
+int resctrl_arch_measure_l3_residency(void *_plr);
 void resctrl_cpu_detect(struct cpuinfo_x86 *c);
 
 #else
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index 42cc162f7fc9..1f42c1190d26 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -61,7 +61,8 @@ static const struct class pseudo_lock_class = {
 };
 
 /**
- * get_prefetch_disable_bits - prefetch disable bits of supported platforms
+ * resctrl_arch_get_prefetch_disable_bits - prefetch disable bits of supported
+ *                                          platforms
  * @void: It takes no parameters.
  *
  * Capture the list of platforms that have been validated to support
@@ -75,13 +76,13 @@ static const struct class pseudo_lock_class = {
  * in the SDM.
  *
  * When adding a platform here also add support for its cache events to
- * measure_cycles_perf_fn()
+ * resctrl_arch_measure_l*_residency()
  *
  * Return:
  * If platform is supported, the bits to disable hardware prefetchers, 0
  * if platform is not supported.
  */
-static u64 get_prefetch_disable_bits(void)
+u64 resctrl_arch_get_prefetch_disable_bits(void)
 {
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
 	    boot_cpu_data.x86 != 6)
@@ -408,7 +409,7 @@ static void pseudo_lock_free(struct rdtgroup *rdtgrp)
 }
 
 /**
- * pseudo_lock_fn - Load kernel memory into cache
+ * resctrl_arch_pseudo_lock_fn - Load kernel memory into cache
  * @_rdtgrp: resource group to which pseudo-lock region belongs
  *
  * This is the core pseudo-locking flow.
@@ -426,7 +427,7 @@ static void pseudo_lock_free(struct rdtgroup *rdtgrp)
  *
  * Return: 0. Waiter on waitqueue will be woken on completion.
  */
-static int pseudo_lock_fn(void *_rdtgrp)
+int resctrl_arch_pseudo_lock_fn(void *_rdtgrp)
 {
 	struct rdtgroup *rdtgrp = _rdtgrp;
 	struct pseudo_lock_region *plr = rdtgrp->plr;
@@ -712,7 +713,7 @@ int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp)
 	 * Not knowing the bits to disable prefetching implies that this
 	 * platform does not support Cache Pseudo-Locking.
 	 */
-	prefetch_disable_bits = get_prefetch_disable_bits();
+	prefetch_disable_bits = resctrl_arch_get_prefetch_disable_bits();
 	if (prefetch_disable_bits == 0) {
 		rdt_last_cmd_puts("Pseudo-locking not supported\n");
 		return -EINVAL;
@@ -872,7 +873,8 @@ bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d)
 }
 
 /**
- * measure_cycles_lat_fn - Measure cycle latency to read pseudo-locked memory
+ * resctrl_arch_measure_cycles_lat_fn - Measure cycle latency to read
+ *                                      pseudo-locked memory
  * @_plr: pseudo-lock region to measure
  *
  * There is no deterministic way to test if a memory region is cached. One
@@ -885,7 +887,7 @@ bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d)
  *
  * Return: 0. Waiter on waitqueue will be woken on completion.
  */
-static int measure_cycles_lat_fn(void *_plr)
+int resctrl_arch_measure_cycles_lat_fn(void *_plr)
 {
 	struct pseudo_lock_region *plr = _plr;
 	u32 saved_low, saved_high;
@@ -1069,7 +1071,7 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr,
 	return 0;
 }
 
-static int measure_l2_residency(void *_plr)
+int resctrl_arch_measure_l2_residency(void *_plr)
 {
 	struct pseudo_lock_region *plr = _plr;
 	struct residency_counts counts = {0};
@@ -1107,7 +1109,7 @@ static int measure_l2_residency(void *_plr)
 	return 0;
 }
 
-static int measure_l3_residency(void *_plr)
+int resctrl_arch_measure_l3_residency(void *_plr)
 {
 	struct pseudo_lock_region *plr = _plr;
 	struct residency_counts counts = {0};
@@ -1205,14 +1207,14 @@ static int pseudo_lock_measure_cycles(struct rdtgroup *rdtgrp, int sel)
 	plr->cpu = cpu;
 
 	if (sel == 1)
-		thread = kthread_run_on_cpu(measure_cycles_lat_fn, plr,
-					    cpu, "pseudo_lock_measure/%u");
+		thread = kthread_run_on_cpu(resctrl_arch_measure_cycles_lat_fn,
+					    plr, cpu, "pseudo_lock_measure/%u");
 	else if (sel == 2)
-		thread = kthread_run_on_cpu(measure_l2_residency, plr,
-					    cpu, "pseudo_lock_measure/%u");
+		thread = kthread_run_on_cpu(resctrl_arch_measure_l2_residency,
+					    plr, cpu, "pseudo_lock_measure/%u");
 	else if (sel == 3)
-		thread = kthread_run_on_cpu(measure_l3_residency, plr,
-					    cpu, "pseudo_lock_measure/%u");
+		thread = kthread_run_on_cpu(resctrl_arch_measure_l3_residency,
+					    plr, cpu, "pseudo_lock_measure/%u");
 	else
 		goto out;
 
@@ -1307,7 +1309,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 
 	plr->thread_done = 0;
 
-	thread = kthread_run_on_cpu(pseudo_lock_fn, rdtgrp,
+	thread = kthread_run_on_cpu(resctrl_arch_pseudo_lock_fn, rdtgrp,
 				    plr->cpu, "pseudo_lock/%u");
 	if (IS_ERR(thread)) {
 		ret = PTR_ERR(thread);
-- 
2.39.5

[PATCH v8:for-boris 24/30] x86/resctrl: Allow an architecture to disable pseudo lock

[James Morse]

Pseudo-lock relies on knowledge of the micro-architecture to disable
prefetchers etc.

On arm64 these controls are typically secure only, meaning linux can't
access them. Arm's cache-lockdown feature works in a very different
way. Resctrl's pseudo-lock isn't going to be used on arm64 platforms.

Add a Kconfig symbol that can be selected by the architecture. This
enables or disables building of the pseudo_lock.c file, and replaces
the functions with stubs. An additional IS_ENABLED() check is needed
in rdtgroup_mode_write() so that attempting to enable pseudo-lock
reports an "Unknown or unsupported mode" to user-space via the
last_cmd_status file.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v4:
 * "last_cmd file" -> "last_cmd_status file"

Changes since v2:
 * Clarified the commit message as to where the error string is printed.

Changes since v1:
 * [Commit message only] Typo fix:
   s/psuedo/pseudo/g
---
 arch/x86/Kconfig                       |  7 ++++
 arch/x86/kernel/cpu/resctrl/Makefile   |  5 +--
 arch/x86/kernel/cpu/resctrl/internal.h | 49 +++++++++++++++++++++-----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  3 +-
 4 files changed, 53 insertions(+), 11 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index be2c311f5118..1a89574a58f7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -505,6 +505,7 @@ config X86_CPU_RESCTRL
 	depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
 	select KERNFS
 	select PROC_CPU_RESCTRL		if PROC_FS
+	select RESCTRL_FS_PSEUDO_LOCK
 	help
 	  Enable x86 CPU resource control support.
 
@@ -521,6 +522,12 @@ config X86_CPU_RESCTRL
 
 	  Say N if unsure.
 
+config RESCTRL_FS_PSEUDO_LOCK
+	bool
+	help
+	  Software mechanism to pin data in a cache portion using
+	  micro-architecture specific knowledge.
+
 config X86_FRED
 	bool "Flexible Return and Event Delivery"
 	depends on X86_64
diff --git a/arch/x86/kernel/cpu/resctrl/Makefile b/arch/x86/kernel/cpu/resctrl/Makefile
index 4a06c37b9cf1..0c13b0befd8a 100644
--- a/arch/x86/kernel/cpu/resctrl/Makefile
+++ b/arch/x86/kernel/cpu/resctrl/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_X86_CPU_RESCTRL)	+= core.o rdtgroup.o monitor.o
-obj-$(CONFIG_X86_CPU_RESCTRL)	+= ctrlmondata.o pseudo_lock.o
+obj-$(CONFIG_X86_CPU_RESCTRL)		+= core.o rdtgroup.o monitor.o
+obj-$(CONFIG_X86_CPU_RESCTRL)		+= ctrlmondata.o
+obj-$(CONFIG_RESCTRL_FS_PSEUDO_LOCK)	+= pseudo_lock.o
 CFLAGS_pseudo_lock.o = -I$(src)
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 725f223ea07b..8d35bb423aad 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -512,14 +512,6 @@ unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r, struct rdt_ctrl_domain
 				  unsigned long cbm);
 enum rdtgrp_mode rdtgroup_mode_by_closid(int closid);
 int rdtgroup_tasks_assigned(struct rdtgroup *r);
-int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp);
-int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp);
-bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_ctrl_domain *d, unsigned long cbm);
-bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d);
-int rdt_pseudo_lock_init(void);
-void rdt_pseudo_lock_release(void);
-int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp);
-void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp);
 struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu, struct rdt_resource *r);
 struct rdt_mon_domain *get_mon_domain_from_cpu(int cpu, struct rdt_resource *r);
 int closids_supported(void);
@@ -551,4 +543,45 @@ void resctrl_file_fflags_init(const char *config, unsigned long fflags);
 void rdt_staged_configs_clear(void);
 bool closid_allocated(unsigned int closid);
 int resctrl_find_cleanest_closid(void);
+
+#ifdef CONFIG_RESCTRL_FS_PSEUDO_LOCK
+int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp);
+int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp);
+bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_ctrl_domain *d, unsigned long cbm);
+bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d);
+int rdt_pseudo_lock_init(void);
+void rdt_pseudo_lock_release(void);
+int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp);
+void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp);
+#else
+static inline int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_ctrl_domain *d, unsigned long cbm)
+{
+	return false;
+}
+
+static inline bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d)
+{
+	return false;
+}
+
+static inline int rdt_pseudo_lock_init(void) { return 0; }
+static inline void rdt_pseudo_lock_release(void) { }
+static inline int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp) { }
+#endif /* CONFIG_RESCTRL_FS_PSEUDO_LOCK */
+
 #endif /* _ASM_X86_RESCTRL_INTERNAL_H */
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index a388ef66ef4c..e59271515a46 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1453,7 +1453,8 @@ static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of,
 				goto out;
 		}
 		rdtgrp->mode = RDT_MODE_EXCLUSIVE;
-	} else if (!strcmp(buf, "pseudo-locksetup")) {
+	} else if (IS_ENABLED(CONFIG_RESCTRL_FS_PSEUDO_LOCK) &&
+		   !strcmp(buf, "pseudo-locksetup")) {
 		ret = rdtgroup_locksetup_enter(rdtgrp);
 		if (ret)
 			goto out;
-- 
2.39.5

[PATCH v8:for-boris 25/30] x86/resctrl: Make prefetch_disable_bits belong to the arch code

[James Morse]

prefetch_disable_bits is set by rdtgroup_locksetup_enter() from a
value provided by the architecture, but is largely read by other
architecture helpers.

Make resctrl_arch_get_prefetch_disable_bits() set prefetch_disable_bits
so that it can be isolated to arch-code from where the other arch-code
helpers can use its cached-value.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v5:
 * Tweaked the word 'export'.
 * Swapped the second paragraph for Reinette's version.
---
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index 1f42c1190d26..90044a01d000 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -84,6 +84,8 @@ static const struct class pseudo_lock_class = {
  */
 u64 resctrl_arch_get_prefetch_disable_bits(void)
 {
+	prefetch_disable_bits = 0;
+
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
 	    boot_cpu_data.x86 != 6)
 		return 0;
@@ -99,7 +101,8 @@ u64 resctrl_arch_get_prefetch_disable_bits(void)
 		 * 3    DCU IP Prefetcher Disable (R/W)
 		 * 63:4 Reserved
 		 */
-		return 0xF;
+		prefetch_disable_bits = 0xF;
+		break;
 	case INTEL_ATOM_GOLDMONT:
 	case INTEL_ATOM_GOLDMONT_PLUS:
 		/*
@@ -110,10 +113,11 @@ u64 resctrl_arch_get_prefetch_disable_bits(void)
 		 * 2     DCU Hardware Prefetcher Disable (R/W)
 		 * 63:3  Reserved
 		 */
-		return 0x5;
+		prefetch_disable_bits = 0x5;
+		break;
 	}
 
-	return 0;
+	return prefetch_disable_bits;
 }
 
 /**
@@ -713,8 +717,7 @@ int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp)
 	 * Not knowing the bits to disable prefetching implies that this
 	 * platform does not support Cache Pseudo-Locking.
 	 */
-	prefetch_disable_bits = resctrl_arch_get_prefetch_disable_bits();
-	if (prefetch_disable_bits == 0) {
+	if (resctrl_arch_get_prefetch_disable_bits() == 0) {
 		rdt_last_cmd_puts("Pseudo-locking not supported\n");
 		return -EINVAL;
 	}
-- 
2.39.5

[PATCH v8:for-boris 26/30] x86/resctrl: Make resctrl_arch_pseudo_lock_fn() take a plr

[James Morse]

resctrl_arch_pseudo_lock_fn() has architecture specific behaviour,
and takes a struct rdtgroup as an argument.

After the filesystem code moves to /fs/, the definition of struct
rdtgroup will not be available to the architecture code.

The only reason resctrl_arch_pseudo_lock_fn() wants the rdtgroup is
for the CLOSID. Embed that in the pseudo_lock_region as a closid,
and move the definition of struct pseudo_lock_region to resctrl.h.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Change since v1:
 * [Commit message only] Typo fix:
   s/hw_closid/closid/g
---
 arch/x86/include/asm/resctrl.h            |  2 +-
 arch/x86/kernel/cpu/resctrl/internal.h    | 37 ---------------------
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 12 +++----
 include/linux/resctrl.h                   | 39 +++++++++++++++++++++++
 4 files changed, 46 insertions(+), 44 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 86407dbde583..011bf67a1866 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -204,7 +204,7 @@ static inline void resctrl_arch_mon_ctx_free(struct rdt_resource *r, int evtid,
 					     void *ctx) { };
 
 u64 resctrl_arch_get_prefetch_disable_bits(void);
-int resctrl_arch_pseudo_lock_fn(void *_rdtgrp);
+int resctrl_arch_pseudo_lock_fn(void *_plr);
 int resctrl_arch_measure_cycles_lat_fn(void *_plr);
 int resctrl_arch_measure_l2_residency(void *_plr);
 int resctrl_arch_measure_l3_residency(void *_plr);
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 8d35bb423aad..0d13006e920b 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -208,43 +208,6 @@ struct mongroup {
 	u32			rmid;
 };
 
-/**
- * struct pseudo_lock_region - pseudo-lock region information
- * @s:			Resctrl schema for the resource to which this
- *			pseudo-locked region belongs
- * @d:			RDT domain to which this pseudo-locked region
- *			belongs
- * @cbm:		bitmask of the pseudo-locked region
- * @lock_thread_wq:	waitqueue used to wait on the pseudo-locking thread
- *			completion
- * @thread_done:	variable used by waitqueue to test if pseudo-locking
- *			thread completed
- * @cpu:		core associated with the cache on which the setup code
- *			will be run
- * @line_size:		size of the cache lines
- * @size:		size of pseudo-locked region in bytes
- * @kmem:		the kernel memory associated with pseudo-locked region
- * @minor:		minor number of character device associated with this
- *			region
- * @debugfs_dir:	pointer to this region's directory in the debugfs
- *			filesystem
- * @pm_reqs:		Power management QoS requests related to this region
- */
-struct pseudo_lock_region {
-	struct resctrl_schema	*s;
-	struct rdt_ctrl_domain	*d;
-	u32			cbm;
-	wait_queue_head_t	lock_thread_wq;
-	int			thread_done;
-	int			cpu;
-	unsigned int		line_size;
-	unsigned int		size;
-	void			*kmem;
-	unsigned int		minor;
-	struct dentry		*debugfs_dir;
-	struct list_head	pm_reqs;
-};
-
 /**
  * struct rdtgroup - store rdtgroup's data in resctrl file system.
  * @kn:				kernfs node
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index 90044a01d000..01fa7890b43f 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -414,7 +414,7 @@ static void pseudo_lock_free(struct rdtgroup *rdtgrp)
 
 /**
  * resctrl_arch_pseudo_lock_fn - Load kernel memory into cache
- * @_rdtgrp: resource group to which pseudo-lock region belongs
+ * @_plr: the pseudo-lock region descriptor
  *
  * This is the core pseudo-locking flow.
  *
@@ -431,10 +431,9 @@ static void pseudo_lock_free(struct rdtgroup *rdtgrp)
  *
  * Return: 0. Waiter on waitqueue will be woken on completion.
  */
-int resctrl_arch_pseudo_lock_fn(void *_rdtgrp)
+int resctrl_arch_pseudo_lock_fn(void *_plr)
 {
-	struct rdtgroup *rdtgrp = _rdtgrp;
-	struct pseudo_lock_region *plr = rdtgrp->plr;
+	struct pseudo_lock_region *plr = _plr;
 	u32 rmid_p, closid_p;
 	unsigned long i;
 	u64 saved_msr;
@@ -494,7 +493,8 @@ int resctrl_arch_pseudo_lock_fn(void *_rdtgrp)
 	 * pseudo-locked followed by reading of kernel memory to load it
 	 * into the cache.
 	 */
-	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, rdtgrp->closid);
+	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, plr->closid);
+
 	/*
 	 * Cache was flushed earlier. Now access kernel memory to read it
 	 * into cache region associated with just activated plr->closid.
@@ -1312,7 +1312,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 
 	plr->thread_done = 0;
 
-	thread = kthread_run_on_cpu(resctrl_arch_pseudo_lock_fn, rdtgrp,
+	thread = kthread_run_on_cpu(resctrl_arch_pseudo_lock_fn, plr,
 				    plr->cpu, "pseudo_lock/%u");
 	if (IS_ERR(thread)) {
 		ret = PTR_ERR(thread);
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 914df24ffe48..226cc5c0d765 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -58,6 +58,45 @@ enum resctrl_conf_type {
 
 #define CDP_NUM_TYPES	(CDP_DATA + 1)
 
+/*
+ * struct pseudo_lock_region - pseudo-lock region information
+ * @s:			Resctrl schema for the resource to which this
+ *			pseudo-locked region belongs
+ * @closid:		The closid that this pseudo-locked region uses
+ * @d:			RDT domain to which this pseudo-locked region
+ *			belongs
+ * @cbm:		bitmask of the pseudo-locked region
+ * @lock_thread_wq:	waitqueue used to wait on the pseudo-locking thread
+ *			completion
+ * @thread_done:	variable used by waitqueue to test if pseudo-locking
+ *			thread completed
+ * @cpu:		core associated with the cache on which the setup code
+ *			will be run
+ * @line_size:		size of the cache lines
+ * @size:		size of pseudo-locked region in bytes
+ * @kmem:		the kernel memory associated with pseudo-locked region
+ * @minor:		minor number of character device associated with this
+ *			region
+ * @debugfs_dir:	pointer to this region's directory in the debugfs
+ *			filesystem
+ * @pm_reqs:		Power management QoS requests related to this region
+ */
+struct pseudo_lock_region {
+	struct resctrl_schema	*s;
+	u32			closid;
+	struct rdt_ctrl_domain	*d;
+	u32			cbm;
+	wait_queue_head_t	lock_thread_wq;
+	int			thread_done;
+	int			cpu;
+	unsigned int		line_size;
+	unsigned int		size;
+	void			*kmem;
+	unsigned int		minor;
+	struct dentry		*debugfs_dir;
+	struct list_head	pm_reqs;
+};
+
 /**
  * struct resctrl_staged_config - parsed configuration to be applied
  * @new_ctrl:		new ctrl value to be loaded
-- 
2.39.5

[PATCH v8:for-boris 27/30] x86/resctrl: Move RFTYPE flags to be managed by resctrl

[James Morse]

resctrl_file_fflags_init() is called from the architecture specific code
to make the 'thread_throttle_mode' file visible. The architecture specific
code has already set the membw.throttle_mode in the rdt_resource.

This forces the RFTYPE flags used by resctrl to be exposed to the
architecture specific code.

This doesn't need to be specific to the architecture, the throttle_mode
can be used by resctrl to determine if the 'thread_throttle_mode' file
should be visible. This allows the RFTYPE flags to be private to resctrl.

Add thread_throttle_mode_init(), and use it to call
resctrl_file_fflags_init() from resctrl_init(). This avoids
publishing an extra function between the architecture and filesystem
code.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v6:
 * Refer to resctrl_init() in the commit message.
 * Remove a space.

Changes since v5:
 * Added checking for SMBA.
 * Added printing of undefined to rdt_thread_throttle_mode_show().
 * Major juggling around commit 2937f9c361f7 ("x86/resctrl: Introduce resctrl_file_fflags_init() to initialize fflags")
 * Dropped tags, split patch
---
 arch/x86/kernel/cpu/resctrl/core.c     |  3 ---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 12 ++++++++++++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index b9b74f53b8ee..e590dd347fa7 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -227,9 +227,6 @@ static __init bool __get_mem_config_intel(struct rdt_resource *r)
 	else
 		r->membw.throttle_mode = THREAD_THROTTLE_MAX;
 
-	resctrl_file_fflags_init("thread_throttle_mode",
-				 RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
-
 	r->alloc_capable = true;
 
 	return true;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index e59271515a46..58feba3feefd 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2064,6 +2064,16 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
 	return NULL;
 }
 
+static void thread_throttle_mode_init(void)
+{
+	struct rdt_resource *r_mba;
+
+	r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
+	if (r_mba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
+		resctrl_file_fflags_init("thread_throttle_mode",
+					 RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
+}
+
 void resctrl_file_fflags_init(const char *config, unsigned long fflags)
 {
 	struct rftype *rft;
@@ -4277,6 +4287,8 @@ int __init resctrl_init(void)
 
 	rdtgroup_setup_default();
 
+	thread_throttle_mode_init();
+
 	ret = resctrl_mon_resource_init();
 	if (ret)
 		return ret;
-- 
2.39.5

[PATCH v8:for-boris 28/30] x86/resctrl: Handle throttle_mode for SMBA resources

[James Morse]

Now that the visibility of throttle_mode is being managed by resctrl, it
should consider resources other than MBA that may have a throttle_mode.
SMBA is one such resource.

Extend thread_throttle_mode_init() to check SMBA for a throttle_mode.

Adding support for multiple resources means it is possible for a platform
with both MBA and SMBA, but an undefined throttle_mode on one of them
to make the file visible.

Add the 'undefined' case to rdt_thread_throttle_mode_show().

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
---
Changes since v6:
 * Refer to thread_throttle_mode_init() in the commit message.

Changes since v5:
 * This change split out of the previous patch.
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 33 +++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 58feba3feefd..5fc60c9ce28f 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1188,10 +1188,19 @@ static int rdt_thread_throttle_mode_show(struct kernfs_open_file *of,
 	struct resctrl_schema *s = of->kn->parent->priv;
 	struct rdt_resource *r = s->res;
 
-	if (r->membw.throttle_mode == THREAD_THROTTLE_PER_THREAD)
+	switch (r->membw.throttle_mode) {
+	case THREAD_THROTTLE_PER_THREAD:
 		seq_puts(seq, "per-thread\n");
-	else
+		return 0;
+	case THREAD_THROTTLE_MAX:
 		seq_puts(seq, "max\n");
+		return 0;
+	case THREAD_THROTTLE_UNDEFINED:
+		seq_puts(seq, "undefined\n");
+		return 0;
+	}
+
+	WARN_ON_ONCE(1);
 
 	return 0;
 }
@@ -2066,12 +2075,24 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
 
 static void thread_throttle_mode_init(void)
 {
-	struct rdt_resource *r_mba;
+	enum membw_throttle_mode throttle_mode = THREAD_THROTTLE_UNDEFINED;
+	struct rdt_resource *r_mba, *r_smba;
 
 	r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
-	if (r_mba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
-		resctrl_file_fflags_init("thread_throttle_mode",
-					 RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
+	if (r_mba->alloc_capable &&
+	    r_mba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
+		throttle_mode = r_mba->membw.throttle_mode;
+
+	r_smba = resctrl_arch_get_resource(RDT_RESOURCE_SMBA);
+	if (r_smba->alloc_capable &&
+	    r_smba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
+		throttle_mode = r_smba->membw.throttle_mode;
+
+	if (throttle_mode == THREAD_THROTTLE_UNDEFINED)
+		return;
+
+	resctrl_file_fflags_init("thread_throttle_mode",
+				 RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
 }
 
 void resctrl_file_fflags_init(const char *config, unsigned long fflags)
-- 
2.39.5

[PATCH v8:for-boris 29/30] x86/resctrl: Move get_config_index() to a header

[James Morse]

get_config_index() is used by the architecture specific code to map a
CLOSID+type pair to an index in the configuration arrays.

MPAM needs to do this too to preserve the ABI to user-space, there is
no reason to do it differently.

Move the helper to a header file to allow all architectures that either
use or emulate CDP to use the same pattern of CLOSID values. Moving
this to a header file means it must be marked inline, which matches
the existing compiler choice for this static function.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
---
Changes since v6:
 * Expanded the last paragraph of the commit message.

Changes since v1:
 * Reindent resctrl_get_config_index() as per coding-style.rst rules.
---
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 19 +++----------------
 include/linux/resctrl.h                   | 15 +++++++++++++++
 2 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 1ecc93282b7d..0a0ac5f6112e 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -287,25 +287,12 @@ static int parse_line(char *line, struct resctrl_schema *s,
 	return -EINVAL;
 }
 
-static u32 get_config_index(u32 closid, enum resctrl_conf_type type)
-{
-	switch (type) {
-	default:
-	case CDP_NONE:
-		return closid;
-	case CDP_CODE:
-		return closid * 2 + 1;
-	case CDP_DATA:
-		return closid * 2;
-	}
-}
-
 int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_ctrl_domain *d,
 			    u32 closid, enum resctrl_conf_type t, u32 cfg_val)
 {
 	struct rdt_hw_ctrl_domain *hw_dom = resctrl_to_arch_ctrl_dom(d);
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
-	u32 idx = get_config_index(closid, t);
+	u32 idx = resctrl_get_config_index(closid, t);
 	struct msr_param msr_param;
 
 	if (!cpumask_test_cpu(smp_processor_id(), &d->hdr.cpu_mask))
@@ -342,7 +329,7 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid)
 			if (!cfg->have_new_ctrl)
 				continue;
 
-			idx = get_config_index(closid, t);
+			idx = resctrl_get_config_index(closid, t);
 			if (cfg->new_ctrl == hw_dom->ctrl_val[idx])
 				continue;
 			hw_dom->ctrl_val[idx] = cfg->new_ctrl;
@@ -462,7 +449,7 @@ u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_ctrl_domain *d,
 			    u32 closid, enum resctrl_conf_type type)
 {
 	struct rdt_hw_ctrl_domain *hw_dom = resctrl_to_arch_ctrl_dom(d);
-	u32 idx = get_config_index(closid, type);
+	u32 idx = resctrl_get_config_index(closid, type);
 
 	return hw_dom->ctrl_val[idx];
 }
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 226cc5c0d765..880351ca3dfc 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -384,6 +384,21 @@ void resctrl_arch_mon_event_config_write(void *config_info);
  */
 void resctrl_arch_mon_event_config_read(void *config_info);
 
+/* For use by arch code to remap resctrl's smaller CDP CLOSID range */
+static inline u32 resctrl_get_config_index(u32 closid,
+					   enum resctrl_conf_type type)
+{
+	switch (type) {
+	default:
+	case CDP_NONE:
+		return closid;
+	case CDP_CODE:
+		return closid * 2 + 1;
+	case CDP_DATA:
+		return closid * 2;
+	}
+}
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.
-- 
2.39.5

[PATCH v8:for-boris 30/30] x86/resctrl: Move get_{mon,ctrl}_domain_from_cpu() to live with their callers

[James Morse]

Each of get_{mon,ctrl}_domain_from_cpu() only has one caller.

Once the filesystem code is moved to /fs/, there is no equivalent to
core.c.

Move these functions to each live next to their caller. This allows
them to be made static and the header file entries to be removed.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
---
Changes since v7:
 * Typo: teh->the

Changes since v6:
 * This patch replaces one that moved these to a header, any arch code
   will need its own way of finding the domain to online/offline from
   a cpu number.
---
 arch/x86/kernel/cpu/resctrl/core.c     | 30 --------------------------
 arch/x86/kernel/cpu/resctrl/internal.h |  2 --
 arch/x86/kernel/cpu/resctrl/monitor.c  | 16 ++++++++++++++
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 16 ++++++++++++++
 4 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index e590dd347fa7..cf29681d01e0 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -347,36 +347,6 @@ static void cat_wrmsr(struct msr_param *m)
 		wrmsrl(hw_res->msr_base + i, hw_dom->ctrl_val[i]);
 }
 
-struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu, struct rdt_resource *r)
-{
-	struct rdt_ctrl_domain *d;
-
-	lockdep_assert_cpus_held();
-
-	list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
-		/* Find the domain that contains this CPU */
-		if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask))
-			return d;
-	}
-
-	return NULL;
-}
-
-struct rdt_mon_domain *get_mon_domain_from_cpu(int cpu, struct rdt_resource *r)
-{
-	struct rdt_mon_domain *d;
-
-	lockdep_assert_cpus_held();
-
-	list_for_each_entry(d, &r->mon_domains, hdr.list) {
-		/* Find the domain that contains this CPU */
-		if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask))
-			return d;
-	}
-
-	return NULL;
-}
-
 u32 resctrl_arch_get_num_closid(struct rdt_resource *r)
 {
 	return resctrl_to_arch_res(r)->num_closid;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 0d13006e920b..c44c5b496355 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -475,8 +475,6 @@ unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r, struct rdt_ctrl_domain
 				  unsigned long cbm);
 enum rdtgrp_mode rdtgroup_mode_by_closid(int closid);
 int rdtgroup_tasks_assigned(struct rdtgroup *r);
-struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu, struct rdt_resource *r);
-struct rdt_mon_domain *get_mon_domain_from_cpu(int cpu, struct rdt_resource *r);
 int closids_supported(void);
 void closid_free(int closid);
 int alloc_rmid(u32 closid);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 83f90128d768..a93ed7d2a160 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -718,6 +718,22 @@ void mon_event_count(void *info)
 		rr->err = 0;
 }
 
+static struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu,
+							struct rdt_resource *r)
+{
+	struct rdt_ctrl_domain *d;
+
+	lockdep_assert_cpus_held();
+
+	list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
+		/* Find the domain that contains this CPU */
+		if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask))
+			return d;
+	}
+
+	return NULL;
+}
+
 /*
  * Feedback loop for MBA software controller (mba_sc)
  *
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 5fc60c9ce28f..c6274d40b217 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4257,6 +4257,22 @@ static void clear_childcpus(struct rdtgroup *r, unsigned int cpu)
 	}
 }
 
+static struct rdt_mon_domain *get_mon_domain_from_cpu(int cpu,
+						      struct rdt_resource *r)
+{
+	struct rdt_mon_domain *d;
+
+	lockdep_assert_cpus_held();
+
+	list_for_each_entry(d, &r->mon_domains, hdr.list) {
+		/* Find the domain that contains this CPU */
+		if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask))
+			return d;
+	}
+
+	return NULL;
+}
+
 void resctrl_offline_cpu(unsigned int cpu)
 {
 	struct rdt_resource *l3 = resctrl_arch_get_resource(RDT_RESOURCE_L3);
-- 
2.39.5

Re: [PATCH v8:for-boris 00/30] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[Moger, Babu]

Hi All,

On 3/11/2025 1:36 PM, James Morse wrote:
> Changes since v7?:
>   * Series split to the first 30 patches, requested by Boris.
>   * Fixed stale function names, definitions/declartions and typos.
>   * Dropped the use of the default ctrlval helper in cache_alloc_hsw_probe()
> 
> As ever, changes are noted on each patch.
> ---
> This series renames functions and moves code around. With the
> exception of invalid configurations for the configurable-events, there should
> be no changes in behaviour caused by this series. It is now possible for
> throttle_mode to report 'undefined', but no known platform will do this.
> 
> The driving pattern is to make things like struct rdtgroup private to resctrl.
> Features like pseudo-lock aren't going to work on arm64, the ability to disable
> it at compile time is added.
> 
> All this is to allow the filesystem portions of resctrl to be moved to live in /fs/,
> which allows resctrl to be supported by other architecture, such as arm64's MPAM.
> (What's MPAM? See the cover letter of the first series. [1])
> 
> This series is based on v6.14-rc3 and can be retrieved from:
> https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/move_to_fs/v8_for_boris
> 
> As ever - bugs welcome,
> Thanks,
> 
> James
> 
> [v7] https://lore.kernel.org/lkml/20250228195913.24895-1-james.morse@arm.com
> [v6] https://lore.kernel.org/lkml/20250207181823.6378-1-james.morse@arm.com/
> [v5] https://lore.kernel.org/r/20241004180347.19985-1-james.morse@arm.com
> [v4] https://lore.kernel.org/all/20240802172853.22529-1-james.morse@arm.com/
> [v3] https://lore.kernel.org/r/20240614150033.10454-1-james.morse@arm.com
> [v2] https://lore.kernel.org/r/20240426150537.8094-1-Dave.Martin@arm.com
> [v1] https://lore.kernel.org/r/20240321165106.31602-1-james.morse@arm.com
> [1] https://lore.kernel.org/lkml/20201030161120.227225-1-james.morse@arm.com/
> 
> James Morse (30):
>    x86/resctrl: Fix allocation of cleanest CLOSID on platforms with no
>      monitors
>    x86/resctrl: Add a helper to avoid reaching into the arch code
>      resource list
>    x86/resctrl: Remove fflags from struct rdt_resource
>    x86/resctrl: Use schema type to determine how to parse schema values
>    x86/resctrl: Use schema type to determine the schema format string
>    x86/resctrl: Remove data_width and the tabular format
>    x86/resctrl: Add max_bw to struct resctrl_membw
>    x86/resctrl: Generate default_ctrl instead of sharing it
>    x86/resctrl: Add helper for setting CPU default properties
>    x86/resctrl: Remove rdtgroup from update_cpu_closid_rmid()
>    x86/resctrl: Expose resctrl fs's init function to the rest of the
>      kernel
>    x86/resctrl: Move rdt_find_domain() to be visible to arch and fs code
>    x86/resctrl: Move resctrl types to a separate header
>    x86/resctrl: Add an arch helper to reset one resource
>    x86/resctrl: Move monitor exit work to a resctrl exit call
>    x86/resctrl: Move monitor init work to a resctrl init call
>    x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkers
>    x86/resctrl: Move the is_mbm_*_enabled() helpers to asm/resctrl.h
>    x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC
>    x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers
>    x86/resctrl: Move mba_mbps_default_event init to filesystem code
>    x86/resctrl: Move mbm_cfg_mask to struct rdt_resource
>    x86/resctrl: Add resctrl_arch_ prefix to pseudo lock functions
>    x86/resctrl: Allow an architecture to disable pseudo lock
>    x86/resctrl: Make prefetch_disable_bits belong to the arch code
>    x86/resctrl: Make resctrl_arch_pseudo_lock_fn() take a plr
>    x86/resctrl: Move RFTYPE flags to be managed by resctrl
>    x86/resctrl: Handle throttle_mode for SMBA resources
>    x86/resctrl: Move get_config_index() to a header
>    x86/resctrl: Move get_{mon,ctrl}_domain_from_cpu() to live with their
>      callers
> 
>   MAINTAINERS                               |   1 +
>   arch/x86/Kconfig                          |   7 +
>   arch/x86/include/asm/resctrl.h            |  36 ++-
>   arch/x86/kernel/cpu/resctrl/Makefile      |   5 +-
>   arch/x86/kernel/cpu/resctrl/core.c        | 181 ++++----------
>   arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  93 ++++---
>   arch/x86/kernel/cpu/resctrl/internal.h    | 201 ++++-----------
>   arch/x86/kernel/cpu/resctrl/monitor.c     | 119 ++++++---
>   arch/x86/kernel/cpu/resctrl/pseudo_lock.c |  55 +++--
>   arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 284 ++++++++++++++++------
>   include/linux/resctrl.h                   | 212 ++++++++++++++--
>   include/linux/resctrl_types.h             |  54 ++++
>   12 files changed, 769 insertions(+), 479 deletions(-)
>   create mode 100644 include/linux/resctrl_types.h
> 

Tested the v8 series again and also already reviewed the patches.

Tested-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>

Re: [PATCH v8:for-boris 00/30] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[Luck, Tony]

On Tue, Mar 11, 2025 at 06:36:45PM +0000, James Morse wrote:
> Changes since v7?:
>  * Series split to the first 30 patches, requested by Boris.
>  * Fixed stale function names, definitions/declartions and typos.
>  * Dropped the use of the default ctrlval helper in cache_alloc_hsw_probe()
> 
> As ever, changes are noted on each patch.
> ---
> This series renames functions and moves code around. With the
> exception of invalid configurations for the configurable-events, there should
> be no changes in behaviour caused by this series. It is now possible for
> throttle_mode to report 'undefined', but no known platform will do this.
> 
> The driving pattern is to make things like struct rdtgroup private to resctrl.
> Features like pseudo-lock aren't going to work on arm64, the ability to disable
> it at compile time is added.
> 
> All this is to allow the filesystem portions of resctrl to be moved to live in /fs/,
> which allows resctrl to be supported by other architecture, such as arm64's MPAM.
> (What's MPAM? See the cover letter of the first series. [1])
> 
> This series is based on v6.14-rc3 and can be retrieved from:
> https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/move_to_fs/v8_for_boris
> 
> As ever - bugs welcome,
> Thanks,
> 
> James

Built, booted, and ran tools/testing/selftests/resctrl/resctrl_tests
successfully on Intel Icelake.

-Tony

Re: [PATCH v8:for-boris 08/30] x86/resctrl: Generate default_ctrl instead of sharing it

[Reinette Chatre]

Hi James,

On 3/11/25 11:36 AM, James Morse wrote:
> The struct rdt_resource default_ctrl is used by both the architecture
> code for resetting the hardware controls, and sometimes by the
> filesystem code as the default value for the schema, unless the
> bandwidth software controller is in use.
> 
> Having the default exposed by the architecture code causes unnecessary
> duplication for each architecture as the default value must be specified,
> but can be derived from other schema properties. Now that the
> maximum bandwidth is explicitly described, resctrl can derive the default
> value from the schema format and the other resource properties.
> 
> Signed-off-by: James Morse <james.morse@arm.com>
> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
> Tested-by: Peter Newman <peternewman@google.com>
> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
> Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
> Tested-by: Babu Moger <babu.moger@amd.com>
> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
> Reviewed-by: Tony Luck <tony.luck@intel.com>
> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
> ---

Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>

Reinette

Re: [PATCH v8:for-boris 22/30] x86/resctrl: Move mbm_cfg_mask to struct rdt_resource

[Reinette Chatre]

Hi James,

On 3/11/25 11:37 AM, James Morse wrote:
> The mbm_cfg_mask field lists the bits that user-space can set when
> configuring an event. This value is output via the last_cmd_status
> file.
> 
> Once the filesystem parts of resctrl are moved to live in /fs/, the
> struct rdt_hw_resource is inaccessible to the filesystem code. Because
> this value is output to user-space, it has to be accessible to the
> filesystem code.
> 
> Move it to struct rdt_resource.
> 
> Signed-off-by: James Morse <james.morse@arm.com>
> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
> Tested-by: Peter Newman <peternewman@google.com>
> Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
> Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
> Tested-by: Babu Moger <babu.moger@amd.com>
> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
> Reviewed-by: Tony Luck <tony.luck@intel.com>
> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
> Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
> ---

Nit: checkpatch.pl warns about the duplicate signature for Fenghua.

Reinette

Re: [PATCH v8:for-boris 00/30] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[Reinette Chatre]

Hi James and Boris,

On 3/11/25 11:36 AM, James Morse wrote:
> Changes since v7?:
>  * Series split to the first 30 patches, requested by Boris.
>  * Fixed stale function names, definitions/declartions and typos.
>  * Dropped the use of the default ctrlval helper in cache_alloc_hsw_probe()
> 
> As ever, changes are noted on each patch.
> ---
> This series renames functions and moves code around. With the
> exception of invalid configurations for the configurable-events, there should
> be no changes in behaviour caused by this series. It is now possible for
> throttle_mode to report 'undefined', but no known platform will do this.
> 
> The driving pattern is to make things like struct rdtgroup private to resctrl.
> Features like pseudo-lock aren't going to work on arm64, the ability to disable
> it at compile time is added.
> 
> All this is to allow the filesystem portions of resctrl to be moved to live in /fs/,
> which allows resctrl to be supported by other architecture, such as arm64's MPAM.
> (What's MPAM? See the cover letter of the first series. [1])
> 
> This series is based on v6.14-rc3 and can be retrieved from:
> https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/move_to_fs/v8_for_boris
> 
> As ever - bugs welcome,
> Thanks,
> 
> James

This series looks good to me (just one nit in patch #22). All patches should have
my "Reviewed-by" tag now. 

This series passed my testing with only a 0-day report outstanding. Since v7 passed a
0-day check I do not expect there to be issues with this. I believe 0-day will also
automatically run a check when patches land in tip.

Thank you very much.

Reinette

Re: [PATCH v8:for-boris 22/30] x86/resctrl: Move mbm_cfg_mask to struct rdt_resource

[Borislav Petkov]

On Tue, Mar 11, 2025 at 09:47:38PM -0700, Reinette Chatre wrote:
> Nit: checkpatch.pl warns about the duplicate signature for Fenghua.

My patch massaging script whacked it already.

:-)

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette

RE: [PATCH v8:for-boris 00/30] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[Shaopeng Tan (Fujitsu)]

Hello

I ran tools/tests/selftests/resctrl on Intel(R) Xeon(R) Gold 6338T CPU @ 2.10GHz,
and reviewed all the patches.

Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>

Best regards,
Shaopeng TAN

> -----Original Message-----
> From: James Morse <james.morse@arm.com>
> Sent: Wednesday, March 12, 2025 3:37 AM
> To: x86@kernel.org; linux-kernel@vger.kernel.org
> Cc: Reinette Chatre <reinette.chatre@intel.com>; Thomas Gleixner
> <tglx@linutronix.de>; Ingo Molnar <mingo@redhat.com>; Borislav Petkov
> <bp@alien8.de>; H Peter Anvin <hpa@zytor.com>; Babu Moger
> <Babu.Moger@amd.com>; James Morse <james.morse@arm.com>;
> shameerali.kolothum.thodi@huawei.com; D Scott Phillips OS
> <scott@os.amperecomputing.com>; carl@os.amperecomputing.com;
> lcherian@marvell.com; bobo.shaobowang@huawei.com; Tan, Shaopeng/譚 紹
> 鵬 <tan.shaopeng@fujitsu.com>; baolin.wang@linux.alibaba.com; Jamie Iles
> <quic_jiles@quicinc.com>; Xin Hao <xhao@linux.alibaba.com>;
> peternewman@google.com; dfustini@baylibre.com; amitsinght@marvell.com;
> David Hildenbrand <david@redhat.com>; Rex Nie
> <rex.nie@jaguarmicro.com>; Dave Martin <dave.martin@arm.com>; Koba Ko
> <kobak@nvidia.com>; Shanker Donthineni <sdonthineni@nvidia.com>;
> fenghuay@nvidia.com
> Subject: [PATCH v8:for-boris 00/30] x86/resctrl: Move the resctrl filesystem
> code to /fs/resctrl
> 
> Changes since v7?:
>  * Series split to the first 30 patches, requested by Boris.
>  * Fixed stale function names, definitions/declartions and typos.
>  * Dropped the use of the default ctrlval helper in cache_alloc_hsw_probe()
> 
> As ever, changes are noted on each patch.
> ---
> This series renames functions and moves code around. With the exception of
> invalid configurations for the configurable-events, there should be no changes
> in behaviour caused by this series. It is now possible for throttle_mode to report
> 'undefined', but no known platform will do this.
> 
> The driving pattern is to make things like struct rdtgroup private to resctrl.
> Features like pseudo-lock aren't going to work on arm64, the ability to disable it
> at compile time is added.
> 
> All this is to allow the filesystem portions of resctrl to be moved to live in /fs/,
> which allows resctrl to be supported by other architecture, such as arm64's
> MPAM.
> (What's MPAM? See the cover letter of the first series. [1])
> 
> This series is based on v6.14-rc3 and can be retrieved from:
> https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git
> mpam/move_to_fs/v8_for_boris
> 
> As ever - bugs welcome,
> Thanks,
> 
> James
> 
> [v7]
> https://lore.kernel.org/lkml/20250228195913.24895-1-james.morse@arm.com
> [v6]
> https://lore.kernel.org/lkml/20250207181823.6378-1-james.morse@arm.com/
> [v5]
> https://lore.kernel.org/r/20241004180347.19985-1-james.morse@arm.com
> [v4]
> https://lore.kernel.org/all/20240802172853.22529-1-james.morse@arm.com/
> [v3]
> https://lore.kernel.org/r/20240614150033.10454-1-james.morse@arm.com
> [v2] https://lore.kernel.org/r/20240426150537.8094-1-Dave.Martin@arm.com
> [v1]
> https://lore.kernel.org/r/20240321165106.31602-1-james.morse@arm.com
> [1]
> https://lore.kernel.org/lkml/20201030161120.227225-1-james.morse@arm.co
> m/
> 
> James Morse (30):
>   x86/resctrl: Fix allocation of cleanest CLOSID on platforms with no
>     monitors
>   x86/resctrl: Add a helper to avoid reaching into the arch code
>     resource list
>   x86/resctrl: Remove fflags from struct rdt_resource
>   x86/resctrl: Use schema type to determine how to parse schema values
>   x86/resctrl: Use schema type to determine the schema format string
>   x86/resctrl: Remove data_width and the tabular format
>   x86/resctrl: Add max_bw to struct resctrl_membw
>   x86/resctrl: Generate default_ctrl instead of sharing it
>   x86/resctrl: Add helper for setting CPU default properties
>   x86/resctrl: Remove rdtgroup from update_cpu_closid_rmid()
>   x86/resctrl: Expose resctrl fs's init function to the rest of the
>     kernel
>   x86/resctrl: Move rdt_find_domain() to be visible to arch and fs code
>   x86/resctrl: Move resctrl types to a separate header
>   x86/resctrl: Add an arch helper to reset one resource
>   x86/resctrl: Move monitor exit work to a resctrl exit call
>   x86/resctrl: Move monitor init work to a resctrl init call
>   x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkers
>   x86/resctrl: Move the is_mbm_*_enabled() helpers to asm/resctrl.h
>   x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC
>   x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers
>   x86/resctrl: Move mba_mbps_default_event init to filesystem code
>   x86/resctrl: Move mbm_cfg_mask to struct rdt_resource
>   x86/resctrl: Add resctrl_arch_ prefix to pseudo lock functions
>   x86/resctrl: Allow an architecture to disable pseudo lock
>   x86/resctrl: Make prefetch_disable_bits belong to the arch code
>   x86/resctrl: Make resctrl_arch_pseudo_lock_fn() take a plr
>   x86/resctrl: Move RFTYPE flags to be managed by resctrl
>   x86/resctrl: Handle throttle_mode for SMBA resources
>   x86/resctrl: Move get_config_index() to a header
>   x86/resctrl: Move get_{mon,ctrl}_domain_from_cpu() to live with their
>     callers
> 
>  MAINTAINERS                               |   1 +
>  arch/x86/Kconfig                          |   7 +
>  arch/x86/include/asm/resctrl.h            |  36 ++-
>  arch/x86/kernel/cpu/resctrl/Makefile      |   5 +-
>  arch/x86/kernel/cpu/resctrl/core.c        | 181 ++++----------
>  arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  93 ++++---
>  arch/x86/kernel/cpu/resctrl/internal.h    | 201 ++++-----------
>  arch/x86/kernel/cpu/resctrl/monitor.c     | 119 ++++++---
>  arch/x86/kernel/cpu/resctrl/pseudo_lock.c |  55 +++--
>  arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 284
> ++++++++++++++++------
>  include/linux/resctrl.h                   | 212 ++++++++++++++--
>  include/linux/resctrl_types.h             |  54 ++++
>  12 files changed, 769 insertions(+), 479 deletions(-)  create mode 100644
> include/linux/resctrl_types.h
> 
> --
> 2.39.5

[tip: x86/cache] x86/resctrl: Move get_{mon,ctrl}_domain_from_cpu() to live with their callers

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     823beb31e55673bf2fd21374e095eec73a761ee7
Gitweb:        https://git.kernel.org/tip/823beb31e55673bf2fd21374e095eec73a761ee7
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:15 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:58 +01:00

x86/resctrl: Move get_{mon,ctrl}_domain_from_cpu() to live with their callers

Each of get_{mon,ctrl}_domain_from_cpu() only has one caller.

Once the filesystem code is moved to /fs/, there is no equivalent to
core.c.

Move these functions to each live next to their caller. This allows
them to be made static and the header file entries to be removed.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-31-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c     | 30 +-------------------------
 arch/x86/kernel/cpu/resctrl/internal.h |  2 +--
 arch/x86/kernel/cpu/resctrl/monitor.c  | 16 +++++++++++++-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 16 +++++++++++++-
 4 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index e590dd3..cf29681 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -347,36 +347,6 @@ static void cat_wrmsr(struct msr_param *m)
 		wrmsrl(hw_res->msr_base + i, hw_dom->ctrl_val[i]);
 }
 
-struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu, struct rdt_resource *r)
-{
-	struct rdt_ctrl_domain *d;
-
-	lockdep_assert_cpus_held();
-
-	list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
-		/* Find the domain that contains this CPU */
-		if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask))
-			return d;
-	}
-
-	return NULL;
-}
-
-struct rdt_mon_domain *get_mon_domain_from_cpu(int cpu, struct rdt_resource *r)
-{
-	struct rdt_mon_domain *d;
-
-	lockdep_assert_cpus_held();
-
-	list_for_each_entry(d, &r->mon_domains, hdr.list) {
-		/* Find the domain that contains this CPU */
-		if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask))
-			return d;
-	}
-
-	return NULL;
-}
-
 u32 resctrl_arch_get_num_closid(struct rdt_resource *r)
 {
 	return resctrl_to_arch_res(r)->num_closid;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 0d13006..c44c5b4 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -475,8 +475,6 @@ unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r, struct rdt_ctrl_domain
 				  unsigned long cbm);
 enum rdtgrp_mode rdtgroup_mode_by_closid(int closid);
 int rdtgroup_tasks_assigned(struct rdtgroup *r);
-struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu, struct rdt_resource *r);
-struct rdt_mon_domain *get_mon_domain_from_cpu(int cpu, struct rdt_resource *r);
 int closids_supported(void);
 void closid_free(int closid);
 int alloc_rmid(u32 closid);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 83f9012..a93ed7d 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -718,6 +718,22 @@ void mon_event_count(void *info)
 		rr->err = 0;
 }
 
+static struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu,
+							struct rdt_resource *r)
+{
+	struct rdt_ctrl_domain *d;
+
+	lockdep_assert_cpus_held();
+
+	list_for_each_entry(d, &r->ctrl_domains, hdr.list) {
+		/* Find the domain that contains this CPU */
+		if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask))
+			return d;
+	}
+
+	return NULL;
+}
+
 /*
  * Feedback loop for MBA software controller (mba_sc)
  *
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 5fc60c9..c6274d4 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4257,6 +4257,22 @@ static void clear_childcpus(struct rdtgroup *r, unsigned int cpu)
 	}
 }
 
+static struct rdt_mon_domain *get_mon_domain_from_cpu(int cpu,
+						      struct rdt_resource *r)
+{
+	struct rdt_mon_domain *d;
+
+	lockdep_assert_cpus_held();
+
+	list_for_each_entry(d, &r->mon_domains, hdr.list) {
+		/* Find the domain that contains this CPU */
+		if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask))
+			return d;
+	}
+
+	return NULL;
+}
+
 void resctrl_offline_cpu(unsigned int cpu)
 {
 	struct rdt_resource *l3 = resctrl_arch_get_resource(RDT_RESOURCE_L3);

[tip: x86/cache] x86/resctrl: Move get_config_index() to a header

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     f62b4e45e0b467cba75ae816338b996c6dc4dafa
Gitweb:        https://git.kernel.org/tip/f62b4e45e0b467cba75ae816338b996c6dc4dafa
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:14 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:54 +01:00

x86/resctrl: Move get_config_index() to a header

get_config_index() is used by the architecture specific code to map
a CLOSID+type pair to an index in the configuration arrays.

MPAM needs to do this too to preserve the ABI to user-space, there is no
reason to do it differently.

Move the helper to a header file to allow all architectures that either
use or emulate CDP to use the same pattern of CLOSID values. Moving
this to a header file means it must be marked inline, which matches
the existing compiler choice for this static function.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-30-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 19 +++----------------
 include/linux/resctrl.h                   | 15 +++++++++++++++
 2 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 1ecc932..0a0ac5f 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -287,25 +287,12 @@ next:
 	return -EINVAL;
 }
 
-static u32 get_config_index(u32 closid, enum resctrl_conf_type type)
-{
-	switch (type) {
-	default:
-	case CDP_NONE:
-		return closid;
-	case CDP_CODE:
-		return closid * 2 + 1;
-	case CDP_DATA:
-		return closid * 2;
-	}
-}
-
 int resctrl_arch_update_one(struct rdt_resource *r, struct rdt_ctrl_domain *d,
 			    u32 closid, enum resctrl_conf_type t, u32 cfg_val)
 {
 	struct rdt_hw_ctrl_domain *hw_dom = resctrl_to_arch_ctrl_dom(d);
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
-	u32 idx = get_config_index(closid, t);
+	u32 idx = resctrl_get_config_index(closid, t);
 	struct msr_param msr_param;
 
 	if (!cpumask_test_cpu(smp_processor_id(), &d->hdr.cpu_mask))
@@ -342,7 +329,7 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid)
 			if (!cfg->have_new_ctrl)
 				continue;
 
-			idx = get_config_index(closid, t);
+			idx = resctrl_get_config_index(closid, t);
 			if (cfg->new_ctrl == hw_dom->ctrl_val[idx])
 				continue;
 			hw_dom->ctrl_val[idx] = cfg->new_ctrl;
@@ -462,7 +449,7 @@ u32 resctrl_arch_get_config(struct rdt_resource *r, struct rdt_ctrl_domain *d,
 			    u32 closid, enum resctrl_conf_type type)
 {
 	struct rdt_hw_ctrl_domain *hw_dom = resctrl_to_arch_ctrl_dom(d);
-	u32 idx = get_config_index(closid, type);
+	u32 idx = resctrl_get_config_index(closid, type);
 
 	return hw_dom->ctrl_val[idx];
 }
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 226cc5c..880351c 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -384,6 +384,21 @@ void resctrl_arch_mon_event_config_write(void *config_info);
  */
 void resctrl_arch_mon_event_config_read(void *config_info);
 
+/* For use by arch code to remap resctrl's smaller CDP CLOSID range */
+static inline u32 resctrl_get_config_index(u32 closid,
+					   enum resctrl_conf_type type)
+{
+	switch (type) {
+	default:
+	case CDP_NONE:
+		return closid;
+	case CDP_CODE:
+		return closid * 2 + 1;
+	case CDP_DATA:
+		return closid * 2;
+	}
+}
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.

[tip: x86/cache] x86/resctrl: Handle throttle_mode for SMBA resources

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     6c2282d42cb37f081587412f77340138b1df265e
Gitweb:        https://git.kernel.org/tip/6c2282d42cb37f081587412f77340138b1df265e
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:13 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:46 +01:00

x86/resctrl: Handle throttle_mode for SMBA resources

Now that the visibility of throttle_mode is being managed by resctrl, it
should consider resources other than MBA that may have a throttle_mode.  SMBA
is one such resource.

Extend thread_throttle_mode_init() to check SMBA for a throttle_mode.

Adding support for multiple resources means it is possible for a platform with
both MBA and SMBA, but an undefined throttle_mode on one of them to make the
file visible.

Add the 'undefined' case to rdt_thread_throttle_mode_show().

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-29-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 33 ++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 58feba3..5fc60c9 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1188,10 +1188,19 @@ static int rdt_thread_throttle_mode_show(struct kernfs_open_file *of,
 	struct resctrl_schema *s = of->kn->parent->priv;
 	struct rdt_resource *r = s->res;
 
-	if (r->membw.throttle_mode == THREAD_THROTTLE_PER_THREAD)
+	switch (r->membw.throttle_mode) {
+	case THREAD_THROTTLE_PER_THREAD:
 		seq_puts(seq, "per-thread\n");
-	else
+		return 0;
+	case THREAD_THROTTLE_MAX:
 		seq_puts(seq, "max\n");
+		return 0;
+	case THREAD_THROTTLE_UNDEFINED:
+		seq_puts(seq, "undefined\n");
+		return 0;
+	}
+
+	WARN_ON_ONCE(1);
 
 	return 0;
 }
@@ -2066,12 +2075,24 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
 
 static void thread_throttle_mode_init(void)
 {
-	struct rdt_resource *r_mba;
+	enum membw_throttle_mode throttle_mode = THREAD_THROTTLE_UNDEFINED;
+	struct rdt_resource *r_mba, *r_smba;
 
 	r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
-	if (r_mba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
-		resctrl_file_fflags_init("thread_throttle_mode",
-					 RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
+	if (r_mba->alloc_capable &&
+	    r_mba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
+		throttle_mode = r_mba->membw.throttle_mode;
+
+	r_smba = resctrl_arch_get_resource(RDT_RESOURCE_SMBA);
+	if (r_smba->alloc_capable &&
+	    r_smba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
+		throttle_mode = r_smba->membw.throttle_mode;
+
+	if (throttle_mode == THREAD_THROTTLE_UNDEFINED)
+		return;
+
+	resctrl_file_fflags_init("thread_throttle_mode",
+				 RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
 }
 
 void resctrl_file_fflags_init(const char *config, unsigned long fflags)

[tip: x86/cache] x86/resctrl: Move RFTYPE flags to be managed by resctrl

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     373af4ecfdc922657be081b3feebbd0af8e7fa65
Gitweb:        https://git.kernel.org/tip/373af4ecfdc922657be081b3feebbd0af8e7fa65
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:12 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:37 +01:00

x86/resctrl: Move RFTYPE flags to be managed by resctrl

resctrl_file_fflags_init() is called from the architecture specific code to
make the 'thread_throttle_mode' file visible. The architecture specific code
has already set the membw.throttle_mode in the rdt_resource.

This forces the RFTYPE flags used by resctrl to be exposed to the architecture
specific code.

This doesn't need to be specific to the architecture, the throttle_mode can be
used by resctrl to determine if the 'thread_throttle_mode' file should be
visible. This allows the RFTYPE flags to be private to resctrl.

Add thread_throttle_mode_init(), and use it to call resctrl_file_fflags_init()
from resctrl_init(). This avoids publishing an extra function between the
architecture and filesystem code.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-28-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c     |  3 ---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 12 ++++++++++++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index b9b74f5..e590dd3 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -227,9 +227,6 @@ static __init bool __get_mem_config_intel(struct rdt_resource *r)
 	else
 		r->membw.throttle_mode = THREAD_THROTTLE_MAX;
 
-	resctrl_file_fflags_init("thread_throttle_mode",
-				 RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
-
 	r->alloc_capable = true;
 
 	return true;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index e592715..58feba3 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2064,6 +2064,16 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
 	return NULL;
 }
 
+static void thread_throttle_mode_init(void)
+{
+	struct rdt_resource *r_mba;
+
+	r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
+	if (r_mba->membw.throttle_mode != THREAD_THROTTLE_UNDEFINED)
+		resctrl_file_fflags_init("thread_throttle_mode",
+					 RFTYPE_CTRL_INFO | RFTYPE_RES_MB);
+}
+
 void resctrl_file_fflags_init(const char *config, unsigned long fflags)
 {
 	struct rftype *rft;
@@ -4277,6 +4287,8 @@ int __init resctrl_init(void)
 
 	rdtgroup_setup_default();
 
+	thread_throttle_mode_init();
+
 	ret = resctrl_mon_resource_init();
 	if (ret)
 		return ret;

[tip: x86/cache] x86/resctrl: Make resctrl_arch_pseudo_lock_fn() take a plr

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     4cf9acfc8f1a322576f0666b882d631cfdf714bf
Gitweb:        https://git.kernel.org/tip/4cf9acfc8f1a322576f0666b882d631cfdf714bf
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:11 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:33 +01:00

x86/resctrl: Make resctrl_arch_pseudo_lock_fn() take a plr

resctrl_arch_pseudo_lock_fn() has architecture specific behaviour,
and takes a struct rdtgroup as an argument.

After the filesystem code moves to /fs/, the definition of struct
rdtgroup will not be available to the architecture code.

The only reason resctrl_arch_pseudo_lock_fn() wants the rdtgroup is
for the CLOSID. Embed that in the pseudo_lock_region as a closid,
and move the definition of struct pseudo_lock_region to resctrl.h.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-27-james.morse@arm.com
---
 arch/x86/include/asm/resctrl.h            |  2 +-
 arch/x86/kernel/cpu/resctrl/internal.h    | 37 +---------------------
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 12 +++----
 include/linux/resctrl.h                   | 39 ++++++++++++++++++++++-
 4 files changed, 46 insertions(+), 44 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 86407db..011bf67 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -204,7 +204,7 @@ static inline void resctrl_arch_mon_ctx_free(struct rdt_resource *r, int evtid,
 					     void *ctx) { };
 
 u64 resctrl_arch_get_prefetch_disable_bits(void);
-int resctrl_arch_pseudo_lock_fn(void *_rdtgrp);
+int resctrl_arch_pseudo_lock_fn(void *_plr);
 int resctrl_arch_measure_cycles_lat_fn(void *_plr);
 int resctrl_arch_measure_l2_residency(void *_plr);
 int resctrl_arch_measure_l3_residency(void *_plr);
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 8d35bb4..0d13006 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -209,43 +209,6 @@ struct mongroup {
 };
 
 /**
- * struct pseudo_lock_region - pseudo-lock region information
- * @s:			Resctrl schema for the resource to which this
- *			pseudo-locked region belongs
- * @d:			RDT domain to which this pseudo-locked region
- *			belongs
- * @cbm:		bitmask of the pseudo-locked region
- * @lock_thread_wq:	waitqueue used to wait on the pseudo-locking thread
- *			completion
- * @thread_done:	variable used by waitqueue to test if pseudo-locking
- *			thread completed
- * @cpu:		core associated with the cache on which the setup code
- *			will be run
- * @line_size:		size of the cache lines
- * @size:		size of pseudo-locked region in bytes
- * @kmem:		the kernel memory associated with pseudo-locked region
- * @minor:		minor number of character device associated with this
- *			region
- * @debugfs_dir:	pointer to this region's directory in the debugfs
- *			filesystem
- * @pm_reqs:		Power management QoS requests related to this region
- */
-struct pseudo_lock_region {
-	struct resctrl_schema	*s;
-	struct rdt_ctrl_domain	*d;
-	u32			cbm;
-	wait_queue_head_t	lock_thread_wq;
-	int			thread_done;
-	int			cpu;
-	unsigned int		line_size;
-	unsigned int		size;
-	void			*kmem;
-	unsigned int		minor;
-	struct dentry		*debugfs_dir;
-	struct list_head	pm_reqs;
-};
-
-/**
  * struct rdtgroup - store rdtgroup's data in resctrl file system.
  * @kn:				kernfs node
  * @rdtgroup_list:		linked list for all rdtgroups
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index 90044a0..01fa789 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -414,7 +414,7 @@ static void pseudo_lock_free(struct rdtgroup *rdtgrp)
 
 /**
  * resctrl_arch_pseudo_lock_fn - Load kernel memory into cache
- * @_rdtgrp: resource group to which pseudo-lock region belongs
+ * @_plr: the pseudo-lock region descriptor
  *
  * This is the core pseudo-locking flow.
  *
@@ -431,10 +431,9 @@ static void pseudo_lock_free(struct rdtgroup *rdtgrp)
  *
  * Return: 0. Waiter on waitqueue will be woken on completion.
  */
-int resctrl_arch_pseudo_lock_fn(void *_rdtgrp)
+int resctrl_arch_pseudo_lock_fn(void *_plr)
 {
-	struct rdtgroup *rdtgrp = _rdtgrp;
-	struct pseudo_lock_region *plr = rdtgrp->plr;
+	struct pseudo_lock_region *plr = _plr;
 	u32 rmid_p, closid_p;
 	unsigned long i;
 	u64 saved_msr;
@@ -494,7 +493,8 @@ int resctrl_arch_pseudo_lock_fn(void *_rdtgrp)
 	 * pseudo-locked followed by reading of kernel memory to load it
 	 * into the cache.
 	 */
-	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, rdtgrp->closid);
+	__wrmsr(MSR_IA32_PQR_ASSOC, rmid_p, plr->closid);
+
 	/*
 	 * Cache was flushed earlier. Now access kernel memory to read it
 	 * into cache region associated with just activated plr->closid.
@@ -1312,7 +1312,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 
 	plr->thread_done = 0;
 
-	thread = kthread_run_on_cpu(resctrl_arch_pseudo_lock_fn, rdtgrp,
+	thread = kthread_run_on_cpu(resctrl_arch_pseudo_lock_fn, plr,
 				    plr->cpu, "pseudo_lock/%u");
 	if (IS_ERR(thread)) {
 		ret = PTR_ERR(thread);
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 914df24..226cc5c 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -58,6 +58,45 @@ enum resctrl_conf_type {
 
 #define CDP_NUM_TYPES	(CDP_DATA + 1)
 
+/*
+ * struct pseudo_lock_region - pseudo-lock region information
+ * @s:			Resctrl schema for the resource to which this
+ *			pseudo-locked region belongs
+ * @closid:		The closid that this pseudo-locked region uses
+ * @d:			RDT domain to which this pseudo-locked region
+ *			belongs
+ * @cbm:		bitmask of the pseudo-locked region
+ * @lock_thread_wq:	waitqueue used to wait on the pseudo-locking thread
+ *			completion
+ * @thread_done:	variable used by waitqueue to test if pseudo-locking
+ *			thread completed
+ * @cpu:		core associated with the cache on which the setup code
+ *			will be run
+ * @line_size:		size of the cache lines
+ * @size:		size of pseudo-locked region in bytes
+ * @kmem:		the kernel memory associated with pseudo-locked region
+ * @minor:		minor number of character device associated with this
+ *			region
+ * @debugfs_dir:	pointer to this region's directory in the debugfs
+ *			filesystem
+ * @pm_reqs:		Power management QoS requests related to this region
+ */
+struct pseudo_lock_region {
+	struct resctrl_schema	*s;
+	u32			closid;
+	struct rdt_ctrl_domain	*d;
+	u32			cbm;
+	wait_queue_head_t	lock_thread_wq;
+	int			thread_done;
+	int			cpu;
+	unsigned int		line_size;
+	unsigned int		size;
+	void			*kmem;
+	unsigned int		minor;
+	struct dentry		*debugfs_dir;
+	struct list_head	pm_reqs;
+};
+
 /**
  * struct resctrl_staged_config - parsed configuration to be applied
  * @new_ctrl:		new ctrl value to be loaded

[tip: x86/cache] x86/resctrl: Make prefetch_disable_bits belong to the arch code

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     4d20f38ab6d922dd6b8a33795b6e72516d733eb2
Gitweb:        https://git.kernel.org/tip/4d20f38ab6d922dd6b8a33795b6e72516d733eb2
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:10 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:30 +01:00

x86/resctrl: Make prefetch_disable_bits belong to the arch code

prefetch_disable_bits is set by rdtgroup_locksetup_enter() from a value
provided by the architecture, but is largely read by other architecture
helpers.

Make resctrl_arch_get_prefetch_disable_bits() set prefetch_disable_bits so
that it can be isolated to arch-code from where the other arch-code helpers
can use its cached value.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-26-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index 1f42c11..90044a0 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -84,6 +84,8 @@ static const struct class pseudo_lock_class = {
  */
 u64 resctrl_arch_get_prefetch_disable_bits(void)
 {
+	prefetch_disable_bits = 0;
+
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
 	    boot_cpu_data.x86 != 6)
 		return 0;
@@ -99,7 +101,8 @@ u64 resctrl_arch_get_prefetch_disable_bits(void)
 		 * 3    DCU IP Prefetcher Disable (R/W)
 		 * 63:4 Reserved
 		 */
-		return 0xF;
+		prefetch_disable_bits = 0xF;
+		break;
 	case INTEL_ATOM_GOLDMONT:
 	case INTEL_ATOM_GOLDMONT_PLUS:
 		/*
@@ -110,10 +113,11 @@ u64 resctrl_arch_get_prefetch_disable_bits(void)
 		 * 2     DCU Hardware Prefetcher Disable (R/W)
 		 * 63:3  Reserved
 		 */
-		return 0x5;
+		prefetch_disable_bits = 0x5;
+		break;
 	}
 
-	return 0;
+	return prefetch_disable_bits;
 }
 
 /**
@@ -713,8 +717,7 @@ int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp)
 	 * Not knowing the bits to disable prefetching implies that this
 	 * platform does not support Cache Pseudo-Locking.
 	 */
-	prefetch_disable_bits = resctrl_arch_get_prefetch_disable_bits();
-	if (prefetch_disable_bits == 0) {
+	if (resctrl_arch_get_prefetch_disable_bits() == 0) {
 		rdt_last_cmd_puts("Pseudo-locking not supported\n");
 		return -EINVAL;
 	}

[tip: x86/cache] x86/resctrl: Allow an architecture to disable pseudo lock

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     7028840552a220ac5efe51a4b554195cd954a912
Gitweb:        https://git.kernel.org/tip/7028840552a220ac5efe51a4b554195cd954a912
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:09 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:25 +01:00

x86/resctrl: Allow an architecture to disable pseudo lock

Pseudo-lock relies on knowledge of the micro-architecture to disable
prefetchers etc.

On arm64 these controls are typically secure only, meaning Linux can't access
them. Arm's cache-lockdown feature works in a very different way. Resctrl's
pseudo-lock isn't going to be used on arm64 platforms.

Add a Kconfig symbol that can be selected by the architecture. This enables or
disables building of the pseudo_lock.c file, and replaces the functions with
stubs. An additional IS_ENABLED() check is needed in rdtgroup_mode_write() so
that attempting to enable pseudo-lock reports an "Unknown or unsupported mode"
to user-space via the last_cmd_status file.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-25-james.morse@arm.com
---
 arch/x86/Kconfig                       |  7 ++++-
 arch/x86/kernel/cpu/resctrl/Makefile   |  5 +--
 arch/x86/kernel/cpu/resctrl/internal.h | 49 ++++++++++++++++++++-----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  3 +-
 4 files changed, 53 insertions(+), 11 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 0e27ebd..3cb3acd 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -505,6 +505,7 @@ config X86_CPU_RESCTRL
 	depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
 	select KERNFS
 	select PROC_CPU_RESCTRL		if PROC_FS
+	select RESCTRL_FS_PSEUDO_LOCK
 	help
 	  Enable x86 CPU resource control support.
 
@@ -521,6 +522,12 @@ config X86_CPU_RESCTRL
 
 	  Say N if unsure.
 
+config RESCTRL_FS_PSEUDO_LOCK
+	bool
+	help
+	  Software mechanism to pin data in a cache portion using
+	  micro-architecture specific knowledge.
+
 config X86_FRED
 	bool "Flexible Return and Event Delivery"
 	depends on X86_64
diff --git a/arch/x86/kernel/cpu/resctrl/Makefile b/arch/x86/kernel/cpu/resctrl/Makefile
index 4a06c37..0c13b0b 100644
--- a/arch/x86/kernel/cpu/resctrl/Makefile
+++ b/arch/x86/kernel/cpu/resctrl/Makefile
@@ -1,4 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_X86_CPU_RESCTRL)	+= core.o rdtgroup.o monitor.o
-obj-$(CONFIG_X86_CPU_RESCTRL)	+= ctrlmondata.o pseudo_lock.o
+obj-$(CONFIG_X86_CPU_RESCTRL)		+= core.o rdtgroup.o monitor.o
+obj-$(CONFIG_X86_CPU_RESCTRL)		+= ctrlmondata.o
+obj-$(CONFIG_RESCTRL_FS_PSEUDO_LOCK)	+= pseudo_lock.o
 CFLAGS_pseudo_lock.o = -I$(src)
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 725f223..8d35bb4 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -512,14 +512,6 @@ unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r, struct rdt_ctrl_domain
 				  unsigned long cbm);
 enum rdtgrp_mode rdtgroup_mode_by_closid(int closid);
 int rdtgroup_tasks_assigned(struct rdtgroup *r);
-int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp);
-int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp);
-bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_ctrl_domain *d, unsigned long cbm);
-bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d);
-int rdt_pseudo_lock_init(void);
-void rdt_pseudo_lock_release(void);
-int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp);
-void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp);
 struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu, struct rdt_resource *r);
 struct rdt_mon_domain *get_mon_domain_from_cpu(int cpu, struct rdt_resource *r);
 int closids_supported(void);
@@ -551,4 +543,45 @@ void resctrl_file_fflags_init(const char *config, unsigned long fflags);
 void rdt_staged_configs_clear(void);
 bool closid_allocated(unsigned int closid);
 int resctrl_find_cleanest_closid(void);
+
+#ifdef CONFIG_RESCTRL_FS_PSEUDO_LOCK
+int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp);
+int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp);
+bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_ctrl_domain *d, unsigned long cbm);
+bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d);
+int rdt_pseudo_lock_init(void);
+void rdt_pseudo_lock_release(void);
+int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp);
+void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp);
+#else
+static inline int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int rdtgroup_locksetup_exit(struct rdtgroup *rdtgrp)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline bool rdtgroup_cbm_overlaps_pseudo_locked(struct rdt_ctrl_domain *d, unsigned long cbm)
+{
+	return false;
+}
+
+static inline bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d)
+{
+	return false;
+}
+
+static inline int rdt_pseudo_lock_init(void) { return 0; }
+static inline void rdt_pseudo_lock_release(void) { }
+static inline int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline void rdtgroup_pseudo_lock_remove(struct rdtgroup *rdtgrp) { }
+#endif /* CONFIG_RESCTRL_FS_PSEUDO_LOCK */
+
 #endif /* _ASM_X86_RESCTRL_INTERNAL_H */
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index a388ef6..e592715 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1453,7 +1453,8 @@ static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of,
 				goto out;
 		}
 		rdtgrp->mode = RDT_MODE_EXCLUSIVE;
-	} else if (!strcmp(buf, "pseudo-locksetup")) {
+	} else if (IS_ENABLED(CONFIG_RESCTRL_FS_PSEUDO_LOCK) &&
+		   !strcmp(buf, "pseudo-locksetup")) {
 		ret = rdtgroup_locksetup_enter(rdtgrp);
 		if (ret)
 			goto out;

[tip: x86/cache] x86/resctrl: Add resctrl_arch_ prefix to pseudo lock functions

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     7d0ec14c64a107a548616deace93a1913e5d68ed
Gitweb:        https://git.kernel.org/tip/7d0ec14c64a107a548616deace93a1913e5d68ed
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:08 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:22 +01:00

x86/resctrl: Add resctrl_arch_ prefix to pseudo lock functions

resctrl's pseudo lock has some copy-to-cache and measurement functions that
are micro-architecture specific.

For example, pseudo_lock_fn() is not at all portable.

Label these 'resctrl_arch_' so they stay under /arch/x86.  To expose these
functions to the filesystem code they need an entry in a header file, and
can't be marked static.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-24-james.morse@arm.com
---
 arch/x86/include/asm/resctrl.h            |  5 +++-
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 36 +++++++++++-----------
 2 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 6d4c7ea..86407db 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -203,6 +203,11 @@ static inline void *resctrl_arch_mon_ctx_alloc(struct rdt_resource *r, int evtid
 static inline void resctrl_arch_mon_ctx_free(struct rdt_resource *r, int evtid,
 					     void *ctx) { };
 
+u64 resctrl_arch_get_prefetch_disable_bits(void);
+int resctrl_arch_pseudo_lock_fn(void *_rdtgrp);
+int resctrl_arch_measure_cycles_lat_fn(void *_plr);
+int resctrl_arch_measure_l2_residency(void *_plr);
+int resctrl_arch_measure_l3_residency(void *_plr);
 void resctrl_cpu_detect(struct cpuinfo_x86 *c);
 
 #else
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index 42cc162..1f42c11 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -61,7 +61,8 @@ static const struct class pseudo_lock_class = {
 };
 
 /**
- * get_prefetch_disable_bits - prefetch disable bits of supported platforms
+ * resctrl_arch_get_prefetch_disable_bits - prefetch disable bits of supported
+ *                                          platforms
  * @void: It takes no parameters.
  *
  * Capture the list of platforms that have been validated to support
@@ -75,13 +76,13 @@ static const struct class pseudo_lock_class = {
  * in the SDM.
  *
  * When adding a platform here also add support for its cache events to
- * measure_cycles_perf_fn()
+ * resctrl_arch_measure_l*_residency()
  *
  * Return:
  * If platform is supported, the bits to disable hardware prefetchers, 0
  * if platform is not supported.
  */
-static u64 get_prefetch_disable_bits(void)
+u64 resctrl_arch_get_prefetch_disable_bits(void)
 {
 	if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL ||
 	    boot_cpu_data.x86 != 6)
@@ -408,7 +409,7 @@ static void pseudo_lock_free(struct rdtgroup *rdtgrp)
 }
 
 /**
- * pseudo_lock_fn - Load kernel memory into cache
+ * resctrl_arch_pseudo_lock_fn - Load kernel memory into cache
  * @_rdtgrp: resource group to which pseudo-lock region belongs
  *
  * This is the core pseudo-locking flow.
@@ -426,7 +427,7 @@ static void pseudo_lock_free(struct rdtgroup *rdtgrp)
  *
  * Return: 0. Waiter on waitqueue will be woken on completion.
  */
-static int pseudo_lock_fn(void *_rdtgrp)
+int resctrl_arch_pseudo_lock_fn(void *_rdtgrp)
 {
 	struct rdtgroup *rdtgrp = _rdtgrp;
 	struct pseudo_lock_region *plr = rdtgrp->plr;
@@ -712,7 +713,7 @@ int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp)
 	 * Not knowing the bits to disable prefetching implies that this
 	 * platform does not support Cache Pseudo-Locking.
 	 */
-	prefetch_disable_bits = get_prefetch_disable_bits();
+	prefetch_disable_bits = resctrl_arch_get_prefetch_disable_bits();
 	if (prefetch_disable_bits == 0) {
 		rdt_last_cmd_puts("Pseudo-locking not supported\n");
 		return -EINVAL;
@@ -872,7 +873,8 @@ bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d)
 }
 
 /**
- * measure_cycles_lat_fn - Measure cycle latency to read pseudo-locked memory
+ * resctrl_arch_measure_cycles_lat_fn - Measure cycle latency to read
+ *                                      pseudo-locked memory
  * @_plr: pseudo-lock region to measure
  *
  * There is no deterministic way to test if a memory region is cached. One
@@ -885,7 +887,7 @@ bool rdtgroup_pseudo_locked_in_hierarchy(struct rdt_ctrl_domain *d)
  *
  * Return: 0. Waiter on waitqueue will be woken on completion.
  */
-static int measure_cycles_lat_fn(void *_plr)
+int resctrl_arch_measure_cycles_lat_fn(void *_plr)
 {
 	struct pseudo_lock_region *plr = _plr;
 	u32 saved_low, saved_high;
@@ -1069,7 +1071,7 @@ out:
 	return 0;
 }
 
-static int measure_l2_residency(void *_plr)
+int resctrl_arch_measure_l2_residency(void *_plr)
 {
 	struct pseudo_lock_region *plr = _plr;
 	struct residency_counts counts = {0};
@@ -1107,7 +1109,7 @@ out:
 	return 0;
 }
 
-static int measure_l3_residency(void *_plr)
+int resctrl_arch_measure_l3_residency(void *_plr)
 {
 	struct pseudo_lock_region *plr = _plr;
 	struct residency_counts counts = {0};
@@ -1205,14 +1207,14 @@ static int pseudo_lock_measure_cycles(struct rdtgroup *rdtgrp, int sel)
 	plr->cpu = cpu;
 
 	if (sel == 1)
-		thread = kthread_run_on_cpu(measure_cycles_lat_fn, plr,
-					    cpu, "pseudo_lock_measure/%u");
+		thread = kthread_run_on_cpu(resctrl_arch_measure_cycles_lat_fn,
+					    plr, cpu, "pseudo_lock_measure/%u");
 	else if (sel == 2)
-		thread = kthread_run_on_cpu(measure_l2_residency, plr,
-					    cpu, "pseudo_lock_measure/%u");
+		thread = kthread_run_on_cpu(resctrl_arch_measure_l2_residency,
+					    plr, cpu, "pseudo_lock_measure/%u");
 	else if (sel == 3)
-		thread = kthread_run_on_cpu(measure_l3_residency, plr,
-					    cpu, "pseudo_lock_measure/%u");
+		thread = kthread_run_on_cpu(resctrl_arch_measure_l3_residency,
+					    plr, cpu, "pseudo_lock_measure/%u");
 	else
 		goto out;
 
@@ -1307,7 +1309,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 
 	plr->thread_done = 0;
 
-	thread = kthread_run_on_cpu(pseudo_lock_fn, rdtgrp,
+	thread = kthread_run_on_cpu(resctrl_arch_pseudo_lock_fn, rdtgrp,
 				    plr->cpu, "pseudo_lock/%u");
 	if (IS_ERR(thread)) {
 		ret = PTR_ERR(thread);

[tip: x86/cache] x86/resctrl: Move mbm_cfg_mask to struct rdt_resource

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     c32a7d7777800b61a5c9272cc94fe21aa919b305
Gitweb:        https://git.kernel.org/tip/c32a7d7777800b61a5c9272cc94fe21aa919b305
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:07 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:24:09 +01:00

x86/resctrl: Move mbm_cfg_mask to struct rdt_resource

The mbm_cfg_mask field lists the bits that user-space can set when configuring
an event. This value is output via the last_cmd_status file.

Once the filesystem parts of resctrl are moved to live in /fs/, the struct
rdt_hw_resource is inaccessible to the filesystem code. Because this value is
output to user-space, it has to be accessible to the filesystem code.

Move it to struct rdt_resource.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-23-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/internal.h | 3 ---
 arch/x86/kernel/cpu/resctrl/monitor.c  | 2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 5 ++---
 include/linux/resctrl.h                | 3 +++
 4 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 4a5996d..725f223 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -417,8 +417,6 @@ struct msr_param {
  * @msr_update:		Function pointer to update QOS MSRs
  * @mon_scale:		cqm counter * mon_scale = occupancy in bytes
  * @mbm_width:		Monitor width, to detect and correct for overflow.
- * @mbm_cfg_mask:	Bandwidth sources that can be tracked when Bandwidth
- *			Monitoring Event Configuration (BMEC) is supported.
  * @cdp_enabled:	CDP state of this resource
  *
  * Members of this structure are either private to the architecture
@@ -432,7 +430,6 @@ struct rdt_hw_resource {
 	void			(*msr_update)(struct msr_param *m);
 	unsigned int		mon_scale;
 	unsigned int		mbm_width;
-	unsigned int		mbm_cfg_mask;
 	bool			cdp_enabled;
 };
 
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 306b06b..83f9012 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1260,7 +1260,7 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 
 		/* Detect list of bandwidth sources that can be tracked */
 		cpuid_count(0x80000020, 3, &eax, &ebx, &ecx, &edx);
-		hw_res->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
+		r->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
 	}
 
 	r->mon_capable = true;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index e7d1d8b..a388ef6 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1731,7 +1731,6 @@ static void mbm_config_write_domain(struct rdt_resource *r,
 
 static int mon_config_write(struct rdt_resource *r, char *tok, u32 evtid)
 {
-	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
 	char *dom_str = NULL, *id_str;
 	unsigned long dom_id, val;
 	struct rdt_mon_domain *d;
@@ -1758,9 +1757,9 @@ next:
 	}
 
 	/* Value from user cannot be more than the supported set of events */
-	if ((val & hw_res->mbm_cfg_mask) != val) {
+	if ((val & r->mbm_cfg_mask) != val) {
 		rdt_last_cmd_printf("Invalid event configuration: max valid mask is 0x%02x\n",
-				    hw_res->mbm_cfg_mask);
+				    r->mbm_cfg_mask);
 		return -EINVAL;
 	}
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 90b6563..914df24 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -217,6 +217,8 @@ enum resctrl_schema_fmt {
  * @name:		Name to use in "schemata" file.
  * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
+ * @mbm_cfg_mask:	Bandwidth sources that can be tracked when bandwidth
+ *			monitoring events can be configured.
  * @cdp_capable:	Is the CDP feature available on this resource
  */
 struct rdt_resource {
@@ -233,6 +235,7 @@ struct rdt_resource {
 	char			*name;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
+	unsigned int		mbm_cfg_mask;
 	bool			cdp_capable;
 };
 

[tip: x86/cache] x86/resctrl: Move mba_mbps_default_event init to filesystem code

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     37bae1756734b065f5e5cddc54ad121ff0c8db51
Gitweb:        https://git.kernel.org/tip/37bae1756734b065f5e5cddc54ad121ff0c8db51
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:06 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:52 +01:00

x86/resctrl: Move mba_mbps_default_event init to filesystem code

mba_mbps_default_event is initialised based on whether mbm_local or mbm_total
is supported. In the case of both, it is initialised to mbm_local.
mba_mbps_default_event is initialised in core.c's get_rdt_mon_resources(),
while all the readers are in rdtgroup.c.

After this code is split into architecture-specific and filesystem code,
get_rdt_mon_resources() remains part of the architecture code, which would
mean mba_mbps_default_event has to be exposed by the filesystem code.

Move the initialisation to the filesystem's resctrl_mon_resource_init().

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-22-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c    | 5 -----
 arch/x86/kernel/cpu/resctrl/monitor.c | 5 +++++
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 6f0d1bb..b9b74f5 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -923,11 +923,6 @@ static __init bool get_rdt_mon_resources(void)
 	if (!rdt_mon_features)
 		return false;
 
-	if (resctrl_arch_is_mbm_local_enabled())
-		mba_mbps_default_event = QOS_L3_MBM_LOCAL_EVENT_ID;
-	else if (resctrl_arch_is_mbm_total_enabled())
-		mba_mbps_default_event = QOS_L3_MBM_TOTAL_EVENT_ID;
-
 	return !rdt_get_mon_l3_config(r);
 }
 
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 27d9831..306b06b 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1213,6 +1213,11 @@ int __init resctrl_mon_resource_init(void)
 					 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
 	}
 
+	if (resctrl_arch_is_mbm_local_enabled())
+		mba_mbps_default_event = QOS_L3_MBM_LOCAL_EVENT_ID;
+	else if (resctrl_arch_is_mbm_total_enabled())
+		mba_mbps_default_event = QOS_L3_MBM_TOTAL_EVENT_ID;
+
 	return 0;
 }
 

[tip: x86/cache] x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     650680d651aaf409f097ad904c3fea6c4b3a0884
Gitweb:        https://git.kernel.org/tip/650680d651aaf409f097ad904c3fea6c4b3a0884
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:05 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:49 +01:00

x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers

mon_event_config_{read,write}() are called via IPI and access model specific
registers to do their work.

To support another architecture, this needs abstracting.

Rename mon_event_config_{read,write}() to have a "resctrl_arch_" prefix, and
move their struct mon_config_info parameter into <linux/resctrl.h>.  This
allows another architecture to supply an implementation of these.

As struct mon_config_info is now exposed globally, give it a 'resctrl_'
prefix. MPAM systems need access to the domain to do this work, add the
resource and domain to struct resctrl_mon_config_info.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-21-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 46 ++++++++++++-------------
 include/linux/resctrl.h                | 31 +++++++++++++++++-
 2 files changed, 54 insertions(+), 23 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index eb32fbc..e7d1d8b 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1580,11 +1580,6 @@ out:
 	return ret;
 }
 
-struct mon_config_info {
-	u32 evtid;
-	u32 mon_config;
-};
-
 #define INVALID_CONFIG_INDEX   UINT_MAX
 
 /**
@@ -1609,31 +1604,32 @@ static inline unsigned int mon_event_config_index_get(u32 evtid)
 	}
 }
 
-static void mon_event_config_read(void *info)
+void resctrl_arch_mon_event_config_read(void *_config_info)
 {
-	struct mon_config_info *mon_info = info;
+	struct resctrl_mon_config_info *config_info = _config_info;
 	unsigned int index;
 	u64 msrval;
 
-	index = mon_event_config_index_get(mon_info->evtid);
+	index = mon_event_config_index_get(config_info->evtid);
 	if (index == INVALID_CONFIG_INDEX) {
-		pr_warn_once("Invalid event id %d\n", mon_info->evtid);
+		pr_warn_once("Invalid event id %d\n", config_info->evtid);
 		return;
 	}
 	rdmsrl(MSR_IA32_EVT_CFG_BASE + index, msrval);
 
 	/* Report only the valid event configuration bits */
-	mon_info->mon_config = msrval & MAX_EVT_CONFIG_BITS;
+	config_info->mon_config = msrval & MAX_EVT_CONFIG_BITS;
 }
 
-static void mondata_config_read(struct rdt_mon_domain *d, struct mon_config_info *mon_info)
+static void mondata_config_read(struct resctrl_mon_config_info *mon_info)
 {
-	smp_call_function_any(&d->hdr.cpu_mask, mon_event_config_read, mon_info, 1);
+	smp_call_function_any(&mon_info->d->hdr.cpu_mask,
+			      resctrl_arch_mon_event_config_read, mon_info, 1);
 }
 
 static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid)
 {
-	struct mon_config_info mon_info;
+	struct resctrl_mon_config_info mon_info;
 	struct rdt_mon_domain *dom;
 	bool sep = false;
 
@@ -1644,9 +1640,11 @@ static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid
 		if (sep)
 			seq_puts(s, ";");
 
-		memset(&mon_info, 0, sizeof(struct mon_config_info));
+		memset(&mon_info, 0, sizeof(struct resctrl_mon_config_info));
+		mon_info.r = r;
+		mon_info.d = dom;
 		mon_info.evtid = evtid;
-		mondata_config_read(dom, &mon_info);
+		mondata_config_read(&mon_info);
 
 		seq_printf(s, "%d=0x%02x", dom->hdr.id, mon_info.mon_config);
 		sep = true;
@@ -1679,30 +1677,32 @@ static int mbm_local_bytes_config_show(struct kernfs_open_file *of,
 	return 0;
 }
 
-static void mon_event_config_write(void *info)
+void resctrl_arch_mon_event_config_write(void *_config_info)
 {
-	struct mon_config_info *mon_info = info;
+	struct resctrl_mon_config_info *config_info = _config_info;
 	unsigned int index;
 
-	index = mon_event_config_index_get(mon_info->evtid);
+	index = mon_event_config_index_get(config_info->evtid);
 	if (index == INVALID_CONFIG_INDEX) {
-		pr_warn_once("Invalid event id %d\n", mon_info->evtid);
+		pr_warn_once("Invalid event id %d\n", config_info->evtid);
 		return;
 	}
-	wrmsr(MSR_IA32_EVT_CFG_BASE + index, mon_info->mon_config, 0);
+	wrmsr(MSR_IA32_EVT_CFG_BASE + index, config_info->mon_config, 0);
 }
 
 static void mbm_config_write_domain(struct rdt_resource *r,
 				    struct rdt_mon_domain *d, u32 evtid, u32 val)
 {
-	struct mon_config_info mon_info = {0};
+	struct resctrl_mon_config_info mon_info = {0};
 
 	/*
 	 * Read the current config value first. If both are the same then
 	 * no need to write it again.
 	 */
+	mon_info.r = r;
+	mon_info.d = d;
 	mon_info.evtid = evtid;
-	mondata_config_read(d, &mon_info);
+	mondata_config_read(&mon_info);
 	if (mon_info.mon_config == val)
 		return;
 
@@ -1714,7 +1714,7 @@ static void mbm_config_write_domain(struct rdt_resource *r,
 	 * are scoped at the domain level. Writing any of these MSRs
 	 * on one CPU is observed by all the CPUs in the domain.
 	 */
-	smp_call_function_any(&d->hdr.cpu_mask, mon_event_config_write,
+	smp_call_function_any(&d->hdr.cpu_mask, resctrl_arch_mon_event_config_write,
 			      &mon_info, 1);
 
 	/*
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index cc76f30..90b6563 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -270,6 +270,13 @@ struct resctrl_cpu_defaults {
 	u32 rmid;
 };
 
+struct resctrl_mon_config_info {
+	struct rdt_resource	*r;
+	struct rdt_mon_domain	*d;
+	u32			evtid;
+	u32			mon_config;
+};
+
 /**
  * resctrl_arch_sync_cpu_closid_rmid() - Refresh this CPU's CLOSID and RMID.
  *					 Call via IPI.
@@ -311,6 +318,30 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
 __init bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt);
 
+/**
+ * resctrl_arch_mon_event_config_write() - Write the config for an event.
+ * @config_info: struct resctrl_mon_config_info describing the resource, domain
+ *		 and event.
+ *
+ * Reads resource, domain and eventid from @config_info and writes the
+ * event config_info->mon_config into hardware.
+ *
+ * Called via IPI to reach a CPU that is a member of the specified domain.
+ */
+void resctrl_arch_mon_event_config_write(void *config_info);
+
+/**
+ * resctrl_arch_mon_event_config_read() - Read the config for an event.
+ * @config_info: struct resctrl_mon_config_info describing the resource, domain
+ *		 and event.
+ *
+ * Reads resource, domain and eventid from @config_info and reads the
+ * hardware config value into config_info->mon_config.
+ *
+ * Called via IPI to reach a CPU that is a member of the specified domain.
+ */
+void resctrl_arch_mon_event_config_read(void *config_info);
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.

[tip: x86/cache] x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     d81826f87a80a86cc5963ff3c44f05700ded3fc9
Gitweb:        https://git.kernel.org/tip/d81826f87a80a86cc5963ff3c44f05700ded3fc9
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:04 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:45 +01:00

x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC

When BMEC is supported the resctrl event can be configured in a number of
ways. This depends on architecture support. rdt_get_mon_l3_config() modifies
the struct mon_evt and calls resctrl_file_fflags_init() to create the files
that allow the configuration.

Splitting this into separate architecture and filesystem parts would require
the struct mon_evt and resctrl_file_fflags_init() to be exposed.

Instead, add resctrl_arch_is_evt_configurable(), and use this from
resctrl_mon_resource_init() to initialise struct mon_evt and call
resctrl_file_fflags_init().

resctrl_arch_is_evt_configurable() calls rdt_cpu_has() so it doesn't obviously
benefit from being inlined. Putting it in core.c will allow rdt_cpu_has() to
eventually become static.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-20-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c    | 15 +++++++++++++++
 arch/x86/kernel/cpu/resctrl/monitor.c | 22 +++++++++++-----------
 include/linux/resctrl.h               |  2 ++
 3 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index eba210d..6f0d1bb 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -830,6 +830,21 @@ bool __init rdt_cpu_has(int flag)
 	return ret;
 }
 
+__init bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt)
+{
+	if (!rdt_cpu_has(X86_FEATURE_BMEC))
+		return false;
+
+	switch (evt) {
+	case QOS_L3_MBM_TOTAL_EVENT_ID:
+		return rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL);
+	case QOS_L3_MBM_LOCAL_EVENT_ID:
+		return rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL);
+	default:
+		return false;
+	}
+}
+
 static __init bool get_mem_config(void)
 {
 	struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_MBA];
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index d883ed5..27d9831 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1202,6 +1202,17 @@ int __init resctrl_mon_resource_init(void)
 
 	l3_mon_evt_init(r);
 
+	if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_TOTAL_EVENT_ID)) {
+		mbm_total_event.configurable = true;
+		resctrl_file_fflags_init("mbm_total_bytes_config",
+					 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
+	}
+	if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_LOCAL_EVENT_ID)) {
+		mbm_local_event.configurable = true;
+		resctrl_file_fflags_init("mbm_local_bytes_config",
+					 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
+	}
+
 	return 0;
 }
 
@@ -1245,17 +1256,6 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 		/* Detect list of bandwidth sources that can be tracked */
 		cpuid_count(0x80000020, 3, &eax, &ebx, &ecx, &edx);
 		hw_res->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
-
-		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL)) {
-			mbm_total_event.configurable = true;
-			resctrl_file_fflags_init("mbm_total_bytes_config",
-						 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
-		}
-		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {
-			mbm_local_event.configurable = true;
-			resctrl_file_fflags_init("mbm_local_bytes_config",
-						 RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
-		}
 	}
 
 	r->mon_capable = true;
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index a392480..cc76f30 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -309,6 +309,8 @@ u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
 u32 resctrl_arch_system_num_rmid_idx(void);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
+__init bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt);
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.

[tip: x86/cache] x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkers

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     88464bff035ecb28f8bf52dd9728fdc1aca228f9
Gitweb:        https://git.kernel.org/tip/88464bff035ecb28f8bf52dd9728fdc1aca228f9
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:02 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:30 +01:00

x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkers

The for_each_*_rdt_resource() helpers walk the architecture's array of
structures, using the resctrl visible part as an iterator. These became
over-complex when the structures were split into a filesystem and
architecture-specific struct. This approach avoided the need to touch every
call site, and was done before there was a helper to retrieve a resource by
rid.

Once the filesystem parts of resctrl are moved to /fs/, both the arch's
resource array, and the definition of those structures is no longer
accessible. To support resctrl, each architecture would have to provide
equally complex macros.

Rewrite the macro to make use of resctrl_arch_get_resource(), and move these
to include/linux/resctrl.h so existing x86 arch code continues to use them.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-18-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/internal.h | 29 +-------------------------
 include/linux/resctrl.h                | 18 ++++++++++++++++-
 2 files changed, 18 insertions(+), 29 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 70fbb90..82dbc16 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -475,14 +475,6 @@ extern struct rdtgroup rdtgroup_default;
 extern struct dentry *debugfs_resctrl;
 extern enum resctrl_event_id mba_mbps_default_event;
 
-static inline struct rdt_resource *resctrl_inc(struct rdt_resource *res)
-{
-	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(res);
-
-	hw_res++;
-	return &hw_res->r_resctrl;
-}
-
 static inline bool resctrl_arch_get_cdp_enabled(enum resctrl_res_level l)
 {
 	return rdt_resources_all[l].cdp_enabled;
@@ -492,27 +484,6 @@ int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable);
 
 void arch_mon_domain_online(struct rdt_resource *r, struct rdt_mon_domain *d);
 
-/*
- * To return the common struct rdt_resource, which is contained in struct
- * rdt_hw_resource, walk the resctrl member of struct rdt_hw_resource.
- */
-#define for_each_rdt_resource(r)					      \
-	for (r = &rdt_resources_all[0].r_resctrl;			      \
-	     r <= &rdt_resources_all[RDT_NUM_RESOURCES - 1].r_resctrl;	      \
-	     r = resctrl_inc(r))
-
-#define for_each_capable_rdt_resource(r)				      \
-	for_each_rdt_resource(r)					      \
-		if (r->alloc_capable || r->mon_capable)
-
-#define for_each_alloc_capable_rdt_resource(r)				      \
-	for_each_rdt_resource(r)					      \
-		if (r->alloc_capable)
-
-#define for_each_mon_capable_rdt_resource(r)				      \
-	for_each_rdt_resource(r)					      \
-		if (r->mon_capable)
-
 /* CPUID.(EAX=10H, ECX=ResID=1).EAX */
 union cpuid_0x10_1_eax {
 	struct {
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 487b965..a392480 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -26,6 +26,24 @@ int proc_resctrl_show(struct seq_file *m,
 /* max value for struct rdt_domain's mbps_val */
 #define MBA_MAX_MBPS   U32_MAX
 
+/* Walk all possible resources, with variants for only controls or monitors. */
+#define for_each_rdt_resource(_r)						\
+	for ((_r) = resctrl_arch_get_resource(0);				\
+	     (_r) && (_r)->rid < RDT_NUM_RESOURCES;				\
+	     (_r) = resctrl_arch_get_resource((_r)->rid + 1))
+
+#define for_each_capable_rdt_resource(r)				      \
+	for_each_rdt_resource((r))					      \
+		if ((r)->alloc_capable || (r)->mon_capable)
+
+#define for_each_alloc_capable_rdt_resource(r)				      \
+	for_each_rdt_resource((r))					      \
+		if ((r)->alloc_capable)
+
+#define for_each_mon_capable_rdt_resource(r)				      \
+	for_each_rdt_resource((r))					      \
+		if ((r)->mon_capable)
+
 /**
  * enum resctrl_conf_type - The type of configuration.
  * @CDP_NONE:	No prioritisation, both code and data are controlled or monitored.

[tip: x86/cache] x86/resctrl: Move the is_mbm_*_enabled() helpers to asm/resctrl.h

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     d012b66a16618509242a51f5f6c9b19868ba5159
Gitweb:        https://git.kernel.org/tip/d012b66a16618509242a51f5f6c9b19868ba5159
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:03 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:33 +01:00

x86/resctrl: Move the is_mbm_*_enabled() helpers to asm/resctrl.h

The architecture specific parts of resctrl provide helpers like
is_mbm_total_enabled() and is_mbm_local_enabled() to hide accesses to the
rdt_mon_features bitmap.

Exposing a group of helpers between the architecture and filesystem code is
preferable to a single unsigned-long like rdt_mon_features. Helpers can be more
readable and have a well defined behaviour, while allowing architectures to hide
more complex behaviour.

Once the filesystem parts of resctrl are moved, these existing helpers can no
longer live in internal.h. Move them to include/linux/resctrl.h Once these are
exposed to the wider kernel, they should have a 'resctrl_arch_' prefix, to fit
the rest of the arch<->fs interface.

Move and rename the helpers that touch rdt_mon_features directly. is_mbm_event()
and is_mbm_enabled() are only called from rdtgroup.c, so can be moved into that
file.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-19-james.morse@arm.com
---
 arch/x86/include/asm/resctrl.h            | 16 +++++++++-
 arch/x86/kernel/cpu/resctrl/core.c        |  8 ++--
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  4 +-
 arch/x86/kernel/cpu/resctrl/internal.h    | 27 +---------------
 arch/x86/kernel/cpu/resctrl/monitor.c     | 16 ++++-----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 40 ++++++++++++++--------
 6 files changed, 56 insertions(+), 55 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 52f2326..6d4c7ea 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -42,6 +42,7 @@ DECLARE_PER_CPU(struct resctrl_pqr_state, pqr_state);
 
 extern bool rdt_alloc_capable;
 extern bool rdt_mon_capable;
+extern unsigned int rdt_mon_features;
 
 DECLARE_STATIC_KEY_FALSE(rdt_enable_key);
 DECLARE_STATIC_KEY_FALSE(rdt_alloc_enable_key);
@@ -81,6 +82,21 @@ static inline void resctrl_arch_disable_mon(void)
 	static_branch_dec_cpuslocked(&rdt_enable_key);
 }
 
+static inline bool resctrl_arch_is_llc_occupancy_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID));
+}
+
+static inline bool resctrl_arch_is_mbm_total_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID));
+}
+
+static inline bool resctrl_arch_is_mbm_local_enabled(void)
+{
+	return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID));
+}
+
 /*
  * __resctrl_sched_in() - Writes the task's CLOSid/RMID to IA32_PQR_MSR
  *
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index a1577bd..eba210d 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -453,13 +453,13 @@ static int arch_domain_mbm_alloc(u32 num_rmid, struct rdt_hw_mon_domain *hw_dom)
 {
 	size_t tsize;
 
-	if (is_mbm_total_enabled()) {
+	if (resctrl_arch_is_mbm_total_enabled()) {
 		tsize = sizeof(*hw_dom->arch_mbm_total);
 		hw_dom->arch_mbm_total = kcalloc(num_rmid, tsize, GFP_KERNEL);
 		if (!hw_dom->arch_mbm_total)
 			return -ENOMEM;
 	}
-	if (is_mbm_local_enabled()) {
+	if (resctrl_arch_is_mbm_local_enabled()) {
 		tsize = sizeof(*hw_dom->arch_mbm_local);
 		hw_dom->arch_mbm_local = kcalloc(num_rmid, tsize, GFP_KERNEL);
 		if (!hw_dom->arch_mbm_local) {
@@ -908,9 +908,9 @@ static __init bool get_rdt_mon_resources(void)
 	if (!rdt_mon_features)
 		return false;
 
-	if (is_mbm_local_enabled())
+	if (resctrl_arch_is_mbm_local_enabled())
 		mba_mbps_default_event = QOS_L3_MBM_LOCAL_EVENT_ID;
-	else if (is_mbm_total_enabled())
+	else if (resctrl_arch_is_mbm_total_enabled())
 		mba_mbps_default_event = QOS_L3_MBM_TOTAL_EVENT_ID;
 
 	return !rdt_get_mon_l3_config(r);
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 763317e..1ecc932 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -559,12 +559,12 @@ ssize_t rdtgroup_mba_mbps_event_write(struct kernfs_open_file *of,
 	rdt_last_cmd_clear();
 
 	if (!strcmp(buf, "mbm_local_bytes")) {
-		if (is_mbm_local_enabled())
+		if (resctrl_arch_is_mbm_local_enabled())
 			rdtgrp->mba_mbps_event = QOS_L3_MBM_LOCAL_EVENT_ID;
 		else
 			ret = -EINVAL;
 	} else if (!strcmp(buf, "mbm_total_bytes")) {
-		if (is_mbm_total_enabled())
+		if (resctrl_arch_is_mbm_total_enabled())
 			rdtgrp->mba_mbps_event = QOS_L3_MBM_TOTAL_EVENT_ID;
 		else
 			ret = -EINVAL;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 82dbc16..4a5996d 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -156,7 +156,6 @@ struct rmid_read {
 	void			*arch_mon_ctx;
 };
 
-extern unsigned int rdt_mon_features;
 extern struct list_head resctrl_schema_all;
 extern bool resctrl_mounted;
 
@@ -406,32 +405,6 @@ struct msr_param {
 	u32			high;
 };
 
-static inline bool is_llc_occupancy_enabled(void)
-{
-	return (rdt_mon_features & (1 << QOS_L3_OCCUP_EVENT_ID));
-}
-
-static inline bool is_mbm_total_enabled(void)
-{
-	return (rdt_mon_features & (1 << QOS_L3_MBM_TOTAL_EVENT_ID));
-}
-
-static inline bool is_mbm_local_enabled(void)
-{
-	return (rdt_mon_features & (1 << QOS_L3_MBM_LOCAL_EVENT_ID));
-}
-
-static inline bool is_mbm_enabled(void)
-{
-	return (is_mbm_total_enabled() || is_mbm_local_enabled());
-}
-
-static inline bool is_mbm_event(int e)
-{
-	return (e >= QOS_L3_MBM_TOTAL_EVENT_ID &&
-		e <= QOS_L3_MBM_LOCAL_EVENT_ID);
-}
-
 /**
  * struct rdt_hw_resource - arch private attributes of a resctrl resource
  * @r_resctrl:		Attributes of the resource used directly by resctrl.
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 1730ba8..d883ed5 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -295,11 +295,11 @@ void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_mon_domain *
 {
 	struct rdt_hw_mon_domain *hw_dom = resctrl_to_arch_mon_dom(d);
 
-	if (is_mbm_total_enabled())
+	if (resctrl_arch_is_mbm_total_enabled())
 		memset(hw_dom->arch_mbm_total, 0,
 		       sizeof(*hw_dom->arch_mbm_total) * r->num_rmid);
 
-	if (is_mbm_local_enabled())
+	if (resctrl_arch_is_mbm_local_enabled())
 		memset(hw_dom->arch_mbm_local, 0,
 		       sizeof(*hw_dom->arch_mbm_local) * r->num_rmid);
 }
@@ -569,7 +569,7 @@ void free_rmid(u32 closid, u32 rmid)
 
 	entry = __rmid_entry(idx);
 
-	if (is_llc_occupancy_enabled())
+	if (resctrl_arch_is_llc_occupancy_enabled())
 		add_rmid_to_limbo(entry);
 	else
 		list_add_tail(&entry->list, &rmid_free_lru);
@@ -852,10 +852,10 @@ static void mbm_update(struct rdt_resource *r, struct rdt_mon_domain *d,
 	 * This is protected from concurrent reads from user as both
 	 * the user and overflow handler hold the global mutex.
 	 */
-	if (is_mbm_total_enabled())
+	if (resctrl_arch_is_mbm_total_enabled())
 		mbm_update_one_event(r, d, closid, rmid, QOS_L3_MBM_TOTAL_EVENT_ID);
 
-	if (is_mbm_local_enabled())
+	if (resctrl_arch_is_mbm_local_enabled())
 		mbm_update_one_event(r, d, closid, rmid, QOS_L3_MBM_LOCAL_EVENT_ID);
 }
 
@@ -1085,11 +1085,11 @@ static void l3_mon_evt_init(struct rdt_resource *r)
 {
 	INIT_LIST_HEAD(&r->evt_list);
 
-	if (is_llc_occupancy_enabled())
+	if (resctrl_arch_is_llc_occupancy_enabled())
 		list_add_tail(&llc_occupancy_event.list, &r->evt_list);
-	if (is_mbm_total_enabled())
+	if (resctrl_arch_is_mbm_total_enabled())
 		list_add_tail(&mbm_total_event.list, &r->evt_list);
-	if (is_mbm_local_enabled())
+	if (resctrl_arch_is_mbm_local_enabled())
 		list_add_tail(&mbm_local_event.list, &r->evt_list);
 }
 
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index badac3f..eb32fbc 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -117,6 +117,18 @@ void rdt_staged_configs_clear(void)
 	}
 }
 
+static bool resctrl_is_mbm_enabled(void)
+{
+	return (resctrl_arch_is_mbm_total_enabled() ||
+		resctrl_arch_is_mbm_local_enabled());
+}
+
+static bool resctrl_is_mbm_event(int e)
+{
+	return (e >= QOS_L3_MBM_TOTAL_EVENT_ID &&
+		e <= QOS_L3_MBM_LOCAL_EVENT_ID);
+}
+
 /*
  * Trivial allocator for CLOSIDs. Since h/w only supports a small number,
  * we can keep a bitmap of free CLOSIDs in a single integer.
@@ -164,7 +176,7 @@ static int closid_alloc(void)
 	lockdep_assert_held(&rdtgroup_mutex);
 
 	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID) &&
-	    is_llc_occupancy_enabled()) {
+	    resctrl_arch_is_llc_occupancy_enabled()) {
 		cleanest_closid = resctrl_find_cleanest_closid();
 		if (cleanest_closid < 0)
 			return cleanest_closid;
@@ -2378,7 +2390,7 @@ static bool supports_mba_mbps(void)
 	struct rdt_resource *rmbm = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 
-	return (is_mbm_enabled() &&
+	return (resctrl_is_mbm_enabled() &&
 		r->alloc_capable && is_mba_linear() &&
 		r->ctrl_scope == rmbm->mon_scope);
 }
@@ -2756,7 +2768,7 @@ static int rdt_get_tree(struct fs_context *fc)
 	if (resctrl_arch_alloc_capable() || resctrl_arch_mon_capable())
 		resctrl_mounted = true;
 
-	if (is_mbm_enabled()) {
+	if (resctrl_is_mbm_enabled()) {
 		r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 		list_for_each_entry(dom, &r->mon_domains, hdr.list)
 			mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL,
@@ -3125,7 +3137,7 @@ static int mon_add_all_files(struct kernfs_node *kn, struct rdt_mon_domain *d,
 		if (ret)
 			return ret;
 
-		if (!do_sum && is_mbm_event(mevt->evtid))
+		if (!do_sum && resctrl_is_mbm_event(mevt->evtid))
 			mon_event_read(&rr, r, d, prgrp, &d->hdr.cpu_mask, mevt->evtid, true);
 	}
 
@@ -4082,9 +4094,9 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d
 	if (resctrl_mounted && resctrl_arch_mon_capable())
 		rmdir_mondata_subdir_allrdtgrp(r, d);
 
-	if (is_mbm_enabled())
+	if (resctrl_is_mbm_enabled())
 		cancel_delayed_work(&d->mbm_over);
-	if (is_llc_occupancy_enabled() && has_busy_rmid(d)) {
+	if (resctrl_arch_is_llc_occupancy_enabled() && has_busy_rmid(d)) {
 		/*
 		 * When a package is going down, forcefully
 		 * decrement rmid->ebusy. There is no way to know
@@ -4120,12 +4132,12 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_mon_domain 
 	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
 	size_t tsize;
 
-	if (is_llc_occupancy_enabled()) {
+	if (resctrl_arch_is_llc_occupancy_enabled()) {
 		d->rmid_busy_llc = bitmap_zalloc(idx_limit, GFP_KERNEL);
 		if (!d->rmid_busy_llc)
 			return -ENOMEM;
 	}
-	if (is_mbm_total_enabled()) {
+	if (resctrl_arch_is_mbm_total_enabled()) {
 		tsize = sizeof(*d->mbm_total);
 		d->mbm_total = kcalloc(idx_limit, tsize, GFP_KERNEL);
 		if (!d->mbm_total) {
@@ -4133,7 +4145,7 @@ static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_mon_domain 
 			return -ENOMEM;
 		}
 	}
-	if (is_mbm_local_enabled()) {
+	if (resctrl_arch_is_mbm_local_enabled()) {
 		tsize = sizeof(*d->mbm_local);
 		d->mbm_local = kcalloc(idx_limit, tsize, GFP_KERNEL);
 		if (!d->mbm_local) {
@@ -4172,13 +4184,13 @@ int resctrl_online_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d)
 	if (err)
 		goto out_unlock;
 
-	if (is_mbm_enabled()) {
+	if (resctrl_is_mbm_enabled()) {
 		INIT_DELAYED_WORK(&d->mbm_over, mbm_handle_overflow);
 		mbm_setup_overflow_handler(d, MBM_OVERFLOW_INTERVAL,
 					   RESCTRL_PICK_ANY_CPU);
 	}
 
-	if (is_llc_occupancy_enabled())
+	if (resctrl_arch_is_llc_occupancy_enabled())
 		INIT_DELAYED_WORK(&d->cqm_limbo, cqm_handle_limbo);
 
 	/*
@@ -4233,12 +4245,12 @@ void resctrl_offline_cpu(unsigned int cpu)
 
 	d = get_mon_domain_from_cpu(cpu, l3);
 	if (d) {
-		if (is_mbm_enabled() && cpu == d->mbm_work_cpu) {
+		if (resctrl_is_mbm_enabled() && cpu == d->mbm_work_cpu) {
 			cancel_delayed_work(&d->mbm_over);
 			mbm_setup_overflow_handler(d, 0, cpu);
 		}
-		if (is_llc_occupancy_enabled() && cpu == d->cqm_work_cpu &&
-		    has_busy_rmid(d)) {
+		if (resctrl_arch_is_llc_occupancy_enabled() &&
+		    cpu == d->cqm_work_cpu && has_busy_rmid(d)) {
 			cancel_delayed_work(&d->cqm_limbo);
 			cqm_setup_limbo_handler(d, 0, cpu);
 		}

[tip: x86/cache] x86/resctrl: Move monitor init work to a resctrl init call

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     4b6bdbf27fcee16944911155293771b880344ef0
Gitweb:        https://git.kernel.org/tip/4b6bdbf27fcee16944911155293771b880344ef0
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:01 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:21 +01:00

x86/resctrl: Move monitor init work to a resctrl init call

rdt_get_mon_l3_config() is called from the arch's resctrl_arch_late_init(),
and initialises both architecture specific fields, such as hw_res->mon_scale
and resctrl filesystem fields by calling dom_data_init().

To separate the filesystem and architecture parts of resctrl, this function
needs splitting up.

Add resctrl_mon_resource_init() to do the filesystem specific work, and call
it from resctrl_init(). This runs later, but is still before the filesystem is
mounted and the rmid_ptrs[] array can be used.

  [ bp: Massage commit message. ]

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-17-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/internal.h |  3 +-
 arch/x86/kernel/cpu/resctrl/monitor.c  | 40 +++++++++++++++++++------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 22 +++++++++++++-
 3 files changed, 54 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 73005ca..70fbb90 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -586,13 +586,14 @@ void closid_free(int closid);
 int alloc_rmid(u32 closid);
 void free_rmid(u32 closid, u32 rmid);
 int rdt_get_mon_l3_config(struct rdt_resource *r);
-void __exit resctrl_mon_resource_exit(void);
+void resctrl_mon_resource_exit(void);
 bool __init rdt_cpu_has(int flag);
 void mon_event_count(void *info);
 int rdtgroup_mondata_show(struct seq_file *m, void *arg);
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
 		    struct rdt_mon_domain *d, struct rdtgroup *rdtgrp,
 		    cpumask_t *cpumask, int evtid, int first);
+int __init resctrl_mon_resource_init(void);
 void mbm_setup_overflow_handler(struct rdt_mon_domain *dom,
 				unsigned long delay_ms,
 				int exclude_cpu);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 15e8c01..1730ba8 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1040,7 +1040,7 @@ out_unlock:
 	return err;
 }
 
-static void __exit dom_data_exit(struct rdt_resource *r)
+static void dom_data_exit(struct rdt_resource *r)
 {
 	mutex_lock(&rdtgroup_mutex);
 
@@ -1176,12 +1176,40 @@ static __init int snc_get_config(void)
 	return ret;
 }
 
+/**
+ * resctrl_mon_resource_init() - Initialise global monitoring structures.
+ *
+ * Allocate and initialise global monitor resources that do not belong to a
+ * specific domain. i.e. the rmid_ptrs[] used for the limbo and free lists.
+ * Called once during boot after the struct rdt_resource's have been configured
+ * but before the filesystem is mounted.
+ * Resctrl's cpuhp callbacks may be called before this point to bring a domain
+ * online.
+ *
+ * Returns 0 for success, or -ENOMEM.
+ */
+int __init resctrl_mon_resource_init(void)
+{
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
+	int ret;
+
+	if (!r->mon_capable)
+		return 0;
+
+	ret = dom_data_init(r);
+	if (ret)
+		return ret;
+
+	l3_mon_evt_init(r);
+
+	return 0;
+}
+
 int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 {
 	unsigned int mbm_offset = boot_cpu_data.x86_cache_mbm_width_offset;
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
 	unsigned int threshold;
-	int ret;
 
 	snc_nodes_per_l3_cache = snc_get_config();
 
@@ -1211,10 +1239,6 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 	 */
 	resctrl_rmid_realloc_threshold = resctrl_arch_round_mon_val(threshold);
 
-	ret = dom_data_init(r);
-	if (ret)
-		return ret;
-
 	if (rdt_cpu_has(X86_FEATURE_BMEC)) {
 		u32 eax, ebx, ecx, edx;
 
@@ -1234,14 +1258,12 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 		}
 	}
 
-	l3_mon_evt_init(r);
-
 	r->mon_capable = true;
 
 	return 0;
 }
 
-void __exit resctrl_mon_resource_exit(void)
+void resctrl_mon_resource_exit(void)
 {
 	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 42c48e7..badac3f 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4102,6 +4102,19 @@ void resctrl_offline_mon_domain(struct rdt_resource *r, struct rdt_mon_domain *d
 	mutex_unlock(&rdtgroup_mutex);
 }
 
+/**
+ * domain_setup_mon_state() -  Initialise domain monitoring structures.
+ * @r:	The resource for the newly online domain.
+ * @d:	The newly online domain.
+ *
+ * Allocate monitor resources that belong to this domain.
+ * Called when the first CPU of a domain comes online, regardless of whether
+ * the filesystem is mounted.
+ * During boot this may be called before global allocations have been made by
+ * resctrl_mon_resource_init().
+ *
+ * Returns 0 for success, or -ENOMEM.
+ */
 static int domain_setup_mon_state(struct rdt_resource *r, struct rdt_mon_domain *d)
 {
 	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
@@ -4252,10 +4265,16 @@ int __init resctrl_init(void)
 
 	rdtgroup_setup_default();
 
-	ret = sysfs_create_mount_point(fs_kobj, "resctrl");
+	ret = resctrl_mon_resource_init();
 	if (ret)
 		return ret;
 
+	ret = sysfs_create_mount_point(fs_kobj, "resctrl");
+	if (ret) {
+		resctrl_mon_resource_exit();
+		return ret;
+	}
+
 	ret = register_filesystem(&rdt_fs_type);
 	if (ret)
 		goto cleanup_mountpoint;
@@ -4287,6 +4306,7 @@ int __init resctrl_init(void)
 
 cleanup_mountpoint:
 	sysfs_remove_mount_point(fs_kobj, "resctrl");
+	resctrl_mon_resource_exit();
 
 	return ret;
 }

[tip: x86/cache] x86/resctrl: Move monitor exit work to a resctrl exit call

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     011842727fa449f834c17b69d1273d88eb6e3309
Gitweb:        https://git.kernel.org/tip/011842727fa449f834c17b69d1273d88eb6e3309
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:37:00 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:13 +01:00

x86/resctrl: Move monitor exit work to a resctrl exit call

rdt_put_mon_l3_config() is called via the architecture's resctrl_arch_exit()
call, and appears to free the rmid_ptrs[] and closid_num_dirty_rmid[] arrays.
In reality this code is marked __exit, and is removed by the linker as resctrl
can't be built as a module.

To separate the filesystem and architecture parts of resctrl, this free()ing
work needs to be triggered by the filesystem, as these structures belong to
the filesystem code.

Rename rdt_put_mon_l3_config() to resctrl_mon_resource_exit() and call it from
resctrl_exit(). The kfree() is currently dependent on r->mon_capable.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-16-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c     |  5 -----
 arch/x86/kernel/cpu/resctrl/internal.h |  2 +-
 arch/x86/kernel/cpu/resctrl/monitor.c  | 12 +++++++++---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  2 ++
 4 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 850cb86..a1577bd 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -1074,14 +1074,9 @@ late_initcall(resctrl_arch_late_init);
 
 static void __exit resctrl_arch_exit(void)
 {
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
-
 	cpuhp_remove_state(rdt_online);
 
 	resctrl_exit();
-
-	if (r->mon_capable)
-		rdt_put_mon_l3_config();
 }
 
 __exitcall(resctrl_arch_exit);
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 5f3713f..73005ca 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -586,7 +586,7 @@ void closid_free(int closid);
 int alloc_rmid(u32 closid);
 void free_rmid(u32 closid, u32 rmid);
 int rdt_get_mon_l3_config(struct rdt_resource *r);
-void __exit rdt_put_mon_l3_config(void);
+void __exit resctrl_mon_resource_exit(void);
 bool __init rdt_cpu_has(int flag);
 void mon_event_count(void *info);
 int rdtgroup_mondata_show(struct seq_file *m, void *arg);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index e8388d1..15e8c01 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1040,10 +1040,13 @@ out_unlock:
 	return err;
 }
 
-static void __exit dom_data_exit(void)
+static void __exit dom_data_exit(struct rdt_resource *r)
 {
 	mutex_lock(&rdtgroup_mutex);
 
+	if (!r->mon_capable)
+		goto out_unlock;
+
 	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) {
 		kfree(closid_num_dirty_rmid);
 		closid_num_dirty_rmid = NULL;
@@ -1052,6 +1055,7 @@ static void __exit dom_data_exit(void)
 	kfree(rmid_ptrs);
 	rmid_ptrs = NULL;
 
+out_unlock:
 	mutex_unlock(&rdtgroup_mutex);
 }
 
@@ -1237,9 +1241,11 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 	return 0;
 }
 
-void __exit rdt_put_mon_l3_config(void)
+void __exit resctrl_mon_resource_exit(void)
 {
-	dom_data_exit();
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
+
+	dom_data_exit(r);
 }
 
 void __init intel_rdt_mbm_apply_quirk(void)
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 9eb57eb..42c48e7 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4296,4 +4296,6 @@ void __exit resctrl_exit(void)
 	debugfs_remove_recursive(debugfs_resctrl);
 	unregister_filesystem(&rdt_fs_type);
 	sysfs_remove_mount_point(fs_kobj, "resctrl");
+
+	resctrl_mon_resource_exit();
 }

[tip: x86/cache] x86/resctrl: Add an arch helper to reset one resource

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     9be68b144a5b539c8503f2944888f7a30e669291
Gitweb:        https://git.kernel.org/tip/9be68b144a5b539c8503f2944888f7a30e669291
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:59 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:10 +01:00

x86/resctrl: Add an arch helper to reset one resource

On umount(), resctrl resets each resource back to its default configuration.
It only ever does this for all resources in one go.

reset_all_ctrls() is architecture specific as it works with struct
rdt_hw_resource.

Make reset_all_ctrls() an arch helper that resets one resource.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-15-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  9 +++++----
 include/linux/resctrl.h                |  9 +++++++++
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index b2dad68..9eb57eb 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2867,7 +2867,7 @@ static int rdt_init_fs_context(struct fs_context *fc)
 	return 0;
 }
 
-static int reset_all_ctrls(struct rdt_resource *r)
+void resctrl_arch_reset_all_ctrls(struct rdt_resource *r)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
 	struct rdt_hw_ctrl_domain *hw_dom;
@@ -2896,7 +2896,7 @@ static int reset_all_ctrls(struct rdt_resource *r)
 		smp_call_function_any(&d->hdr.cpu_mask, rdt_ctrl_update, &msr_param, 1);
 	}
 
-	return 0;
+	return;
 }
 
 /*
@@ -3015,9 +3015,10 @@ static void rdt_kill_sb(struct super_block *sb)
 
 	rdt_disable_ctx();
 
-	/*Put everything back to default values. */
+	/* Put everything back to default values. */
 	for_each_alloc_capable_rdt_resource(r)
-		reset_all_ctrls(r);
+		resctrl_arch_reset_all_ctrls(r);
+
 	rmdir_all_sub();
 	rdt_pseudo_lock_release();
 	rdtgroup_default.mode = RDT_MODE_SHAREABLE;
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 326f7ba..487b965 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -394,6 +394,15 @@ void resctrl_arch_reset_rmid(struct rdt_resource *r, struct rdt_mon_domain *d,
  */
 void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_mon_domain *d);
 
+/**
+ * resctrl_arch_reset_all_ctrls() - Reset the control for each CLOSID to its
+ *				    default.
+ * @r:		The resctrl resource to reset.
+ *
+ * This can be called from any CPU.
+ */
+void resctrl_arch_reset_all_ctrls(struct rdt_resource *r);
+
 extern unsigned int resctrl_rmid_realloc_threshold;
 extern unsigned int resctrl_rmid_realloc_limit;
 

[tip: x86/cache] x86/resctrl: Move resctrl types to a separate header

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     f16adbaf9272ea7ed5d7bf8b261be8a9be949c31
Gitweb:        https://git.kernel.org/tip/f16adbaf9272ea7ed5d7bf8b261be8a9be949c31
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:58 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:23:00 +01:00

x86/resctrl: Move resctrl types to a separate header

When resctrl is fully factored into core and per-arch code, each arch will
need to use some resctrl common definitions in order to define its own
specializations and helpers.  Following conventional practice, it would be
desirable to put the dependent arch definitions in an <asm/resctrl.h> header
that is included by the common <linux/resctrl.h> header.  However, this can
make it awkward to avoid a circular dependency between <linux/resctrl.h> and
the arch header.

To avoid such dependencies, move the affected common types and constants into
a new header that does not need to depend on <linux/resctrl.h> or on the arch
headers.

The same logic applies to the monitor-configuration defines, move these too.

Some kind of enumeration for events is needed between the filesystem and
architecture code. Take the x86 definition as its convenient for x86.

The definition of enum resctrl_event_id is needed to allow the architecture
code to define resctrl_arch_mon_ctx_alloc() and resctrl_arch_mon_ctx_free().

The definition of enum resctrl_res_level is needed to allow the architecture
code to define resctrl_arch_set_cdp_enabled() and
resctrl_arch_get_cdp_enabled().

The bits for mbm_local_bytes_config et al are ABI, and must be the same on all
architectures. These are documented in Documentation/arch/x86/resctrl.rst

The maintainers entry for these headers was missed when resctrl.h was created.
Add a wildcard entry to match both resctrl.h and resctrl_types.h.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-14-james.morse@arm.com
---
 MAINTAINERS                            |  1 +-
 arch/x86/include/asm/resctrl.h         |  1 +-
 arch/x86/kernel/cpu/resctrl/internal.h | 24 +-----------
 include/linux/resctrl.h                | 21 +----------
 include/linux/resctrl_types.h          | 54 +++++++++++++++++++++++++-
 5 files changed, 57 insertions(+), 44 deletions(-)
 create mode 100644 include/linux/resctrl_types.h

diff --git a/MAINTAINERS b/MAINTAINERS
index ed7aa68..2d0b669 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19894,6 +19894,7 @@ S:	Supported
 F:	Documentation/arch/x86/resctrl*
 F:	arch/x86/include/asm/resctrl.h
 F:	arch/x86/kernel/cpu/resctrl/
+F:	include/linux/resctrl*.h
 F:	tools/testing/selftests/resctrl/
 
 READ-COPY UPDATE (RCU)
diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 6908cd0..52f2326 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -6,6 +6,7 @@
 
 #include <linux/jump_label.h>
 #include <linux/percpu.h>
+#include <linux/resctrl_types.h>
 #include <linux/sched.h>
 
 /*
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index da73404..5f3713f 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -32,30 +32,6 @@
  */
 #define MBM_CNTR_WIDTH_OFFSET_MAX (62 - MBM_CNTR_WIDTH_BASE)
 
-/* Reads to Local DRAM Memory */
-#define READS_TO_LOCAL_MEM		BIT(0)
-
-/* Reads to Remote DRAM Memory */
-#define READS_TO_REMOTE_MEM		BIT(1)
-
-/* Non-Temporal Writes to Local Memory */
-#define NON_TEMP_WRITE_TO_LOCAL_MEM	BIT(2)
-
-/* Non-Temporal Writes to Remote Memory */
-#define NON_TEMP_WRITE_TO_REMOTE_MEM	BIT(3)
-
-/* Reads to Local Memory the system identifies as "Slow Memory" */
-#define READS_TO_LOCAL_S_MEM		BIT(4)
-
-/* Reads to Remote Memory the system identifies as "Slow Memory" */
-#define READS_TO_REMOTE_S_MEM		BIT(5)
-
-/* Dirty Victims to All Types of Memory */
-#define DIRTY_VICTIMS_TO_ALL_MEM	BIT(6)
-
-/* Max event bits supported */
-#define MAX_EVT_CONFIG_BITS		GENMASK(6, 0)
-
 /**
  * cpumask_any_housekeeping() - Choose any CPU in @mask, preferring those that
  *			        aren't marked nohz_full
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 93d9a43..326f7ba 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -6,6 +6,7 @@
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/pid.h>
+#include <linux/resctrl_types.h>
 
 /* CLOSID, RMID value used by the default control group */
 #define RESCTRL_RESERVED_CLOSID		0
@@ -37,28 +38,8 @@ enum resctrl_conf_type {
 	CDP_DATA,
 };
 
-enum resctrl_res_level {
-	RDT_RESOURCE_L3,
-	RDT_RESOURCE_L2,
-	RDT_RESOURCE_MBA,
-	RDT_RESOURCE_SMBA,
-
-	/* Must be the last */
-	RDT_NUM_RESOURCES,
-};
-
 #define CDP_NUM_TYPES	(CDP_DATA + 1)
 
-/*
- * Event IDs, the values match those used to program IA32_QM_EVTSEL before
- * reading IA32_QM_CTR on RDT systems.
- */
-enum resctrl_event_id {
-	QOS_L3_OCCUP_EVENT_ID		= 0x01,
-	QOS_L3_MBM_TOTAL_EVENT_ID	= 0x02,
-	QOS_L3_MBM_LOCAL_EVENT_ID	= 0x03,
-};
-
 /**
  * struct resctrl_staged_config - parsed configuration to be applied
  * @new_ctrl:		new ctrl value to be loaded
diff --git a/include/linux/resctrl_types.h b/include/linux/resctrl_types.h
new file mode 100644
index 0000000..f26450b
--- /dev/null
+++ b/include/linux/resctrl_types.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2025 Arm Ltd.
+ * Based on arch/x86/kernel/cpu/resctrl/internal.h
+ */
+
+#ifndef __LINUX_RESCTRL_TYPES_H
+#define __LINUX_RESCTRL_TYPES_H
+
+/* Reads to Local DRAM Memory */
+#define READS_TO_LOCAL_MEM		BIT(0)
+
+/* Reads to Remote DRAM Memory */
+#define READS_TO_REMOTE_MEM		BIT(1)
+
+/* Non-Temporal Writes to Local Memory */
+#define NON_TEMP_WRITE_TO_LOCAL_MEM	BIT(2)
+
+/* Non-Temporal Writes to Remote Memory */
+#define NON_TEMP_WRITE_TO_REMOTE_MEM	BIT(3)
+
+/* Reads to Local Memory the system identifies as "Slow Memory" */
+#define READS_TO_LOCAL_S_MEM		BIT(4)
+
+/* Reads to Remote Memory the system identifies as "Slow Memory" */
+#define READS_TO_REMOTE_S_MEM		BIT(5)
+
+/* Dirty Victims to All Types of Memory */
+#define DIRTY_VICTIMS_TO_ALL_MEM	BIT(6)
+
+/* Max event bits supported */
+#define MAX_EVT_CONFIG_BITS		GENMASK(6, 0)
+
+enum resctrl_res_level {
+	RDT_RESOURCE_L3,
+	RDT_RESOURCE_L2,
+	RDT_RESOURCE_MBA,
+	RDT_RESOURCE_SMBA,
+
+	/* Must be the last */
+	RDT_NUM_RESOURCES,
+};
+
+/*
+ * Event IDs, the values match those used to program IA32_QM_EVTSEL before
+ * reading IA32_QM_CTR on RDT systems.
+ */
+enum resctrl_event_id {
+	QOS_L3_OCCUP_EVENT_ID		= 0x01,
+	QOS_L3_MBM_TOTAL_EVENT_ID	= 0x02,
+	QOS_L3_MBM_LOCAL_EVENT_ID	= 0x03,
+};
+
+#endif /* __LINUX_RESCTRL_TYPES_H */

[tip: x86/cache] x86/resctrl: Move rdt_find_domain() to be visible to arch and fs code

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     e3d5138cefbffa8ea1bf8aab3629268bc3381219
Gitweb:        https://git.kernel.org/tip/e3d5138cefbffa8ea1bf8aab3629268bc3381219
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:57 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:56 +01:00

x86/resctrl: Move rdt_find_domain() to be visible to arch and fs code

rdt_find_domain() finds a domain given a resource and a cache-id.  This is
used by both the architecture code and the filesystem code.

After the filesystem code moves to live in /fs/, this helper is either
duplicated by all architectures, or needs exposing by the filesystem code.

Add the declaration to the global header file. As it's now globally visible,
and has only a handful of callers, swap the 'rdt' for 'resctrl'. Move the
function to live with its caller in ctrlmondata.c as the filesystem code will
not have anything corresponding to core.c.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-13-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c        | 38 ++--------------------
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 24 +++++++++++++-
 arch/x86/kernel/cpu/resctrl/internal.h    |  2 +-
 include/linux/resctrl.h                   | 14 ++++++++-
 4 files changed, 41 insertions(+), 37 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 2129951..850cb86 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -394,36 +394,6 @@ void rdt_ctrl_update(void *arg)
 	hw_res->msr_update(m);
 }
 
-/*
- * rdt_find_domain - Search for a domain id in a resource domain list.
- *
- * Search the domain list to find the domain id. If the domain id is
- * found, return the domain. NULL otherwise.  If the domain id is not
- * found (and NULL returned) then the first domain with id bigger than
- * the input id can be returned to the caller via @pos.
- */
-struct rdt_domain_hdr *rdt_find_domain(struct list_head *h, int id,
-				       struct list_head **pos)
-{
-	struct rdt_domain_hdr *d;
-	struct list_head *l;
-
-	list_for_each(l, h) {
-		d = list_entry(l, struct rdt_domain_hdr, list);
-		/* When id is found, return its domain. */
-		if (id == d->id)
-			return d;
-		/* Stop searching when finding id's position in sorted list. */
-		if (id < d->id)
-			break;
-	}
-
-	if (pos)
-		*pos = l;
-
-	return NULL;
-}
-
 static void setup_default_ctrlval(struct rdt_resource *r, u32 *dc)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
@@ -534,7 +504,7 @@ static void domain_add_cpu_ctrl(int cpu, struct rdt_resource *r)
 		return;
 	}
 
-	hdr = rdt_find_domain(&r->ctrl_domains, id, &add_pos);
+	hdr = resctrl_find_domain(&r->ctrl_domains, id, &add_pos);
 	if (hdr) {
 		if (WARN_ON_ONCE(hdr->type != RESCTRL_CTRL_DOMAIN))
 			return;
@@ -589,7 +559,7 @@ static void domain_add_cpu_mon(int cpu, struct rdt_resource *r)
 		return;
 	}
 
-	hdr = rdt_find_domain(&r->mon_domains, id, &add_pos);
+	hdr = resctrl_find_domain(&r->mon_domains, id, &add_pos);
 	if (hdr) {
 		if (WARN_ON_ONCE(hdr->type != RESCTRL_MON_DOMAIN))
 			return;
@@ -654,7 +624,7 @@ static void domain_remove_cpu_ctrl(int cpu, struct rdt_resource *r)
 		return;
 	}
 
-	hdr = rdt_find_domain(&r->ctrl_domains, id, NULL);
+	hdr = resctrl_find_domain(&r->ctrl_domains, id, NULL);
 	if (!hdr) {
 		pr_warn("Can't find control domain for id=%d for CPU %d for resource %s\n",
 			id, cpu, r->name);
@@ -700,7 +670,7 @@ static void domain_remove_cpu_mon(int cpu, struct rdt_resource *r)
 		return;
 	}
 
-	hdr = rdt_find_domain(&r->mon_domains, id, NULL);
+	hdr = resctrl_find_domain(&r->mon_domains, id, NULL);
 	if (!hdr) {
 		pr_warn("Can't find monitor domain for id=%d for CPU %d for resource %s\n",
 			id, cpu, r->name);
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 5d87f27..763317e 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -610,6 +610,28 @@ int rdtgroup_mba_mbps_event_show(struct kernfs_open_file *of,
 	return ret;
 }
 
+struct rdt_domain_hdr *resctrl_find_domain(struct list_head *h, int id,
+					   struct list_head **pos)
+{
+	struct rdt_domain_hdr *d;
+	struct list_head *l;
+
+	list_for_each(l, h) {
+		d = list_entry(l, struct rdt_domain_hdr, list);
+		/* When id is found, return its domain. */
+		if (id == d->id)
+			return d;
+		/* Stop searching when finding id's position in sorted list. */
+		if (id < d->id)
+			break;
+	}
+
+	if (pos)
+		*pos = l;
+
+	return NULL;
+}
+
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
 		    struct rdt_mon_domain *d, struct rdtgroup *rdtgrp,
 		    cpumask_t *cpumask, int evtid, int first)
@@ -695,7 +717,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 		 * This file provides data from a single domain. Search
 		 * the resource to find the domain with "domid".
 		 */
-		hdr = rdt_find_domain(&r->mon_domains, domid, NULL);
+		hdr = resctrl_find_domain(&r->mon_domains, domid, NULL);
 		if (!hdr || WARN_ON_ONCE(hdr->type != RESCTRL_MON_DOMAIN)) {
 			ret = -ENOENT;
 			goto out;
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 8291f1b..da73404 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -581,8 +581,6 @@ void rdtgroup_kn_unlock(struct kernfs_node *kn);
 int rdtgroup_kn_mode_restrict(struct rdtgroup *r, const char *name);
 int rdtgroup_kn_mode_restore(struct rdtgroup *r, const char *name,
 			     umode_t mask);
-struct rdt_domain_hdr *rdt_find_domain(struct list_head *h, int id,
-				       struct list_head **pos);
 ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
 				char *buf, size_t nbytes, loff_t off);
 int rdtgroup_schemata_show(struct kernfs_open_file *of,
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index f1979e3..93d9a43 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -373,6 +373,20 @@ static inline void resctrl_arch_rmid_read_context_check(void)
 }
 
 /**
+ * resctrl_find_domain() - Search for a domain id in a resource domain list.
+ * @h:		The domain list to search.
+ * @id:		The domain id to search for.
+ * @pos:	A pointer to position in the list id should be inserted.
+ *
+ * Search the domain list to find the domain id. If the domain id is
+ * found, return the domain. NULL otherwise.  If the domain id is not
+ * found (and NULL returned) then the first domain with id bigger than
+ * the input id can be returned to the caller via @pos.
+ */
+struct rdt_domain_hdr *resctrl_find_domain(struct list_head *h, int id,
+					   struct list_head **pos);
+
+/**
  * resctrl_arch_reset_rmid() - Reset any private state associated with rmid
  *			       and eventid.
  * @r:		The domain's resource.

[tip: x86/cache] x86/resctrl: Expose resctrl fs's init function to the rest of the kernel

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     8079565d177f5c4eac6c2ee2ac6c404eee76d500
Gitweb:        https://git.kernel.org/tip/8079565d177f5c4eac6c2ee2ac6c404eee76d500
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:56 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:54 +01:00

x86/resctrl: Expose resctrl fs's init function to the rest of the kernel

rdtgroup_init() needs exposing to the rest of the kernel so that arch code can
call it once it lives in core code. As this is one of the few functions
exposed, rename it to have "resctrl" in the name. The same goes for the exit
call.

Rename x86's arch code init functions for RDT to have an arch prefix to make
it clear these are part of the architecture code.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-12-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c     | 12 ++++++------
 arch/x86/kernel/cpu/resctrl/internal.h |  3 ---
 arch/x86/kernel/cpu/resctrl/monitor.c  |  2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  8 ++++----
 include/linux/resctrl.h                |  3 +++
 5 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index d001ca4..2129951 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -1061,7 +1061,7 @@ void resctrl_cpu_detect(struct cpuinfo_x86 *c)
 	}
 }
 
-static int __init resctrl_late_init(void)
+static int __init resctrl_arch_late_init(void)
 {
 	struct rdt_resource *r;
 	int state, ret;
@@ -1084,7 +1084,7 @@ static int __init resctrl_late_init(void)
 	if (state < 0)
 		return state;
 
-	ret = rdtgroup_init();
+	ret = resctrl_init();
 	if (ret) {
 		cpuhp_remove_state(state);
 		return ret;
@@ -1100,18 +1100,18 @@ static int __init resctrl_late_init(void)
 	return 0;
 }
 
-late_initcall(resctrl_late_init);
+late_initcall(resctrl_arch_late_init);
 
-static void __exit resctrl_exit(void)
+static void __exit resctrl_arch_exit(void)
 {
 	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
 
 	cpuhp_remove_state(rdt_online);
 
-	rdtgroup_exit();
+	resctrl_exit();
 
 	if (r->mon_capable)
 		rdt_put_mon_l3_config();
 }
 
-__exitcall(resctrl_exit);
+__exitcall(resctrl_arch_exit);
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index f975cd6..8291f1b 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -328,9 +328,6 @@ extern struct list_head rdt_all_groups;
 
 extern int max_name_width;
 
-int __init rdtgroup_init(void);
-void __exit rdtgroup_exit(void);
-
 /**
  * struct rftype - describe each file in the resctrl file system
  * @name:	File name
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 58b5b21..e8388d1 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1027,7 +1027,7 @@ static int dom_data_init(struct rdt_resource *r)
 	/*
 	 * RESCTRL_RESERVED_CLOSID and RESCTRL_RESERVED_RMID are special and
 	 * are always allocated. These are used for the rdtgroup_default
-	 * control group, which will be setup later in rdtgroup_init().
+	 * control group, which will be setup later in resctrl_init().
 	 */
 	idx = resctrl_arch_rmid_idx_encode(RESCTRL_RESERVED_CLOSID,
 					   RESCTRL_RESERVED_RMID);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 62d9a50..b2dad68 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4235,14 +4235,14 @@ out_unlock:
 }
 
 /*
- * rdtgroup_init - rdtgroup initialization
+ * resctrl_init - resctrl filesystem initialization
  *
  * Setup resctrl file system including set up root, create mount point,
- * register rdtgroup filesystem, and initialize files under root directory.
+ * register resctrl filesystem, and initialize files under root directory.
  *
  * Return: 0 on success or -errno
  */
-int __init rdtgroup_init(void)
+int __init resctrl_init(void)
 {
 	int ret = 0;
 
@@ -4290,7 +4290,7 @@ cleanup_mountpoint:
 	return ret;
 }
 
-void __exit rdtgroup_exit(void)
+void __exit resctrl_exit(void)
 {
 	debugfs_remove_recursive(debugfs_resctrl);
 	unregister_filesystem(&rdt_fs_type);
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 31808b3..f1979e3 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -402,4 +402,7 @@ void resctrl_arch_reset_rmid_all(struct rdt_resource *r, struct rdt_mon_domain *
 extern unsigned int resctrl_rmid_realloc_threshold;
 extern unsigned int resctrl_rmid_realloc_limit;
 
+int __init resctrl_init(void);
+void __exit resctrl_exit(void);
+
 #endif /* _RESCTRL_H */

[tip: x86/cache] x86/resctrl: Remove rdtgroup from update_cpu_closid_rmid()

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     6f06aee356bfd0c817cbe83debedd240fbed0719
Gitweb:        https://git.kernel.org/tip/6f06aee356bfd0c817cbe83debedd240fbed0719
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:55 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:51 +01:00

x86/resctrl: Remove rdtgroup from update_cpu_closid_rmid()

update_cpu_closid_rmid() takes a struct rdtgroup as an argument, which it uses
to update the local CPUs default pqr values. This is a problem once the
resctrl parts move out to /fs/, as the arch code cannot poke around inside
struct rdtgroup.

Rename update_cpu_closid_rmid() as resctrl_arch_sync_cpus_defaults() to be
used as the target of an IPI, and pass the effective CLOSID and RMID in a new
struct.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-11-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 17 +++++++++++++----
 include/linux/resctrl.h                | 22 ++++++++++++++++++++++
 2 files changed, 35 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index f706e5a..62d9a50 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -355,13 +355,13 @@ static int rdtgroup_cpus_show(struct kernfs_open_file *of,
  * from update_closid_rmid() is protected against __switch_to() because
  * preemption is disabled.
  */
-static void update_cpu_closid_rmid(void *info)
+void resctrl_arch_sync_cpu_closid_rmid(void *info)
 {
-	struct rdtgroup *r = info;
+	struct resctrl_cpu_defaults *r = info;
 
 	if (r) {
 		this_cpu_write(pqr_state.default_closid, r->closid);
-		this_cpu_write(pqr_state.default_rmid, r->mon.rmid);
+		this_cpu_write(pqr_state.default_rmid, r->rmid);
 	}
 
 	/*
@@ -376,11 +376,20 @@ static void update_cpu_closid_rmid(void *info)
  * Update the PGR_ASSOC MSR on all cpus in @cpu_mask,
  *
  * Per task closids/rmids must have been set up before calling this function.
+ * @r may be NULL.
  */
 static void
 update_closid_rmid(const struct cpumask *cpu_mask, struct rdtgroup *r)
 {
-	on_each_cpu_mask(cpu_mask, update_cpu_closid_rmid, r, 1);
+	struct resctrl_cpu_defaults defaults, *p = NULL;
+
+	if (r) {
+		defaults.closid = r->closid;
+		defaults.rmid = r->mon.rmid;
+		p = &defaults;
+	}
+
+	on_each_cpu_mask(cpu_mask, resctrl_arch_sync_cpu_closid_rmid, p, 1);
 }
 
 static int cpus_mon_write(struct rdtgroup *rdtgrp, cpumask_var_t newmask,
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index d16dc96..31808b3 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -266,6 +266,28 @@ struct resctrl_schema {
 	u32				num_closid;
 };
 
+struct resctrl_cpu_defaults {
+	u32 closid;
+	u32 rmid;
+};
+
+/**
+ * resctrl_arch_sync_cpu_closid_rmid() - Refresh this CPU's CLOSID and RMID.
+ *					 Call via IPI.
+ * @info:	If non-NULL, a pointer to a struct resctrl_cpu_defaults
+ *		specifying the new CLOSID and RMID for tasks in the default
+ *		resctrl ctrl and mon group when running on this CPU.  If NULL,
+ *		this CPU is not re-assigned to a different default group.
+ *
+ * Propagates reassignment of CPUs and/or tasks to different resctrl groups
+ * when requested by the resctrl core code.
+ *
+ * This function records the per-cpu defaults specified by @info (if any),
+ * and then reconfigures the CPU's hardware CLOSID and RMID for subsequent
+ * execution based on @current, in the same way as during a task switch.
+ */
+void resctrl_arch_sync_cpu_closid_rmid(void *info);
+
 /**
  * resctrl_get_default_ctrl() - Return the default control value for this
  *                              resource.

[tip: x86/cache] x86/resctrl: Add helper for setting CPU default properties

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     aebd5354dd191860033f8599048d3d3998482ee7
Gitweb:        https://git.kernel.org/tip/aebd5354dd191860033f8599048d3d3998482ee7
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:54 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:48 +01:00

x86/resctrl: Add helper for setting CPU default properties

rdtgroup_rmdir_ctrl() and rdtgroup_rmdir_mon() set the per-CPU pqr_state for
CPUs that were part of the rmdir()'d group.

Another architecture might not have a 'pqr_state', its hardware may need the
values in a different format. MPAM's equivalent of RMID values are not unique,
and always need the CLOSID to be provided too.

There is only one caller that modifies a single value, (rdtgroup_rmdir_mon()).
MPAM always needs both CLOSID and RMID for the hardware value as these are
written to the same system register.

As rdtgroup_rmdir_mon() has the CLOSID on hand, only provide a helper to set
both values. These values are read by __resctrl_sched_in(), but may be written
by a different CPU without any locking, add READ/WRTE_ONCE() to avoid torn
values.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-10-james.morse@arm.com
---
 arch/x86/include/asm/resctrl.h         | 14 +++++++++++---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 20 ++++++++++++++------
 2 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 8b1b6ce..6908cd0 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -4,8 +4,9 @@
 
 #ifdef CONFIG_X86_CPU_RESCTRL
 
-#include <linux/sched.h>
 #include <linux/jump_label.h>
+#include <linux/percpu.h>
+#include <linux/sched.h>
 
 /*
  * This value can never be a valid CLOSID, and is used when mapping a
@@ -96,8 +97,8 @@ static inline void resctrl_arch_disable_mon(void)
 static inline void __resctrl_sched_in(struct task_struct *tsk)
 {
 	struct resctrl_pqr_state *state = this_cpu_ptr(&pqr_state);
-	u32 closid = state->default_closid;
-	u32 rmid = state->default_rmid;
+	u32 closid = READ_ONCE(state->default_closid);
+	u32 rmid = READ_ONCE(state->default_rmid);
 	u32 tmp;
 
 	/*
@@ -132,6 +133,13 @@ static inline unsigned int resctrl_arch_round_mon_val(unsigned int val)
 	return val * scale;
 }
 
+static inline void resctrl_arch_set_cpu_default_closid_rmid(int cpu, u32 closid,
+							    u32 rmid)
+{
+	WRITE_ONCE(per_cpu(pqr_state.default_closid, cpu), closid);
+	WRITE_ONCE(per_cpu(pqr_state.default_rmid, cpu), rmid);
+}
+
 static inline void resctrl_arch_set_closid_rmid(struct task_struct *tsk,
 						u32 closid, u32 rmid)
 {
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index cd8f65c..f706e5a 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -3731,14 +3731,21 @@ static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
 static int rdtgroup_rmdir_mon(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
 {
 	struct rdtgroup *prdtgrp = rdtgrp->mon.parent;
+	u32 closid, rmid;
 	int cpu;
 
 	/* Give any tasks back to the parent group */
 	rdt_move_group_tasks(rdtgrp, prdtgrp, tmpmask);
 
-	/* Update per cpu rmid of the moved CPUs first */
+	/*
+	 * Update per cpu closid/rmid of the moved CPUs first.
+	 * Note: the closid will not change, but the arch code still needs it.
+	 */
+	closid = prdtgrp->closid;
+	rmid = prdtgrp->mon.rmid;
 	for_each_cpu(cpu, &rdtgrp->cpu_mask)
-		per_cpu(pqr_state.default_rmid, cpu) = prdtgrp->mon.rmid;
+		resctrl_arch_set_cpu_default_closid_rmid(cpu, closid, rmid);
+
 	/*
 	 * Update the MSR on moved CPUs and CPUs which have moved
 	 * task running on them.
@@ -3771,6 +3778,7 @@ static int rdtgroup_ctrl_remove(struct rdtgroup *rdtgrp)
 
 static int rdtgroup_rmdir_ctrl(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
 {
+	u32 closid, rmid;
 	int cpu;
 
 	/* Give any tasks back to the default group */
@@ -3781,10 +3789,10 @@ static int rdtgroup_rmdir_ctrl(struct rdtgroup *rdtgrp, cpumask_var_t tmpmask)
 		   &rdtgroup_default.cpu_mask, &rdtgrp->cpu_mask);
 
 	/* Update per cpu closid and rmid of the moved CPUs first */
-	for_each_cpu(cpu, &rdtgrp->cpu_mask) {
-		per_cpu(pqr_state.default_closid, cpu) = rdtgroup_default.closid;
-		per_cpu(pqr_state.default_rmid, cpu) = rdtgroup_default.mon.rmid;
-	}
+	closid = rdtgroup_default.closid;
+	rmid = rdtgroup_default.mon.rmid;
+	for_each_cpu(cpu, &rdtgrp->cpu_mask)
+		resctrl_arch_set_cpu_default_closid_rmid(cpu, closid, rmid);
 
 	/*
 	 * Update the MSR on moved CPUs and CPUs which have moved

[tip: x86/cache] x86/resctrl: Generate default_ctrl instead of sharing it

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     dbc58f7eec4039ee8f3ec27b2b41d89500debfac
Gitweb:        https://git.kernel.org/tip/dbc58f7eec4039ee8f3ec27b2b41d89500debfac
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:53 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:44 +01:00

x86/resctrl: Generate default_ctrl instead of sharing it

The struct rdt_resource default_ctrl is used by both the architecture code for
resetting the hardware controls, and sometimes by the filesystem code as the
default value for the schema, unless the bandwidth software controller is in
use.

Having the default exposed by the architecture code causes unnecessary
duplication for each architecture as the default value must be specified, but
can be derived from other schema properties. Now that the maximum bandwidth is
explicitly described, resctrl can derive the default value from the schema
format and the other resource properties.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-9-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c        | 13 +++++--------
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  5 +++--
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    |  6 +++---
 include/linux/resctrl.h                   | 19 +++++++++++++++++--
 4 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 4504a12..d001ca4 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -155,7 +155,6 @@ static inline void cache_alloc_hsw_probe(void)
 		return;
 
 	hw_res->num_closid = 4;
-	r->default_ctrl = max_cbm;
 	r->cache.cbm_len = 20;
 	r->cache.shareable_bits = 0xc0000;
 	r->cache.min_cbm_bits = 2;
@@ -211,7 +210,6 @@ static __init bool __get_mem_config_intel(struct rdt_resource *r)
 	cpuid_count(0x00000010, 3, &eax.full, &ebx, &ecx, &edx.full);
 	hw_res->num_closid = edx.split.cos_max + 1;
 	max_delay = eax.split.max_delay + 1;
-	r->default_ctrl = MAX_MBA_BW;
 	r->membw.max_bw = MAX_MBA_BW;
 	r->membw.arch_needs_linear = true;
 	if (ecx & MBA_IS_LINEAR) {
@@ -250,7 +248,6 @@ static __init bool __rdt_get_mem_config_amd(struct rdt_resource *r)
 
 	cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx);
 	hw_res->num_closid = edx + 1;
-	r->default_ctrl = 1 << eax;
 	r->membw.max_bw = 1 << eax;
 
 	/* AMD does not use delay */
@@ -276,13 +273,13 @@ static void rdt_get_cache_alloc_cfg(int idx, struct rdt_resource *r)
 	union cpuid_0x10_1_eax eax;
 	union cpuid_0x10_x_ecx ecx;
 	union cpuid_0x10_x_edx edx;
-	u32 ebx;
+	u32 ebx, default_ctrl;
 
 	cpuid_count(0x00000010, idx, &eax.full, &ebx, &ecx.full, &edx.full);
 	hw_res->num_closid = edx.split.cos_max + 1;
 	r->cache.cbm_len = eax.split.cbm_len + 1;
-	r->default_ctrl = BIT_MASK(eax.split.cbm_len + 1) - 1;
-	r->cache.shareable_bits = ebx & r->default_ctrl;
+	default_ctrl = BIT_MASK(eax.split.cbm_len + 1) - 1;
+	r->cache.shareable_bits = ebx & default_ctrl;
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
 		r->cache.arch_has_sparse_bitmasks = ecx.split.noncont;
 	r->alloc_capable = true;
@@ -329,7 +326,7 @@ static u32 delay_bw_map(unsigned long bw, struct rdt_resource *r)
 		return MAX_MBA_BW - bw;
 
 	pr_warn_once("Non Linear delay-bw map not supported but queried\n");
-	return r->default_ctrl;
+	return MAX_MBA_BW;
 }
 
 static void mba_wrmsr_intel(struct msr_param *m)
@@ -438,7 +435,7 @@ static void setup_default_ctrlval(struct rdt_resource *r, u32 *dc)
 	 * For Memory Allocation: Set b/w requested to 100%
 	 */
 	for (i = 0; i < hw_res->num_closid; i++, dc++)
-		*dc = r->default_ctrl;
+		*dc = resctrl_get_default_ctrl(r);
 }
 
 static void ctrl_domain_free(struct rdt_hw_ctrl_domain *hw_dom)
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 23a01ea..5d87f27 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -113,8 +113,9 @@ static int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
  */
 static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
 {
-	unsigned long first_bit, zero_bit, val;
+	u32 supported_bits = BIT_MASK(r->cache.cbm_len) - 1;
 	unsigned int cbm_len = r->cache.cbm_len;
+	unsigned long first_bit, zero_bit, val;
 	int ret;
 
 	ret = kstrtoul(buf, 16, &val);
@@ -123,7 +124,7 @@ static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
 		return false;
 	}
 
-	if ((r->cache.min_cbm_bits > 0 && val == 0) || val > r->default_ctrl) {
+	if ((r->cache.min_cbm_bits > 0 && val == 0) || val > supported_bits) {
 		rdt_last_cmd_puts("Mask out of range\n");
 		return false;
 	}
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 1e0bae1..cd8f65c 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -978,7 +978,7 @@ static int rdt_default_ctrl_show(struct kernfs_open_file *of,
 	struct resctrl_schema *s = of->kn->parent->priv;
 	struct rdt_resource *r = s->res;
 
-	seq_printf(seq, "%x\n", r->default_ctrl);
+	seq_printf(seq, "%x\n", resctrl_get_default_ctrl(r));
 	return 0;
 }
 
@@ -2882,7 +2882,7 @@ static int reset_all_ctrls(struct rdt_resource *r)
 		hw_dom = resctrl_to_arch_ctrl_dom(d);
 
 		for (i = 0; i < hw_res->num_closid; i++)
-			hw_dom->ctrl_val[i] = r->default_ctrl;
+			hw_dom->ctrl_val[i] = resctrl_get_default_ctrl(r);
 		msr_param.dom = d;
 		smp_call_function_any(&d->hdr.cpu_mask, rdt_ctrl_update, &msr_param, 1);
 	}
@@ -3417,7 +3417,7 @@ static void rdtgroup_init_mba(struct rdt_resource *r, u32 closid)
 		}
 
 		cfg = &d->staged_config[CDP_NONE];
-		cfg->new_ctrl = r->default_ctrl;
+		cfg->new_ctrl = resctrl_get_default_ctrl(r);
 		cfg->have_new_ctrl = true;
 	}
 }
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 465f3cf..d16dc96 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -216,7 +216,6 @@ enum resctrl_schema_fmt {
  * @ctrl_domains:	RCU list of all control domains for this resource
  * @mon_domains:	RCU list of all monitor domains for this resource
  * @name:		Name to use in "schemata" file.
- * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
  * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
  * @cdp_capable:	Is the CDP feature available on this resource
@@ -233,7 +232,6 @@ struct rdt_resource {
 	struct list_head	ctrl_domains;
 	struct list_head	mon_domains;
 	char			*name;
-	u32			default_ctrl;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
 	bool			cdp_capable;
@@ -268,6 +266,23 @@ struct resctrl_schema {
 	u32				num_closid;
 };
 
+/**
+ * resctrl_get_default_ctrl() - Return the default control value for this
+ *                              resource.
+ * @r:		The resource whose default control type is queried.
+ */
+static inline u32 resctrl_get_default_ctrl(struct rdt_resource *r)
+{
+	switch (r->schema_fmt) {
+	case RESCTRL_SCHEMA_BITMAP:
+		return BIT_MASK(r->cache.cbm_len) - 1;
+	case RESCTRL_SCHEMA_RANGE:
+		return r->membw.max_bw;
+	}
+
+	return WARN_ON_ONCE(1);
+}
+
 /* The number of closid supported by this resource regardless of CDP */
 u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
 u32 resctrl_arch_system_num_rmid_idx(void);

[tip: x86/cache] x86/resctrl: Add max_bw to struct resctrl_membw

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     634ebb98b929443ea1a5502c93f26d01aedbd5c8
Gitweb:        https://git.kernel.org/tip/634ebb98b929443ea1a5502c93f26d01aedbd5c8
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:52 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:41 +01:00

x86/resctrl: Add max_bw to struct resctrl_membw

__rdt_get_mem_config_amd() and __get_mem_config_intel() both use the
default_ctrl property as a maximum value. This is because the MBA schema works
differently between these platforms. Doing this complicates determining
whether the default_ctrl property belongs to the arch code, or can be derived
from the schema format.

Deriving the maximum or default value from the schema format would avoid the
architecture code having to tell resctrl such obvious things as the maximum
percentage is 100, and the maximum bitmap is all ones.

Maximum bandwidth is always going to vary per platform. Add max_bw as
a special case. This is currently used for the maximum MBA percentage on Intel
platforms, but can be removed from the architecture code if 'percentage'
becomes a schema format resctrl supports directly.

This value isn't needed for other schema formats.

This will allow the default_ctrl to be generated from the schema properties
when it is needed.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-8-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c        | 2 ++
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 4 ++--
 include/linux/resctrl.h                   | 2 ++
 3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 754fb65..4504a12 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -212,6 +212,7 @@ static __init bool __get_mem_config_intel(struct rdt_resource *r)
 	hw_res->num_closid = edx.split.cos_max + 1;
 	max_delay = eax.split.max_delay + 1;
 	r->default_ctrl = MAX_MBA_BW;
+	r->membw.max_bw = MAX_MBA_BW;
 	r->membw.arch_needs_linear = true;
 	if (ecx & MBA_IS_LINEAR) {
 		r->membw.delay_linear = true;
@@ -250,6 +251,7 @@ static __init bool __rdt_get_mem_config_amd(struct rdt_resource *r)
 	cpuid_count(0x80000020, subleaf, &eax, &ebx, &ecx, &edx);
 	hw_res->num_closid = edx + 1;
 	r->default_ctrl = 1 << eax;
+	r->membw.max_bw = 1 << eax;
 
 	/* AMD does not use delay */
 	r->membw.delay_linear = false;
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 59610b2..23a01ea 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -63,9 +63,9 @@ static bool bw_validate(char *buf, u32 *data, struct rdt_resource *r)
 		return true;
 	}
 
-	if (bw < r->membw.min_bw || bw > r->default_ctrl) {
+	if (bw < r->membw.min_bw || bw > r->membw.max_bw) {
 		rdt_last_cmd_printf("MB value %u out of range [%d,%d]\n",
-				    bw, r->membw.min_bw, r->default_ctrl);
+				    bw, r->membw.min_bw, r->membw.max_bw);
 		return false;
 	}
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index e1a982a..465f3cf 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -165,6 +165,7 @@ enum membw_throttle_mode {
 /**
  * struct resctrl_membw - Memory bandwidth allocation related data
  * @min_bw:		Minimum memory bandwidth percentage user can request
+ * @max_bw:		Maximum memory bandwidth value, used as the reset value
  * @bw_gran:		Granularity at which the memory bandwidth is allocated
  * @delay_linear:	True if memory B/W delay is in linear scale
  * @arch_needs_linear:	True if we can't configure non-linear resources
@@ -175,6 +176,7 @@ enum membw_throttle_mode {
  */
 struct resctrl_membw {
 	u32				min_bw;
+	u32				max_bw;
 	u32				bw_gran;
 	u32				delay_linear;
 	bool				arch_needs_linear;

[tip: x86/cache] x86/resctrl: Remove data_width and the tabular format

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     43312b8ea1c61abbc5e3bdc87fe2e18f755d549d
Gitweb:        https://git.kernel.org/tip/43312b8ea1c61abbc5e3bdc87fe2e18f755d549d
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:51 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:36 +01:00

x86/resctrl: Remove data_width and the tabular format

The resctrl architecture code provides a data_width for the controls of each
resource. This is used to zero pad all control values in the schemata file so
they appear in columns. The same is done with the resource names to complete
the visual effect. e.g.

  | SMBA:0=2048
  |   L3:0=00ff

AMD platforms discover their maximum bandwidth for the MB resource from
firmware, but hard-code the data_width to 4. If the maximum bandwidth requires
more digits - the tabular format is silently broken.  This is also broken when
the mba_MBps mount option is used as the field width isn't updated. If new
schema are added resctrl will need to be able to determine the maximum width.
The benefit of this pretty-printing is questionable.

Instead of handling runtime discovery of the data_width for AMD platforms,
remove the feature. These fields are always zero padded so should be harmless
to remove if the whole field has been treated as a number.  In the above
example, this would now look like this:

  | SMBA:0=2048
  |   L3:0=ff

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-7-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c        | 26 +----------------------
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  3 +--
 arch/x86/kernel/cpu/resctrl/internal.h    |  2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 10 ++++++--
 include/linux/resctrl.h                   |  2 +--
 5 files changed, 10 insertions(+), 33 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 542503a..754fb65 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -44,12 +44,6 @@ static DEFINE_MUTEX(domain_list_lock);
 DEFINE_PER_CPU(struct resctrl_pqr_state, pqr_state);
 
 /*
- * Used to store the max resource name width and max resource data width
- * to display the schemata in a tabular format
- */
-int max_name_width, max_data_width;
-
-/*
  * Global boolean for rdt_alloc which is true if any
  * resource allocation is enabled.
  */
@@ -228,7 +222,6 @@ static __init bool __get_mem_config_intel(struct rdt_resource *r)
 			return false;
 		r->membw.arch_needs_linear = false;
 	}
-	r->data_width = 3;
 
 	if (boot_cpu_has(X86_FEATURE_PER_THREAD_MBA))
 		r->membw.throttle_mode = THREAD_THROTTLE_PER_THREAD;
@@ -269,8 +262,6 @@ static __init bool __rdt_get_mem_config_amd(struct rdt_resource *r)
 	r->membw.throttle_mode = THREAD_THROTTLE_UNDEFINED;
 	r->membw.min_bw = 0;
 	r->membw.bw_gran = 1;
-	/* Max value is 2048, Data width should be 4 in decimal */
-	r->data_width = 4;
 
 	r->alloc_capable = true;
 
@@ -290,7 +281,6 @@ static void rdt_get_cache_alloc_cfg(int idx, struct rdt_resource *r)
 	r->cache.cbm_len = eax.split.cbm_len + 1;
 	r->default_ctrl = BIT_MASK(eax.split.cbm_len + 1) - 1;
 	r->cache.shareable_bits = ebx & r->default_ctrl;
-	r->data_width = (r->cache.cbm_len + 3) / 4;
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
 		r->cache.arch_has_sparse_bitmasks = ecx.split.noncont;
 	r->alloc_capable = true;
@@ -786,20 +776,6 @@ static int resctrl_arch_offline_cpu(unsigned int cpu)
 	return 0;
 }
 
-/*
- * Choose a width for the resource name and resource data based on the
- * resource that has widest name and cbm.
- */
-static __init void rdt_init_padding(void)
-{
-	struct rdt_resource *r;
-
-	for_each_alloc_capable_rdt_resource(r) {
-		if (r->data_width > max_data_width)
-			max_data_width = r->data_width;
-	}
-}
-
 enum {
 	RDT_FLAG_CMT,
 	RDT_FLAG_MBM_TOTAL,
@@ -1102,8 +1078,6 @@ static int __init resctrl_late_init(void)
 	if (!get_rdt_resources())
 		return -ENODEV;
 
-	rdt_init_padding();
-
 	state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
 				  "x86/resctrl/cat:online:",
 				  resctrl_arch_online_cpu,
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index c763cb4..59610b2 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -487,8 +487,7 @@ static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int clo
 			ctrl_val = resctrl_arch_get_config(r, dom, closid,
 							   schema->conf_type);
 
-		seq_printf(s, schema->fmt_str, dom->hdr.id, max_data_width,
-			   ctrl_val);
+		seq_printf(s, schema->fmt_str, dom->hdr.id, ctrl_val);
 		sep = true;
 	}
 	seq_puts(s, "\n");
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index b5543bd..f975cd6 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -326,7 +326,7 @@ struct rdtgroup {
 /* List of all resource groups */
 extern struct list_head rdt_all_groups;
 
-extern int max_name_width, max_data_width;
+extern int max_name_width;
 
 int __init rdtgroup_init(void);
 void __exit rdtgroup_exit(void);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index e7862d0..1e0bae1 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -57,6 +57,12 @@ static struct kernfs_node *kn_mongrp;
 /* Kernel fs node for "mon_data" directory under root */
 static struct kernfs_node *kn_mondata;
 
+/*
+ * Used to store the max resource name width to display the schemata names in
+ * a tabular format.
+ */
+int max_name_width;
+
 static struct seq_buf last_cmd_status;
 static char last_cmd_status_buf[512];
 
@@ -2613,10 +2619,10 @@ static int schemata_list_add(struct rdt_resource *r, enum resctrl_conf_type type
 
 	switch (r->schema_fmt) {
 	case RESCTRL_SCHEMA_BITMAP:
-		s->fmt_str = "%d=%0*x";
+		s->fmt_str = "%d=%x";
 		break;
 	case RESCTRL_SCHEMA_RANGE:
-		s->fmt_str = "%d=%0*u";
+		s->fmt_str = "%d=%u";
 		break;
 	}
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 736b9a9..e1a982a 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -214,7 +214,6 @@ enum resctrl_schema_fmt {
  * @ctrl_domains:	RCU list of all control domains for this resource
  * @mon_domains:	RCU list of all monitor domains for this resource
  * @name:		Name to use in "schemata" file.
- * @data_width:		Character width of data when displaying
  * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
  * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
@@ -232,7 +231,6 @@ struct rdt_resource {
 	struct list_head	ctrl_domains;
 	struct list_head	mon_domains;
 	char			*name;
-	int			data_width;
 	u32			default_ctrl;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;

[tip: x86/cache] x86/resctrl: Use schema type to determine the schema format string

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     bb9343c8f2906ac7087a7f9560b37636c220551d
Gitweb:        https://git.kernel.org/tip/bb9343c8f2906ac7087a7f9560b37636c220551d
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:50 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:33 +01:00

x86/resctrl: Use schema type to determine the schema format string

Resctrl's architecture code gets to specify a format string that is
used when printing schema entries. This is expected to be one of two
values that the filesystem code supports.

Setting this format string allows the architecture code to change
the ABI resctrl presents to user-space.

Instead, use the schema format enum to choose which format string to
use.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-6-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c        |  4 ----
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 14 ++++++++++++++
 include/linux/resctrl.h                   |  4 ++--
 4 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index e9fe129..542503a 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -73,7 +73,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L3),
 			.mon_domains		= mon_domain_init(RDT_RESOURCE_L3),
 			.schema_fmt		= RESCTRL_SCHEMA_BITMAP,
-			.format_str		= "%d=%0*x",
 		},
 		.msr_base		= MSR_IA32_L3_CBM_BASE,
 		.msr_update		= cat_wrmsr,
@@ -86,7 +85,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_scope		= RESCTRL_L2_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L2),
 			.schema_fmt		= RESCTRL_SCHEMA_BITMAP,
-			.format_str		= "%d=%0*x",
 		},
 		.msr_base		= MSR_IA32_L2_CBM_BASE,
 		.msr_update		= cat_wrmsr,
@@ -99,7 +97,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_MBA),
 			.schema_fmt		= RESCTRL_SCHEMA_RANGE,
-			.format_str		= "%d=%*u",
 		},
 	},
 	[RDT_RESOURCE_SMBA] =
@@ -110,7 +107,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
 			.schema_fmt		= RESCTRL_SCHEMA_RANGE,
-			.format_str		= "%d=%*u",
 		},
 	},
 };
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index f4334f4..c763cb4 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -487,7 +487,7 @@ static void show_doms(struct seq_file *s, struct resctrl_schema *schema, int clo
 			ctrl_val = resctrl_arch_get_config(r, dom, closid,
 							   schema->conf_type);
 
-		seq_printf(s, r->format_str, dom->hdr.id, max_data_width,
+		seq_printf(s, schema->fmt_str, dom->hdr.id, max_data_width,
 			   ctrl_val);
 		sep = true;
 	}
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 3391ac8..e7862d0 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2611,6 +2611,20 @@ static int schemata_list_add(struct rdt_resource *r, enum resctrl_conf_type type
 	if (cl > max_name_width)
 		max_name_width = cl;
 
+	switch (r->schema_fmt) {
+	case RESCTRL_SCHEMA_BITMAP:
+		s->fmt_str = "%d=%0*x";
+		break;
+	case RESCTRL_SCHEMA_RANGE:
+		s->fmt_str = "%d=%0*u";
+		break;
+	}
+
+	if (WARN_ON_ONCE(!s->fmt_str)) {
+		kfree(s);
+		return -EINVAL;
+	}
+
 	INIT_LIST_HEAD(&s->list);
 	list_add(&s->list, &resctrl_schema_all);
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 3e1a413..736b9a9 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -216,7 +216,6 @@ enum resctrl_schema_fmt {
  * @name:		Name to use in "schemata" file.
  * @data_width:		Character width of data when displaying
  * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
- * @format_str:		Per resource format string to show domain value
  * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
  * @cdp_capable:	Is the CDP feature available on this resource
@@ -235,7 +234,6 @@ struct rdt_resource {
 	char			*name;
 	int			data_width;
 	u32			default_ctrl;
-	const char		*format_str;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
 	bool			cdp_capable;
@@ -253,6 +251,7 @@ struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l);
  *			   user-space
  * @list:	Member of resctrl_schema_all.
  * @name:	The name to use in the "schemata" file.
+ * @fmt_str:	Format string to show domain value.
  * @conf_type:	Whether this schema is specific to code/data.
  * @res:	The resource structure exported by the architecture to describe
  *		the hardware that is configured by this schema.
@@ -263,6 +262,7 @@ struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l);
 struct resctrl_schema {
 	struct list_head		list;
 	char				name[8];
+	const char			*fmt_str;
 	enum resctrl_conf_type		conf_type;
 	struct rdt_resource		*res;
 	u32				num_closid;

[tip: x86/cache] x86/resctrl: Use schema type to determine how to parse schema values

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     c24f5eab6b2689fd4e97a2d2fe963864036653e6
Gitweb:        https://git.kernel.org/tip/c24f5eab6b2689fd4e97a2d2fe963864036653e6
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:49 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:30 +01:00

x86/resctrl: Use schema type to determine how to parse schema values

Resctrl's architecture code gets to specify a function pointer that is used
when parsing schema entries. This is expected to be one of two helpers from
the filesystem code.

Setting this function pointer allows the architecture code to change the ABI
resctrl presents to user-space, and forces resctrl to expose these helpers.

Instead, add a schema format enum to choose which schema parser to use. This
allows the helpers to be made static and the structs used for passing
arguments moved out of shared headers.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-5-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c        |  8 +++---
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 32 ++++++++++++++++++----
 arch/x86/kernel/cpu/resctrl/internal.h    | 10 +-------
 include/linux/resctrl.h                   | 17 ++++++++----
 4 files changed, 43 insertions(+), 24 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 8ef2e44..e9fe129 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -72,7 +72,7 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.mon_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L3),
 			.mon_domains		= mon_domain_init(RDT_RESOURCE_L3),
-			.parse_ctrlval		= parse_cbm,
+			.schema_fmt		= RESCTRL_SCHEMA_BITMAP,
 			.format_str		= "%d=%0*x",
 		},
 		.msr_base		= MSR_IA32_L3_CBM_BASE,
@@ -85,7 +85,7 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.name			= "L2",
 			.ctrl_scope		= RESCTRL_L2_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L2),
-			.parse_ctrlval		= parse_cbm,
+			.schema_fmt		= RESCTRL_SCHEMA_BITMAP,
 			.format_str		= "%d=%0*x",
 		},
 		.msr_base		= MSR_IA32_L2_CBM_BASE,
@@ -98,7 +98,7 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.name			= "MB",
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_MBA),
-			.parse_ctrlval		= parse_bw,
+			.schema_fmt		= RESCTRL_SCHEMA_RANGE,
 			.format_str		= "%d=%*u",
 		},
 	},
@@ -109,7 +109,7 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.name			= "SMBA",
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
-			.parse_ctrlval		= parse_bw,
+			.schema_fmt		= RESCTRL_SCHEMA_RANGE,
 			.format_str		= "%d=%*u",
 		},
 	},
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 4af27ef..f4334f4 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -23,6 +23,15 @@
 
 #include "internal.h"
 
+struct rdt_parse_data {
+	struct rdtgroup		*rdtgrp;
+	char			*buf;
+};
+
+typedef int (ctrlval_parser_t)(struct rdt_parse_data *data,
+			       struct resctrl_schema *s,
+			       struct rdt_ctrl_domain *d);
+
 /*
  * Check whether MBA bandwidth percentage value is correct. The value is
  * checked against the minimum and max bandwidth values specified by the
@@ -64,8 +73,8 @@ static bool bw_validate(char *buf, u32 *data, struct rdt_resource *r)
 	return true;
 }
 
-int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
-	     struct rdt_ctrl_domain *d)
+static int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
+		    struct rdt_ctrl_domain *d)
 {
 	struct resctrl_staged_config *cfg;
 	u32 closid = data->rdtgrp->closid;
@@ -143,8 +152,8 @@ static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
  * Read one cache bit mask (hex). Check that it is valid for the current
  * resource type.
  */
-int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
-	      struct rdt_ctrl_domain *d)
+static int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
+		     struct rdt_ctrl_domain *d)
 {
 	struct rdtgroup *rdtgrp = data->rdtgrp;
 	struct resctrl_staged_config *cfg;
@@ -210,6 +219,7 @@ static int parse_line(char *line, struct resctrl_schema *s,
 		      struct rdtgroup *rdtgrp)
 {
 	enum resctrl_conf_type t = s->conf_type;
+	ctrlval_parser_t *parse_ctrlval = NULL;
 	struct resctrl_staged_config *cfg;
 	struct rdt_resource *r = s->res;
 	struct rdt_parse_data data;
@@ -220,6 +230,18 @@ static int parse_line(char *line, struct resctrl_schema *s,
 	/* Walking r->domains, ensure it can't race with cpuhp */
 	lockdep_assert_cpus_held();
 
+	switch (r->schema_fmt) {
+	case RESCTRL_SCHEMA_BITMAP:
+		parse_ctrlval = &parse_cbm;
+		break;
+	case RESCTRL_SCHEMA_RANGE:
+		parse_ctrlval = &parse_bw;
+		break;
+	}
+
+	if (WARN_ON_ONCE(!parse_ctrlval))
+		return -EINVAL;
+
 	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
 	    (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)) {
 		rdt_last_cmd_puts("Cannot pseudo-lock MBA resource\n");
@@ -240,7 +262,7 @@ next:
 		if (d->hdr.id == dom_id) {
 			data.buf = dom;
 			data.rdtgrp = rdtgrp;
-			if (r->parse_ctrlval(&data, s, d))
+			if (parse_ctrlval(&data, s, d))
 				return -EINVAL;
 			if (rdtgrp->mode ==  RDT_MODE_PSEUDO_LOCKSETUP) {
 				cfg = &d->staged_config[t];
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 75252a7..b5543bd 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -459,11 +459,6 @@ static inline bool is_mbm_event(int e)
 		e <= QOS_L3_MBM_LOCAL_EVENT_ID);
 }
 
-struct rdt_parse_data {
-	struct rdtgroup		*rdtgrp;
-	char			*buf;
-};
-
 /**
  * struct rdt_hw_resource - arch private attributes of a resctrl resource
  * @r_resctrl:		Attributes of the resource used directly by resctrl.
@@ -500,11 +495,6 @@ static inline struct rdt_hw_resource *resctrl_to_arch_res(struct rdt_resource *r
 	return container_of(r, struct rdt_hw_resource, r_resctrl);
 }
 
-int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
-	      struct rdt_ctrl_domain *d);
-int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
-	     struct rdt_ctrl_domain *d);
-
 extern struct mutex rdtgroup_mutex;
 
 extern struct rdt_hw_resource rdt_resources_all[];
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 496ddca..3e1a413 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -183,7 +183,6 @@ struct resctrl_membw {
 	u32				*mb_map;
 };
 
-struct rdt_parse_data;
 struct resctrl_schema;
 
 enum resctrl_scope {
@@ -193,6 +192,16 @@ enum resctrl_scope {
 };
 
 /**
+ * enum resctrl_schema_fmt - The format user-space provides for a schema.
+ * @RESCTRL_SCHEMA_BITMAP:	The schema is a bitmap in hex.
+ * @RESCTRL_SCHEMA_RANGE:	The schema is a decimal number.
+ */
+enum resctrl_schema_fmt {
+	RESCTRL_SCHEMA_BITMAP,
+	RESCTRL_SCHEMA_RANGE,
+};
+
+/**
  * struct rdt_resource - attributes of a resctrl resource
  * @rid:		The index of the resource
  * @alloc_capable:	Is allocation available on this machine
@@ -208,7 +217,7 @@ enum resctrl_scope {
  * @data_width:		Character width of data when displaying
  * @default_ctrl:	Specifies default cache cbm or memory B/W percent.
  * @format_str:		Per resource format string to show domain value
- * @parse_ctrlval:	Per resource function pointer to parse control values
+ * @schema_fmt:		Which format string and parser is used for this schema.
  * @evt_list:		List of monitoring events
  * @cdp_capable:	Is the CDP feature available on this resource
  */
@@ -227,9 +236,7 @@ struct rdt_resource {
 	int			data_width;
 	u32			default_ctrl;
 	const char		*format_str;
-	int			(*parse_ctrlval)(struct rdt_parse_data *data,
-						 struct resctrl_schema *s,
-						 struct rdt_ctrl_domain *d);
+	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
 	bool			cdp_capable;
 };

[tip: x86/cache] x86/resctrl: Remove fflags from struct rdt_resource

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     131dab13a82d9edd97dd96d98d2919f56f339331
Gitweb:        https://git.kernel.org/tip/131dab13a82d9edd97dd96d98d2919f56f339331
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:48 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:26 +01:00

x86/resctrl: Remove fflags from struct rdt_resource

The resctrl arch code specifies whether a resource controls a cache or memory
using the fflags field. This field is then used by resctrl to determine which
files should be exposed in the filesystem.

Allowing the architecture to pick this value means the RFTYPE_ flags have to
be in a shared header, and allows an architecture to create a combination that
resctrl does not support.

Remove the fflags field, and pick the value based on the resource id.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-4-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c     |  4 ----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 18 ++++++++++++++++--
 include/linux/resctrl.h                |  2 --
 3 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 12b4131..8ef2e44 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -74,7 +74,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.mon_domains		= mon_domain_init(RDT_RESOURCE_L3),
 			.parse_ctrlval		= parse_cbm,
 			.format_str		= "%d=%0*x",
-			.fflags			= RFTYPE_RES_CACHE,
 		},
 		.msr_base		= MSR_IA32_L3_CBM_BASE,
 		.msr_update		= cat_wrmsr,
@@ -88,7 +87,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_L2),
 			.parse_ctrlval		= parse_cbm,
 			.format_str		= "%d=%0*x",
-			.fflags			= RFTYPE_RES_CACHE,
 		},
 		.msr_base		= MSR_IA32_L2_CBM_BASE,
 		.msr_update		= cat_wrmsr,
@@ -102,7 +100,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_MBA),
 			.parse_ctrlval		= parse_bw,
 			.format_str		= "%d=%*u",
-			.fflags			= RFTYPE_RES_MB,
 		},
 	},
 	[RDT_RESOURCE_SMBA] =
@@ -114,7 +111,6 @@ struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
 			.parse_ctrlval		= parse_bw,
 			.format_str		= "%d=%*u",
-			.fflags			= RFTYPE_RES_MB,
 		},
 	},
 };
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 45093b9..3391ac8 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2165,6 +2165,20 @@ static int rdtgroup_mkdir_info_resdir(void *priv, char *name,
 	return ret;
 }
 
+static unsigned long fflags_from_resource(struct rdt_resource *r)
+{
+	switch (r->rid) {
+	case RDT_RESOURCE_L3:
+	case RDT_RESOURCE_L2:
+		return RFTYPE_RES_CACHE;
+	case RDT_RESOURCE_MBA:
+	case RDT_RESOURCE_SMBA:
+		return RFTYPE_RES_MB;
+	}
+
+	return WARN_ON_ONCE(1);
+}
+
 static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
 {
 	struct resctrl_schema *s;
@@ -2185,14 +2199,14 @@ static int rdtgroup_create_info_dir(struct kernfs_node *parent_kn)
 	/* loop over enabled controls, these are all alloc_capable */
 	list_for_each_entry(s, &resctrl_schema_all, list) {
 		r = s->res;
-		fflags = r->fflags | RFTYPE_CTRL_INFO;
+		fflags = fflags_from_resource(r) | RFTYPE_CTRL_INFO;
 		ret = rdtgroup_mkdir_info_resdir(s, s->name, fflags);
 		if (ret)
 			goto out_destroy;
 	}
 
 	for_each_mon_capable_rdt_resource(r) {
-		fflags = r->fflags | RFTYPE_MON_INFO;
+		fflags = fflags_from_resource(r) | RFTYPE_MON_INFO;
 		sprintf(name, "%s_MON", r->name);
 		ret = rdtgroup_mkdir_info_resdir(r, name, fflags);
 		if (ret)
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 37279e2..496ddca 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -210,7 +210,6 @@ enum resctrl_scope {
  * @format_str:		Per resource format string to show domain value
  * @parse_ctrlval:	Per resource function pointer to parse control values
  * @evt_list:		List of monitoring events
- * @fflags:		flags to choose base and info files
  * @cdp_capable:	Is the CDP feature available on this resource
  */
 struct rdt_resource {
@@ -232,7 +231,6 @@ struct rdt_resource {
 						 struct resctrl_schema *s,
 						 struct rdt_ctrl_domain *d);
 	struct list_head	evt_list;
-	unsigned long		fflags;
 	bool			cdp_capable;
 };
 

[tip: x86/cache] x86/resctrl: Add a helper to avoid reaching into the arch code resource list

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     3c021531131c9ee5df5da739819a515326ee9570
Gitweb:        https://git.kernel.org/tip/3c021531131c9ee5df5da739819a515326ee9570
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:47 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:22:22 +01:00

x86/resctrl: Add a helper to avoid reaching into the arch code resource list

Resctrl occasionally wants to know something about a specific resource, in
these cases it reaches into the arch code's rdt_resources_all[] array.

Once the filesystem parts of resctrl are moved to /fs/, this means it will
need visibility of the architecture specific struct rdt_hw_resource
definition, and the array of all resources.  All architectures would also need
a r_resctrl member in this struct.

Instead, abstract this via a helper to allow architectures to do different
things here. Move the level enum to the resctrl header and add a helper to
retrieve the struct rdt_resource by 'rid'.

resctrl_arch_get_resource() should not return NULL for any value in the enum,
it may instead return a dummy resource that is !alloc_enabled && !mon_enabled.

Co-developed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-3-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/core.c        | 12 ++++++++++--
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  2 +-
 arch/x86/kernel/cpu/resctrl/internal.h    | 10 ----------
 arch/x86/kernel/cpu/resctrl/monitor.c     |  8 ++++----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    | 14 +++++++-------
 include/linux/resctrl.h                   | 17 +++++++++++++++++
 6 files changed, 39 insertions(+), 24 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 3d1735e..12b4131 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -62,7 +62,7 @@ static void mba_wrmsr_amd(struct msr_param *m);
 #define ctrl_domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].r_resctrl.ctrl_domains)
 #define mon_domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].r_resctrl.mon_domains)
 
-struct rdt_hw_resource rdt_resources_all[] = {
+struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = {
 	[RDT_RESOURCE_L3] =
 	{
 		.r_resctrl = {
@@ -127,6 +127,14 @@ u32 resctrl_arch_system_num_rmid_idx(void)
 	return r->num_rmid;
 }
 
+struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l)
+{
+	if (l >= RDT_NUM_RESOURCES)
+		return NULL;
+
+	return &rdt_resources_all[l].r_resctrl;
+}
+
 /*
  * cache_alloc_hsw_probe() - Have to probe for Intel haswell server CPUs
  * as they do not have CPUID enumeration support for Cache allocation.
@@ -174,7 +182,7 @@ static inline void cache_alloc_hsw_probe(void)
 bool is_mba_sc(struct rdt_resource *r)
 {
 	if (!r)
-		return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.mba_sc;
+		r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 
 	/*
 	 * The software controller support is only applicable to MBA resource.
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 5363511..4af27ef 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -649,7 +649,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 	resid = md.u.rid;
 	domid = md.u.domid;
 	evtid = md.u.evtid;
-	r = &rdt_resources_all[resid].r_resctrl;
+	r = resctrl_arch_get_resource(resid);
 
 	if (md.u.sum) {
 		/*
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 20c898f..75252a7 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -512,16 +512,6 @@ extern struct rdtgroup rdtgroup_default;
 extern struct dentry *debugfs_resctrl;
 extern enum resctrl_event_id mba_mbps_default_event;
 
-enum resctrl_res_level {
-	RDT_RESOURCE_L3,
-	RDT_RESOURCE_L2,
-	RDT_RESOURCE_MBA,
-	RDT_RESOURCE_SMBA,
-
-	/* Must be the last */
-	RDT_NUM_RESOURCES,
-};
-
 static inline struct rdt_resource *resctrl_inc(struct rdt_resource *res)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(res);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 94a1d97..58b5b21 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -365,7 +365,7 @@ static void limbo_release_entry(struct rmid_entry *entry)
  */
 void __check_limbo(struct rdt_mon_domain *d, bool force_free)
 {
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	u32 idx_limit = resctrl_arch_system_num_rmid_idx();
 	struct rmid_entry *entry;
 	u32 idx, cur_idx = 1;
@@ -521,7 +521,7 @@ int alloc_rmid(u32 closid)
 
 static void add_rmid_to_limbo(struct rmid_entry *entry)
 {
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	struct rdt_mon_domain *d;
 	u32 idx;
 
@@ -761,7 +761,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_mon_domain *dom_mbm)
 	struct rdtgroup *entry;
 	u32 cur_bw, user_bw;
 
-	r_mba = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+	r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 	evt_id = rgrp->mba_mbps_event;
 
 	closid = rgrp->closid;
@@ -925,7 +925,7 @@ void mbm_handle_overflow(struct work_struct *work)
 	if (!resctrl_mounted || !resctrl_arch_mon_capable())
 		goto out_unlock;
 
-	r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	d = container_of(work, struct rdt_mon_domain, mbm_over.work);
 
 	list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) {
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 04b653d..45093b9 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2256,7 +2256,7 @@ static void l2_qos_cfg_update(void *arg)
 
 static inline bool is_mba_linear(void)
 {
-	return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.delay_linear;
+	return resctrl_arch_get_resource(RDT_RESOURCE_MBA)->membw.delay_linear;
 }
 
 static int set_cache_qos_cfg(int level, bool enable)
@@ -2346,8 +2346,8 @@ static void mba_sc_domain_destroy(struct rdt_resource *r,
  */
 static bool supports_mba_mbps(void)
 {
-	struct rdt_resource *rmbm = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+	struct rdt_resource *rmbm = resctrl_arch_get_resource(RDT_RESOURCE_L3);
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 
 	return (is_mbm_enabled() &&
 		r->alloc_capable && is_mba_linear() &&
@@ -2360,7 +2360,7 @@ static bool supports_mba_mbps(void)
  */
 static int set_mba_sc(bool mba_sc)
 {
-	struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 	u32 num_closid = resctrl_arch_get_num_closid(r);
 	struct rdt_ctrl_domain *d;
 	unsigned long fflags;
@@ -2714,7 +2714,7 @@ static int rdt_get_tree(struct fs_context *fc)
 		resctrl_mounted = true;
 
 	if (is_mbm_enabled()) {
-		r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+		r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 		list_for_each_entry(dom, &r->mon_domains, hdr.list)
 			mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL,
 						   RESCTRL_PICK_ANY_CPU);
@@ -3951,7 +3951,7 @@ static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf)
 	if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2))
 		seq_puts(seq, ",cdpl2");
 
-	if (is_mba_sc(&rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl))
+	if (is_mba_sc(resctrl_arch_get_resource(RDT_RESOURCE_MBA)))
 		seq_puts(seq, ",mba_MBps");
 
 	if (resctrl_debug)
@@ -4151,7 +4151,7 @@ static void clear_childcpus(struct rdtgroup *r, unsigned int cpu)
 
 void resctrl_offline_cpu(unsigned int cpu)
 {
-	struct rdt_resource *l3 = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+	struct rdt_resource *l3 = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	struct rdt_mon_domain *d;
 	struct rdtgroup *rdtgrp;
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index d94abba..37279e2 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -37,6 +37,16 @@ enum resctrl_conf_type {
 	CDP_DATA,
 };
 
+enum resctrl_res_level {
+	RDT_RESOURCE_L3,
+	RDT_RESOURCE_L2,
+	RDT_RESOURCE_MBA,
+	RDT_RESOURCE_SMBA,
+
+	/* Must be the last */
+	RDT_NUM_RESOURCES,
+};
+
 #define CDP_NUM_TYPES	(CDP_DATA + 1)
 
 /*
@@ -226,6 +236,13 @@ struct rdt_resource {
 	bool			cdp_capable;
 };
 
+/*
+ * Get the resource that exists at this level. If the level is not supported
+ * a dummy/not-capable resource can be returned. Levels >= RDT_NUM_RESOURCES
+ * will return NULL.
+ */
+struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l);
+
 /**
  * struct resctrl_schema - configuration abilities of a resource presented to
  *			   user-space

[tip: x86/cache] x86/resctrl: Fix allocation of cleanest CLOSID on platforms with no monitors

[tip-bot2 for James Morse]

The following commit has been merged into the x86/cache branch of tip:

Commit-ID:     a121798ae669351ec0697c94f71c3a692b2a755b
Gitweb:        https://git.kernel.org/tip/a121798ae669351ec0697c94f71c3a692b2a755b
Author:        James Morse <james.morse@arm.com>
AuthorDate:    Tue, 11 Mar 2025 18:36:46 
Committer:     Borislav Petkov (AMD) <bp@alien8.de>
CommitterDate: Wed, 12 Mar 2025 12:21:48 +01:00

x86/resctrl: Fix allocation of cleanest CLOSID on platforms with no monitors

Commit

  6eac36bb9eb0 ("x86/resctrl: Allocate the cleanest CLOSID by searching closid_num_dirty_rmid")

added logic that causes resctrl to search for the CLOSID with the fewest dirty
cache lines when creating a new control group, if requested by the arch code.
This depends on the values read from the llc_occupancy counters. The logic is
applicable to architectures where the CLOSID effectively forms part of the
monitoring identifier and so do not allow complete freedom to choose an unused
monitoring identifier for a given CLOSID.

This support missed that some platforms may not have these counters.  This
causes a NULL pointer dereference when creating a new control group as the
array was not allocated by dom_data_init().

As this feature isn't necessary on platforms that don't have cache occupancy
monitors, add this to the check that occurs when a new control group is
allocated.

Fixes: 6eac36bb9eb0 ("x86/resctrl: Allocate the cleanest CLOSID by searching closid_num_dirty_rmid")
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-2-james.morse@arm.com
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 6419e04..04b653d 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -157,7 +157,8 @@ static int closid_alloc(void)
 
 	lockdep_assert_held(&rdtgroup_mutex);
 
-	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) {
+	if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID) &&
+	    is_llc_occupancy_enabled()) {
 		cleanest_closid = resctrl_find_cleanest_closid();
 		if (cleanest_closid < 0)
 			return cleanest_closid;