2016-03-18 02:44+0700, Suravee Suthikulpanit: > On 3/10/16 03:55, Radim Krčmář wrote: >>2016-03-04 14:46-0600, Suravee Suthikulpanit: >>>>From: Suravee Suthikulpanit<[email protected]> >>>> >>>>Introduce VMEXIT handlers, avic_incp_ipi_interception() and >>>>avic_noaccel_interception(). >>>> >>>>Signed-off-by: Suravee Suthikulpanit<[email protected]> >>>>--- >>>>diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c >>>>@@ -3690,6 +3690,264 @@ static int mwait_interception(struct vcpu_svm *svm) >>>>+ case AVIC_INCMP_IPI_ERR_TARGET_NOT_RUN: { >>>>+ kvm_for_each_vcpu(i, vcpu, kvm) { >>>>+ if (!kvm_apic_match_dest(vcpu, apic, >>>>+ icrl & APIC_SHORT_MASK, >>>>+ GET_APIC_DEST_FIELD(icrh), >>>>+ icrl & APIC_DEST_MASK)) >>>>+ continue; >>>>+ >>>>+ kvm_vcpu_kick(vcpu); >>KVM shouldn't kick VCPUs that are running. (Imagine a broadcast when >>most VCPUs are in guest mode.) > > So, besides checking if the vcpu match the destination, I will add the check > to see if the is_running bit is set before calling kvm_vcpu_kick()
That will do. >>I think a new helper might be useful here: we only want to wake up from >>wait queue, but never force VCPU out of guest mode ... kvm_vcpu_kick() >>does both. > > If I only kick non-running vcpu, do I still need this new helper function? I would prefer it. It's a minor performance optimization (non-running VCPUs aren't in guest mode) and makes our intent clear. Please use include the following patch and use kvm_vcpu_wake_up instead. ---8<--- AVIC has a use for kvm_vcpu_wake_up. Signed-off-by: Radim Krčmář <[email protected]> --- include/linux/kvm_host.h | 1 + virt/kvm/kvm_main.c | 19 +++++++++++++------ 2 files changed, 14 insertions(+), 6 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 861f690aa791..7b269626a3b3 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -650,6 +650,7 @@ void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn); void kvm_vcpu_block(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu); void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu); +void kvm_vcpu_wake_up(struct kvm_vcpu *vcpu); void kvm_vcpu_kick(struct kvm_vcpu *vcpu); int kvm_vcpu_yield_to(struct kvm_vcpu *target); void kvm_vcpu_on_spin(struct kvm_vcpu *vcpu); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 1eae05236347..c39c54afdb74 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2054,13 +2054,8 @@ out: EXPORT_SYMBOL_GPL(kvm_vcpu_block); #ifndef CONFIG_S390 -/* - * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode. - */ -void kvm_vcpu_kick(struct kvm_vcpu *vcpu) +void kvm_vcpu_wake_up(struct kvm_vcpu *vcpu) { - int me; - int cpu = vcpu->cpu; wait_queue_head_t *wqp; wqp = kvm_arch_vcpu_wq(vcpu); @@ -2068,6 +2063,18 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu) wake_up_interruptible(wqp); ++vcpu->stat.halt_wakeup; } +} +EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up); + +/* + * Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode. + */ +void kvm_vcpu_kick(struct kvm_vcpu *vcpu) +{ + int me; + int cpu = vcpu->cpu; + + kvm_vcpu_wake_up(vcpu); me = get_cpu(); if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu)) -- 2.7.2
