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-rw-r--r--arch/arm64/kvm/perf.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/arm64/kvm/perf.c b/arch/arm64/kvm/perf.c
index d45b8b9a4415..739164324afe 100644
--- a/arch/arm64/kvm/perf.c
+++ b/arch/arm64/kvm/perf.c
@@ -11,6 +11,8 @@
#include <asm/kvm_emulate.h>
+DEFINE_STATIC_KEY_FALSE(kvm_arm_pmu_available);
+
static int kvm_is_in_guest(void)
{
return kvm_get_running_vcpu() != NULL;
@@ -48,6 +50,14 @@ static struct perf_guest_info_callbacks kvm_guest_cbs = {
int kvm_perf_init(void)
{
+ /*
+ * Check if HW_PERF_EVENTS are supported by checking the number of
+ * hardware performance counters. This could ensure the presence of
+ * a physical PMU and CONFIG_PERF_EVENT is selected.
+ */
+ if (IS_ENABLED(CONFIG_ARM_PMU) && perf_num_counters() > 0)
+ static_branch_enable(&kvm_arm_pmu_available);
+
return perf_register_guest_info_callbacks(&kvm_guest_cbs);
}