From e6d53e3b0db7ae3641f01a2b2af1470fda86d10c Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Mon, 1 Nov 2010 17:01:28 +0800 Subject: [PATCH] KVM: avoid unnecessary wait for a async pf In current code, it checks async pf completion out of the wait context, like this: if (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE && !vcpu->arch.apf.halted) r = vcpu_enter_guest(vcpu); else { ...... kvm_vcpu_block(vcpu) ^- waiting until 'async_pf.done' is not empty } kvm_check_async_pf_completion(vcpu) ^- delete list from async_pf.done So, if we check aysnc pf completion first, it can be blocked at kvm_vcpu_block Fixed by mark the vcpu is unhalted in kvm_check_async_pf_completion() path Signed-off-by: Xiao Guangrong Acked-by: Gleb Natapov Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/x86.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ab10a6ca1549..5daead833669 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6283,6 +6283,7 @@ void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, vcpu->arch.fault.address = work->arch.token; kvm_inject_page_fault(vcpu); } + vcpu->arch.apf.halted = false; } bool kvm_arch_can_inject_async_page_present(struct kvm_vcpu *vcpu) -- GitLab