diff mbox series

[v2,43/43] KVM: VMX: Don't do full kick when handling posted interrupt wakeup

Message ID 20211009021236.4122790-44-seanjc@google.com (mailing list archive)
State New, archived
Headers show
Series KVM: Halt-polling and x86 APICv overhaul | expand

Commit Message

Sean Christopherson Oct. 9, 2021, 2:12 a.m. UTC 
When waking vCPUs in the posted interrupt wakeup handling, do exactly
that and no more.  There is no need to kick the vCPU as the wakeup
handler just need to get the vCPU task running, and if it's in the guest
then it's definitely running.

Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/vmx/posted_intr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Paolo Bonzini Oct. 25, 2021, 2:16 p.m. UTC | #1 
On 09/10/21 04:12, Sean Christopherson wrote:
> When waking vCPUs in the posted interrupt wakeup handling, do exactly
> that and no more.  There is no need to kick the vCPU as the wakeup
> handler just need to get the vCPU task running, and if it's in the guest
> then it's definitely running.

And more important, the transition from blocking to running will have 
gone through sync_pir_to_irr, thus checking ON and manually moving the 
vector from PIR to RVI.

Paolo
Maxim Levitsky Oct. 31, 2021, 10:33 p.m. UTC | #2 
On Mon, 2021-10-25 at 16:16 +0200, Paolo Bonzini wrote:
> On 09/10/21 04:12, Sean Christopherson wrote:
> > When waking vCPUs in the posted interrupt wakeup handling, do exactly
> > that and no more.  There is no need to kick the vCPU as the wakeup
> > handler just need to get the vCPU task running, and if it's in the guest
> > then it's definitely running.
> 
> And more important, the transition from blocking to running will have 
> gone through sync_pir_to_irr, thus checking ON and manually moving the 
> vector from PIR to RVI.
> 
> Paolo
> 
I also think so, and maybe this can be added to the commit message.

Anyway, last one for the series :)

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>



Best regards,
	Maxim Levitsky
diff mbox series

Patch

diff --git a/arch/x86/kvm/vmx/posted_intr.c b/arch/x86/kvm/vmx/posted_intr.c
index f1bcf8c32b6d..06eb9c950760 100644
--- a/arch/x86/kvm/vmx/posted_intr.c
+++ b/arch/x86/kvm/vmx/posted_intr.c
@@ -192,7 +192,7 @@  void pi_wakeup_handler(void)
 			    pi_wakeup_list) {
 
 		if (pi_test_on(&vmx->pi_desc))
-			kvm_vcpu_kick(&vmx->vcpu);
+			kvm_vcpu_wake_up(&vmx->vcpu);
 	}
 	spin_unlock(&per_cpu(wakeup_vcpus_on_cpu_lock, cpu));
 }