[RFC PATCH 06/41] perf: x86: Add function to switch PMI handler

[Xiong Zhang]

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

Add function to switch PMI handler since passthrough PMU and host PMU will
use different interrupt vectors.

Signed-off-by: Xiong Zhang <xiong.y.zhang@xxxxxxxxx>
Signed-off-by: Mingwei Zhang <mizhang@xxxxxxxxxx>
---
 arch/x86/events/core.c            | 15 +++++++++++++++
 arch/x86/include/asm/perf_event.h |  3 +++
 2 files changed, 18 insertions(+)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 40ad1425ffa2..3f87894d8c8e 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -701,6 +701,21 @@ struct perf_guest_switch_msr *perf_guest_get_msrs(int *nr, void *data)
 }
 EXPORT_SYMBOL_GPL(perf_guest_get_msrs);
 
+void perf_guest_switch_to_host_pmi_vector(void)
+{
+	lockdep_assert_irqs_disabled();
+
+	apic_write(APIC_LVTPC, APIC_DM_NMI);
+}
+EXPORT_SYMBOL_GPL(perf_guest_switch_to_host_pmi_vector);
+
+void perf_guest_switch_to_kvm_pmi_vector(void)
+{
+	lockdep_assert_irqs_disabled();
+
+	apic_write(APIC_LVTPC, APIC_DM_FIXED | KVM_VPMU_VECTOR);
+}
+EXPORT_SYMBOL_GPL(perf_guest_switch_to_kvm_pmi_vector);
 /*
  * There may be PMI landing after enabled=0. The PMI hitting could be before or
  * after disable_all.
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index 2618ec7c3d1d..021ab362a061 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -573,6 +573,9 @@ static inline void perf_events_lapic_init(void)	{ }
 static inline void perf_check_microcode(void) { }
 #endif
 
+extern void perf_guest_switch_to_host_pmi_vector(void);
+extern void perf_guest_switch_to_kvm_pmi_vector(void);
+
 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
 extern struct perf_guest_switch_msr *perf_guest_get_msrs(int *nr, void *data);
 extern void x86_perf_get_lbr(struct x86_pmu_lbr *lbr);
-- 
2.34.1