Commit 5421db1b authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: Divorce the perf code from oprofile helpers 



KVM/arm64 is the sole user of perf_num_counters(), and really
could do without it. Stop using the obsolete API by relying on
the existing probing code.

Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Acked-by: default avatarWill Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210414134409.1266357-2-maz@kernel.org
parent 1e28eed1

arch/arm64/kvm/perf.c

+1 −6
Original line number Diff line number Diff line
@@ -50,12 +50,7 @@ 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)

	if (kvm_pmu_probe_pmuver() != 0xf)

		static_branch_enable(&kvm_arm_pmu_available);



	return perf_register_guest_info_callbacks(&kvm_guest_cbs);

arch/arm64/kvm/pmu-emul.c

+1 −1
Original line number Diff line number Diff line
@@ -739,7 +739,7 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, 
	kvm_pmu_create_perf_event(vcpu, select_idx);

}



static int kvm_pmu_probe_pmuver(void)

int kvm_pmu_probe_pmuver(void)

{

	struct perf_event_attr attr = { };

	struct perf_event *event;

include/kvm/arm_pmu.h

+4 −0
Original line number Diff line number Diff line
@@ -61,6 +61,7 @@ int kvm_arm_pmu_v3_get_attr(struct kvm_vcpu *vcpu, 
int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu,

			    struct kvm_device_attr *attr);

int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu);

int kvm_pmu_probe_pmuver(void);

#else

struct kvm_pmu {

};
@@ -116,6 +117,9 @@ static inline u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) 
{

	return 0;

}



static inline int kvm_pmu_probe_pmuver(void) { return 0xf; }



#endif



#endif