Commit c5a287fa authored by Aaron Lewis's avatar Aaron Lewis Committed by Sean Christopherson
Browse files

KVM: x86/pmu: prepare the pmu event filter for masked events 



Refactor check_pmu_event_filter() in preparation for masked events.

No functional changes intended

Signed-off-by: default avatarAaron Lewis <aaronlewis@google.com>
Link: https://lore.kernel.org/r/20221220161236.555143-4-aaronlewis@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 8589827f

arch/x86/kvm/pmu.c

+33 −23
Original line number Diff line number Diff line
@@ -263,41 +263,51 @@ static int cmp_u64(const void *pa, const void *pb) 
	return (a > b) - (a < b);

}



static u64 *find_filter_entry(struct kvm_pmu_event_filter *filter, u64 key)

{

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

		       sizeof(filter->events[0]), cmp_u64);

}



static bool is_gp_event_allowed(struct kvm_pmu_event_filter *filter, u64 eventsel)

{

	if (find_filter_entry(filter, eventsel & (kvm_pmu_ops.EVENTSEL_EVENT |

						  ARCH_PERFMON_EVENTSEL_UMASK)))

		return filter->action == KVM_PMU_EVENT_ALLOW;



	return filter->action == KVM_PMU_EVENT_DENY;

}



static bool is_fixed_event_allowed(struct kvm_pmu_event_filter *filter, int idx)

{

	int fixed_idx = idx - INTEL_PMC_IDX_FIXED;



	if (filter->action == KVM_PMU_EVENT_DENY &&

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

		return false;

	if (filter->action == KVM_PMU_EVENT_ALLOW &&

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

		return false;



	return true;

}



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;



	if (!static_call(kvm_x86_pmu_hw_event_available)(pmc))

		return false;



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

	if (!filter)

		goto out;

		return true;



	if (pmc_is_gp(pmc)) {

		key = pmc->eventsel & (kvm_pmu_ops.EVENTSEL_EVENT |

				       ARCH_PERFMON_EVENTSEL_UMASK);

		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;

	}

	if (pmc_is_gp(pmc))

		return is_gp_event_allowed(filter, pmc->eventsel);



out:

	return allow_event;

	return is_fixed_event_allowed(filter, pmc->idx);

}



static void reprogram_counter(struct kvm_pmc *pmc)