x86/resctrl: Add resctrl_arch_is_evt_configurable() to abstract BMEC

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

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

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

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

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Fenghua Yu <fenghuay@nvidia.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
Tested-by: Peter Newman <peternewman@google.com>
Tested-by: Amit Singh Tomar <amitsinght@marvell.com> # arm64
Tested-by: Shanker Donthineni <sdonthineni@nvidia.com> # arm64
Tested-by: Babu Moger <babu.moger@amd.com>
Link: https://lore.kernel.org/r/20250311183715.16445-20-james.morse@arm.com

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index eba210db4a7bd87a5f4fc2090097451a2ff1a2e9..6f0d1bbba901946b8166602b0d983bc18150e14f 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -830,6 +830,21 @@ bool __init rdt_cpu_has(int flag)
        return ret;
 }
 
+__init bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt)
+{
+       if (!rdt_cpu_has(X86_FEATURE_BMEC))
+               return false;
+
+       switch (evt) {
+       case QOS_L3_MBM_TOTAL_EVENT_ID:
+               return rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL);
+       case QOS_L3_MBM_LOCAL_EVENT_ID:
+               return rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL);
+       default:
+               return false;
+       }
+}
+
 static __init bool get_mem_config(void)
 {
        struct rdt_hw_resource *hw_res = &rdt_resources_all[RDT_RESOURCE_MBA];

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index d883ed56ec907e962009215ed213b722c2d8c35a..27d983121b0a5dd129f10cadadeaeaff16a77b52 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -1202,6 +1202,17 @@ int __init resctrl_mon_resource_init(void)
 
        l3_mon_evt_init(r);
 
+       if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_TOTAL_EVENT_ID)) {
+               mbm_total_event.configurable = true;
+               resctrl_file_fflags_init("mbm_total_bytes_config",
+                                        RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
+       }
+       if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_LOCAL_EVENT_ID)) {
+               mbm_local_event.configurable = true;
+               resctrl_file_fflags_init("mbm_local_bytes_config",
+                                        RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
+       }
+
        return 0;
 }
 
@@ -1245,17 +1256,6 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
                /* Detect list of bandwidth sources that can be tracked */
                cpuid_count(0x80000020, 3, &eax, &ebx, &ecx, &edx);
                hw_res->mbm_cfg_mask = ecx & MAX_EVT_CONFIG_BITS;
-
-               if (rdt_cpu_has(X86_FEATURE_CQM_MBM_TOTAL)) {
-                       mbm_total_event.configurable = true;
-                       resctrl_file_fflags_init("mbm_total_bytes_config",
-                                                RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
-               }
-               if (rdt_cpu_has(X86_FEATURE_CQM_MBM_LOCAL)) {
-                       mbm_local_event.configurable = true;
-                       resctrl_file_fflags_init("mbm_local_bytes_config",
-                                                RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
-               }
        }
 
        r->mon_capable = true;

diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
index a392480dc4b63a9442e5ebdeaed544330b4374a5..cc76f308e6f38c37f893e62de99fa79d41079267 100644 (file)
--- a/include/linux/resctrl.h
+++ b/include/linux/resctrl.h
@@ -309,6 +309,8 @@ u32 resctrl_arch_get_num_closid(struct rdt_resource *r);
 u32 resctrl_arch_system_num_rmid_idx(void);
 int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
 
+__init bool resctrl_arch_is_evt_configurable(enum resctrl_event_id evt);
+
 /*
  * Update the ctrl_val and apply this config right now.
  * Must be called on one of the domain's CPUs.