KVM: VMX: Add support for guest/host-only profiling
Support guest/host-only profiling by switch perf msrs on
a guest entry if needed.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 55e849b..98f4b0b 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -39,6 +39,7 @@
#include <asm/mce.h>
#include <asm/i387.h>
#include <asm/xcr.h>
+#include <asm/perf_event.h>
#include "trace.h"
@@ -6050,6 +6051,24 @@
vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, 0);
}
+static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx)
+{
+ int i, nr_msrs;
+ struct perf_guest_switch_msr *msrs;
+
+ msrs = perf_guest_get_msrs(&nr_msrs);
+
+ if (!msrs)
+ return;
+
+ for (i = 0; i < nr_msrs; i++)
+ if (msrs[i].host == msrs[i].guest)
+ clear_atomic_switch_msr(vmx, msrs[i].msr);
+ else
+ add_atomic_switch_msr(vmx, msrs[i].msr, msrs[i].guest,
+ msrs[i].host);
+}
+
#ifdef CONFIG_X86_64
#define R "r"
#define Q "q"
@@ -6099,6 +6118,8 @@
if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
vmx_set_interrupt_shadow(vcpu, 0);
+ atomic_switch_perf_msrs(vmx);
+
vmx->__launched = vmx->loaded_vmcs->launched;
asm(
/* Store host registers */