[PATCH v2 14/54] perf: core/x86: Plumb passthrough PMU capability from x86_pmu to x86_pmu_cap

Mingwei Zhang
2024-05-06T05:30:53Z

Plumb passthrough PMU capability to x86_pmu_cap in order to let any kernel
entity such as KVM know that host PMU support passthrough PMU mode and has
the implementation.

Signed-off-by: Mingwei Zhang <mizhang@google.com>
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
---
arch/x86/events/core.c | 1 +
arch/x86/events/intel/core.c | 1 +
arch/x86/events/perf_event.h | 1 +
arch/x86/include/asm/perf_event.h | 1 +
4 files changed, 4 insertions(+)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index c0f6e294fcad..f5a043410614 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -3023,6 +3023,7 @@ void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
cap->events_mask = (unsigned int)x86_pmu.events_maskl;
cap->events_mask_len = x86_pmu.events_mask_len;
cap->pebs_ept = x86_pmu.pebs_ept;
+ cap->passthrough = !!(x86_pmu.flags & PMU_FL_PASSTHROUGH);
}
EXPORT_SYMBOL_GPL(perf_get_x86_pmu_capability);

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 4d8f907a9416..62d327cb5424 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -6246,6 +6246,7 @@ __init int intel_pmu_init(void)

/* The perf side of core PMU is ready to support the passthrough vPMU. */
x86_get_pmu(smp_processor_id())->capabilities |= PERF_PMU_CAP_PASSTHROUGH_VPMU;
+ x86_pmu.flags |= PMU_FL_PASSTHROUGH;

/*
* Install the hw-cache-events table:
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index fb56518356ec..bdf6d114d05a 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -1020,6 +1020,7 @@ do { \
#define PMU_FL_MEM_LOADS_AUX 0x100 /* Require an auxiliary event for the complete memory info */
#define PMU_FL_RETIRE_LATENCY 0x200 /* Support Retire Latency in PEBS */
#define PMU_FL_BR_CNTR 0x400 /* Support branch counter logging */
+#define PMU_FL_PASSTHROUGH 0x800 /* Support passthrough mode */

#define EVENT_VAR(_id) event_attr_##_id
#define EVENT_PTR(_id) &event_attr_##_id.attr.attr
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index 807ea9c98567..39a6379162bc 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -258,6 +258,7 @@ struct x86_pmu_capability {
unsigned int events_mask;
int events_mask_len;
unsigned int pebs_ept :1;
+ unsigned int passthrough :1;
};

/*
--
2.45.0.rc1.225.g2a3ae87e7f-goog