KVM: x86/mmu: Move fast_page_fault() call above mmu_topup_memory_caches() (83291445) · Commits · 戴 / test

Avoid refilling the memory caches and potentially slow reclaim/swap when handling a fast page fault, which does not need to allocate any new objects. Reviewed-by:

Ben Gardon <bgardon@google.com> Signed-off-by:

Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200703023545.8771-7-sean.j.christopherson@intel.com> Signed-off-by:

Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/mmu/mmu.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -4120,6 +4120,9 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
		if (page_fault_handle_page_track(vcpu, error_code, gfn))
		return RET_PF_EMULATE;

		if (fast_page_fault(vcpu, gpa, error_code))
		return RET_PF_RETRY;

		r = mmu_topup_memory_caches(vcpu);
		if (r)
		return r;
		@@ -4127,9 +4130,6 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
		if (lpage_disallowed)
		max_level = PG_LEVEL_4K;

		if (fast_page_fault(vcpu, gpa, error_code))
		return RET_PF_RETRY;

		mmu_seq = vcpu->kvm->mmu_notifier_seq;
		smp_rmb();

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