[tip: perf/core] perf/x86/intel: Support Architectural PerfMon Extension leaf

tip-bot2 for Kan Liang
2023-01-09T17:03:04Z

The following commit has been merged into the perf/core branch of tip:

Commit-ID: eb467aaac21e133a3d01c48c0a6bf43756b06e78
Gitweb: https://git.kernel.org/tip/eb467aaac21e133a3d01c48c0a6bf43756b06e78
Author: Kan Liang <kan.liang@linux.intel.com>
AuthorDate: Wed, 04 Jan 2023 12:13:45 -08:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Mon, 09 Jan 2023 12:22:08 +01:00

perf/x86/intel: Support Architectural PerfMon Extension leaf

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
---
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 a5678ab..29d2d04 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 5d0f689..6496bdb 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -160,6 +160,14 @@ union cpuid10_edx {
};

/*
+ * 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:
*/
union cpuid28_eax {