Commit 89cb454e authored by Like Xu's avatar Like Xu Committed by Paolo Bonzini
Browse files

KVM: x86/pmu: Extract check_pmu_event_filter() handling both GP and fixed counters 



Checking the kvm->arch.pmu_event_filter policy in both gp and fixed
code paths was somewhat redundant, so common parts can be extracted,
which reduces code footprint and improves readability.

Signed-off-by: default avatarLike Xu <likexu@tencent.com>
Reviewed-by: default avatarWanpeng Li <wanpengli@tencent.com>
Message-Id: <20220518132512.37864-3-likexu@tencent.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent a33095f4

arch/x86/kvm/pmu.c

+37 −26
Original line number Diff line number Diff line
@@ -250,14 +250,44 @@ static int cmp_u64(const void *pa, const void *pb) 
	return (a > b) - (a < b);

}



static bool check_pmu_event_filter(struct kvm_pmc *pmc)

{

	struct kvm_pmu_event_filter *filter;

	struct kvm *kvm = pmc->vcpu->kvm;

	bool allow_event = true;

	__u64 key;

	int idx;



	filter = srcu_dereference(kvm->arch.pmu_event_filter, &kvm->srcu);

	if (!filter)

		goto out;



	if (pmc_is_gp(pmc)) {

		key = pmc->eventsel & AMD64_RAW_EVENT_MASK_NB;

		if (bsearch(&key, filter->events, filter->nevents,

			    sizeof(__u64), cmp_u64))

			allow_event = filter->action == KVM_PMU_EVENT_ALLOW;

		else

			allow_event = filter->action == KVM_PMU_EVENT_DENY;

	} else {

		idx = pmc->idx - INTEL_PMC_IDX_FIXED;

		if (filter->action == KVM_PMU_EVENT_DENY &&

		    test_bit(idx, (ulong *)&filter->fixed_counter_bitmap))

			allow_event = false;

		if (filter->action == KVM_PMU_EVENT_ALLOW &&

		    !test_bit(idx, (ulong *)&filter->fixed_counter_bitmap))

			allow_event = false;

	}



out:

	return allow_event;

}



void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)

{

	u64 config;

	u32 type = PERF_TYPE_RAW;

	struct kvm *kvm = pmc->vcpu->kvm;

	struct kvm_pmu_event_filter *filter;

	struct kvm_pmu *pmu = vcpu_to_pmu(pmc->vcpu);

	bool allow_event = true;

	struct kvm_pmu *pmu = pmc_to_pmu(pmc);



	if (eventsel & ARCH_PERFMON_EVENTSEL_PIN_CONTROL)

		printk_once("kvm pmu: pin control bit is ignored\n");
@@ -269,17 +299,7 @@ void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel) 
	if (!(eventsel & ARCH_PERFMON_EVENTSEL_ENABLE) || !pmc_is_enabled(pmc))

		return;



	filter = srcu_dereference(kvm->arch.pmu_event_filter, &kvm->srcu);

	if (filter) {

		__u64 key = eventsel & AMD64_RAW_EVENT_MASK_NB;



		if (bsearch(&key, filter->events, filter->nevents,

			    sizeof(__u64), cmp_u64))

			allow_event = filter->action == KVM_PMU_EVENT_ALLOW;

		else

			allow_event = filter->action == KVM_PMU_EVENT_DENY;

	}

	if (!allow_event)

	if (!check_pmu_event_filter(pmc))

		return;



	if (!(eventsel & (ARCH_PERFMON_EVENTSEL_EDGE |
@@ -312,23 +332,14 @@ void reprogram_fixed_counter(struct kvm_pmc *pmc, u8 ctrl, int idx) 
{

	unsigned en_field = ctrl & 0x3;

	bool pmi = ctrl & 0x8;

	struct kvm_pmu_event_filter *filter;

	struct kvm *kvm = pmc->vcpu->kvm;



	pmc_pause_counter(pmc);



	if (!en_field || !pmc_is_enabled(pmc))

		return;



	filter = srcu_dereference(kvm->arch.pmu_event_filter, &kvm->srcu);

	if (filter) {

		if (filter->action == KVM_PMU_EVENT_DENY &&

		    test_bit(idx, (ulong *)&filter->fixed_counter_bitmap))

	if (!check_pmu_event_filter(pmc))

		return;

		if (filter->action == KVM_PMU_EVENT_ALLOW &&

		    !test_bit(idx, (ulong *)&filter->fixed_counter_bitmap))

			return;

	}



	if (pmc->current_config == (u64)ctrl && pmc_resume_counter(pmc))

		return;