[PATCH v4 10/38] perf/x86: Support switch_guest_ctx interface

[Mingwei Zhang]

From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

Implement switch_guest_ctx interface for x86 PMU, switch PMI to dedicated
KVM_GUEST_PMI_VECTOR at perf guest enter, and switch PMI back to
NMI at perf guest exit.

Signed-off-by: Xiong Zhang <xiong.y.zhang@xxxxxxxxxxxxxxx>
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Tested-by: Yongwei Ma <yongwei.ma@xxxxxxxxx>
Signed-off-by: Mingwei Zhang <mizhang@xxxxxxxxxx>
---
 arch/x86/events/core.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 8f218ac0d445..28161d6ff26d 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2677,6 +2677,16 @@ static bool x86_pmu_filter(struct pmu *pmu, int cpu)
 	return ret;
 }
 
+static void x86_pmu_switch_guest_ctx(bool enter, void *data)
+{
+	u32 guest_lvtpc = *(u32 *)data;
+
+	if (enter)
+		apic_write(APIC_LVTPC, guest_lvtpc);
+	else
+		apic_write(APIC_LVTPC, APIC_DM_NMI);
+}
+
 static struct pmu pmu = {
 	.pmu_enable		= x86_pmu_enable,
 	.pmu_disable		= x86_pmu_disable,
@@ -2706,6 +2716,8 @@ static struct pmu pmu = {
 	.aux_output_match	= x86_pmu_aux_output_match,
 
 	.filter			= x86_pmu_filter,
+
+	.switch_guest_ctx	= x86_pmu_switch_guest_ctx,
 };
 
 void arch_perf_update_userpage(struct perf_event *event,
-- 
2.49.0.395.g12beb8f557-goog