[PATCH v1 15/31] x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC

James Morse
2024-03-21T16:52:18Z

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>
---
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 a4b5ade6e291..824a94593e9d 100644
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -667,7 +667,7 @@ 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),
@@ -707,7 +707,7 @@ 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;
@@ -727,6 +727,21 @@ 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 edbccc79246f..46370eafb00f 100644
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -507,7 +507,7 @@ int alloc_rmid(u32 closid);
void free_rmid(u32 closid, u32 rmid);
int rdt_get_mon_l3_config(struct rdt_resource *r);
void __exit resctrl_mon_resource_exit(void);
-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,
@@ -527,7 +527,7 @@ bool has_busy_rmid(struct rdt_domain *d);
void __check_limbo(struct rdt_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 c9be2d0819c0..ccb85c61b43b 100644
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1019,6 +1019,15 @@ int 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;
}

@@ -1060,15 +1069,6 @@ 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 8285b916289c..2d6f4e0d3656 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2068,7 +2068,7 @@ 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 b0ee7256e095..bfc63e8219e5 100644
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -204,6 +204,8 @@ u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
struct rdt_domain *resctrl_arch_find_domain(struct rdt_resource *r, 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