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| author | Andrew Jones <drjones@redhat.com> | 2017-06-04 14:43:57 +0200 |
|---|---|---|
| committer | Christoffer Dall <cdall@linaro.org> | 2017-06-04 16:53:55 +0200 |
| commit | 424c989b1a664a270727550506321af0a605c302 (patch) | |
| tree | 752a20556538c34790cc5e4cdcdc96268dddad3f /virt | |
| parent | cc9b43f99d5ff4df75d11e75c0bfaf08f1ff5a9a (diff) | |
| download | linux-424c989b1a664a270727550506321af0a605c302.tar.gz | |
KVM: arm/arm64: optimize VCPU RUN
We can make a small optimization by not checking the state of the power_off field on each run. This is done by treating power_off like pause, only checking it when we get the EXIT VCPU request. When a VCPU powers off another VCPU the EXIT request is already made, so we just need to make sure the request is also made on self power off. kvm_vcpu_kick() isn't necessary for these cases, as the VCPU would just be kicking itself, but we add it anyway as a self kick doesn't cost much, and it makes the code more future-proof. Signed-off-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org>
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/arm/arm.c | 19 | ||||
| -rw-r--r-- | virt/kvm/arm/psci.c | 2 |
2 files changed, 13 insertions, 8 deletions
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c index 21a4db90073f..9379b1d75ad3 100644 --- a/virt/kvm/arm/arm.c +++ b/virt/kvm/arm/arm.c @@ -368,6 +368,13 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) kvm_timer_vcpu_put(vcpu); } +static void vcpu_power_off(struct kvm_vcpu *vcpu) +{ + vcpu->arch.power_off = true; + kvm_make_request(KVM_REQ_VCPU_EXIT, vcpu); + kvm_vcpu_kick(vcpu); +} + int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, struct kvm_mp_state *mp_state) { @@ -387,7 +394,7 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, vcpu->arch.power_off = false; break; case KVM_MP_STATE_STOPPED: - vcpu->arch.power_off = true; + vcpu_power_off(vcpu); break; default: return -EINVAL; @@ -557,7 +564,7 @@ static void vcpu_sleep(struct kvm_vcpu *vcpu) swait_event_interruptible(*wq, ((!vcpu->arch.power_off) && (!vcpu->arch.pause))); - if (vcpu->arch.pause) { + if (vcpu->arch.power_off || vcpu->arch.pause) { /* Awaken to handle a signal, request we sleep again later. */ kvm_make_request(KVM_REQ_VCPU_EXIT, vcpu); } @@ -623,9 +630,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) check_vcpu_requests(vcpu); - if (vcpu->arch.power_off) - vcpu_sleep(vcpu); - /* * Preparing the interrupts to be injected also * involves poking the GIC, which must be done in a @@ -662,8 +666,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) smp_store_mb(vcpu->mode, IN_GUEST_MODE); if (ret <= 0 || need_new_vmid_gen(vcpu->kvm) || - kvm_request_pending(vcpu) || - vcpu->arch.power_off) { + kvm_request_pending(vcpu)) { vcpu->mode = OUTSIDE_GUEST_MODE; local_irq_enable(); kvm_pmu_sync_hwstate(vcpu); @@ -896,7 +899,7 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, * Handle the "start in power-off" case. */ if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) - vcpu->arch.power_off = true; + vcpu_power_off(vcpu); else vcpu->arch.power_off = false; diff --git a/virt/kvm/arm/psci.c b/virt/kvm/arm/psci.c index f189d0ad30d5..4a436685c552 100644 --- a/virt/kvm/arm/psci.c +++ b/virt/kvm/arm/psci.c @@ -65,6 +65,8 @@ static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu) static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu) { vcpu->arch.power_off = true; + kvm_make_request(KVM_REQ_VCPU_EXIT, vcpu); + kvm_vcpu_kick(vcpu); } static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) |