Re: [PATCH] KVM: LAPIC: Don't kick vCPU which is injecting already-expired timer

2020-08-23 Thread Wanpeng Li
On Sat, 22 Aug 2020 at 12:01, Sean Christopherson wrote: > > On Fri, Aug 21, 2020 at 05:17:34PM +0800, Wanpeng Li wrote: > > From: Wanpeng Li > > > > The kick after setting KVM_REQ_PENDING_TIMER is used to handle the timer > > fires on a different pCPU which vCPU is running on, we don't need

Re: [PATCH] KVM: LAPIC: Don't kick vCPU which is injecting already-expired timer

2020-08-21 Thread Sean Christopherson
On Fri, Aug 21, 2020 at 05:17:34PM +0800, Wanpeng Li wrote: > From: Wanpeng Li > > The kick after setting KVM_REQ_PENDING_TIMER is used to handle the timer > fires on a different pCPU which vCPU is running on, we don't need this > kick when injecting already-expired timer, this kick is

[PATCH] KVM: LAPIC: Don't kick vCPU which is injecting already-expired timer

2020-08-21 Thread Wanpeng Li
From: Wanpeng Li The kick after setting KVM_REQ_PENDING_TIMER is used to handle the timer fires on a different pCPU which vCPU is running on, we don't need this kick when injecting already-expired timer, this kick is expensive since memory barrier, rcu, preemption disable/enable operations.