[RFC,10/41] perf: core/x86: Plumb passthrough PMU capability from x86_pmu to x86_pmu_cap

Commit Message

Xiong Zhang Jan. 26, 2024, 8:54 a.m. UTC

From: Mingwei Zhang <[e-mail]>

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 <[e-mail]>
---
 arch/x86/events/core.c            | 1 +
 arch/x86/events/intel/core.c      | 4 +++-
 arch/x86/events/perf_event.h      | 1 +
 arch/x86/include/asm/perf_event.h | 1 +
 4 files changed, 6 insertions(+), 1 deletion(-)

Patch

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 20a5ccc641b9..d2b7aa5b7876 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -3026,6 +3026,7 @@  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 cf790c37757a..727ee64bb566 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -6140,8 +6140,10 @@  __init int intel_pmu_init(void)
 			pr_cont(" AnyThread deprecated, ");
 	}
 
-	if (version >= 4)
+	if (version >= 4) {
+		x86_pmu.flags |= PMU_FL_PASSTHROUGH;
 		x86_get_pmu(smp_processor_id())->capabilities |= PERF_PMU_CAP_VPMU_PASSTHROUGH;
+	}
 
 	/*
 	 * Install the hw-cache-events table:
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index 53dd5d495ba6..39c58a3f5a6b 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -1012,6 +1012,7 @@  do {									\
 #define PMU_FL_INSTR_LATENCY	0x80 /* Support Instruction Latency in PEBS Memory Info Record */
 #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_PASSTHROUGH	0x400 /* 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 180d63ba2f46..400727b27634 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -254,6 +254,7 @@  struct x86_pmu_capability {
 	unsigned int	events_mask;
 	int		events_mask_len;
 	unsigned int	pebs_ept	:1;
+	unsigned int	passthrough	:1;
 };
 
 /*