[RFC PATCH 31/41] KVM: x86/pmu: Call perf_guest_enter() at PMU context switch

From: Xiong Zhang
Date: Fri Jan 26 2024 - 04:45:01 EST


From: Xiong Zhang <xiong.y.zhang@xxxxxxxxx>

perf subsystem should stop and restart all the perf events at the host
level when entering and leaving the passthrough PMU respectively. So invoke
the perf API at PMU context switch functions.

Signed-off-by: Xiong Zhang <xiong.y.zhang@xxxxxxxxx>
Signed-off-by: Mingwei Zhang <mizhang@xxxxxxxxxx>
---
arch/x86/kvm/pmu.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index cd559fd74f65..afc9f7eb3a6b 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -906,12 +906,16 @@ void kvm_pmu_save_pmu_context(struct kvm_vcpu *vcpu)
static_call_cond(kvm_x86_pmu_save_pmu_context)(vcpu);

perf_guest_switch_to_host_pmi_vector();
+
+ perf_guest_exit();
}

void kvm_pmu_restore_pmu_context(struct kvm_vcpu *vcpu)
{
lockdep_assert_irqs_disabled();

+ perf_guest_enter();
+
perf_guest_switch_to_kvm_pmi_vector(kvm_lapic_get_lvtpc_mask(vcpu));

static_call_cond(kvm_x86_pmu_restore_pmu_context)(vcpu);
--
2.34.1