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perf/x86/intel: Support Architectural PerfMon Extension leaf

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The new CPUID leaf 0x23 reports the "true view" of PMU resources.

The sub-leaf 1 reports the available general-purpose counters and fixed
counters. Update the number of counters and fixed counters when the
sub-leaf is detected.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230104201349.1451191-5-kan.liang@linux.intel.com
This commit is contained in:
Kan Liang 2023-01-04 12:13:45 -08:00 committed by Ingo Molnar
parent a018d2e3d4
commit eb467aaac2
2 changed files with 30 additions and 0 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

22
arch/x86/events/intel/core.c
View file

@ -4588,6 +4588,25 @@ static void flip_smm_bit(void *data)
}
}
static void intel_pmu_check_num_counters(int *num_counters,
int *num_counters_fixed,
u64 *intel_ctrl, u64 fixed_mask);
static void update_pmu_cap(struct x86_hybrid_pmu *pmu)
{
unsigned int sub_bitmaps = cpuid_eax(ARCH_PERFMON_EXT_LEAF);
unsigned int eax, ebx, ecx, edx;
if (sub_bitmaps & ARCH_PERFMON_NUM_COUNTER_LEAF_BIT) {
cpuid_count(ARCH_PERFMON_EXT_LEAF, ARCH_PERFMON_NUM_COUNTER_LEAF,
&eax, &ebx, &ecx, &edx);
pmu->num_counters = fls(eax);
pmu->num_counters_fixed = fls(ebx);
intel_pmu_check_num_counters(&pmu->num_counters, &pmu->num_counters_fixed,
&pmu->intel_ctrl, ebx);
}
}
static bool init_hybrid_pmu(int cpu)
{
struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
@ -4613,6 +4632,9 @@ static bool init_hybrid_pmu(int cpu)
if (!cpumask_empty(&pmu->supported_cpus))
goto end;
if (this_cpu_has(X86_FEATURE_ARCH_PERFMON_EXT))
update_pmu_cap(pmu);
if (!check_hw_exists(&pmu->pmu, pmu->num_counters, pmu->num_counters_fixed))
return false;

8
arch/x86/include/asm/perf_event.h
View file

@ -159,6 +159,14 @@ union cpuid10_edx {
unsigned int full;
};
/*
* Intel "Architectural Performance Monitoring extension" CPUID
* detection/enumeration details:
*/
#define ARCH_PERFMON_EXT_LEAF 0x00000023
#define ARCH_PERFMON_NUM_COUNTER_LEAF_BIT 0x1
#define ARCH_PERFMON_NUM_COUNTER_LEAF 0x1
/*
* Intel Architectural LBR CPUID detection/enumeration details:
*/