From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44327) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aBhbr-00089F-2r for qemu-devel@nongnu.org; Wed, 23 Dec 2015 06:29:36 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aBhbp-0002HT-Ps for qemu-devel@nongnu.org; Wed, 23 Dec 2015 06:29:34 -0500 Received: from mailhub.sw.ru ([195.214.232.25]:38439 helo=relay.sw.ru) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aBhbp-0002Gn-5w for qemu-devel@nongnu.org; Wed, 23 Dec 2015 06:29:33 -0500 From: Andrey Smetanin Date: Wed, 23 Dec 2015 14:28:41 +0300 Message-Id: <1450870121-15943-7-git-send-email-asmetanin@virtuozzo.com> In-Reply-To: <1450870121-15943-1-git-send-email-asmetanin@virtuozzo.com> References: <1450870121-15943-1-git-send-email-asmetanin@virtuozzo.com> Subject: [Qemu-devel] [PATCH v1 6/6] kvm/x86: Update SynIC timers on guest entry only List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: kvm@vger.kernel.org Cc: Gleb Natapov , Paolo Bonzini , qemu-devel@nongnu.org, Roman Kagan , "Denis V. Lunev" 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 Reviewed-by: Roman Kagan CC: Gleb Natapov CC: Paolo Bonzini CC: Roman Kagan CC: Denis V. Lunev CC: qemu-devel@nongnu.org --- arch/x86/kvm/hyperv.c | 35 +++++++++++++++++------------------ arch/x86/kvm/x86.c | 6 ++++++ 2 files changed, 23 insertions(+), 18 deletions(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index d7e6651..7857329 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; } @@ -460,7 +460,7 @@ 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; } @@ -473,30 +473,24 @@ 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; } @@ -580,16 +574,21 @@ 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) stimer_start(stimer); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b6102c1..795c14c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6492,6 +6492,12 @@ 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); } -- 2.4.3