summaryrefslogtreecommitdiff
path: root/arch/x86/kvm
diff options
context:
space:
mode:
authorAndrey Smetanin <asmetanin@virtuozzo.com>2015-12-28 18:27:24 +0300
committerPaolo Bonzini <pbonzini@redhat.com>2016-01-08 19:04:42 +0100
commitf3b138c5d89a1f74a2b46adaa1067aea9a7e3cbb (patch)
tree438ad25bcd5642ed1e2e55091824470a3ecac70b /arch/x86/kvm
parent7be58a6488a9d36886d9423a1ed54fe104c7b182 (diff)
kvm/x86: Update SynIC timers on guest entry only
Consolidate updating the Hyper-V SynIC timers in a single place: on guest entry in processing KVM_REQ_HV_STIMER request. This simplifies the overall logic, and makes sure the most current state of msrs and guest clock is used for arming the timers (to achieve that, KVM_REQ_HV_STIMER has to be processed after KVM_REQ_CLOCK_UPDATE). Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
-rw-r--r--arch/x86/kvm/hyperv.c38
-rw-r--r--arch/x86/kvm/x86.c6
2 files changed, 25 insertions, 19 deletions
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index ddae13eed075..101c2e4a0255 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -389,7 +389,7 @@ static u64 get_time_ref_counter(struct kvm *kvm)
return div_u64(get_kernel_ns() + kvm->arch.kvmclock_offset, 100);
}
-static void stimer_mark_expired(struct kvm_vcpu_hv_stimer *stimer,
+static void stimer_mark_pending(struct kvm_vcpu_hv_stimer *stimer,
bool vcpu_kick)
{
struct kvm_vcpu *vcpu = stimer_to_vcpu(stimer);
@@ -417,7 +417,7 @@ static enum hrtimer_restart stimer_timer_callback(struct hrtimer *timer)
struct kvm_vcpu_hv_stimer *stimer;
stimer = container_of(timer, struct kvm_vcpu_hv_stimer, timer);
- stimer_mark_expired(stimer, true);
+ stimer_mark_pending(stimer, true);
return HRTIMER_NORESTART;
}
@@ -462,7 +462,7 @@ static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
* "If a one shot is enabled and the specified count is in
* the past, it will expire immediately."
*/
- stimer_mark_expired(stimer, false);
+ stimer_mark_pending(stimer, false);
return 0;
}
@@ -475,30 +475,24 @@ static int stimer_start(struct kvm_vcpu_hv_stimer *stimer)
static int stimer_set_config(struct kvm_vcpu_hv_stimer *stimer, u64 config,
bool host)
{
+ stimer_cleanup(stimer);
if ((stimer->config & HV_STIMER_ENABLE) && HV_STIMER_SINT(config) == 0)
config &= ~HV_STIMER_ENABLE;
stimer->config = config;
- stimer_cleanup(stimer);
- if (stimer->config & HV_STIMER_ENABLE)
- if (stimer_start(stimer))
- return 1;
+ stimer_mark_pending(stimer, false);
return 0;
}
static int stimer_set_count(struct kvm_vcpu_hv_stimer *stimer, u64 count,
bool host)
{
- stimer->count = count;
-
stimer_cleanup(stimer);
+ stimer->count = count;
if (stimer->count == 0)
stimer->config &= ~HV_STIMER_ENABLE;
- else if (stimer->config & HV_STIMER_AUTOENABLE) {
+ else if (stimer->config & HV_STIMER_AUTOENABLE)
stimer->config |= HV_STIMER_ENABLE;
- if (stimer_start(stimer))
- return 1;
- }
-
+ stimer_mark_pending(stimer, false);
return 0;
}
@@ -582,18 +576,24 @@ void kvm_hv_process_stimers(struct kvm_vcpu *vcpu)
{
struct kvm_vcpu_hv *hv_vcpu = vcpu_to_hv_vcpu(vcpu);
struct kvm_vcpu_hv_stimer *stimer;
- u64 time_now;
+ u64 time_now, exp_time;
int i;
for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++)
if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) {
stimer = &hv_vcpu->stimer[i];
if (stimer->config & HV_STIMER_ENABLE) {
- time_now = get_time_ref_counter(vcpu->kvm);
- if (time_now >= stimer->exp_time)
- stimer_expiration(stimer);
+ exp_time = stimer->exp_time;
+
+ if (exp_time) {
+ time_now =
+ get_time_ref_counter(vcpu->kvm);
+ if (time_now >= exp_time)
+ stimer_expiration(stimer);
+ }
- if (stimer->config & HV_STIMER_ENABLE)
+ if ((stimer->config & HV_STIMER_ENABLE) &&
+ stimer->count)
stimer_start(stimer);
else
stimer_cleanup(stimer);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 107ceaf8cbd0..fad1d096919e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6508,6 +6508,12 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
r = 0;
goto out;
}
+
+ /*
+ * KVM_REQ_HV_STIMER has to be processed after
+ * KVM_REQ_CLOCK_UPDATE, because Hyper-V SynIC timers
+ * depend on the guest clock being up-to-date
+ */
if (kvm_check_request(KVM_REQ_HV_STIMER, vcpu))
kvm_hv_process_stimers(vcpu);
}