From mboxrd@z Thu Jan 1 00:00:00 1970 From: Glauber Costa Subject: [RFC v2 3/7] measure time out of guest Date: Mon, 30 Aug 2010 12:06:22 -0400 Message-ID: <1283184391-7785-7-git-send-email-glommer@redhat.com> References: <1283184391-7785-1-git-send-email-glommer@redhat.com> <1283184391-7785-2-git-send-email-glommer@redhat.com> <1283184391-7785-3-git-send-email-glommer@redhat.com> <1283184391-7785-4-git-send-email-glommer@redhat.com> <1283184391-7785-5-git-send-email-glommer@redhat.com> <1283184391-7785-6-git-send-email-glommer@redhat.com> Cc: avi@redhat.com, zamsden@redhat.com, mtosatti@redhat.com, riel@redhat.com, peterz@infradead.org, mingo@elte.hu, jeremy@goop.org To: kvm@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:13000 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753974Ab0H3QXq (ORCPT ); Mon, 30 Aug 2010 12:23:46 -0400 In-Reply-To: <1283184391-7785-6-git-send-email-glommer@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: By measuring time between a vcpu_put and a vcpu_load, we can estimate how much time did the guest stay out of the cpu. This is exported to the guest at every clock update. Signed-off-by: Glauber Costa --- arch/x86/include/asm/kvm_host.h | 2 ++ arch/x86/kvm/x86.c | 13 +++++++++++-- 2 files changed, 13 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 502e53f..bc28aff 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -364,6 +364,8 @@ struct kvm_vcpu_arch { u64 hv_vapic; cpumask_var_t wbinvd_dirty_mask; + u64 time_out; + u64 last_time_out; }; struct kvm_arch { diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index f4b77ea..9d08032 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -906,6 +906,7 @@ static void kvm_write_guest_time(struct kvm_vcpu *v, bool update_time) if ((!vcpu->time_page)) return; + vcpu->hv_clock.steal_time = vcpu->time_out / 1000000; if (!update_time) return; @@ -928,8 +929,7 @@ static void kvm_write_guest_time(struct kvm_vcpu *v, bool update_time) vcpu->hv_clock.system_time = ts.tv_nsec + (NSEC_PER_SEC * (u64)ts.tv_sec) + v->kvm->arch.kvmclock_offset; - vcpu->hv_clock.flags = 0; - + vcpu->hv_clock.flags = PVCLOCK_STEAL_BIT; /* * The interface expects us to write an even number signaling that the * update is finished. Since the guest won't see the intermediate @@ -1801,6 +1801,8 @@ static bool need_emulate_wbinvd(struct kvm_vcpu *vcpu) void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { + s64 now; + /* Address WBINVD may be executed by guest */ if (need_emulate_wbinvd(vcpu)) { if (kvm_x86_ops->has_wbinvd_exit()) @@ -1818,12 +1820,19 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) per_cpu(cpu_tsc_khz, cpu) = khz; } kvm_request_guest_time_update(vcpu); + + now = getnsboottime(); + + if (vcpu->arch.last_time_out != 0) + vcpu->arch.time_out += now - vcpu->arch.last_time_out; } void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) { kvm_x86_ops->vcpu_put(vcpu); kvm_put_guest_fpu(vcpu); + + vcpu->arch.last_time_out = getnsboottime(); } static int is_efer_nx(void) -- 1.6.2.2