[PATCH V2 5/9] perf/x86/intel: Support Architectural PerfMon Extension leaf

kan.liang
2023-01-04T20:14:32Z

From: Kan Liang <kan.liang@linux.intel.com>

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>
---

No change since V1

arch/x86/events/intel/core.c | 22 ++++++++++++++++++++++
arch/x86/include/asm/perf_event.h | 8 ++++++++
2 files changed, 30 insertions(+)

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index a5678ab6d3e3..29d2d0411caf 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -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;

diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index 5d0f6891ae61..6496bdbcac98 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -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:
*/
--
2.35.1