[PATCH v4 00/39] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[PATCH v4 00/39] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[James Morse]

Changes since v3?
The behaviour round fflags has changed to remove more static properties of the
schema that the arch code had to set, and to generate the 'its a cache' flags
from the resource type.
The trace file is now split in two, one file moves the other doesn't.
Otherwise changes are noted on each patch.

~

This is the final series that allows other architectures to implement resctrl.
The final patch to move the code has been omited, but can be generated using
the python script at the end of the series.
The final move is a bit of a monster. I don't expect that to get merged as part
of this series - we should wait for it to make less impact on other series.

Otherwise 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.

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.

After this, I can start posting the MPAM driver to make use of resctrl on arm64.
(What's MPAM? See the cover letter of the first series. [1])

This series is based on v6.11-rc1 and can be retrieved from:
https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/move_to_fs/v4

As ever - bugs welcome,
Thanks,

James

[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 (39):
  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: Move data_width to be a schema property
  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: Export resctrl fs's init function
  x86/resctrl: Wrap resctrl_arch_find_domain() around rdt_find_domain()
  x86/resctrl: Move resctrl types to a separate header
  x86/resctrl: Add a resctrl helper to reset all the resources
  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: Export 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 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 thread_throttle_mode_init() to be managed by resctrl
  x86/resctrl: Move get_config_index() to a header
  x86/resctrl: Claim get_{mon,ctrl}_domain_from_cpu() helpers for
    resctrl
  x86/resctrl: Describe resctrl's bitmap size assumptions
  x86/resctrl: Rename resctrl_sched_in() to begin with "resctrl_arch_"
  x86/resctrl: resctrl_exit() teardown resctrl but leave the mount point
  x86/resctrl: Drop __init/__exit on assorted symbols
  x86/resctrl: Move is_mba_sc() out of core.c
  x86/resctrl: Add end-marker to the resctrl_event_id enum
  x86/resctrl: Remove a newline to avoid confusing the code move script
  x86/resctrl: Split trace.h
  fs/resctrl: Add boiler plate for external resctrl code
  x86/resctrl: Move the filesystem bits to headers visible to fs/resctrl
  x86/resctrl: Add python script to move resctrl code to /fs/resctrl

 MAINTAINERS                                   |   2 +
 arch/Kconfig                                  |   8 +
 arch/x86/Kconfig                              |  12 +-
 arch/x86/include/asm/resctrl.h                |  45 +-
 arch/x86/kernel/cpu/resctrl/Makefile          |   8 +-
 arch/x86/kernel/cpu/resctrl/core.c            | 174 ++--
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c     |  67 +-
 arch/x86/kernel/cpu/resctrl/internal.h        | 215 +----
 arch/x86/kernel/cpu/resctrl/monitor.c         | 104 ++-
 arch/x86/kernel/cpu/resctrl/monitor_trace.h   |  31 +
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c     |  60 +-
 .../resctrl/{trace.h => pseudo_lock_trace.h}  |  24 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c        | 276 +++++--
 arch/x86/kernel/process_32.c                  |   2 +-
 arch/x86/kernel/process_64.c                  |   2 +-
 fs/Kconfig                                    |   1 +
 fs/Makefile                                   |   1 +
 fs/resctrl/Kconfig                            |  37 +
 fs/resctrl/Makefile                           |   6 +
 fs/resctrl/ctrlmondata.c                      |   0
 fs/resctrl/internal.h                         |   0
 fs/resctrl/monitor.c                          |   0
 fs/resctrl/monitor_trace.h                    |   0
 fs/resctrl/pseudo_lock.c                      |   0
 fs/resctrl/pseudo_lock_trace.h                |   0
 fs/resctrl/rdtgroup.c                         |   0
 include/linux/resctrl.h                       | 244 +++++-
 include/linux/resctrl_types.h                 |  59 ++
 resctrl_copy_pasta.py                         | 779 ++++++++++++++++++
 29 files changed, 1655 insertions(+), 502 deletions(-)
 create mode 100644 arch/x86/kernel/cpu/resctrl/monitor_trace.h
 rename arch/x86/kernel/cpu/resctrl/{trace.h => pseudo_lock_trace.h} (56%)
 create mode 100644 fs/resctrl/Kconfig
 create mode 100644 fs/resctrl/Makefile
 create mode 100644 fs/resctrl/ctrlmondata.c
 create mode 100644 fs/resctrl/internal.h
 create mode 100644 fs/resctrl/monitor.c
 create mode 100644 fs/resctrl/monitor_trace.h
 create mode 100644 fs/resctrl/pseudo_lock.c
 create mode 100644 fs/resctrl/pseudo_lock_trace.h
 create mode 100644 fs/resctrl/rdtgroup.c
 create mode 100644 include/linux/resctrl_types.h
 create mode 100644 resctrl_copy_pasta.py

-- 
2.39.2

[PATCH v4 01/39] 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
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.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 d7163b764c62..2d48db66fca8 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -148,7 +148,8 @@ 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;
-- 
2.39.2

[PATCH v4 02/39] 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: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
---
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        | 10 +++++++++-
 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, 38 insertions(+), 23 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 1930fce9dfe9..d7ae77a8f6f4 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -119,6 +119,14 @@ struct rdt_hw_resource rdt_resources_all[] = {
 	},
 };
 
+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.
@@ -166,7 +174,7 @@ 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 50fa1fe9a073..e078bfe3840d 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -574,7 +574,7 @@ 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 955999aecfca..b5a34a3fa599 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -509,16 +509,6 @@ extern struct rdt_hw_resource rdt_resources_all[];
 extern struct rdtgroup rdtgroup_default;
 extern struct dentry *debugfs_resctrl;
 
-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 851b561850e0..00d906a1f51c 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;
 
@@ -760,7 +760,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_mon_domain *dom_mbm)
 	if (!is_mbm_local_enabled())
 		return;
 
-	r_mba = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl;
+	r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 
 	closid = rgrp->closid;
 	rmid = rgrp->mon.rmid;
@@ -929,7 +929,7 @@ 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 2d48db66fca8..6225d0b7e9ee 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2251,7 +2251,7 @@ 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)
@@ -2341,8 +2341,8 @@ 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_local_enabled() &&
 		r->alloc_capable && is_mba_linear() &&
@@ -2355,7 +2355,7 @@ 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;
 	int i;
@@ -2703,7 +2703,7 @@ 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);
@@ -3938,7 +3938,7 @@ 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)
@@ -4138,7 +4138,7 @@ 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 b0875b99e811..7563628464e5 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
-- 
2.39.2

[PATCH v4 03/39] 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 exopsed 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>
---
 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 d7ae77a8f6f4..9ca542a8e2d4 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[] = {
 			.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[] = {
 			.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[] = {
 			.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[] = {
 			.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 6225d0b7e9ee..50d92e5594a3 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2160,6 +2160,20 @@ static int rdtgroup_mkdir_info_resdir(void *priv, char *name,
 	return ret;
 }
 
+static u32 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;
@@ -2180,14 +2194,14 @@ 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 7563628464e5..94dcd72509f5 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;
 };
 
-- 
2.39.2

[PATCH v4 04/39] 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
---
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        | 13 ++++++---
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 33 +++++++++++++++++++----
 arch/x86/kernel/cpu/resctrl/internal.h    | 10 -------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    |  4 +--
 include/linux/resctrl.h                   | 19 +++++++++----
 5 files changed, 53 insertions(+), 26 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 9ca542a8e2d4..57c88e1c2adf 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[] = {
 			.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[] = {
 			.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 +98,11 @@ struct rdt_hw_resource rdt_resources_all[] = {
 			.name			= "MB",
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_MBA),
-			.parse_ctrlval		= parse_bw,
+			/*
+			 * MBA schema_fmt is modified by
+			 * __rdt_get_mem_config_amd()
+			 */
+			.schema_fmt		= RESCTRL_SCHEMA_PERCENTAGE,
 			.format_str		= "%d=%*u",
 		},
 	},
@@ -109,7 +113,7 @@ struct rdt_hw_resource rdt_resources_all[] = {
 			.name			= "SMBA",
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
-			.parse_ctrlval		= parse_bw,
+			.schema_fmt		= RESCTRL_SCHEMA_MBPS,
 			.format_str		= "%d=%*u",
 		},
 	},
@@ -251,6 +255,7 @@ static 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->schema_fmt = RESCTRL_SCHEMA_MBPS;
 
 	/* 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 e078bfe3840d..8d02d563bb60 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
@@ -59,8 +68,8 @@ static bool bw_validate(char *buf, unsigned long *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;
@@ -138,8 +147,8 @@ 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;
@@ -195,6 +204,19 @@ int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
 	return 0;
 }
 
+static ctrlval_parser_t *get_parser(struct rdt_resource *r)
+{
+	switch (r->schema_fmt) {
+	case RESCTRL_SCHEMA_BITMAP:
+		return &parse_cbm;
+	case RESCTRL_SCHEMA_PERCENTAGE:
+	case RESCTRL_SCHEMA_MBPS:
+		return &parse_bw;
+	}
+
+	return NULL;
+}
+
 /*
  * For each domain in this resource we expect to find a series of:
  *	id=mask
@@ -204,6 +226,7 @@ int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
 static int parse_line(char *line, struct resctrl_schema *s,
 		      struct rdtgroup *rdtgrp)
 {
+	ctrlval_parser_t *parse_ctrlval = get_parser(s->res);
 	enum resctrl_conf_type t = s->conf_type;
 	struct resctrl_staged_config *cfg;
 	struct rdt_resource *r = s->res;
@@ -235,7 +258,7 @@ 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 b5a34a3fa599..ffcade365070 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -457,11 +457,6 @@ 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.
@@ -498,11 +493,6 @@ 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/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 50d92e5594a3..11153271cbdc 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2194,14 +2194,14 @@ 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 =  fflags_from_resource(r) | 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 =  fflags_from_resource(r) | 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 94dcd72509f5..77fec8970d40 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 +191,18 @@ 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_PERCENTAGE:	The schema is a decimal percentage value.
+ * @RESCTRL_SCHEMA_MBPS:	The schema is a decimal MBps value.
+ */
+enum resctrl_schema_fmt {
+	RESCTRL_SCHEMA_BITMAP,
+	RESCTRL_SCHEMA_PERCENTAGE,
+	RESCTRL_SCHEMA_MBPS,
+};
+
 /**
  * struct rdt_resource - attributes of a resctrl resource
  * @rid:		The index of the resource
@@ -208,7 +219,7 @@ 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 +238,7 @@ 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;
 };
-- 
2.39.2

[PATCH v4 05/39] 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
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
---
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    | 12 ++++++++++++
 include/linux/resctrl.h                   |  4 ++--
 4 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 57c88e1c2adf..f16014ee48aa 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[] = {
 			.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[] = {
 			.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,
@@ -103,7 +101,6 @@ struct rdt_hw_resource rdt_resources_all[] = {
 			 * __rdt_get_mem_config_amd()
 			 */
 			.schema_fmt		= RESCTRL_SCHEMA_PERCENTAGE,
-			.format_str		= "%d=%*u",
 		},
 	},
 	[RDT_RESOURCE_SMBA] =
@@ -114,7 +111,6 @@ struct rdt_hw_resource rdt_resources_all[] = {
 			.ctrl_scope		= RESCTRL_L3_CACHE,
 			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
 			.schema_fmt		= RESCTRL_SCHEMA_MBPS,
-			.format_str		= "%d=%*u",
 		},
 	},
 };
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 8d02d563bb60..1d9ad4d82bf0 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -483,7 +483,7 @@ 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 11153271cbdc..1ce851447923 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2600,6 +2600,18 @@ 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_PERCENTAGE:
+		s->fmt_str = "%d=%0*u";
+		break;
+	case RESCTRL_SCHEMA_MBPS:
+		s->fmt_str = "%d=%0*u";
+		break;
+	}
+
 	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 77fec8970d40..1624d4b15b52 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -218,7 +218,6 @@ 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
@@ -237,7 +236,6 @@ 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;
@@ -255,6 +253,7 @@ 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.
@@ -265,6 +264,7 @@ 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;
-- 
2.39.2

[PATCH v4 06/39] x86/resctrl: Move data_width to be a schema property

[James Morse]

The resctrl architecture code gets to specify the width of the schema
entries that are used by resctrl. These are determined by the schema
format, e.g. percentage or bitmap.

Move this property into struct resctrl_schema and get the filesystem
parts of resctrl to set it based on the schema format. Remove
rdt_init_padding(), its work is be done by schemata_list_add(),
allowing max_name_width and max_data_width to be moved out of core.c
which has no counterpart after the move to fs.

The logic for calculating max_name_width was moved in earlier patches,
but the definition was not moved.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
Changes since v3:
 * Moved some words around in the commit message - maybe this is the right mood?
 * Added a full-stop to an existing comment.

Changes since v2:
 * This patch is new.
---
 arch/x86/kernel/cpu/resctrl/core.c     | 26 --------------------------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 11 +++++++++++
 include/linux/resctrl.h                |  4 ++--
 3 files changed, 13 insertions(+), 28 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index f16014ee48aa..cb1d634274b4 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.
@@ -224,7 +218,6 @@ static 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;
@@ -264,8 +257,6 @@ static 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;
 
@@ -285,7 +276,6 @@ 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;
@@ -781,20 +771,6 @@ 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,
@@ -1092,8 +1068,6 @@ 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/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 1ce851447923..ed06384f9161 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 and max resource data width
+ * to display the schemata in a tabular format.
+ */
+int max_name_width, max_data_width;
+
 static struct seq_buf last_cmd_status;
 static char last_cmd_status_buf[512];
 
@@ -2603,15 +2609,20 @@ 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->data_width = (r->cache.cbm_len + 3) / 4;
 		break;
 	case RESCTRL_SCHEMA_PERCENTAGE:
 		s->fmt_str = "%d=%0*u";
+		s->data_width = 3;
 		break;
 	case RESCTRL_SCHEMA_MBPS:
 		s->fmt_str = "%d=%0*u";
+		s->data_width = 4;
 		break;
 	}
 
+	max_data_width = max(max_data_width, s->data_width);
+
 	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 1624d4b15b52..fe3c1ff732de 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.
- * @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
@@ -234,7 +233,6 @@ 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;
@@ -254,6 +252,7 @@ struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l);
  * @list:	Member of resctrl_schema_all.
  * @name:	The name to use in the "schemata" file.
  * @fmt_str:	Format string to show domain value
+ * @data_width:	Character width of data when displaying
  * @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.
@@ -265,6 +264,7 @@ struct resctrl_schema {
 	struct list_head		list;
 	char				name[8];
 	const char			*fmt_str;
+	int				data_width;
 	enum resctrl_conf_type		conf_type;
 	struct rdt_resource		*res;
 	u32				num_closid;
-- 
2.39.2

[PATCH v4 07/39] 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.

Add a max_bw property for AMD platforms to specify their maximum
MBA bandwidth. This 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
---
Changes since v2:
 * This patch is new.
---
 arch/x86/kernel/cpu/resctrl/core.c        | 2 ++
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 9 +++++----
 include/linux/resctrl.h                   | 2 ++
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index cb1d634274b4..f0bbc1350070 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -208,6 +208,7 @@ static 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;
@@ -245,6 +246,7 @@ static bool __rdt_get_mem_config_amd(struct rdt_resource *r)
 	hw_res->num_closid = edx + 1;
 	r->default_ctrl = 1 << eax;
 	r->schema_fmt = RESCTRL_SCHEMA_MBPS;
+	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 1d9ad4d82bf0..4de1fea6190d 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -57,10 +57,10 @@ static bool bw_validate(char *buf, unsigned long *data, struct rdt_resource *r)
 		return false;
 	}
 
-	if ((bw < r->membw.min_bw || bw > r->default_ctrl) &&
+	if ((bw < r->membw.min_bw || bw > r->membw.max_bw) &&
 	    !is_mba_sc(r)) {
 		rdt_last_cmd_printf("MB value %ld out of range [%d,%d]\n", bw,
-				    r->membw.min_bw, r->default_ctrl);
+				    r->membw.min_bw, r->membw.max_bw);
 		return false;
 	}
 
@@ -108,8 +108,9 @@ 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) - 1;
 	unsigned int cbm_len = r->cache.cbm_len;
+	unsigned long first_bit, zero_bit, val;
 	int ret;
 
 	ret = kstrtoul(buf, 16, &val);
@@ -118,7 +119,7 @@ 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/include/linux/resctrl.h b/include/linux/resctrl.h
index fe3c1ff732de..5f08fb2f235f 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;
-- 
2.39.2

[PATCH v4 08/39] 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 by the filesystem parts
of resctrl to report to user-space.

This means the value has to be shared, but might not match the
properties of the control. e.g. a percentage greater than 100.

Instead, determine the default control value from a shared helper
resctrl_get_default_ctrl() that uses the schema properties to
determine the correct value.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
Changes since v2:
 * This patch is new.
---
 arch/x86/kernel/cpu/resctrl/core.c     | 16 +++++++---------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  6 +++---
 include/linux/resctrl.h                | 21 +++++++++++++++++++--
 3 files changed, 29 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index f0bbc1350070..1628c848bfd0 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -139,7 +139,10 @@ static inline void cache_alloc_hsw_probe(void)
 {
 	struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_L3];
 	struct rdt_resource *r  = &hw_res->r_resctrl;
-	u64 max_cbm = BIT_ULL_MASK(20) - 1, l3_cbm_0;
+	u64 max_cbm, l3_cbm_0;
+
+	r->cache.cbm_len = 20;
+	max_cbm = resctrl_get_default_ctrl(r);
 
 	if (wrmsrl_safe(MSR_IA32_L3_CBM_BASE, max_cbm))
 		return;
@@ -151,8 +154,6 @@ 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;
 	r->cache.arch_has_sparse_bitmasks = false;
@@ -207,7 +208,6 @@ static 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) {
@@ -244,7 +244,6 @@ static 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->schema_fmt = RESCTRL_SCHEMA_MBPS;
 	r->membw.max_bw = 1 << eax;
 
@@ -276,8 +275,7 @@ static void rdt_get_cache_alloc_cfg(int idx, struct rdt_resource *r)
 	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;
+	r->cache.shareable_bits = ebx & resctrl_get_default_ctrl(r);
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
 		r->cache.arch_has_sparse_bitmasks = ecx.split.noncont;
 	r->alloc_capable = true;
@@ -324,7 +322,7 @@ 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 resctrl_get_default_ctrl(r);
 }
 
 static void mba_wrmsr_intel(struct msr_param *m)
@@ -433,7 +431,7 @@ 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/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index ed06384f9161..4aba311445f7 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -969,7 +969,7 @@ 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;
 }
 
@@ -2874,7 +2874,7 @@ 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);
 	}
@@ -3409,7 +3409,7 @@ 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 5f08fb2f235f..0eb9854bf94f 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -218,7 +218,6 @@ 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
@@ -235,7 +234,6 @@ 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;
@@ -272,6 +270,25 @@ 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_PERCENTAGE:
+		return 100u;
+	case RESCTRL_SCHEMA_MBPS:
+		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);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
-- 
2.39.2

[PATCH v4 09/39] 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

---
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 12dbd2588ca7..f61382258743 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 4aba311445f7..520227455f76 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -3721,14 +3721,21 @@ 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.
@@ -3761,6 +3768,7 @@ 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 */
@@ -3771,10 +3779,10 @@ 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
-- 
2.39.2

[PATCH v4 10/39] 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

---
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 520227455f76..8d2de597bdf6 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -346,13 +346,13 @@ 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);
 	}
 
 	/*
@@ -367,11 +367,20 @@ 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 0eb9854bf94f..096621a8f69b 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -270,6 +270,28 @@ 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.
-- 
2.39.2

[PATCH v4 11/39] x86/resctrl: Export resctrl fs's init function

[James Morse]

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

x86's arch code init functions for RDT are renamed 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
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
---
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 1628c848bfd0..19852ba2c826 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -1052,7 +1052,7 @@ 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;
@@ -1075,7 +1075,7 @@ 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;
@@ -1091,18 +1091,18 @@ 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 ffcade365070..bb88be45b8c4 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -326,9 +326,6 @@ extern struct list_head rdt_all_groups;
 
 extern int max_name_width, max_data_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 00d906a1f51c..9cdca9d2bbde 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1031,7 +1031,7 @@ 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 8d2de597bdf6..adc86568f72b 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4225,14 +4225,14 @@ 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;
 
@@ -4280,7 +4280,7 @@ 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 096621a8f69b..2271fa7eb6c4 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -407,4 +407,7 @@ 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 */
-- 
2.39.2

[PATCH v4 12/39] x86/resctrl: Wrap resctrl_arch_find_domain() around rdt_find_domain()

[James Morse]

rdt_find_domain() finds a domain given a resource and a cache-id.
It's not quite right for the resctrl arch API as it also returns the
position to insert a new domain, which is needed when bringing a
domain online in the arch code.

Wrap rdt_find_domain() in another function resctrl_arch_find_domain()
in order to avoid the unnecessary argument outside the arch code.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64

---
Changes since v3:
 * Used domain_list as a meaningful name instead of 'h'.

Changes since v1:
 * [Commit message only] Minor rewording to avoid "impersonating code".

 * [Commit message only] Typo fix:
   s/in a another/in another/ in commit message.
---
 arch/x86/kernel/cpu/resctrl/core.c        | 10 ++++++++--
 arch/x86/kernel/cpu/resctrl/ctrlmondata.c |  2 +-
 arch/x86/kernel/cpu/resctrl/internal.h    |  2 --
 include/linux/resctrl.h                   |  3 +++
 4 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 19852ba2c826..4a0dbdc2da4d 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -398,8 +398,8 @@ void rdt_ctrl_update(void *arg)
  * 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)
+static 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;
@@ -420,6 +420,12 @@ struct rdt_domain_hdr *rdt_find_domain(struct list_head *h, int id,
 	return NULL;
 }
 
+struct rdt_domain_hdr *resctrl_arch_find_domain(struct list_head *domain_list,
+						int id)
+{
+	return rdt_find_domain(domain_list, id, NULL);
+}
+
 static void setup_default_ctrlval(struct rdt_resource *r, u32 *dc)
 {
 	struct rdt_hw_resource *hw_res = resctrl_to_arch_res(r);
diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
index 4de1fea6190d..4fba6e79bb06 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -622,7 +622,7 @@ 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_arch_find_domain(&r->mon_domains, domid);
 		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 bb88be45b8c4..0b2113364caa 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -578,8 +578,6 @@ 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 2271fa7eb6c4..1eb6dc5b7b79 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -313,6 +313,9 @@ static inline u32 resctrl_get_default_ctrl(struct rdt_resource *r)
 
 /* The number of closid supported by this resource regardless of CDP */
 u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
+
+struct rdt_domain_hdr *resctrl_arch_find_domain(struct list_head *domain_list,
+						int id);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
 /*
-- 
2.39.2

[PATCH v4 13/39] 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

---
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 42decde38320..dcdec2cb7b92 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19203,6 +19203,7 @@ 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 f61382258743..3b225040f617 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 0b2113364caa..d355aa676158 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 1eb6dc5b7b79..c8cd6dde91ed 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..51c51a1aabfb
--- /dev/null
+++ b/include/linux/resctrl_types.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2024 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 */
-- 
2.39.2

[PATCH v4 14/39] x86/resctrl: Add a resctrl helper to reset all the resources

[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.

Add an architecture helper to reset all resources.

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

---
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/include/asm/resctrl.h         |  2 ++
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 16 +++++++++++-----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index 3b225040f617..e7af45aaeabb 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -16,6 +16,8 @@
  */
 #define X86_RESCTRL_EMPTY_CLOSID         ((u32)~0)
 
+void resctrl_arch_reset_resources(void);
+
 /**
  * struct resctrl_pqr_state - State cache for the PQR MSR
  * @cur_rmid:		The cached Resource Monitoring ID
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index adc86568f72b..1597add37b97 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2891,6 +2891,14 @@ static int reset_all_ctrls(struct rdt_resource *r)
 	return 0;
 }
 
+void resctrl_arch_reset_resources(void)
+{
+	struct rdt_resource *r;
+
+	for_each_alloc_capable_rdt_resource(r)
+		reset_all_ctrls(r);
+}
+
 /*
  * Move tasks from one to the other group. If @from is NULL, then all tasks
  * in the systems are moved unconditionally (used for teardown).
@@ -3000,16 +3008,14 @@ static void rmdir_all_sub(void)
 
 static void rdt_kill_sb(struct super_block *sb)
 {
-	struct rdt_resource *r;
-
 	cpus_read_lock();
 	mutex_lock(&rdtgroup_mutex);
 
 	rdt_disable_ctx();
 
-	/*Put everything back to default values. */
-	for_each_alloc_capable_rdt_resource(r)
-		reset_all_ctrls(r);
+	/* Put everything back to default values. */
+	resctrl_arch_reset_resources();
+
 	rmdir_all_sub();
 	rdt_pseudo_lock_release();
 	rdtgroup_default.mode = RDT_MODE_SHAREABLE;
-- 
2.39.2

[PATCH v4 15/39] 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
---
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 4a0dbdc2da4d..9d4d64b4e357 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -1101,14 +1101,9 @@ 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 d355aa676158..3fdeca6e3d21 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -579,7 +579,7 @@ 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 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 9cdca9d2bbde..afbda09aacf5 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1044,10 +1044,13 @@ static int dom_data_init(struct rdt_resource *r)
 	return err;
 }
 
-static void __exit dom_data_exit(void)
+static void 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;
@@ -1056,6 +1059,7 @@ static void __exit dom_data_exit(void)
 	kfree(rmid_ptrs);
 	rmid_ptrs = NULL;
 
+out_unlock:
 	mutex_unlock(&rdtgroup_mutex);
 }
 
@@ -1238,9 +1242,11 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 	return 0;
 }
 
-void __exit rdt_put_mon_l3_config(void)
+void 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 1597add37b97..576f6b183980 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4291,4 +4291,6 @@ 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();
 }
-- 
2.39.2

[PATCH v4 16/39] 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
---
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 |  1 +
 arch/x86/kernel/cpu/resctrl/monitor.c  | 36 +++++++++++++++++++++-----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 22 +++++++++++++++-
 3 files changed, 51 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 3fdeca6e3d21..8e52e81a044b 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -586,6 +586,7 @@ 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 afbda09aacf5..cecc96213c49 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1179,12 +1179,40 @@ 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();
 
@@ -1214,10 +1242,6 @@ 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;
 
@@ -1235,8 +1259,6 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
 		}
 	}
 
-	l3_mon_evt_init(r);
-
 	r->mon_capable = true;
 
 	return 0;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 576f6b183980..f53d6ce390ac 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4097,6 +4097,19 @@ 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();
@@ -4247,9 +4260,15 @@ 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)
@@ -4282,6 +4301,7 @@ int __init resctrl_init(void)
 
 cleanup_mountpoint:
 	sysfs_remove_mount_point(fs_kobj, "resctrl");
+	resctrl_mon_resource_exit();
 
 	return ret;
 }
-- 
2.39.2

[PATCH v4 17/39] 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 the core header so existing x86 arch code continues
to use them.

Signed-off-by: James Morse <james.morse@arm.com>
---
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 8e52e81a044b..84e0d019423d 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -472,14 +472,6 @@ extern struct rdt_hw_resource rdt_resources_all[];
 extern struct rdtgroup rdtgroup_default;
 extern struct dentry *debugfs_resctrl;
 
-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;
@@ -489,27 +481,6 @@ 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 c8cd6dde91ed..04a410a5e739 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)->rid < RDT_NUM_RESOURCES - 1;					\
+	     (_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.
-- 
2.39.2

[PATCH v4 18/39] x86/resctrl: Export the is_mbm_*_enabled() helpers to asm/resctrl.h

[James Morse]

The architecture specific parts of resctrl have helpers to hide accesses
to the rdt_mon_features bitmap.

Once the filesystem parts of resctrl are moved, these can no longer live
in internal.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
---
 arch/x86/include/asm/resctrl.h         | 16 +++++++++++
 arch/x86/kernel/cpu/resctrl/core.c     |  4 +--
 arch/x86/kernel/cpu/resctrl/internal.h | 27 -----------------
 arch/x86/kernel/cpu/resctrl/monitor.c  | 18 ++++++------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 40 +++++++++++++++++---------
 5 files changed, 53 insertions(+), 52 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index e7af45aaeabb..c69241447cc2 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -44,6 +44,7 @@ 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);
@@ -83,6 +84,21 @@ 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 9d4d64b4e357..e961401bb5a1 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -485,13 +485,13 @@ 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) {
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 84e0d019423d..b705a7bd4128 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;
 
@@ -404,32 +403,6 @@ 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 cecc96213c49..68e05bd0eb94 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);
@@ -757,7 +757,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_mon_domain *dom_mbm)
 	struct list_head *head;
 	struct rdtgroup *entry;
 
-	if (!is_mbm_local_enabled())
+	if (!resctrl_arch_is_mbm_local_enabled())
 		return;
 
 	r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
@@ -825,7 +825,7 @@ 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 we hold the global mutex.
 	 */
-	if (is_mbm_total_enabled()) {
+	if (resctrl_arch_is_mbm_total_enabled()) {
 		rr.evtid = QOS_L3_MBM_TOTAL_EVENT_ID;
 		rr.val = 0;
 		rr.arch_mon_ctx = resctrl_arch_mon_ctx_alloc(rr.r, rr.evtid);
@@ -839,7 +839,7 @@ static void mbm_update(struct rdt_resource *r, struct rdt_mon_domain *d,
 
 		resctrl_arch_mon_ctx_free(rr.r, rr.evtid, rr.arch_mon_ctx);
 	}
-	if (is_mbm_local_enabled()) {
+	if (resctrl_arch_is_mbm_local_enabled()) {
 		rr.evtid = QOS_L3_MBM_LOCAL_EVENT_ID;
 		rr.val = 0;
 		rr.arch_mon_ctx = resctrl_arch_mon_ctx_alloc(rr.r, rr.evtid);
@@ -1089,11 +1089,11 @@ 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 f53d6ce390ac..52e0fe261ceb 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -108,6 +108,18 @@ 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.
@@ -155,7 +167,7 @@ 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;
@@ -2373,7 +2385,7 @@ 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_local_enabled() &&
+	return (resctrl_arch_is_mbm_local_enabled() &&
 		r->alloc_capable && is_mba_linear() &&
 		r->ctrl_scope == rmbm->mon_scope);
 }
@@ -2748,7 +2760,7 @@ 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,
@@ -3122,7 +3134,7 @@ 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);
 	}
 
@@ -4077,9 +4089,9 @@ 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
@@ -4115,12 +4127,12 @@ 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) {
@@ -4128,7 +4140,7 @@ 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) {
@@ -4167,13 +4179,13 @@ 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);
 
 	/*
@@ -4228,12 +4240,12 @@ 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);
 		}
-- 
2.39.2

[PATCH v4 19/39] 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 mbm_config_rftype_init() to create
the files that allow the configuration.

Splitting this into separate architecture and filesystem parts would
require the struct mon_evt and mbm_config_rftype_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
mbm_config_rftype_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.

resctrl_arch_is_evt_configurable() uses rdt_cpu_has() from
resctrl_mon_resource_init(), which isn't marked __init. In addition,
MPAM needs to initialise resctrl late. Drop the __init on the relevant
functions.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 arch/x86/kernel/cpu/resctrl/core.c     | 19 +++++++++++++++++--
 arch/x86/kernel/cpu/resctrl/internal.h |  4 ++--
 arch/x86/kernel/cpu/resctrl/monitor.c  | 18 +++++++++---------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  2 +-
 include/linux/resctrl.h                |  2 ++
 5 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index e961401bb5a1..bfdd49695c37 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -802,7 +802,7 @@ struct rdt_options {
 	bool	force_off, force_on;
 };
 
-static struct rdt_options rdt_options[]  __initdata = {
+static struct rdt_options rdt_options[]  __ro_after_init = {
 	RDT_OPT(RDT_FLAG_CMT,	    "cmt",	X86_FEATURE_CQM_OCCUP_LLC),
 	RDT_OPT(RDT_FLAG_MBM_TOTAL, "mbmtotal", X86_FEATURE_CQM_MBM_TOTAL),
 	RDT_OPT(RDT_FLAG_MBM_LOCAL, "mbmlocal", X86_FEATURE_CQM_MBM_LOCAL),
@@ -842,7 +842,7 @@ static int __init set_rdt_options(char *str)
 }
 __setup("rdt", set_rdt_options);
 
-bool __init rdt_cpu_has(int flag)
+bool rdt_cpu_has(int flag)
 {
 	bool ret = boot_cpu_has(flag);
 	struct rdt_options *o;
@@ -862,6 +862,21 @@ bool __init rdt_cpu_has(int flag)
 	return ret;
 }
 
+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/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index b705a7bd4128..72c8fc2a5d44 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -524,7 +524,7 @@ int alloc_rmid(u32 closid);
 void free_rmid(u32 closid, u32 rmid);
 int rdt_get_mon_l3_config(struct rdt_resource *r);
 void resctrl_mon_resource_exit(void);
-bool __init rdt_cpu_has(int flag);
+bool 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,
@@ -544,7 +544,7 @@ bool has_busy_rmid(struct rdt_mon_domain *d);
 void __check_limbo(struct rdt_mon_domain *d, bool force_free);
 void rdt_domain_reconfigure_cdp(struct rdt_resource *r);
 void __init thread_throttle_mode_init(void);
-void __init mbm_config_rftype_init(const char *config);
+void mbm_config_rftype_init(const char *config);
 void rdt_staged_configs_clear(void);
 bool closid_allocated(unsigned int closid);
 int resctrl_find_cleanest_closid(void);
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 68e05bd0eb94..ae8552ef98e6 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1205,6 +1205,15 @@ 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;
+		mbm_config_rftype_init("mbm_total_bytes_config");
+	}
+	if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_LOCAL_EVENT_ID)) {
+		mbm_local_event.configurable = true;
+		mbm_config_rftype_init("mbm_local_bytes_config");
+	}
+
 	return 0;
 }
 
@@ -1248,15 +1257,6 @@ 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;
-			mbm_config_rftype_init("mbm_total_bytes_config");
-		}
-		if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {
-			mbm_local_event.configurable = true;
-			mbm_config_rftype_init("mbm_local_bytes_config");
-		}
 	}
 
 	r->mon_capable = true;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 52e0fe261ceb..a2e6914db31c 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2059,7 +2059,7 @@ void __init thread_throttle_mode_init(void)
 	rft->fflags = RFTYPE_CTRL_INFO | RFTYPE_RES_MB;
 }
 
-void __init mbm_config_rftype_init(const char *config)
+void mbm_config_rftype_init(const char *config)
 {
 	struct rftype *rft;
 
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 04a410a5e739..c98ce37426a6 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -317,6 +317,8 @@ struct rdt_domain_hdr *resctrl_arch_find_domain(struct list_head *domain_list,
 						int id);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
+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.
-- 
2.39.2

[PATCH v4 20/39] 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
---
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 | 34 +++++++++++++-------------
 include/linux/resctrl.h                | 25 +++++++++++++++++++
 2 files changed, 42 insertions(+), 17 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index a2e6914db31c..26905d76dec1 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1571,11 +1571,6 @@ 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
 
 /**
@@ -1600,9 +1595,9 @@ 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 *info)
 {
-	struct mon_config_info *mon_info = info;
+	struct resctrl_mon_config_info *mon_info = info;
 	unsigned int index;
 	u64 msrval;
 
@@ -1617,14 +1612,15 @@ static void mon_event_config_read(void *info)
 	mon_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 = {0};
+	struct resctrl_mon_config_info mon_info = {0};
 	struct rdt_mon_domain *dom;
 	bool sep = false;
 
@@ -1635,9 +1631,11 @@ 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;
@@ -1670,9 +1668,9 @@ 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 *info)
 {
-	struct mon_config_info *mon_info = info;
+	struct resctrl_mon_config_info *mon_info = info;
 	unsigned int index;
 
 	index = mon_event_config_index_get(mon_info->evtid);
@@ -1686,14 +1684,16 @@ static void mon_event_config_write(void *info)
 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;
 
@@ -1705,7 +1705,7 @@ 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 c98ce37426a6..ab7d6f5e99a8 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -274,6 +274,13 @@ 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.
@@ -319,6 +326,24 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
 bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt);
 
+/**
+ * resctrl_arch_mon_event_config_write() - Write the config for a counter.
+ * @info:	struct resctrl_mon_config_info describing the resource, domain
+ *		and event.
+ *
+ * Must be called on a CPU that is a member of the specified domain.
+ */
+void resctrl_arch_mon_event_config_write(void *info);
+
+/**
+ * resctrl_arch_mon_event_config_read() - Read the config for a counter.
+ * @info:	struct resctrl_mon_config_info describing the resource, domain
+ *		and event.
+ *
+ * Must be called on a CPU that is a member of the specified domain.
+ */
+void resctrl_arch_mon_event_config_read(void *info);
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.
-- 
2.39.2

[PATCH v4 21/39] 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
---
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 72c8fc2a5d44..87cf2d854205 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -415,8 +415,6 @@ 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
@@ -430,7 +428,6 @@ 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 ae8552ef98e6..175fd7dbf34f 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1256,7 +1256,7 @@ 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 26905d76dec1..714cc54006e6 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1722,7 +1722,6 @@ 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;
@@ -1749,9 +1748,9 @@ 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 ab7d6f5e99a8..ef82420ef385 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -219,6 +219,8 @@ 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 Event Configuration (BMEC) is supported.
  * @cdp_capable:	Is the CDP feature available on this resource
  */
 struct rdt_resource {
@@ -235,6 +237,7 @@ struct rdt_resource {
 	char			*name;
 	enum resctrl_schema_fmt	schema_fmt;
 	struct list_head	evt_list;
+	unsigned int		mbm_cfg_mask;
 	bool			cdp_capable;
 };
 
-- 
2.39.2

[PATCH v4 22/39] 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. pseudo_lock_fn()
is not at all portable. Label these 'resctrl_arch_' so they stay
under /arch/x86.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 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 c69241447cc2..a0b911f4f193 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -211,6 +211,11 @@ 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 e69489d48625..459fabd054a0 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};
@@ -1205,18 +1207,18 @@ static int pseudo_lock_measure_cycles(struct rdtgroup *rdtgrp, int sel)
 	plr->cpu = cpu;
 
 	if (sel == 1)
-		thread = kthread_create_on_node(measure_cycles_lat_fn, plr,
-						cpu_to_node(cpu),
+		thread = kthread_create_on_node(resctrl_arch_measure_cycles_lat_fn,
+						plr, cpu_to_node(cpu),
 						"pseudo_lock_measure/%u",
 						cpu);
 	else if (sel == 2)
-		thread = kthread_create_on_node(measure_l2_residency, plr,
-						cpu_to_node(cpu),
+		thread = kthread_create_on_node(resctrl_arch_measure_l2_residency,
+						plr, cpu_to_node(cpu),
 						"pseudo_lock_measure/%u",
 						cpu);
 	else if (sel == 3)
-		thread = kthread_create_on_node(measure_l3_residency, plr,
-						cpu_to_node(cpu),
+		thread = kthread_create_on_node(resctrl_arch_measure_l3_residency,
+						plr, cpu_to_node(cpu),
 						"pseudo_lock_measure/%u",
 						cpu);
 	else
@@ -1315,7 +1317,7 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 
 	plr->thread_done = 0;
 
-	thread = kthread_create_on_node(pseudo_lock_fn, rdtgrp,
+	thread = kthread_create_on_node(resctrl_arch_pseudo_lock_fn, rdtgrp,
 					cpu_to_node(plr->cpu),
 					"pseudo_lock/%u", plr->cpu);
 	if (IS_ERR(thread)) {
-- 
2.39.2

[PATCH v4 23/39] 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 file.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
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 | 48 +++++++++++++++++++++-----
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  3 +-
 4 files changed, 52 insertions(+), 11 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 007bab9f2a0e..7e908186dc32 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -493,6 +493,7 @@ 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.
 
@@ -509,6 +510,12 @@ 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 87cf2d854205..9e5b174bb5ba 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -505,14 +505,6 @@ 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);
@@ -546,4 +538,44 @@ 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 714cc54006e6..68947e0f69d9 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1444,7 +1444,8 @@ 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;
-- 
2.39.2

[PATCH v4 24/39] 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.

Instead of exporting this value, make
resctrl_arch_get_prefetch_disable_bits() set it so that the other
arch-code helpers can use the cached-value.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 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 459fabd054a0..cd0fdb7408d4 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;
 	}
-- 
2.39.2

[PATCH v4 25/39] 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
---
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 | 13 ++++----
 include/linux/resctrl.h                   | 39 +++++++++++++++++++++++
 4 files changed, 47 insertions(+), 44 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index a0b911f4f193..faec906ee7fe 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -212,7 +212,7 @@ 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 9e5b174bb5ba..a0e11260235f 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 cd0fdb7408d4..f671c5dea079 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.
@@ -1320,7 +1320,8 @@ int rdtgroup_pseudo_lock_create(struct rdtgroup *rdtgrp)
 
 	plr->thread_done = 0;
 
-	thread = kthread_create_on_node(resctrl_arch_pseudo_lock_fn, rdtgrp,
+	plr->closid = rdtgrp->closid;
+	thread = kthread_create_on_node(resctrl_arch_pseudo_lock_fn, plr,
 					cpu_to_node(plr->cpu),
 					"pseudo_lock/%u", plr->cpu);
 	if (IS_ERR(thread)) {
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index ef82420ef385..f09c07e598f7 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
-- 
2.39.2

[PATCH v4 26/39] x86/resctrl: Move thread_throttle_mode_init() to be managed by resctrl

[James Morse]

thread_throttle_mode_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 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.

Call thread_throttle_mode_init() from resctrl_setup(), check the
membw.throttle_mode on the MBA resource. This avoids publishing an
extra function between the architecture and filesystem code.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 arch/x86/kernel/cpu/resctrl/core.c     | 1 -
 arch/x86/kernel/cpu/resctrl/internal.h | 1 -
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 9 ++++++++-
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index bfdd49695c37..b36d8e8afc1a 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -224,7 +224,6 @@ static bool __get_mem_config_intel(struct rdt_resource *r)
 		r->membw.throttle_mode = THREAD_THROTTLE_PER_THREAD;
 	else
 		r->membw.throttle_mode = THREAD_THROTTLE_MAX;
-	thread_throttle_mode_init();
 
 	r->alloc_capable = true;
 
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index a0e11260235f..66ff26a121ed 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -495,7 +495,6 @@ void cqm_handle_limbo(struct work_struct *work);
 bool has_busy_rmid(struct rdt_mon_domain *d);
 void __check_limbo(struct rdt_mon_domain *d, bool force_free);
 void rdt_domain_reconfigure_cdp(struct rdt_resource *r);
-void __init thread_throttle_mode_init(void);
 void mbm_config_rftype_init(const char *config);
 void rdt_staged_configs_clear(void);
 bool closid_allocated(unsigned int closid);
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 68947e0f69d9..b35f9659e536 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2048,10 +2048,15 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
 	return NULL;
 }
 
-void __init thread_throttle_mode_init(void)
+static void __init thread_throttle_mode_init(void)
 {
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 	struct rftype *rft;
 
+	if (!r->alloc_capable ||
+	    r->membw.throttle_mode == THREAD_THROTTLE_UNDEFINED)
+		return;
+
 	rft = rdtgroup_get_rftype_by_name("thread_throttle_mode");
 	if (!rft)
 		return;
@@ -4272,6 +4277,8 @@ int __init resctrl_init(void)
 
 	rdtgroup_setup_default();
 
+	thread_throttle_mode_init();
+
 	ret = resctrl_mon_resource_init();
 	if (ret)
 		return ret;
-- 
2.39.2

[PATCH v4 27/39] 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.

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
---
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 4fba6e79bb06..3c9ac1c853eb 100644
--- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
+++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c
@@ -283,25 +283,12 @@ 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))
@@ -338,7 +325,7 @@ 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;
@@ -458,7 +445,7 @@ 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 f09c07e598f7..f99bd2996cba 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -386,6 +386,21 @@ void resctrl_arch_mon_event_config_write(void *info);
  */
 void resctrl_arch_mon_event_config_read(void *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.
-- 
2.39.2

[PATCH v4 28/39] x86/resctrl: Claim get_{mon,ctrl}_domain_from_cpu() helpers for resctrl

[James Morse]

get_{mon,ctrl}_domain_from_cpu() are handy helpers that both the arch
code and resctrl need to use. Rename them to have a resctrl_ prefix
and move them to a header file.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 arch/x86/kernel/cpu/resctrl/core.c     | 30 ---------------------
 arch/x86/kernel/cpu/resctrl/internal.h |  2 --
 arch/x86/kernel/cpu/resctrl/monitor.c  |  2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c |  2 +-
 include/linux/resctrl.h                | 37 ++++++++++++++++++++++++++
 5 files changed, 39 insertions(+), 34 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index b36d8e8afc1a..1e2ea470ea45 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -345,36 +345,6 @@ 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 66ff26a121ed..f5801048404d 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -468,8 +468,6 @@ 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 175fd7dbf34f..39c450624ed0 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -767,7 +767,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_mon_domain *dom_mbm)
 	idx = resctrl_arch_rmid_idx_encode(closid, rmid);
 	pmbm_data = &dom_mbm->mbm_local[idx];
 
-	dom_mba = get_ctrl_domain_from_cpu(smp_processor_id(), r_mba);
+	dom_mba = resctrl_get_ctrl_domain_from_cpu(smp_processor_id(), r_mba);
 	if (!dom_mba) {
 		pr_warn_once("Failure to get domain for MBA update\n");
 		return;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index b35f9659e536..db2d3c7036b2 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4243,7 +4243,7 @@ void resctrl_offline_cpu(unsigned int cpu)
 	if (!l3->mon_capable)
 		goto out_unlock;
 
-	d = get_mon_domain_from_cpu(cpu, l3);
+	d = resctrl_get_mon_domain_from_cpu(cpu, l3);
 	if (d) {
 		if (resctrl_is_mbm_enabled() && cpu == d->mbm_work_cpu) {
 			cancel_delayed_work(&d->mbm_over);
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index f99bd2996cba..31a28151193d 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -3,6 +3,7 @@
 #define _RESCTRL_H
 
 #include <linux/cacheinfo.h>
+#include <linux/cpu.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
 #include <linux/pid.h>
@@ -401,6 +402,42 @@ static inline u32 resctrl_get_config_index(u32 closid,
 	}
 }
 
+/*
+ * Caller must hold the cpuhp read lock to prevent the struct rdt_domain being
+ * freed.
+ */
+static inline struct rdt_ctrl_domain *
+resctrl_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;
+}
+
+static inline struct rdt_mon_domain *
+resctrl_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;
+}
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.
-- 
2.39.2

[PATCH v4 29/39] x86/resctrl: Describe resctrl's bitmap size assumptions

[James Morse]

resctrl operates on configuration bitmaps and a bitmap of allocated
CLOSID, both are stored in a u32.

MPAM supports configuration/portion bitmaps and PARTIDs larger
than will fit in a u32.

Add some preprocessor values that make it clear why MPAM clamps
some of these values. This will make it easier to find code related
to these values if this resctrl behaviour ever changes.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 include/linux/resctrl.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 31a28151193d..1ebf705ec3c5 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -27,6 +27,17 @@ int proc_resctrl_show(struct seq_file *m,
 /* max value for struct rdt_domain's mbps_val */
 #define MBA_MAX_MBPS   U32_MAX
 
+/*
+ * Resctrl uses a u32 as a closid bitmap. The maximum closid is 32.
+ */
+#define RESCTRL_MAX_CLOSID		32
+
+/*
+ * Resctrl uses u32 to hold the user-space config. The maximum bitmap size is
+ * 32.
+ */
+#define RESCTRL_MAX_CBM			32
+
 /* Walk all possible resources, with variants for only controls or monitors. */
 #define for_each_rdt_resource(_r)						\
 	for ((_r) = resctrl_arch_get_resource(0);				\
-- 
2.39.2

[PATCH v4 30/39] x86/resctrl: Rename resctrl_sched_in() to begin with "resctrl_arch_"

[James Morse]

resctrl_sched_in() loads the architecture specific CPU MSRs with the
CLOSID and RMID values. This function was named before resctrl was
split to have architecture specific code, and generic filesystem code.

This function is obviously architecture specific, but does not begin
with 'resctrl_arch_', making it the odd one out in the functions an
architecture needs to support to enable resctrl.

Rename it for consistency. This is purely cosmetic.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 arch/x86/include/asm/resctrl.h         |  4 ++--
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 12 ++++++------
 arch/x86/kernel/process_32.c           |  2 +-
 arch/x86/kernel/process_64.c           |  2 +-
 4 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index faec906ee7fe..a8bc1d68f889 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -177,7 +177,7 @@ static inline bool resctrl_arch_match_rmid(struct task_struct *tsk, u32 ignored,
 	return READ_ONCE(tsk->rmid) == rmid;
 }
 
-static inline void resctrl_sched_in(struct task_struct *tsk)
+static inline void resctrl_arch_sched_in(struct task_struct *tsk)
 {
 	if (static_branch_likely(&rdt_enable_key))
 		__resctrl_sched_in(tsk);
@@ -220,7 +220,7 @@ void resctrl_cpu_detect(struct cpuinfo_x86 *c);
 
 #else
 
-static inline void resctrl_sched_in(struct task_struct *tsk) {}
+static inline void resctrl_arch_sched_in(struct task_struct *tsk) {}
 static inline void resctrl_cpu_detect(struct cpuinfo_x86 *c) {}
 
 #endif /* CONFIG_X86_CPU_RESCTRL */
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index db2d3c7036b2..8610a7e01f52 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -353,7 +353,7 @@ static int rdtgroup_cpus_show(struct kernfs_open_file *of,
 }
 
 /*
- * This is safe against resctrl_sched_in() called from __switch_to()
+ * This is safe against resctrl_arch_sched_in() called from __switch_to()
  * because __switch_to() is executed with interrupts disabled. A local call
  * from update_closid_rmid() is protected against __switch_to() because
  * preemption is disabled.
@@ -372,7 +372,7 @@ void resctrl_arch_sync_cpu_closid_rmid(void *info)
 	 * executing task might have its own closid selected. Just reuse
 	 * the context switch code.
 	 */
-	resctrl_sched_in(current);
+	resctrl_arch_sched_in(current);
 }
 
 /*
@@ -597,7 +597,7 @@ static void _update_task_closid_rmid(void *task)
 	 * Otherwise, the MSR is updated when the task is scheduled in.
 	 */
 	if (task == current)
-		resctrl_sched_in(task);
+		resctrl_arch_sched_in(task);
 }
 
 static void update_task_closid_rmid(struct task_struct *t)
@@ -655,7 +655,7 @@ static int __rdtgroup_move_task(struct task_struct *tsk,
 	 * Ensure the task's closid and rmid are written before determining if
 	 * the task is current that will decide if it will be interrupted.
 	 * This pairs with the full barrier between the rq->curr update and
-	 * resctrl_sched_in() during context switch.
+	 * resctrl_arch_sched_in() during context switch.
 	 */
 	smp_mb();
 
@@ -2939,8 +2939,8 @@ static void rdt_move_group_tasks(struct rdtgroup *from, struct rdtgroup *to,
 			/*
 			 * Order the closid/rmid stores above before the loads
 			 * in task_curr(). This pairs with the full barrier
-			 * between the rq->curr update and resctrl_sched_in()
-			 * during context switch.
+			 * between the rq->curr update and
+			 * resctrl_arch_sched_in() during context switch.
 			 */
 			smp_mb();
 
diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 0917c7f25720..8697b02dabf1 100644
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -211,7 +211,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	switch_fpu_finish(next_p);
 
 	/* Load the Intel cache allocation PQR MSR. */
-	resctrl_sched_in(next_p);
+	resctrl_arch_sched_in(next_p);
 
 	return prev_p;
 }
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 6d3d20e3e43a..162b11b824ee 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -707,7 +707,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	}
 
 	/* Load the Intel cache allocation PQR MSR. */
-	resctrl_sched_in(next_p);
+	resctrl_arch_sched_in(next_p);
 
 	return prev_p;
 }
-- 
2.39.2

[PATCH v4 31/39] x86/resctrl: resctrl_exit() teardown resctrl but leave the mount point

[James Morse]

resctrl_exit() was intended for use when the 'resctrl' module was unloaded.
resctrl can't be built as a module, and the kernfs helpers are not exported
so this is unlikely to change. MPAM has an error interrupt which indicates
the MPAM driver has gone haywire. Should this occur tasks could run with
the wrong control values, leading to bad performance for important tasks.
The MPAM driver needs a way to tell resctrl that no further configuration
should be attempted.

Using resctrl_exit() for this leaves the system in a funny state as
resctrl is still mounted, but cannot be un-mounted because the sysfs
directory that is typically used has been removed. Dave Martin suggests
this may cause systemd trouble in the future as not all filesystems
can be unmounted.

Add calls to remove all the files and directories in resctrl, and
remove the sysfs_remove_mount_point() call that leaves the system
in a funny state. When triggered, this causes all the resctrl files
to disappear. resctrl can be unmounted, but not mounted again.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 8610a7e01f52..19f852bbc8b0 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -4327,9 +4327,9 @@ int __init resctrl_init(void)
 
 void __exit resctrl_exit(void)
 {
+	rdtgroup_destroy_root();
 	debugfs_remove_recursive(debugfs_resctrl);
 	unregister_filesystem(&rdt_fs_type);
-	sysfs_remove_mount_point(fs_kobj, "resctrl");
 
 	resctrl_mon_resource_exit();
 }
-- 
2.39.2

[PATCH v4 32/39] x86/resctrl: Drop __init/__exit on assorted symbols

[James Morse]

Because ARM's MPAM controls are probed using MMIO, resctrl can't be
initialised until enough CPUs are online to have determined the
system-wide supported num_closid. Arm64 also supports 'late onlined
secondaries', where only a subset of CPUs are online during boot.

These two combine to mean the MPAM driver may not be able to initialise
resctrl until user-space has brought 'enough' CPUs online.

To allow MPAM to initialise resctrl after __init text has been free'd,
remove all the __init markings from resctrl.

The existing __exit markings cause these functions to be removed by the
linker as it has never been possible to build resctrl as a module. MPAM
has an error interrupt which causes the driver to reset and disable
itself. Remove the __exit markings to allow the MPAM driver to tear down
resctrl when an error occurs.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 arch/x86/kernel/cpu/resctrl/internal.h | 2 +-
 arch/x86/kernel/cpu/resctrl/monitor.c  | 2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 8 ++++----
 include/linux/resctrl.h                | 4 ++--
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index f5801048404d..c8086095954b 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -480,7 +480,7 @@ 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);
+int 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 39c450624ed0..1fd47f8a0e18 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1191,7 +1191,7 @@ static __init int snc_get_config(void)
  *
  * Returns 0 for success, or -ENOMEM.
  */
-int __init resctrl_mon_resource_init(void)
+int resctrl_mon_resource_init(void)
 {
 	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
 	int ret;
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 19f852bbc8b0..db5c18caa40e 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2048,7 +2048,7 @@ static struct rftype *rdtgroup_get_rftype_by_name(const char *name)
 	return NULL;
 }
 
-static void __init thread_throttle_mode_init(void)
+static void thread_throttle_mode_init(void)
 {
 	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
 	struct rftype *rft;
@@ -4052,7 +4052,7 @@ static void rdtgroup_destroy_root(void)
 	rdtgroup_default.kn = NULL;
 }
 
-static void __init rdtgroup_setup_default(void)
+static void rdtgroup_setup_default(void)
 {
 	mutex_lock(&rdtgroup_mutex);
 
@@ -4268,7 +4268,7 @@ void resctrl_offline_cpu(unsigned int cpu)
  *
  * Return: 0 on success or -errno
  */
-int __init resctrl_init(void)
+int resctrl_init(void)
 {
 	int ret = 0;
 
@@ -4325,7 +4325,7 @@ int __init resctrl_init(void)
 	return ret;
 }
 
-void __exit resctrl_exit(void)
+void resctrl_exit(void)
 {
 	rdtgroup_destroy_root();
 	debugfs_remove_recursive(debugfs_resctrl);
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index 1ebf705ec3c5..c97ae81a57af 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -541,7 +541,7 @@ 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);
+int resctrl_init(void);
+void resctrl_exit(void);
 
 #endif /* _RESCTRL_H */
-- 
2.39.2

[PATCH v4 33/39] x86/resctrl: Move is_mba_sc() out of core.c

[James Morse]

is_mba_sc() is defined in core.c, but has no callers there. It does
not access any architecture private structures.

Move this to rdtgroup.c where the majority of callers are. This makes
the move of the filesystem code to /fs/ cleaner.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
Changes since v2:
 * This patch is new.
---
 arch/x86/kernel/cpu/resctrl/core.c     | 15 ---------------
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 15 +++++++++++++++
 2 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 1e2ea470ea45..568127177a98 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -162,21 +162,6 @@ static inline void cache_alloc_hsw_probe(void)
 	rdt_alloc_capable = true;
 }
 
-bool is_mba_sc(struct rdt_resource *r)
-{
-	if (!r)
-		r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
-
-	/*
-	 * The software controller support is only applicable to MBA resource.
-	 * Make sure to check for resource type.
-	 */
-	if (r->rid != RDT_RESOURCE_MBA)
-		return false;
-
-	return r->membw.mba_sc;
-}
-
 /*
  * rdt_get_mb_table() - get a mapping of bandwidth(b/w) percentage values
  * exposed to user interface and the h/w understandable delay values.
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index db5c18caa40e..f5065414ca6a 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -1493,6 +1493,21 @@ unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r,
 	return size;
 }
 
+bool is_mba_sc(struct rdt_resource *r)
+{
+	if (!r)
+		r = resctrl_arch_get_resource(RDT_RESOURCE_MBA);
+
+	/*
+	 * The software controller support is only applicable to MBA resource.
+	 * Make sure to check for resource type.
+	 */
+	if (r->rid != RDT_RESOURCE_MBA)
+		return false;
+
+	return r->membw.mba_sc;
+}
+
 /*
  * rdtgroup_size_show - Display size in bytes of allocated regions
  *
-- 
2.39.2

[PATCH v4 34/39] x86/resctrl: Add end-marker to the resctrl_event_id enum

[James Morse]

The resctrl_event_id enum gives names to the counter event numbers on x86.
These are used directly by resctrl.

To allow the MPAM driver to keep an array of these the size of the enum
needs to be known.

Add a 'num_events' define which can be used to size an array. This isn't
a member of the enum to avoid updating switch statements that would
otherwise be missing a case.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 include/linux/resctrl_types.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/include/linux/resctrl_types.h b/include/linux/resctrl_types.h
index 51c51a1aabfb..70226f5ab3e3 100644
--- a/include/linux/resctrl_types.h
+++ b/include/linux/resctrl_types.h
@@ -51,4 +51,6 @@ enum resctrl_event_id {
 	QOS_L3_MBM_LOCAL_EVENT_ID	= 0x03,
 };
 
+#define QOS_NUM_EVENTS		(QOS_L3_MBM_LOCAL_EVENT_ID + 1)
+
 #endif /* __LINUX_RESCTRL_TYPES_H */
-- 
2.39.2

[PATCH v4 35/39] x86/resctrl: Remove a newline to avoid confusing the code move script

[James Morse]

The resctrl filesystem code will shortly be moved to /fs/. This involves
splitting all the existing files, with some functions remaining under
arch/x86, and others moving to fs/resctrl.

To make this reproducible, a python script does the heavy lif^W
copy-and-paste. This involves some clunky parsing of C code.

The parser gets confused by the newline after this #ifdef.
Just remove it.

Signed-off-by: James Morse <james.morse@arm.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
---
 arch/x86/kernel/cpu/resctrl/rdtgroup.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index f5065414ca6a..a7e1a445559f 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -874,7 +874,6 @@ static int rdtgroup_rmid_show(struct kernfs_open_file *of,
 }
 
 #ifdef CONFIG_PROC_CPU_RESCTRL
-
 /*
  * A task can only be part of one resctrl control group and of one monitor
  * group which is associated to that control group.
-- 
2.39.2

[PATCH v4 36/39] x86/resctrl: Split trace.h

[James Morse]

trace.h contains all the tracepoints. After the move to /fs/resctrl, some
of these will be left behind. All the pseudo_lock tracepoints remain part
of the architecture. The lone tracepoint in monitor.c moves to /fs/resctrl.

Split trace.h so that each C file includes a different trace header file.
This means the trace header files are not modified when they are moved.

Signed-off-by: James Morse <james.morse@arm.com>
---
 arch/x86/kernel/cpu/resctrl/Makefile          |  3 ++
 arch/x86/kernel/cpu/resctrl/monitor.c         |  4 ++-
 arch/x86/kernel/cpu/resctrl/monitor_trace.h   | 31 +++++++++++++++++++
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c     |  2 +-
 .../resctrl/{trace.h => pseudo_lock_trace.h}  | 24 +++-----------
 5 files changed, 42 insertions(+), 22 deletions(-)
 create mode 100644 arch/x86/kernel/cpu/resctrl/monitor_trace.h
 rename arch/x86/kernel/cpu/resctrl/{trace.h => pseudo_lock_trace.h} (56%)

diff --git a/arch/x86/kernel/cpu/resctrl/Makefile b/arch/x86/kernel/cpu/resctrl/Makefile
index 0c13b0befd8a..909be78ec6da 100644
--- a/arch/x86/kernel/cpu/resctrl/Makefile
+++ b/arch/x86/kernel/cpu/resctrl/Makefile
@@ -2,4 +2,7 @@
 obj-$(CONFIG_X86_CPU_RESCTRL)		+= core.o rdtgroup.o monitor.o
 obj-$(CONFIG_X86_CPU_RESCTRL)		+= ctrlmondata.o
 obj-$(CONFIG_RESCTRL_FS_PSEUDO_LOCK)	+= pseudo_lock.o
+
+# To allow define_trace.h's recursive include:
 CFLAGS_pseudo_lock.o = -I$(src)
+CFLAGS_monitor.o = -I$(src)
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 1fd47f8a0e18..b7662782ea59 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -26,7 +26,9 @@
 #include <asm/resctrl.h>
 
 #include "internal.h"
-#include "trace.h"
+
+#define CREATE_TRACE_POINTS
+#include "monitor_trace.h"
 
 /**
  * struct rmid_entry - dirty tracking for all RMID.
diff --git a/arch/x86/kernel/cpu/resctrl/monitor_trace.h b/arch/x86/kernel/cpu/resctrl/monitor_trace.h
new file mode 100644
index 000000000000..ade67daf42c2
--- /dev/null
+++ b/arch/x86/kernel/cpu/resctrl/monitor_trace.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM resctrl
+
+#if !defined(_FS_RESCTRL_MONITOR_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _FS_RESCTRL_MONITOR_TRACE_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(mon_llc_occupancy_limbo,
+	    TP_PROTO(u32 ctrl_hw_id, u32 mon_hw_id, int domain_id, u64 llc_occupancy_bytes),
+	    TP_ARGS(ctrl_hw_id, mon_hw_id, domain_id, llc_occupancy_bytes),
+	    TP_STRUCT__entry(__field(u32, ctrl_hw_id)
+			     __field(u32, mon_hw_id)
+			     __field(int, domain_id)
+			     __field(u64, llc_occupancy_bytes)),
+	    TP_fast_assign(__entry->ctrl_hw_id = ctrl_hw_id;
+			   __entry->mon_hw_id = mon_hw_id;
+			   __entry->domain_id = domain_id;
+			   __entry->llc_occupancy_bytes = llc_occupancy_bytes;),
+	    TP_printk("ctrl_hw_id=%u mon_hw_id=%u domain_id=%d llc_occupancy_bytes=%llu",
+		      __entry->ctrl_hw_id, __entry->mon_hw_id, __entry->domain_id,
+		      __entry->llc_occupancy_bytes)
+	   );
+
+#endif /* _FS_RESCTRL_MONITOR_TRACE_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE monitor_trace
+#include <trace/define_trace.h>
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index f671c5dea079..27d2d4e3cf50 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -30,7 +30,7 @@
 #include "internal.h"
 
 #define CREATE_TRACE_POINTS
-#include "trace.h"
+#include "pseudo_lock_trace.h"
 
 /*
  * The bits needed to disable hardware prefetching varies based on the
diff --git a/arch/x86/kernel/cpu/resctrl/trace.h b/arch/x86/kernel/cpu/resctrl/pseudo_lock_trace.h
similarity index 56%
rename from arch/x86/kernel/cpu/resctrl/trace.h
rename to arch/x86/kernel/cpu/resctrl/pseudo_lock_trace.h
index 2a506316b303..5a0fae61d3ee 100644
--- a/arch/x86/kernel/cpu/resctrl/trace.h
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock_trace.h
@@ -2,8 +2,8 @@
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM resctrl
 
-#if !defined(_TRACE_RESCTRL_H) || defined(TRACE_HEADER_MULTI_READ)
-#define _TRACE_RESCTRL_H
+#if !defined(_X86_RESCTRL_PSEUDO_LOCK_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _X86_RESCTRL_PSEUDO_LOCK_TRACE_H
 
 #include <linux/tracepoint.h>
 
@@ -35,25 +35,9 @@ TRACE_EVENT(pseudo_lock_l3,
 	    TP_printk("hits=%llu miss=%llu",
 		      __entry->l3_hits, __entry->l3_miss));
 
-TRACE_EVENT(mon_llc_occupancy_limbo,
-	    TP_PROTO(u32 ctrl_hw_id, u32 mon_hw_id, int domain_id, u64 llc_occupancy_bytes),
-	    TP_ARGS(ctrl_hw_id, mon_hw_id, domain_id, llc_occupancy_bytes),
-	    TP_STRUCT__entry(__field(u32, ctrl_hw_id)
-			     __field(u32, mon_hw_id)
-			     __field(int, domain_id)
-			     __field(u64, llc_occupancy_bytes)),
-	    TP_fast_assign(__entry->ctrl_hw_id = ctrl_hw_id;
-			   __entry->mon_hw_id = mon_hw_id;
-			   __entry->domain_id = domain_id;
-			   __entry->llc_occupancy_bytes = llc_occupancy_bytes;),
-	    TP_printk("ctrl_hw_id=%u mon_hw_id=%u domain_id=%d llc_occupancy_bytes=%llu",
-		      __entry->ctrl_hw_id, __entry->mon_hw_id, __entry->domain_id,
-		      __entry->llc_occupancy_bytes)
-	   );
-
-#endif /* _TRACE_RESCTRL_H */
+#endif /* _X86_RESCTRL_PSEUDO_LOCK_TRACE_H */
 
 #undef TRACE_INCLUDE_PATH
 #define TRACE_INCLUDE_PATH .
-#define TRACE_INCLUDE_FILE trace
+#define TRACE_INCLUDE_FILE pseudo_lock_trace
 #include <trace/define_trace.h>
-- 
2.39.2

[PATCH v4 37/39] fs/resctrl: Add boiler plate for external resctrl code

[James Morse]

Add Makefile and Kconfig for fs/resctrl. Add ARCH_HAS_CPU_RESCTRL
for the common parts of the resctrl interface and make X86_CPU_RESCTRL
depend on this.

Adding an include of asm/resctrl.h to linux/resctrl.h allows some
of the files to switch over to using this header instead.

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
---
Changes since v3:
 * Reworded 'if unsure say N' from the Kconfig text, the user doesn't have
   the choice anyway at this point.
 * Added PWD to monitor.o's CFLAGS for the ftrace rube-goldberg build machine.
 * Added split trace files.

Changes since v2:
 * Dropped KERNFS dependency from arch side Kconfig.
 * Added empty trace.h file.
 * Merged asm->linux includes from Dave's patch to decouple those
   patches from this series.

Changes since v1:
 * Rename new file psuedo_lock.c to pseudo_lock.c, to match the name
   of the original file (and to be less surprising).

 * [Whitespace only] Under RESCTRL_FS in fs/resctrl/Kconfig, delete
   alignment space in orphaned select ... if (which has nothing to line
   up with any more).

 * [Whitespace only] Reflow and re-tab Kconfig additions.
---
 MAINTAINERS                               |  1 +
 arch/Kconfig                              |  8 +++++
 arch/x86/Kconfig                          |  5 +--
 arch/x86/kernel/cpu/resctrl/internal.h    |  3 +-
 arch/x86/kernel/cpu/resctrl/monitor.c     |  2 +-
 arch/x86/kernel/cpu/resctrl/pseudo_lock.c |  2 +-
 arch/x86/kernel/cpu/resctrl/rdtgroup.c    |  2 +-
 fs/Kconfig                                |  1 +
 fs/Makefile                               |  1 +
 fs/resctrl/Kconfig                        | 37 +++++++++++++++++++++++
 fs/resctrl/Makefile                       |  6 ++++
 fs/resctrl/ctrlmondata.c                  |  0
 fs/resctrl/internal.h                     |  0
 fs/resctrl/monitor.c                      |  0
 fs/resctrl/monitor_trace.h                |  0
 fs/resctrl/pseudo_lock.c                  |  0
 fs/resctrl/pseudo_lock_trace.h            |  0
 fs/resctrl/rdtgroup.c                     |  0
 include/linux/resctrl.h                   |  4 +++
 19 files changed, 65 insertions(+), 7 deletions(-)
 create mode 100644 fs/resctrl/Kconfig
 create mode 100644 fs/resctrl/Makefile
 create mode 100644 fs/resctrl/ctrlmondata.c
 create mode 100644 fs/resctrl/internal.h
 create mode 100644 fs/resctrl/monitor.c
 create mode 100644 fs/resctrl/monitor_trace.h
 create mode 100644 fs/resctrl/pseudo_lock.c
 create mode 100644 fs/resctrl/pseudo_lock_trace.h
 create mode 100644 fs/resctrl/rdtgroup.c

diff --git a/MAINTAINERS b/MAINTAINERS
index dcdec2cb7b92..f3631095a4f8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19203,6 +19203,7 @@ S:	Supported
 F:	Documentation/arch/x86/resctrl*
 F:	arch/x86/include/asm/resctrl.h
 F:	arch/x86/kernel/cpu/resctrl/
+F:	fs/resctrl/
 F:	include/linux/resctrl*.h
 F:	tools/testing/selftests/resctrl/
 
diff --git a/arch/Kconfig b/arch/Kconfig
index 975dd22a2dbd..4156604dd926 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1431,6 +1431,14 @@ config STRICT_MODULE_RWX
 config ARCH_HAS_PHYS_TO_DMA
 	bool
 
+config ARCH_HAS_CPU_RESCTRL
+	bool
+	help
+	  An architecture selects this option to indicate that the necessary
+	  hooks are provided to support the common memory system usage
+	  monitoring and control interfaces provided by the 'resctrl'
+	  filesystem (see RESCTRL_FS).
+
 config HAVE_ARCH_COMPILER_H
 	bool
 	help
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 7e908186dc32..61dd5120ab51 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -491,8 +491,9 @@ config X86_MPPARSE
 config X86_CPU_RESCTRL
 	bool "x86 CPU resource control support"
 	depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
-	select KERNFS
-	select PROC_CPU_RESCTRL		if PROC_FS
+	depends on MISC_FILESYSTEMS
+	select ARCH_HAS_CPU_RESCTRL
+	select RESCTRL_FS
 	select RESCTRL_FS_PSEUDO_LOCK
 	help
 	  Enable x86 CPU resource control support.
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index c8086095954b..a3ae7bbed9f8 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -7,10 +7,9 @@
 #include <linux/kernfs.h>
 #include <linux/fs_context.h>
 #include <linux/jump_label.h>
+#include <linux/resctrl.h>
 #include <linux/tick.h>
 
-#include <asm/resctrl.h>
-
 #define L3_QOS_CDP_ENABLE		0x01ULL
 
 #define L2_QOS_CDP_ENABLE		0x01ULL
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index b7662782ea59..9ae709ba5744 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -19,11 +19,11 @@
 
 #include <linux/cpu.h>
 #include <linux/module.h>
+#include <linux/resctrl.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
 
 #include <asm/cpu_device_id.h>
-#include <asm/resctrl.h>
 
 #include "internal.h"
 
diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
index 27d2d4e3cf50..e130f28c1d88 100644
--- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
+++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c
@@ -18,12 +18,12 @@
 #include <linux/mman.h>
 #include <linux/perf_event.h>
 #include <linux/pm_qos.h>
+#include <linux/resctrl.h>
 #include <linux/slab.h>
 #include <linux/uaccess.h>
 
 #include <asm/cacheflush.h>
 #include <asm/cpu_device_id.h>
-#include <asm/resctrl.h>
 #include <asm/perf_event.h>
 
 #include "../../events/perf_event.h" /* For X86_CONFIG() */
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index a7e1a445559f..314aeae99129 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -18,6 +18,7 @@
 #include <linux/fs_parser.h>
 #include <linux/sysfs.h>
 #include <linux/kernfs.h>
+#include <linux/resctrl.h>
 #include <linux/seq_buf.h>
 #include <linux/seq_file.h>
 #include <linux/sched/signal.h>
@@ -28,7 +29,6 @@
 
 #include <uapi/linux/magic.h>
 
-#include <asm/resctrl.h>
 #include "internal.h"
 
 DEFINE_STATIC_KEY_FALSE(rdt_enable_key);
diff --git a/fs/Kconfig b/fs/Kconfig
index a46b0cbc4d8f..d8a36383b6dc 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -331,6 +331,7 @@ source "fs/omfs/Kconfig"
 source "fs/hpfs/Kconfig"
 source "fs/qnx4/Kconfig"
 source "fs/qnx6/Kconfig"
+source "fs/resctrl/Kconfig"
 source "fs/romfs/Kconfig"
 source "fs/pstore/Kconfig"
 source "fs/sysv/Kconfig"
diff --git a/fs/Makefile b/fs/Makefile
index 6ecc9b0a53f2..da6e2d028722 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -129,3 +129,4 @@ obj-$(CONFIG_EFIVAR_FS)		+= efivarfs/
 obj-$(CONFIG_EROFS_FS)		+= erofs/
 obj-$(CONFIG_VBOXSF_FS)		+= vboxsf/
 obj-$(CONFIG_ZONEFS_FS)		+= zonefs/
+obj-$(CONFIG_RESCTRL_FS)	+= resctrl/
diff --git a/fs/resctrl/Kconfig b/fs/resctrl/Kconfig
new file mode 100644
index 000000000000..3a3a75dad40d
--- /dev/null
+++ b/fs/resctrl/Kconfig
@@ -0,0 +1,37 @@
+config RESCTRL_FS
+	bool "CPU Resource Control Filesystem (resctrl)"
+	depends on ARCH_HAS_CPU_RESCTRL
+	select KERNFS
+	select PROC_CPU_RESCTRL if PROC_FS
+	help
+	  Some architectures provide hardware facilities to group tasks and
+	  monitor and control their usage of memory system resources such as
+	  caches and memory bandwidth.  Examples of such facilities include
+	  Intel's Resource Director Technology (Intel(R) RDT) and AMD's
+	  Platform Quality of Service (AMD QoS).
+
+	  If your system has the necessary support and you want to be able to
+	  assign tasks to groups and manipulate the associated resource
+	  monitors and controls from userspace, say Y here to get a mountable
+	  'resctrl' filesystem that lets you do just that.
+
+	  If nothing mounts or prods the 'resctrl' filesystem, resource
+	  controls and monitors are left in a quiescent, permissive state.
+
+	  On architectures where this can be disabled independently, it is
+	  safe to say N.
+
+	  See <file:Documentation/arch/x86/resctrl.rst> for more information.
+
+config RESCTRL_FS_PSEUDO_LOCK
+	bool
+	help
+	  Software mechanism to pin data in a cache portion using
+	  micro-architecture specific knowledge.
+
+config RESCTRL_RMID_DEPENDS_ON_CLOSID
+	bool
+	help
+	  Enable by the architecture when the RMID values depend on the CLOSID.
+	  This causes the closid allocator to search for CLOSID with clean
+	  RMID.
diff --git a/fs/resctrl/Makefile b/fs/resctrl/Makefile
new file mode 100644
index 000000000000..e67f34d2236a
--- /dev/null
+++ b/fs/resctrl/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_RESCTRL_FS)		+= rdtgroup.o ctrlmondata.o monitor.o
+obj-$(CONFIG_RESCTRL_FS_PSEUDO_LOCK)	+= pseudo_lock.o
+
+# To allow define_trace.h's recursive include:
+CFLAGS_monitor.o = -I$(src)
diff --git a/fs/resctrl/ctrlmondata.c b/fs/resctrl/ctrlmondata.c
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/fs/resctrl/internal.h b/fs/resctrl/internal.h
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/fs/resctrl/monitor_trace.h b/fs/resctrl/monitor_trace.h
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/fs/resctrl/pseudo_lock.c b/fs/resctrl/pseudo_lock.c
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/fs/resctrl/pseudo_lock_trace.h b/fs/resctrl/pseudo_lock_trace.h
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index c97ae81a57af..0a8ae7205426 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -9,6 +9,10 @@
 #include <linux/pid.h>
 #include <linux/resctrl_types.h>
 
+#ifdef CONFIG_ARCH_HAS_CPU_RESCTRL
+#include <asm/resctrl.h>
+#endif
+
 /* CLOSID, RMID value used by the default control group */
 #define RESCTRL_RESERVED_CLOSID		0
 #define RESCTRL_RESERVED_RMID		0
-- 
2.39.2

[PATCH v4 38/39] x86/resctrl: Move the filesystem bits to headers visible to fs/resctrl

[James Morse]

Once the filesystem parts of resctrl move to fs/resctrl, it cannot rely
on definitions in x86's internal.h.

Move definitions in internal.h that need to be shared between the
filesystem and architecture code to header files that fs/resctrl can
include.

Doing this separately means the filesystem code only moves between files
of the same name, instead of having these changes mixed in too.

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
---
Changes since v3:
 * Changed the number of hyphens at the end of the commit message.

Changes since v2:
 * Dropped the rfflags and some other defines from being moved.

Changes since v1:
 * Revert apparently unintentional duplication of a couple of variable
   declarations in <linux/resctrl.h>.

   No functional change.
---
 arch/x86/include/asm/resctrl.h         | 3 +++
 arch/x86/kernel/cpu/resctrl/core.c     | 5 +++++
 arch/x86/kernel/cpu/resctrl/internal.h | 9 ---------
 include/linux/resctrl_types.h          | 3 +++
 4 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
index a8bc1d68f889..506ecd04788b 100644
--- a/arch/x86/include/asm/resctrl.h
+++ b/arch/x86/include/asm/resctrl.h
@@ -218,6 +218,9 @@ int resctrl_arch_measure_l2_residency(void *_plr);
 int resctrl_arch_measure_l3_residency(void *_plr);
 void resctrl_cpu_detect(struct cpuinfo_x86 *c);
 
+bool resctrl_arch_get_cdp_enabled(enum resctrl_res_level l);
+int resctrl_arch_set_cdp_enabled(enum resctrl_res_level l, bool enable);
+
 #else
 
 static inline void resctrl_arch_sched_in(struct task_struct *tsk) {}
diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index 568127177a98..b8aa6faf100a 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -285,6 +285,11 @@ static void rdt_get_cdp_l2_config(void)
 	rdt_get_cdp_config(RDT_RESOURCE_L2);
 }
 
+bool resctrl_arch_get_cdp_enabled(enum resctrl_res_level l)
+{
+	return rdt_resources_all[l].cdp_enabled;
+}
+
 static void mba_wrmsr_amd(struct msr_param *m)
 {
 	struct rdt_hw_ctrl_domain *hw_dom = resctrl_to_arch_ctrl_dom(m->dom);
diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index a3ae7bbed9f8..407bc46ba84c 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -17,8 +17,6 @@
 #define CQM_LIMBOCHECK_INTERVAL	1000
 
 #define MBM_CNTR_WIDTH_BASE		24
-#define MBM_OVERFLOW_INTERVAL		1000
-#define MAX_MBA_BW			100u
 #define MBA_IS_LINEAR			0x4
 #define MBM_CNTR_WIDTH_OFFSET_AMD	20
 
@@ -404,13 +402,6 @@ extern struct rdt_hw_resource rdt_resources_all[];
 extern struct rdtgroup rdtgroup_default;
 extern struct dentry *debugfs_resctrl;
 
-static inline bool resctrl_arch_get_cdp_enabled(enum resctrl_res_level l)
-{
-	return rdt_resources_all[l].cdp_enabled;
-}
-
-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);
 
 /* CPUID.(EAX=10H, ECX=ResID=1).EAX */
diff --git a/include/linux/resctrl_types.h b/include/linux/resctrl_types.h
index 70226f5ab3e3..b84a6e0834a7 100644
--- a/include/linux/resctrl_types.h
+++ b/include/linux/resctrl_types.h
@@ -7,6 +7,9 @@
 #ifndef __LINUX_RESCTRL_TYPES_H
 #define __LINUX_RESCTRL_TYPES_H
 
+#define MAX_MBA_BW			100u
+#define MBM_OVERFLOW_INTERVAL		1000
+
 /* Reads to Local DRAM Memory */
 #define READS_TO_LOCAL_MEM		BIT(0)
 
-- 
2.39.2

[PATCH v4 39/39] x86/resctrl: Add python script to move resctrl code to /fs/resctrl

[James Morse]

To support more than one architecture resctrl needs to move from arch/x86
to live under fs. Moving all the code breaks any series on the mailing
list, so needs scheduling carefully.

Maintaining the patch that moves all this code has proved labour intensive.
It's also near-impossible to review that no inadvertent changes have
crept in.

To solve these problems, temporarily add a hacky python program that
lists all the functions that should move, and those that should stay.

No attempt to parse C code is made, this thing tries to name 'blocks'
based on hueristics about the kernel coding style. It's fragile, but
good enough for its single use here.

This causes the original files to be regenerated, which will add
newlines that are not present in the original file.

I don't suggested this gets merged.

Signed-off-by: James Morse <james.morse@arm.com>
---
 resctrl_copy_pasta.py | 779 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 779 insertions(+)
 create mode 100644 resctrl_copy_pasta.py

diff --git a/resctrl_copy_pasta.py b/resctrl_copy_pasta.py
new file mode 100644
index 000000000000..227e67eac4c4
--- /dev/null
+++ b/resctrl_copy_pasta.py
@@ -0,0 +1,779 @@
+#!/usr/bin/python
+import sys;
+import os;
+import re;
+
+############
+
+SRC_DIR = "arch/x86/kernel/cpu/resctrl";
+DST_DIR = "fs/resctrl";
+
+resctrl_files = [
+	"ctrlmondata.c",
+	"internal.h",
+	"monitor.c",
+	"pseudo_lock.c",
+	"rdtgroup.c",
+	"pseudo_lock_trace.h",
+	"monitor_trace.h",
+];
+
+functions_to_keep = [
+	# common
+	"pr_fmt",
+
+	# core.c
+	"domain_list_lock",
+	"resctrl_arch_late_init",
+	"resctrl_arch_exit",
+	"resctrl_cpu_detect",
+	"rdt_cpu_has",
+	"resctrl_arch_is_evt_configurable",
+	"get_mem_config",
+	"get_slow_mem_config",
+	"get_rdt_alloc_resources",
+	"get_rdt_mon_resources",
+	"__check_quirks_intel",
+	"check_quirks",
+	"get_rdt_resources",
+	"rdt_init_res_defs_intel",
+	"rdt_init_res_defs_amd",
+	"rdt_init_res_defs",
+	"resctrl_cpu_detect",
+	"resctrl_arch_late_init",
+	"resctrl_arch_exit",
+	"setup_default_ctrlval",
+	"domain_free",
+	"domain_setup_ctrlval",
+	"arch_domain_mbm_alloc",
+	"domain_add_cpu",
+	"domain_remove_cpu",
+	"clear_closid_rmid",
+	"resctrl_arch_online_cpu",
+	"resctrl_arch_offline_cpu",
+	"resctrl_arch_find_domain",
+	"resctrl_arch_get_num_closid",
+	"rdt_ctrl_update",
+	"domain_init",
+	"resctrl_arch_get_resource",
+	"cache_alloc_hsw_probe",
+	"rdt_get_mb_table",
+	"__get_mem_config_intel",
+	"__rdt_get_mem_config_amd",
+	"rdt_get_cache_alloc_cfg",
+	"rdt_get_cdp_config",
+	"rdt_get_cdp_l3_config",
+	"rdt_get_cdp_l2_config",
+	"resctrl_arch_get_cdp_enabled",
+	"set_rdt_options",
+	"pqr_state",
+	"rdt_resources_all",
+	"delay_bw_map",
+	"rdt_options",
+	"cat_wrmsr",
+	"mba_wrmsr_amd",
+	"mba_wrmsr_intel",
+	"anonymous-enum",
+	"rdt_find_domain",
+	"rdt_alloc_capable",
+	"rdt_online",
+	"RDT_OPT",
+
+	# ctrlmon.c
+	"apply_config",
+	"resctrl_arch_update_one",
+	"resctrl_arch_update_domains",
+	"resctrl_arch_get_config",
+
+	# internal.h
+	"L3_QOS_CDP_ENABLE",
+	"L2_QOS_CDP_ENABLE",
+	"MBM_CNTR_WIDTH_OFFSET_AMD",
+	"arch_mbm_state",
+	"rdt_hw_ctrl_domain",
+	"rdt_hw_mon_domain",
+	"resctrl_to_arch_ctrl_dom",
+	"resctrl_to_arch_mon_dom",
+	"msr_param",
+	"rdt_hw_resource",
+	"resctrl_to_arch_res",
+	"rdt_resources_all",
+	"resctrl_inc",
+	"for_each_rdt_resource",
+	"for_each_capable_rdt_resource",
+	"for_each_alloc_capable_rdt_resource",
+	"for_each_mon_capable_rdt_resource",
+	"arch_mon_domain_online",
+	"cpuid_0x10_1_eax",
+	"cpuid_0x10_3_eax",
+	"cpuid_0x10_x_ecx",
+	"cpuid_0x10_x_edx",
+	"rdt_ctrl_update",
+	"rdt_get_mon_l3_config",
+	"rdt_cpu_has",
+	"intel_rdt_mbm_apply_quirk",
+	"rdt_domain_reconfigure_cdp",
+
+	# monitor.c
+	"rdt_mon_capable",
+	"rdt_mon_features",
+	"CF",
+	"snc_nodes_per_l3_cache",
+	"mbm_cf_table",
+	"mbm_cf_rmidthreshold",
+	"mbm_cf",
+	"logical_rmid_to_physical_rmid",
+	"__rmid_read_phys",
+	"get_corrected_mbm_count",
+	"__rmid_read",
+	"get_arch_mbm_state",
+	"resctrl_arch_reset_rmid",
+	"resctrl_arch_reset_rmid_all",
+	"mbm_overflow_count",
+	"resctrl_arch_rmid_read",
+	"snc_cpu_ids",
+	"snc_get_config",
+	"rdt_get_mon_l3_config",
+	"intel_rdt_mbm_apply_quirk",
+
+	# pseudo_lock.c
+	"prefetch_disable_bits",
+	"resctrl_arch_get_prefetch_disable_bits",
+	"resctrl_arch_pseudo_lock_fn",
+	"resctrl_arch_measure_cycles_lat_fn",
+	"perf_miss_attr",
+	"perf_hit_attr",
+	"residency_counts",
+	"measure_residency_fn",
+	"resctrl_arch_measure_l2_residency",
+	"resctrl_arch_measure_l3_residency",
+
+	# rdtgroup.c
+	"rdt_enable_key",
+	"rdt_mon_enable_key",
+	"rdt_alloc_enable_key",
+	"resctrl_arch_sync_cpu_closid_rmid",
+	"INVALID_CONFIG_INDEX",
+	"mon_event_config_index_get",
+	"resctrl_arch_mon_event_config_read",
+	"resctrl_arch_mon_event_config_write",
+	"l3_qos_cfg_update",
+	"l2_qos_cfg_update",
+	"set_cache_qos_cfg",
+	"rdt_domain_reconfigure_cdp",
+	"cdp_enable",
+	"cdp_disable",
+	"resctrl_arch_set_cdp_enabled",
+	"reset_all_ctrls",
+	"resctrl_arch_reset_resources",
+
+	# pseudo_lock_trace.h
+	"TRACE_SYSTEM",
+	"pseudo_lock_mem_latency",
+	"pseudo_lock_l2",
+	"pseudo_lock_l3",
+];
+
+functions_to_move = [
+	# common
+	"pr_fmt",
+
+	# ctrlmon.c
+	"rdt_parse_data",
+	"(ctrlval_parser_t)",
+	"bw_validate",
+	"parse_bw",
+	"cbm_validate",
+	"parse_cbm",
+	"get_parser",
+	"parse_line",
+	"rdtgroup_parse_resource",
+	"rdtgroup_schemata_write",
+	"show_doms",
+	"rdtgroup_schemata_show",
+	"smp_mon_event_count",
+	"mon_event_read",
+	"rdtgroup_mondata_show",
+
+	# internal.h
+	"MBM_OVERFLOW_INTERVAL",
+	"CQM_LIMBOCHECK_INTERVAL",
+	"cpumask_any_housekeeping",
+	"rdt_fs_context",
+	"rdt_fc2context",
+	"mon_evt",
+	"mon_data_bits",
+	"rmid_read",
+	"resctrl_schema_all",
+	"resctrl_mounted",
+	"rdt_group_type",
+	"rdtgrp_mode",
+	"mongroup",
+	"rdtgroup",
+	"RFTYPE_FLAGS_CPUS_LIST",
+	"rdt_all_groups",
+	"rftype",
+	"mbm_state",
+	"is_mba_sc",
+
+	# monitor.c
+	"rmid_entry",
+	"rmid_free_lru",
+	"closid_num_dirty_rmid",
+	"rmid_limbo_count",
+	"rmid_ptrs",
+	"resctrl_rmid_realloc_threshold",
+	"resctrl_rmid_realloc_limit",
+	"__rmid_entry",
+	"limbo_release_entry",
+	"__check_limbo",
+	"has_busy_rmid",
+	"resctrl_find_free_rmid",
+	"resctrl_find_cleanest_closid",
+	"alloc_rmid",
+	"add_rmid_to_limbo",
+	"free_rmid",
+	"get_mbm_state",
+	"__mon_event_count",
+	"mbm_bw_count",
+	"mon_event_count",
+	"update_mba_bw",
+	"mbm_update",
+	"cqm_handle_limbo",
+	"cqm_setup_limbo_handler",
+	"mbm_handle_overflow",
+	"mbm_setup_overflow_handler",
+	"dom_data_init",
+	"dom_data_exit",
+	"llc_occupancy_event",
+	"mbm_total_event",
+	"mbm_local_event",
+	"l3_mon_evt_init",
+	"resctrl_mon_resource_init",
+	"resctrl_mon_resource_exit",
+
+	# pseudo_lock.c
+	"pseudo_lock_major",
+	"pseudo_lock_minor_avail",
+	"pseudo_lock_devnode",
+	"pseudo_lock_class",
+	"pseudo_lock_minor_get",
+	"pseudo_lock_minor_release",
+	"region_find_by_minor",
+	"pseudo_lock_pm_req",
+	"pseudo_lock_cstates_relax",
+	"pseudo_lock_cstates_constrain",
+	"pseudo_lock_region_clear",
+	"pseudo_lock_region_init",
+	"pseudo_lock_init",
+	"pseudo_lock_region_alloc",
+	"pseudo_lock_free",
+	"rdtgroup_monitor_in_progress",
+	"rdtgroup_locksetup_user_restrict",
+	"rdtgroup_locksetup_user_restore",
+	"rdtgroup_locksetup_enter",
+	"rdtgroup_locksetup_exit",
+	"rdtgroup_cbm_overlaps_pseudo_locked",
+	"rdtgroup_pseudo_locked_in_hierarchy",
+	"pseudo_lock_measure_cycles",
+	"pseudo_lock_measure_trigger",
+	"pseudo_measure_fops",
+	"rdtgroup_pseudo_lock_create",
+	"rdtgroup_pseudo_lock_remove",
+	"pseudo_lock_dev_open",
+	"pseudo_lock_dev_release",
+	"pseudo_lock_dev_mremap",
+	"pseudo_mmap_ops",
+	"pseudo_lock_dev_mmap",
+	"pseudo_lock_dev_fops",
+	"rdt_pseudo_lock_init",
+	"rdt_pseudo_lock_release",
+
+	# rdtgroup.c
+	"rdtgroup_mutex",
+	"rdt_root",
+	"rdtgroup_default",
+	"rdt_all_groups",
+	"resctrl_schema_all",
+	"resctrl_mounted",
+	"kn_info",
+	"kn_mongrp",
+	"kn_mondata",
+	"max_name_width",
+	"last_cmd_status",
+	"last_cmd_status_buf",
+	"rdtgroup_setup_root",
+	"rdtgroup_destroy_root",
+	"debugfs_resctrl",
+	"resctrl_debug",
+	"rdt_last_cmd_clear",
+	"rdt_last_cmd_puts",
+	"rdt_last_cmd_printf",
+	"rdt_staged_configs_clear",
+	"resctrl_is_mbm_enabled",
+	"resctrl_is_mbm_event",
+	"closid_free_map",
+	"closid_free_map_len",
+	"closids_supported",
+	"closid_init",
+	"closid_alloc",
+	"closid_free",
+	"closid_allocated",
+	"rdtgroup_mode_by_closid",
+	"rdt_mode_str",
+	"rdtgroup_mode_str",
+	"rdtgroup_kn_set_ugid",
+	"rdtgroup_add_file",
+	"rdtgroup_seqfile_show",
+	"rdtgroup_file_write",
+	"rdtgroup_kf_single_ops",
+	"kf_mondata_ops",
+	"is_cpu_list",
+	"rdtgroup_cpus_show",
+	"update_closid_rmid",
+	"cpus_mon_write",
+	"cpumask_rdtgrp_clear",
+	"cpus_ctrl_write",
+	"rdtgroup_cpus_write",
+	"rdtgroup_remove",
+	"_update_task_closid_rmid",
+	"update_task_closid_rmid",
+	"task_in_rdtgroup",
+	"__rdtgroup_move_task",
+	"is_closid_match",
+	"is_rmid_match",
+	"rdtgroup_tasks_assigned",
+	"rdtgroup_task_write_permission",
+	"rdtgroup_move_task",
+	"rdtgroup_tasks_write",
+	"show_rdt_tasks",
+	"rdtgroup_tasks_show",
+	"rdtgroup_closid_show",
+	"rdtgroup_rmid_show",
+	"proc_resctrl_show",
+	"rdt_last_cmd_status_show",
+	"rdt_num_closids_show",
+	"rdt_default_ctrl_show",
+	"rdt_min_cbm_bits_show",
+	"rdt_shareable_bits_show",
+	"rdt_bit_usage_show",
+	"rdt_min_bw_show",
+	"rdt_num_rmids_show",
+	"rdt_mon_features_show",
+	"rdt_bw_gran_show",
+	"rdt_delay_linear_show",
+	"max_threshold_occ_show",
+	"rdt_thread_throttle_mode_show",
+	"max_threshold_occ_write",
+	"rdtgroup_mode_show",
+	"resctrl_peer_type",
+	"rdt_has_sparse_bitmasks_show",
+	"__rdtgroup_cbm_overlaps",
+	"rdtgroup_cbm_overlaps",
+	"rdtgroup_mode_test_exclusive",
+	"rdtgroup_mode_write",
+	"rdtgroup_cbm_to_size",
+	"rdtgroup_size_show",
+	"mondata_config_read",
+	"mbm_config_show",
+	"mbm_total_bytes_config_show",
+	"mbm_local_bytes_config_show",
+	"mbm_config_write_domain",
+	"mon_config_write",
+	"mbm_total_bytes_config_write",
+	"mbm_local_bytes_config_write",
+	"res_common_files",
+	"rdtgroup_add_files",
+	"rdtgroup_get_rftype_by_name",
+	"thread_throttle_mode_init",
+	"mbm_config_rftype_init",
+	"rdtgroup_kn_mode_restrict",
+	"rdtgroup_kn_mode_restore",
+	"rdtgroup_mkdir_info_resdir",
+	"fflags_from_resource",
+	"rdtgroup_create_info_dir",
+	"mongroup_create_dir",
+	"is_mba_linear",
+	"mba_sc_domain_allocate",
+	"mba_sc_domain_destroy",
+	"supports_mba_mbps",
+	"set_mba_sc",
+	"kernfs_to_rdtgroup",
+	"rdtgroup_kn_get",
+	"rdtgroup_kn_put",
+	"rdtgroup_kn_lock_live",
+	"rdtgroup_kn_unlock",
+	"rdt_disable_ctx",
+	"rdt_enable_ctx",
+	"schemata_list_add",
+	"schemata_list_create",
+	"schemata_list_destroy",
+	"rdt_get_tree",
+	"rdt_param",
+	"rdt_fs_parameters",
+	"rdt_parse_param",
+	"rdt_fs_context_free",
+	"rdt_fs_context_ops",
+	"rdt_init_fs_context",
+	"rdt_move_group_tasks",
+	"free_all_child_rdtgrp",
+	"rmdir_all_sub",
+	"rdt_kill_sb",
+	"rdt_fs_type",
+	"mon_addfile",
+	"mon_rmdir_one_subdir",
+	"rmdir_mondata_subdir_allrdtgrp",
+	"mon_add_all_files",
+	"mkdir_mondata_subdir",
+	"mkdir_mondata_subdir_allrdtgrp",
+	"mkdir_mondata_subdir_alldom",
+	"mkdir_mondata_all",
+	"cbm_ensure_valid",
+	"__init_one_rdt_domain",
+	"rdtgroup_init_cat",
+	"rdtgroup_init_mba",
+	"rdtgroup_init_alloc",
+	"mkdir_rdt_prepare_rmid_alloc",
+	"mkdir_rdt_prepare_rmid_free",
+	"mkdir_rdt_prepare",
+	"mkdir_rdt_prepare_clean",
+	"rdtgroup_mkdir_mon",
+	"rdtgroup_mkdir_ctrl_mon",
+	"is_mon_groups",
+	"rdtgroup_mkdir",
+	"rdtgroup_rmdir_mon",
+	"rdtgroup_ctrl_remove",
+	"rdtgroup_rmdir_ctrl",
+	"rdtgroup_rmdir",
+	"mongrp_reparent",
+	"rdtgroup_rename",
+	"rdtgroup_show_options",
+	"rdtgroup_kf_syscall_ops",
+	"rdtgroup_setup_root",
+	"rdtgroup_destroy_root",
+	"rdtgroup_setup_default",
+	"domain_destroy_mon_state",
+	"resctrl_offline_ctrl_domain",
+	"resctrl_offline_mon_domain",
+	"domain_setup_mon_state",
+	"resctrl_online_ctrl_domain",
+	"resctrl_online_mon_domain",
+	"resctrl_online_cpu",
+	"clear_childcpus",
+	"resctrl_offline_cpu",
+	"resctrl_init",
+	"resctrl_exit",
+
+	# monitor_trace.h
+	"TRACE_SYSTEM",
+	"mon_llc_occupancy_limbo",
+];
+
+############
+
+builtin_non_functions = ["__setup", "__exitcall", "__printf"];
+builtin_one_arg_macros = ["LIST_HEAD", "DEFINE_MUTEX", "DEFINE_STATIC_KEY_FALSE"];
+types = ["bool",  "char", "int", "u32", "long", "u64"];
+
+def get_array_name(line):
+  tok = re.search(r'([^\s]+?)\[\]', line)
+  if (tok is None):
+    return None;
+  return tok.group(1);
+
+
+def get_struct_name(line):
+  tok = re.search(r'struct ([^\s]+?) {', line)
+  if (tok is None):
+    return None;
+  return tok.group(1);
+
+def get_enum_name(line):
+  tok = re.search(r'enum ([^\s]+?) {', line)
+  if (tok is None):
+    return None;
+  return tok.group(1);
+
+def get_union_name(line):
+  tok = re.search(r'union ([^\s]+?) {', line)
+  if (tok is None):
+    return None;
+  return tok.group(1);
+
+
+def get_macro_name(line):
+  tok = re.search(r'#define[\s]+([^\s]+?)\(', line)
+  if (tok):
+    return tok.group(1);
+
+  tok = re.search(r'#define[\s]+([^\s]+?)[\s]+[^\s]+?\n', line)
+  if (tok):
+    return tok.group(1);
+
+  return None;
+
+
+def get_macro_target(line):
+  tok = re.search(r'[^\s]+?\(([^\s]+?)\);\n', line)
+  if (tok):
+    return tok.group(1);
+
+  return None;
+
+
+# Things like 'bool my_bool;'
+def get_object_name(line):
+  # remove things that don't change the meaning of the name
+  if line.startswith("static "):
+    line = line[len("static "):];
+  if line.startswith("extern "):
+    line = line[len("extern "):];
+  if line.startswith("unsigned "):
+    line = line[len("unsigned "):];
+
+  # Note the trailing semicolon..
+  tok = re.search(r'([^\s]+)\s[\*]*([^\s\[\],;]+)', line)
+  if tok:
+    if tok.group(1) in types:
+      return tok.group(2);
+
+  tok = re.search(r'struct\s[^\s]+\s[\*]*([^\s;]+)', line)
+  if tok:
+    return tok.group(1);
+
+  tok = re.search(r'enum\s[^\s]+\s([^\s;]+)', line)
+  if tok:
+    return tok.group(1);
+
+  return None;
+
+
+# Is there a name for this block of code?
+#
+# Function names are the token before '(' ... assuming there is only one '('.
+# This also handles structs and arrays,
+def get_block_name(line):
+  # remove things that don't change the meaning of the name
+  if (" __read_mostly" in line):
+    line = line.replace(" __read_mostly", "");
+  if (" __initconst" in line):
+    line = line.replace(" __initconst", "");
+
+  if line == "enum {\n":
+    return "anonymous-enum";
+  if (line.startswith("#define ")):
+    return get_macro_name(line);
+
+  if ("=" in line):
+    tok = re.search(r'[\*]*([^\s\[\]]+?)[\s\[\]]*=', line)
+  else:
+    tok = re.search(r'[\*]*([^\s]+?)\(.+?', line)
+
+  if (tok is None):
+    if ("[]" in line):
+      return get_array_name(line);
+    if (line.startswith("struct") and line.endswith("{\n")):
+      return get_struct_name(line);
+    if (line.startswith("enum") and line.endswith("{\n")):
+      return get_enum_name(line);
+    if (line.startswith("union") and line.endswith("{\n")):
+      return get_union_name(line);
+    if (line.endswith(";\n") and '(' not in line):
+      return get_object_name(line);
+    if (line.endswith("= {\n") and '(' not in line):
+      return get_object_name(line);
+    return None;
+
+  func_name = tok.group(1);
+  if (func_name in builtin_one_arg_macros):
+    tok = re.search(r'[^\(]+\(([^\s]+?)\)', line)
+    if (tok is None):
+      return None;
+    return tok.group(1);
+  elif (func_name == "DEFINE_PER_CPU"):
+    tok = re.search(r'DEFINE_PER_CPU\(.+?, ([^\s]+?)\)', line)
+    if (tok is None):
+      return None;
+    return tok.group(1);
+  elif (func_name == "TRACE_EVENT"):
+    tok = re.search(r'TRACE_EVENT\((.+?),', line)
+    if (tok is None):
+      return None;
+    return tok.group(1);
+  elif (func_name == "late_initcall"):
+    return get_macro_target(line);
+  else:
+    return func_name;
+
+def output_function_body(body, file):
+  # Mandatory whitespace between blocks
+  if os.lseek(file.fileno(), 0, os.SEEK_CUR) > 0:
+    file.write("\n".encode());
+
+  for out_line in body:
+    file.write(out_line.encode());
+
+# Where should we put this block of code?
+def output_function(name, body, files):
+  output = False;
+  (new_src, new_dst) = files;
+
+  if (len(body)) == 0:
+    return;
+
+  # Output to both files
+  if (name is None):
+    output_function_body(body, new_src);
+    output_function_body(body, new_dst);
+    output = True;
+  if (name in functions_to_keep):
+    output_function_body(body, new_src);
+    output = True;
+  if (name in functions_to_move):
+    output_function_body(body, new_dst);
+    output = True;
+
+  if not output:
+    print("Missing function name: "+name);
+    #print(body);
+
+def reset_parser():
+  global function_name;
+  global define_name;
+  global function_body;
+  global in_define;
+
+  function_name = None;
+  define_name = None;
+  function_body = [];
+  in_define = False;
+
+############
+
+for file in resctrl_files:
+  function_name = None;
+  # function_names take priority over defines, this is only used when
+  # no function_name was found
+  define_name = None;
+  function_body = [];
+  # Nothing clever - this is just to detect newlines between functions
+  in_function = False;
+  in_define = False;
+
+  src_path = SRC_DIR + "/" + str(file);
+  if (not os.path.isfile(src_path)):
+    continue;
+  dst_path = DST_DIR + "/" + str(file);
+
+  orig_file = open(src_path, "r");
+  lines = orig_file.readlines();
+
+  # Now unlink the original file, so it can be re-created with new
+  # contents.
+  try:
+    os.unlink(src_path);
+  except Exception as err:
+    print("Failed to unlink source file: {err}");
+    sys.exit(1);
+
+  # non-buffering is so we can snoop the fd offset to avoid trailing newlines
+  new_src = open(src_path, "wb", buffering=0);
+  new_dst = open(dst_path, "wb", buffering=0);
+
+  for line in lines:
+    # Empty lines outside a function - reset the function tracking
+    if (line == "\n" and not in_function):
+      if function_name is None and define_name is not None:
+        function_name = define_name;
+      output_function(function_name, function_body, (new_src, new_dst));
+      reset_parser();
+
+    # Function prototypes are a funny C thing - reset the function tracking
+    elif (line[0].isspace() and not in_function and line.endswith(");\n")):
+      function_body += [line];
+      output_function(function_name, function_body, (new_src, new_dst));
+      reset_parser();
+
+    # Lines that begin with whitespace are part of the current function.
+    elif (line[0].isspace()):
+      function_body += [line];
+
+    # Next, try to find the kind of line that contains a function name
+
+    # Ignore lines with comment markers, braces
+    elif (line.startswith("/*")):
+      function_body += [line];
+    elif (line.startswith("*/")):
+      function_body += [line];
+    elif (line.startswith("//")):
+      function_body += [line];
+    elif (line == "{\n"):
+      function_body += [line];
+      in_function = True;
+    elif (line == "}\n"):
+      function_body += [line];
+      in_function = False;
+    elif (line == "};\n"):
+      function_body += [line];
+      in_function = False;
+
+    elif (line.startswith("#include")):
+      function_body += [line];
+    elif (line.startswith("#if ")):
+      function_body += [line];
+    elif (line.startswith("#ifdef ")):
+      function_body += [line];
+    elif (line.startswith("#ifndef ")):
+      function_body += [line];
+    elif (line.startswith("#else")):
+      function_body += [line];
+    elif (line.startswith("#endif")):
+      function_body += [line];
+    elif (line.startswith("#undef ")):
+      function_body += [line];
+    elif (line.startswith("#define")):
+      function_body += [line];
+      define_name = get_block_name(line);
+      if line.endswith("\\\n"):
+        in_define = True;
+    elif in_define and line.endswith("\\\n"):
+      function_body += [line];
+
+    # goto was always a crime
+    elif (' ' not in line and line.endswith(":\n")):
+      function_body += [line];
+
+    # Try and parse a function/array name
+
+    # Things like late_initcall() aren't function names, but belong to
+    # the previous function.
+    elif (get_block_name(line) in builtin_non_functions):
+      function_body += [line];
+
+    # Start a new block if we can get a block name for this line
+    elif (get_block_name(line) != None and function_name is None):
+      _name = get_block_name(line);
+
+      if (line.endswith("{\n")):
+        in_function = True;
+
+      # Is this a function prototype? Output it now
+      if (line.endswith(";\n")):
+        function_body += [line];
+        output_function(_name, function_body, (new_src, new_dst));
+        reset_parser();
+      else:
+        function_name = _name;
+        function_body += [line];
+
+    # Failed to parse a function name ... did it get split up?
+    elif (line.startswith("static")):
+      function_body += [line];
+
+    else:
+       print("Unknown: '" + line + "'");
+
+  # Output whatever is left in the buffer
+  output_function(function_name, function_body, (new_src, new_dst));
+
+  orig_file.close();
-- 
2.39.2

RE: [PATCH v4 00/39] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[Shaopeng Tan (Fujitsu)]

Hello James

I ran resctrl selftest on Intel(R) Xeon(R) Gold 6254 CPU, there is no problem.

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

Best regards,
Shaopeng TAN

Re: [PATCH v4 03/39] x86/resctrl: Remove fflags from struct rdt_resource

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> 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 exopsed in the filesystem.

exopsed -> exposed

> 
> 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>
> ---

...

> @@ -2180,14 +2194,14 @@ 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)

Please squash the change in next patch that removes the extra spaces here.

Reinette

Re: [PATCH v4 04/39] x86/resctrl: Use schema type to determine how to parse schema values

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
> index 9ca542a8e2d4..57c88e1c2adf 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[] = {
>   			.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[] = {
>   			.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 +98,11 @@ struct rdt_hw_resource rdt_resources_all[] = {
>   			.name			= "MB",
>   			.ctrl_scope		= RESCTRL_L3_CACHE,
>   			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_MBA),
> -			.parse_ctrlval		= parse_bw,
> +			/*
> +			 * MBA schema_fmt is modified by
> +			 * __rdt_get_mem_config_amd()
> +			 */
> +			.schema_fmt		= RESCTRL_SCHEMA_PERCENTAGE,
>   			.format_str		= "%d=%*u",
>   		},
>   	},
> @@ -109,7 +113,7 @@ struct rdt_hw_resource rdt_resources_all[] = {
>   			.name			= "SMBA",
>   			.ctrl_scope		= RESCTRL_L3_CACHE,
>   			.ctrl_domains		= ctrl_domain_init(RDT_RESOURCE_SMBA),
> -			.parse_ctrlval		= parse_bw,
> +			.schema_fmt		= RESCTRL_SCHEMA_MBPS,
>   			.format_str		= "%d=%*u",
>   		},
>   	},

...

> @@ -195,6 +204,19 @@ int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
>   	return 0;
>   }
>   
> +static ctrlval_parser_t *get_parser(struct rdt_resource *r)
> +{
> +	switch (r->schema_fmt) {
> +	case RESCTRL_SCHEMA_BITMAP:
> +		return &parse_cbm;
> +	case RESCTRL_SCHEMA_PERCENTAGE:
> +	case RESCTRL_SCHEMA_MBPS:
> +		return &parse_bw;
> +	}
> +
> +	return NULL;
> +}
> +
>   /*
>    * For each domain in this resource we expect to find a series of:
>    *	id=mask

...

> @@ -192,6 +191,18 @@ 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_PERCENTAGE:	The schema is a decimal percentage value.
> + * @RESCTRL_SCHEMA_MBPS:	The schema is a decimal MBps value.
> + */
> +enum resctrl_schema_fmt {
> +	RESCTRL_SCHEMA_BITMAP,
> +	RESCTRL_SCHEMA_PERCENTAGE,
> +	RESCTRL_SCHEMA_MBPS,
> +};
> +

I believe that the choice of RESCTRL_SCHEMA_PERCENTAGE and RESCTRL_SCHEMA_MBPS has
potential for significant confusion. The closest place to where user space can enter
a MBps value (which is actually MiBps) is on Intel when resctrl is mounted with mba_MBps,
and as per above it will have the "RESCTRL_SCHEMA_PERCENTAGE" format. What is considered
here as RESCTRL_SCHEMA_MBPS also cannot really be considered as "MBPS" since it is used to
cover AMD's values that are "multiples of one eighth GB/s". Any new resource that
_actually_ uses MBPS will thus not be able to use RESCTRL_SCHEMA_MBPS.

Considering that RESCTRL_SCHEMA_PERCENTAGE and RESCTRL_SCHEMA_MBPS use the same parser,
could "RESCTRL_SCHEMA_RANGE" be more fitting? I acknowledge that it is very generic and better
ideas are welcome. A "range" does seem to be appropriate considering the later patch (x86/resctrl:
Add max_bw to struct resctrl_membw) that codes an explicit max.

Reinette

Re: [PATCH v4 05/39] x86/resctrl: Use schema type to determine the schema format string

[Reinette Chatre]

On 8/2/24 10:28 AM, James Morse wrote:
> @@ -255,6 +253,7 @@ 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

nit: please follow style where all sentences in this portion end with a period/full-stop.

>    * @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.
> @@ -265,6 +264,7 @@ 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;

Re: [PATCH v4 06/39] x86/resctrl: Move data_width to be a schema property

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> The resctrl architecture code gets to specify the width of the schema
> entries that are used by resctrl. These are determined by the schema
> format, e.g. percentage or bitmap.
> 
> Move this property into struct resctrl_schema and get the filesystem
> parts of resctrl to set it based on the schema format. Remove
> rdt_init_padding(), its work is be done by schemata_list_add(),

"its work is be done by" -> "its work is done by"

> allowing max_name_width and max_data_width to be moved out of core.c
> which has no counterpart after the move to fs.
> 
> The logic for calculating max_name_width was moved in earlier patches,

("patches" in changelog can be a trigger, maybe "moved in earlier patches"
-> "moved earlier"?)

> but the definition was not moved.
> 
> Signed-off-by: James Morse <james.morse@arm.com>
> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
> ---
> Changes since v3:
>   * Moved some words around in the commit message - maybe this is the right mood?
>   * Added a full-stop to an existing comment.
> 
> Changes since v2:
>   * This patch is new.
> ---
>   arch/x86/kernel/cpu/resctrl/core.c     | 26 --------------------------
>   arch/x86/kernel/cpu/resctrl/rdtgroup.c | 11 +++++++++++
>   include/linux/resctrl.h                |  4 ++--
>   3 files changed, 13 insertions(+), 28 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
> index f16014ee48aa..cb1d634274b4 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.
> @@ -224,7 +218,6 @@ static 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;
> @@ -264,8 +257,6 @@ static 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;
>   
> @@ -285,7 +276,6 @@ 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;
> @@ -781,20 +771,6 @@ 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,
> @@ -1092,8 +1068,6 @@ 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/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index 1ce851447923..ed06384f9161 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 and max resource data width
> + * to display the schemata in a tabular format.
> + */
> +int max_name_width, max_data_width;
> +
>   static struct seq_buf last_cmd_status;
>   static char last_cmd_status_buf[512];
>   
> @@ -2603,15 +2609,20 @@ 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->data_width = (r->cache.cbm_len + 3) / 4;
>   		break;
>   	case RESCTRL_SCHEMA_PERCENTAGE:
>   		s->fmt_str = "%d=%0*u";
> +		s->data_width = 3;
>   		break;
>   	case RESCTRL_SCHEMA_MBPS:
>   		s->fmt_str = "%d=%0*u";
> +		s->data_width = 4;
>   		break;
>   	}
>   
> +	max_data_width = max(max_data_width, s->data_width);
> +

To me this emphasizes that RESCTRL_SCHEMA_PERCENTAGE and
RESCTRL_SCHEMA_MBPS are not appropriate. Note how the minimum data width
of RESCTRL_SCHEMA_MBPS is 4, this is unexpected from an actual MBps
value. The choice of "4" is specific to AMD's input but that information
is lost in this change.
We are fortunate that data_width is a minimum, allowing the software controller
to be enabled with longer data values, but that is subtle and already
breaks the goal of "making things tabular".

I wonder how useful the data_width actually is. The "make things tabular"
motivation seems to only apply to resources that have the exact same scope
and as noted earlier seems to be broken already.
I am skeptical that user space will be impacted if this is removed.

Reinette

Re: [PATCH v4 07/39] x86/resctrl: Add max_bw to struct resctrl_membw

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> __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.
> 
> Add a max_bw property for AMD platforms to specify their maximum

"for AMD platforms" -> "for x86 platforms"?

> MBA bandwidth. This 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

...

> @@ -108,8 +108,9 @@ 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) - 1;

hmmm ... should this be:
	u32 supported_bits = BIT_MASK(r->cache.cbm_len) - 1;

Reinette

Re: [PATCH v4 08/39] x86/resctrl: Generate default_ctrl instead of sharing it

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:

> +/**
> + * 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_PERCENTAGE:
> +		return 100u;
> +	case RESCTRL_SCHEMA_MBPS:
> +		return r->membw.max_bw;
> +	}
> +
> +	return WARN_ON_ONCE(1);
> +}
> +

I am concerned where this is headed. Since RESCTRL_SCHEMA_PERCENTAGE remains
in use when resctrl is mounted with mba_MBps the default cannot always
be 100u (it should be MBA_MAX_MBPS when software controller is active).

Reinette

Re: [PATCH v4 11/39] x86/resctrl: Export resctrl fs's init function

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> rdtgroup_init() needs exporting so that arch code can call it once
> it lives in core code. As this is one of the few functions exported,
> rename it to have "resctrl" in the name. The same goes for the exit
> call.
> 
> x86's arch code init functions for RDT are renamed to have an arch
> prefix to make it clear these are part of the architecture code.

Please use imperative tone ... for example:
"Rename x86's arch code init functions ..."

Reinette

Re: [PATCH v4 15/39] x86/resctrl: Move monitor exit work to a resctrl exit call

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> 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
> ---
> 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.

Is this still relevant? It is unclear to me why __exit is dropped here.

> 
> 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 4a0dbdc2da4d..9d4d64b4e357 100644
> --- a/arch/x86/kernel/cpu/resctrl/core.c
> +++ b/arch/x86/kernel/cpu/resctrl/core.c
> @@ -1101,14 +1101,9 @@ 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 d355aa676158..3fdeca6e3d21 100644
> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> @@ -579,7 +579,7 @@ 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 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 9cdca9d2bbde..afbda09aacf5 100644
> --- a/arch/x86/kernel/cpu/resctrl/monitor.c
> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
> @@ -1044,10 +1044,13 @@ static int dom_data_init(struct rdt_resource *r)
>   	return err;
>   }
>   
> -static void __exit dom_data_exit(void)
> +static void 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;
> @@ -1056,6 +1059,7 @@ static void __exit dom_data_exit(void)
>   	kfree(rmid_ptrs);
>   	rmid_ptrs = NULL;
>   
> +out_unlock:
>   	mutex_unlock(&rdtgroup_mutex);
>   }
>   
> @@ -1238,9 +1242,11 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
>   	return 0;
>   }
>   
> -void __exit rdt_put_mon_l3_config(void)
> +void 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 1597add37b97..576f6b183980 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> @@ -4291,4 +4291,6 @@ 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();
>   }

Reinette

Re: [PATCH v4 19/39] x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> 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 mbm_config_rftype_init() to create
> the files that allow the configuration.
> 
> Splitting this into separate architecture and filesystem parts would
> require the struct mon_evt and mbm_config_rftype_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
> mbm_config_rftype_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.
> 
> resctrl_arch_is_evt_configurable() uses rdt_cpu_has() from
> resctrl_mon_resource_init(), which isn't marked __init. In addition,

"which isn't marked __init" ... this is no longer accurate, which seems
to indicate that this argument is artifact of this series.

Reinette

Re: [PATCH v4 20/39] x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> @@ -1617,14 +1612,15 @@ static void mon_event_config_read(void *info)
>   	mon_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 = {0};
> +	struct resctrl_mon_config_info mon_info = {0};
>   	struct rdt_mon_domain *dom;
>   	bool sep = false;
>   

Patch looks good, just a fyi:
https://lore.kernel.org/lkml/b2ebc809c8b6c6440d17b12ccf7c2d29aaafd488.1720868538.git.christophe.jaillet@wanadoo.fr

Reinette

Re: [PATCH v4 23/39] x86/resctrl: Allow an architecture to disable pseudo lock

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> 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 file.

"last_cmd file" -> "last_cmd_status file"

Reinette

Re: [PATCH v4 37/39] fs/resctrl: Add boiler plate for external resctrl code

[Reinette Chatre]

Hi James,

On 8/2/24 10:28 AM, James Morse wrote:
> Add Makefile and Kconfig for fs/resctrl. Add ARCH_HAS_CPU_RESCTRL
> for the common parts of the resctrl interface and make X86_CPU_RESCTRL
> depend on this.

It does not sound accurate to say that X86_CPU_RESCTRL depends on
ARCH_HAS_CPU_RESCTRL when actually X86_CPU_RESCTRL "selects" ARCH_HAS_CPU_RESCTRL.

> 
> Adding an include of asm/resctrl.h to linux/resctrl.h allows some
> of the files to switch over to using this header instead.

Please replace the vague "some of the files" with accurate information about how
files to switch over are chosen.

Reinette

RE: [PATCH v4 17/39] x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkers

[Shaopeng Tan (Fujitsu)]

Hello James,

> Subject: [PATCH v4 17/39] 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 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 the core header so existing x86 arch code continues to use them.
> 
> Signed-off-by: James Morse <james.morse@arm.com>
> ---
> 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 8e52e81a044b..84e0d019423d 100644
> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> @@ -472,14 +472,6 @@ extern struct rdt_hw_resource rdt_resources_all[];
> extern struct rdtgroup rdtgroup_default;  extern struct dentry
> *debugfs_resctrl;
> 
> -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; @@ -489,27 +481,6 @@ 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
> c8cd6dde91ed..04a410a5e739 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)->rid < RDT_NUM_RESOURCES - 1;
> 		\
> +	     (_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)
> +

ERROR: Macros with complex values should be enclosed in parentheses

Best regards,
Shaopeng TAN

RE: [PATCH v4 00/39] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[Shaopeng Tan (Fujitsu)]

Hello James,

I have no other problems with this series.
reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>

Best regards,
Shaopeng TAN

Re: [PATCH v4 04/39] x86/resctrl: Use schema type to determine how to parse schema values

[James Morse]

Hi Reinette,

On 14/08/2024 04:56, Reinette Chatre wrote:
> On 8/2/24 10:28 AM, James Morse wrote:
>> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
>> index 9ca542a8e2d4..57c88e1c2adf 100644
>> --- a/arch/x86/kernel/cpu/resctrl/core.c
>> +++ b/arch/x86/kernel/cpu/resctrl/core.c

>> @@ -192,6 +191,18 @@ 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_PERCENTAGE:    The schema is a decimal percentage value.
>> + * @RESCTRL_SCHEMA_MBPS:    The schema is a decimal MBps value.
>> + */
>> +enum resctrl_schema_fmt {
>> +    RESCTRL_SCHEMA_BITMAP,
>> +    RESCTRL_SCHEMA_PERCENTAGE,
>> +    RESCTRL_SCHEMA_MBPS,
>> +};
>> +
> 
> I believe that the choice of RESCTRL_SCHEMA_PERCENTAGE and RESCTRL_SCHEMA_MBPS has
> potential for significant confusion. The closest place to where user space can enter
> a MBps value (which is actually MiBps) is on Intel when resctrl is mounted with mba_MBps,
> and as per above it will have the "RESCTRL_SCHEMA_PERCENTAGE" format.

It was AMD's QOS that I was thinking of. To pick the example from the documentation:
| For example, to allocate 2GB/s limit on the first cache id:
|    MB:0=2048;1=2048;2=2048;3=2048

How does user-space know that its not a percentage? Suck it and see...
If those values aren't in MB/s ... I'm not sure what they are.


The schema format isn't exposed to user-space. (I think we should do that).
I agree if it were, we'd need to report MBps/MiBps for the mba_sc case.


> What is considered
> here as RESCTRL_SCHEMA_MBPS also cannot really be considered as "MBPS" since it is used to
> cover AMD's values that are "multiples of one eighth GB/s". Any new resource that
> _actually_ uses MBPS will thus not be able to use RESCTRL_SCHEMA_MBPS.

Isn't this already covered by the granularity?
AMD platforms are unfortunately reporting '1' as the granularity.
From the 1/8th GB/s it sounds like the granularity should really be 128 MB/s.

Any platform that did have a real MB/s control could report whatever granularity it really
has here.


> Considering that RESCTRL_SCHEMA_PERCENTAGE and RESCTRL_SCHEMA_MBPS use the same parser,
> could "RESCTRL_SCHEMA_RANGE" be more fitting? I acknowledge that it is very generic and
> better
> ideas are welcome. A "range" does seem to be appropriate considering the later patch
> (x86/resctrl:

> Add max_bw to struct resctrl_membw) that codes an explicit max.

Yes because the AMD platforms have a firmware-advertised maximum value, I presume that is
an achievable bandwidth. (otherwise why advertise it to user-space!).
(I'm not sure why data_width is 4 - it looks like that was the hard coded based on one
 platforms limit ... that probably needs fixing too)

But if you had a MBps control, I'm not sure that implies you know what the maximum
achievable bandwidth is. The control may have a range based on some power of two, which is
unrelated to the bandwidth.
In the arm world the hardware never knows what the achievable bandwidth is - that is
something only the SoC designer can work out.


I agree we can parse both values as a range, as resctrl doesn't need to interpret the
values, its just whatever the hardware does.

I did it like this as I'd like to expose "percentage/MBps/bitmap" to user-space so that
control types user-space doesn't recognised can be programmed. If arm64 and riscv each
want to add new schema types, it would be good to do it in a way that is low-impact for
the resctrl filesystem code, and unaware user-space can do something with.
percentage/MBps/bitmap are the control schemes we already have.

The MBps/range difference matters if the 'maximum bandwidth' isn't actually an achievable
number e.g. ~0, then user-space can't treat it as some kind of percentage.


Thanks,

James

Re: [PATCH v4 08/39] x86/resctrl: Generate default_ctrl instead of sharing it

[James Morse]

Hi Reinette,

On 14/08/2024 05:00, Reinette Chatre wrote:
> On 8/2/24 10:28 AM, James Morse wrote:
> 
>> +/**
>> + * 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_PERCENTAGE:
>> +        return 100u;
>> +    case RESCTRL_SCHEMA_MBPS:
>> +        return r->membw.max_bw;
>> +    }
>> +
>> +    return WARN_ON_ONCE(1);
>> +}
>> +

> I am concerned where this is headed. Since RESCTRL_SCHEMA_PERCENTAGE remains
> in use when resctrl is mounted with mba_MBps the default cannot always
> be 100u (it should be MBA_MAX_MBPS when software controller is active).

I agree - and we can certainly tidy that up.
But today when mba_sc is enable the bandwidth_gran and min-bandwidth files both report
'10' (%?), which isn't particularly meaningful.
I think these should both report '1'. There will be a minimum bandwidth, buts it not
something that can be discovered by the mba_sc code.

This was an oversight because the mba_sc mode doesn't update default_ctrl or the format
strings - it hijacks the parsing elsewhere. The default_ctrl isn't visible to user-space,
the value used when reading the schema file comes from the mbps_val array, instead of
ctrl_val.


Some of this has been booted over the horizon - I'll add straightening out the mba_sc
behaviour here to that list.



Thanks,

James

Re: [PATCH v4 06/39] x86/resctrl: Move data_width to be a schema property

[James Morse]

Hi Reinette,

On 14/08/2024 04:59, Reinette Chatre wrote:
> On 8/2/24 10:28 AM, James Morse wrote:
>> The resctrl architecture code gets to specify the width of the schema
>> entries that are used by resctrl. These are determined by the schema
>> format, e.g. percentage or bitmap.
>>
>> Move this property into struct resctrl_schema and get the filesystem
>> parts of resctrl to set it based on the schema format. Remove
>> rdt_init_padding(), its work is be done by schemata_list_add(),
> 
> "its work is be done by" -> "its work is done by"
> 
>> allowing max_name_width and max_data_width to be moved out of core.c
>> which has no counterpart after the move to fs.
>>
>> The logic for calculating max_name_width was moved in earlier patches,
> 
> ("patches" in changelog can be a trigger, maybe "moved in earlier patches"
> -> "moved earlier"?)
> 
>> but the definition was not moved.


>> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> index 1ce851447923..ed06384f9161 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 and max resource data width
>> + * to display the schemata in a tabular format.
>> + */
>> +int max_name_width, max_data_width;
>> +
>>   static struct seq_buf last_cmd_status;
>>   static char last_cmd_status_buf[512];
>>   @@ -2603,15 +2609,20 @@ 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->data_width = (r->cache.cbm_len + 3) / 4;
>>           break;
>>       case RESCTRL_SCHEMA_PERCENTAGE:
>>           s->fmt_str = "%d=%0*u";
>> +        s->data_width = 3;
>>           break;
>>       case RESCTRL_SCHEMA_MBPS:
>>           s->fmt_str = "%d=%0*u";
>> +        s->data_width = 4;
>>           break;
>>       }
>>   +    max_data_width = max(max_data_width, s->data_width);
>> +
> 
> To me this emphasizes that RESCTRL_SCHEMA_PERCENTAGE and
> RESCTRL_SCHEMA_MBPS are not appropriate. Note how the minimum data width
> of RESCTRL_SCHEMA_MBPS is 4, this is unexpected from an actual MBps
> value. The choice of "4" is specific to AMD's input but that information
> is lost in this change.

It's preserving the current behaviour, as AMD is currently the only user.
I strongly suspect the value here is quite wrong, and what we should really do is call
snprintf() to tell us how long the string needs to be.


> We are fortunate that data_width is a minimum, allowing the software controller
> to be enabled with longer data values, but that is subtle and already
> breaks the goal of "making things tabular".

> I wonder how useful the data_width actually is. The "make things tabular"
> motivation seems to only apply to resources that have the exact same scope
> and as noted earlier seems to be broken already.

> I am skeptical that user space will be impacted if this is removed.

Makes sense. I think the only argument could be a parser written for a new kernel would be
surprised if it ran against an older kernel - and we might not care about that scenario.

I can't see how this would happen for the zero-padded values - you'd be going out of your
way to remove leading zeros before working with the field as a number.
It may be a problem for the names which have extra spaces. From what I can tell, an AMD
platform with SMBA must look like something like this:
| SMBA:0=2048
|   L3:0=00ff

I'll rip out the data_width - as fixing it, and making it a property resctrl determines
for itself is going to lead to boat over time for no benefit. I'll leave the name_width as
its marginally plausible a regex like "^L3" would misbehave with different kernel versions
on the same machine.


Thanks,

James

Re: [PATCH v4 04/39] x86/resctrl: Use schema type to determine how to parse schema values

[Reinette Chatre]

Hi James,

On 9/6/24 11:06 AM, James Morse wrote:
> Hi Reinette,
> 
> On 14/08/2024 04:56, Reinette Chatre wrote:
>> On 8/2/24 10:28 AM, James Morse wrote:
>>> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
>>> index 9ca542a8e2d4..57c88e1c2adf 100644
>>> --- a/arch/x86/kernel/cpu/resctrl/core.c
>>> +++ b/arch/x86/kernel/cpu/resctrl/core.c
> 
>>> @@ -192,6 +191,18 @@ 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_PERCENTAGE:    The schema is a decimal percentage value.
>>> + * @RESCTRL_SCHEMA_MBPS:    The schema is a decimal MBps value.
>>> + */
>>> +enum resctrl_schema_fmt {
>>> +    RESCTRL_SCHEMA_BITMAP,
>>> +    RESCTRL_SCHEMA_PERCENTAGE,
>>> +    RESCTRL_SCHEMA_MBPS,
>>> +};
>>> +
>>
>> I believe that the choice of RESCTRL_SCHEMA_PERCENTAGE and RESCTRL_SCHEMA_MBPS has
>> potential for significant confusion. The closest place to where user space can enter
>> a MBps value (which is actually MiBps) is on Intel when resctrl is mounted with mba_MBps,
>> and as per above it will have the "RESCTRL_SCHEMA_PERCENTAGE" format.
> 
> It was AMD's QOS that I was thinking of. To pick the example from the documentation:
> | For example, to allocate 2GB/s limit on the first cache id:
> |    MB:0=2048;1=2048;2=2048;3=2048
> 
> How does user-space know that its not a percentage? Suck it and see...
> If those values aren't in MB/s ... I'm not sure what they are.

I agree that this is an issue.

> 
> 
> The schema format isn't exposed to user-space. (I think we should do that).
> I agree if it were, we'd need to report MBps/MiBps for the mba_sc case.

I agree that it would be ideal to expose the schema format to user space.

>> What is considered
>> here as RESCTRL_SCHEMA_MBPS also cannot really be considered as "MBPS" since it is used to
>> cover AMD's values that are "multiples of one eighth GB/s". Any new resource that
>> _actually_ uses MBPS will thus not be able to use RESCTRL_SCHEMA_MBPS.
> 
> Isn't this already covered by the granularity?
> AMD platforms are unfortunately reporting '1' as the granularity.
>  From the 1/8th GB/s it sounds like the granularity should really be 128 MB/s.

Unfortunately the existing interface makes consistent use of granularity (by user
space) difficult.

As the doc highlights:
	"bandwidth_gran":
		...
		available bandwidth control steps are
		min_bandwidth + N * bandwidth_gran.


You are correct that setting AMD's granularity to 128 MB/s would make the expected
bandwidth clear to user space. The problem is that the existing schemata displays to
user space and expects from user space the value of "N" for MB on AMD while it
displays to user space and expects from user space the value of "min_bandwidth + N *
bandwidth_gran" from user space for MB on Intel.

> 
> Any platform that did have a real MB/s control could report whatever granularity it really
> has here.
> 
> 
>> Considering that RESCTRL_SCHEMA_PERCENTAGE and RESCTRL_SCHEMA_MBPS use the same parser,
>> could "RESCTRL_SCHEMA_RANGE" be more fitting? I acknowledge that it is very generic and
>> better
>> ideas are welcome. A "range" does seem to be appropriate considering the later patch
>> (x86/resctrl:
> 
>> Add max_bw to struct resctrl_membw) that codes an explicit max.
> 
> Yes because the AMD platforms have a firmware-advertised maximum value, I presume that is
> an achievable bandwidth. (otherwise why advertise it to user-space!).
> (I'm not sure why data_width is 4 - it looks like that was the hard coded based on one
>   platforms limit ... that probably needs fixing too)
> 
> But if you had a MBps control, I'm not sure that implies you know what the maximum
> achievable bandwidth is. The control may have a range based on some power of two, which is
> unrelated to the bandwidth.

I believe that is the current resctrl mechanism, with the huge caveat that the only
implementation is actually software defined range limit.

> In the arm world the hardware never knows what the achievable bandwidth is - that is
> something only the SoC designer can work out.
> 
> 
> I agree we can parse both values as a range, as resctrl doesn't need to interpret the
> values, its just whatever the hardware does.
> 
> I did it like this as I'd like to expose "percentage/MBps/bitmap" to user-space so that
> control types user-space doesn't recognised can be programmed. If arm64 and riscv each
> want to add new schema types, it would be good to do it in a way that is low-impact for
> the resctrl filesystem code, and unaware user-space can do something with.
> percentage/MBps/bitmap are the control schemes we already have.

Adding bitmap will need more thought, since resctrl does not support that today for
MB there is some flexibility when adding support for it.

> 
> The MBps/range difference matters if the 'maximum bandwidth' isn't actually an achievable
> number e.g. ~0, then user-space can't treat it as some kind of percentage.

This last statement is not clear to me. It sounds as though you are considering the
underlying implementation treating provided bandwidth as percentage as opposed to
the interface itself being bandwidth or percentage? hmmm ... or are you referring to
the software controller?

I wonder if bandwidth and percentage can continue using the same interface as today
by using bandwidth_gran as you hinted to ... but with the backward compatibility of
needing to distinguish between schemata interface expecting the total or the steps.
I do not know what (if any) impact there will be if AMD's bandwidth_gran is
changed to 128 MB/s.

Reinette

Re: [PATCH v4 08/39] x86/resctrl: Generate default_ctrl instead of sharing it

[Reinette Chatre]

Hi James,

On 9/13/24 11:07 AM, James Morse wrote:
> Hi Reinette,
> 
> On 14/08/2024 05:00, Reinette Chatre wrote:
>> On 8/2/24 10:28 AM, James Morse wrote:
>>
>>> +/**
>>> + * 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_PERCENTAGE:
>>> +        return 100u;
>>> +    case RESCTRL_SCHEMA_MBPS:
>>> +        return r->membw.max_bw;
>>> +    }
>>> +
>>> +    return WARN_ON_ONCE(1);
>>> +}
>>> +
> 
>> I am concerned where this is headed. Since RESCTRL_SCHEMA_PERCENTAGE remains
>> in use when resctrl is mounted with mba_MBps the default cannot always
>> be 100u (it should be MBA_MAX_MBPS when software controller is active).
> 
> I agree - and we can certainly tidy that up.
> But today when mba_sc is enable the bandwidth_gran and min-bandwidth files both report
> '10' (%?), which isn't particularly meaningful.

Indeed. The complication with mba_sc is that it is a user facing MB/s solution implemented
by percentages in hardware.

> I think these should both report '1'. There will be a minimum bandwidth, buts it not
> something that can be discovered by the mba_sc code.

I understand that it may simplify the interface but please take care that the implementation
relies on these values to determine which percentage to use to accomplish a user
requested Mb/s.

> 
> This was an oversight because the mba_sc mode doesn't update default_ctrl or the format
> strings - it hijacks the parsing elsewhere. The default_ctrl isn't visible to user-space,
> the value used when reading the schema file comes from the mbps_val array, instead of
> ctrl_val.

Right.

> 
> 
> Some of this has been booted over the horizon - I'll add straightening out the mba_sc
> behaviour here to that list.

Ack. I think it will be simpler for this work to focus on splitting existing
implementation. If clearing these up are a priority we can also work on it before
the split, but not as part of this change that I believe was intended to not
include functional changes.

Reinette

Re: [PATCH v4 17/39] x86/resctrl: Rewrite and move the for_each_*_rdt_resource() walkers

[James Morse]

Hi Shaopeng Tan,

On 15/08/2024 07:43, Shaopeng Tan (Fujitsu) wrote:
>> Subject: [PATCH v4 17/39] 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 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 the core header so existing x86 arch code continues to use them.

>> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h
>> b/arch/x86/kernel/cpu/resctrl/internal.h
>> index 8e52e81a044b..84e0d019423d 100644
>> --- a/arch/x86/kernel/cpu/resctrl/internal.h
>> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
>> @@ -472,14 +472,6 @@ extern struct rdt_hw_resource rdt_resources_all[];

>> diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index
>> c8cd6dde91ed..04a410a5e739 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)->rid < RDT_NUM_RESOURCES - 1;
>> 		\
>> +	     (_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)
>> +

> ERROR: Macros with complex values should be enclosed in parentheses

This is from checkpatch - I've ignored it because the 'r' values are in parenthesis...

I _think_ what it wants is this:               \|/
| #define for_each_mon_capable_rdt_resource(r)	(	\
|        for_each_rdt_resource((r))			\
|		if ((r)->mon_capable))			\

but then this macro wouldn't work in the way it is intended to be used because it breaks
the deliberately dangling if statement

Checkpatch also complains about the existing code.

I think this is just a pattern of code that is frowned on (including by me!). Previous
versions of this series rolled these out as a loop and condition at each call site, but
Reinette didn't think this was worth the churn as the existing helpers are well understood.


Thanks,

James

Re: [PATCH v4 15/39] x86/resctrl: Move monitor exit work to a resctrl exit call

[James Morse]

Hi Reinette,

On 14/08/2024 05:01, Reinette Chatre wrote:
> On 8/2/24 10:28 AM, James Morse wrote:
>> 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
>> ---
>> 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.
> 
> Is this still relevant? It is unclear to me why __exit is dropped here.

resctrl_init() in the next patch wants to call resctrl_mon_resource_exit() as part of its
cleanup. This trips the mismatched section checks as the __exit code is discarded at link
time because you can't build resctrl as a module.

I'll opt for the churnier version that removes the exit markers in the next patch.


Thanks,

James

Re: [PATCH v4 04/39] x86/resctrl: Use schema type to determine how to parse schema values

[James Morse]

Hi Reinette,

On 16/09/2024 23:33, Reinette Chatre wrote:
> On 9/6/24 11:06 AM, James Morse wrote:
>> On 14/08/2024 04:56, Reinette Chatre wrote:
>>> On 8/2/24 10:28 AM, James Morse wrote:
>>>> diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
>>>> index 9ca542a8e2d4..57c88e1c2adf 100644
>>>> --- a/arch/x86/kernel/cpu/resctrl/core.c
>>>> +++ b/arch/x86/kernel/cpu/resctrl/core.c

>>>> @@ -192,6 +191,18 @@ 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_PERCENTAGE:    The schema is a decimal percentage value.
>>>> + * @RESCTRL_SCHEMA_MBPS:    The schema is a decimal MBps value.
>>>> + */
>>>> +enum resctrl_schema_fmt {
>>>> +    RESCTRL_SCHEMA_BITMAP,
>>>> +    RESCTRL_SCHEMA_PERCENTAGE,
>>>> +    RESCTRL_SCHEMA_MBPS,
>>>> +};
>>>> +
>>>
>>> I believe that the choice of RESCTRL_SCHEMA_PERCENTAGE and RESCTRL_SCHEMA_MBPS has
>>> potential for significant confusion. The closest place to where user space can enter
>>> a MBps value (which is actually MiBps) is on Intel when resctrl is mounted with mba_MBps,
>>> and as per above it will have the "RESCTRL_SCHEMA_PERCENTAGE" format.
>>
>> It was AMD's QOS that I was thinking of. To pick the example from the documentation:
>> | For example, to allocate 2GB/s limit on the first cache id:
>> |    MB:0=2048;1=2048;2=2048;3=2048
>>
>> How does user-space know that its not a percentage? Suck it and see...
>> If those values aren't in MB/s ... I'm not sure what they are.
> 
> I agree that this is an issue.
> 
>>
>>
>> The schema format isn't exposed to user-space. (I think we should do that).
>> I agree if it were, we'd need to report MBps/MiBps for the mba_sc case.
> 
> I agree that it would be ideal to expose the schema format to user space.
> 
>>> What is considered
>>> here as RESCTRL_SCHEMA_MBPS also cannot really be considered as "MBPS" since it is used to
>>> cover AMD's values that are "multiples of one eighth GB/s". Any new resource that
>>> _actually_ uses MBPS will thus not be able to use RESCTRL_SCHEMA_MBPS.
>>
>> Isn't this already covered by the granularity?
>> AMD platforms are unfortunately reporting '1' as the granularity.
>>  From the 1/8th GB/s it sounds like the granularity should really be 128 MB/s.
> 
> Unfortunately the existing interface makes consistent use of granularity (by user
> space) difficult.
> 
> As the doc highlights:
>     "bandwidth_gran":
>         ...
>         available bandwidth control steps are
>         min_bandwidth + N * bandwidth_gran.
> 
> 
> You are correct that setting AMD's granularity to 128 MB/s would make the expected
> bandwidth clear to user space. The problem is that the existing schemata displays to
> user space and expects from user space the value of "N" for MB on AMD while it
> displays to user space and expects from user space the value of "min_bandwidth + N *
> bandwidth_gran" from user space for MB on Intel.

Huh, I missed this in the datasheet:
(p21 of 56375_1_03_PUB.pdf)
| an absolute number expressed in 1/8 GB/s increments

I assumed the value was in MB/s but the precision of existing implementations was 128MB -
meaning they could change the precision without breaking user-space. Oh well.

Fixing this would also break user-space, so I guess this has to count in 'platform' units,
folk will need to know intimate details of their platform to configure this ...

As you suggest, its handled as a 'range' for now, and we can unpick this later.


>> Any platform that did have a real MB/s control could report whatever granularity it really
>> has here.
>>
>>
>>> Considering that RESCTRL_SCHEMA_PERCENTAGE and RESCTRL_SCHEMA_MBPS use the same parser,
>>> could "RESCTRL_SCHEMA_RANGE" be more fitting? I acknowledge that it is very generic and
>>> better
>>> ideas are welcome. A "range" does seem to be appropriate considering the later patch
>>> (x86/resctrl:
>>
>>> Add max_bw to struct resctrl_membw) that codes an explicit max.
>>
>> Yes because the AMD platforms have a firmware-advertised maximum value, I presume that is
>> an achievable bandwidth. (otherwise why advertise it to user-space!).
>> (I'm not sure why data_width is 4 - it looks like that was the hard coded based on one
>>   platforms limit ... that probably needs fixing too)
>>
>> But if you had a MBps control, I'm not sure that implies you know what the maximum
>> achievable bandwidth is. The control may have a range based on some power of two, which is
>> unrelated to the bandwidth.
> 
> I believe that is the current resctrl mechanism, with the huge caveat that the only
> implementation is actually software defined range limit.

True. MPAM doesn't have one - but does allow implementers to add their own scheme. Some of
this is to ensure resctrl doesn't have to know about this, but can also tell user-space
what the configurations mean.


>> In the arm world the hardware never knows what the achievable bandwidth is - that is
>> something only the SoC designer can work out.
>>
>>
>> I agree we can parse both values as a range, as resctrl doesn't need to interpret the
>> values, its just whatever the hardware does.
>>
>> I did it like this as I'd like to expose "percentage/MBps/bitmap" to user-space so that
>> control types user-space doesn't recognised can be programmed. If arm64 and riscv each
>> want to add new schema types, it would be good to do it in a way that is low-impact for
>> the resctrl filesystem code, and unaware user-space can do something with.
>> percentage/MBps/bitmap are the control schemes we already have.
> 
> Adding bitmap will need more thought, since resctrl does not support that today for
> MB there is some flexibility when adding support for it.

True, and architecture shouldn't specify this - and shouldn't expect it to work properly
if it does


>> The MBps/range difference matters if the 'maximum bandwidth' isn't actually an achievable
>> number e.g. ~0, then user-space can't treat it as some kind of percentage.
> 
> This last statement is not clear to me. It sounds as though you are considering the
> underlying implementation treating provided bandwidth as percentage as opposed to
> the interface itself being bandwidth or percentage? hmmm ... or are you referring to
> the software controller?

> I wonder if bandwidth and percentage can continue using the same interface as today
> by using bandwidth_gran as you hinted to ... but with the backward compatibility of
> needing to distinguish between schemata interface expecting the total or the steps.

My thinking was that the architecture should specify MBps or percentage to resctrl - even
if resctrl just treats these are numbers, because the difference matters to user-space.
If user-space doesn't know what an 'SLC' is - but it takes a percentage, then values that
add up to 100% is going to do something meaningful.
If the value is between 0 and ~0 as MBps - user-space needs to be smart enough to know
that numbers that add up to ~0 is unlikely to do what they want....


> I do not know what (if any) impact there will be if AMD's bandwidth_gran is
> changed to 128 MB/s.

I don't think we can do that without regressing existing user-space - the values written
into the schemata file would change their meaning.


Thanks,

James

Re: [PATCH v4 20/39] x86/resctrl: Change mon_event_config_{read,write}() to be arch helpers

[James Morse]

Hi Reinette,

On 14/08/2024 05:02, Reinette Chatre wrote:
> On 8/2/24 10:28 AM, James Morse wrote:
>> @@ -1617,14 +1612,15 @@ static void mon_event_config_read(void *info)
>>       mon_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 = {0};
>> +    struct resctrl_mon_config_info mon_info = {0};
>>       struct rdt_mon_domain *dom;
>>       bool sep = false;
>>   
> 
> Patch looks good, just a fyi:
> https://lore.kernel.org/lkml/b2ebc809c8b6c6440d17b12ccf7c2d29aaafd488.1720868538.git.christophe.jaillet@wanadoo.fr

Right - I'll pick that as prerequisite so that it rebases out neatly.


Thanks,

James

Re: [PATCH v4 00/39] x86/resctrl: Move the resctrl filesystem code to /fs/resctrl

[James Morse]

Hello!

On 15/08/2024 08:04, Shaopeng Tan (Fujitsu) wrote:
> I have no other problems with this series.
> reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>

Great - thanks!

James