[PATCH v5 02/44] perf: Add generic exclude_guest support

Sean Christopherson
2025-08-06T19:57:32Z

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

Only KVM knows the exact time when a guest is entering/exiting. Expose
two interfaces to KVM to switch the ownership of the PMU resources.

All the pinned events must be scheduled in first. Extend the
perf_event_sched_in() helper to support extra flag, e.g., EVENT_GUEST.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Mingwei Zhang <mizhang@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
kernel/events/core.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index d4528554528d..3a98e11d8efc 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -2866,14 +2866,15 @@ static void task_ctx_sched_out(struct perf_event_context *ctx,

static void perf_event_sched_in(struct perf_cpu_context *cpuctx,
struct perf_event_context *ctx,
- struct pmu *pmu)
+ struct pmu *pmu,
+ enum event_type_t event_type)
{
- ctx_sched_in(&cpuctx->ctx, pmu, EVENT_PINNED);
+ ctx_sched_in(&cpuctx->ctx, pmu, EVENT_PINNED | event_type);
if (ctx)
- ctx_sched_in(ctx, pmu, EVENT_PINNED);
- ctx_sched_in(&cpuctx->ctx, pmu, EVENT_FLEXIBLE);
+ ctx_sched_in(ctx, pmu, EVENT_PINNED | event_type);
+ ctx_sched_in(&cpuctx->ctx, pmu, EVENT_FLEXIBLE | event_type);
if (ctx)
- ctx_sched_in(ctx, pmu, EVENT_FLEXIBLE);
+ ctx_sched_in(ctx, pmu, EVENT_FLEXIBLE | event_type);
}

/*
@@ -2929,7 +2930,7 @@ static void ctx_resched(struct perf_cpu_context *cpuctx,
else if (event_type & EVENT_PINNED)
ctx_sched_out(&cpuctx->ctx, pmu, EVENT_FLEXIBLE);

- perf_event_sched_in(cpuctx, task_ctx, pmu);
+ perf_event_sched_in(cpuctx, task_ctx, pmu, 0);

for_each_epc(epc, &cpuctx->ctx, pmu, 0)
perf_pmu_enable(epc->pmu);
@@ -4147,7 +4148,7 @@ static void perf_event_context_sched_in(struct task_struct *task)
ctx_sched_out(&cpuctx->ctx, NULL, EVENT_FLEXIBLE);
}

- perf_event_sched_in(cpuctx, ctx, NULL);
+ perf_event_sched_in(cpuctx, ctx, NULL, 0);

perf_ctx_sched_task_cb(cpuctx->task_ctx, task, true);

--
2.50.1.565.gc32cd1483b-goog