From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932180AbdK1EHG (ORCPT ); Mon, 27 Nov 2017 23:07:06 -0500 Received: from mail-pg0-f67.google.com ([74.125.83.67]:43327 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753480AbdK1EGF (ORCPT ); Mon, 27 Nov 2017 23:06:05 -0500 X-Google-Smtp-Source: AGs4zMbjMTZmTb1jcVCmsaae3HuOf55TAvNmM9P6SMaiRmCMyg7S2iEGuK8ZUYj65/1GWNXaZJHInQ== From: Wanpeng Li X-Google-Original-From: Wanpeng Li To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Wanpeng Li , Peter Zijlstra Subject: [PATCH v6 1/4] KVM: X86: Add vCPU running/preempted state Date: Mon, 27 Nov 2017 20:05:52 -0800 Message-Id: <1511841955-7375-2-git-send-email-wanpeng.li@hotmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1511841955-7375-1-git-send-email-wanpeng.li@hotmail.com> References: <1511841955-7375-1-git-send-email-wanpeng.li@hotmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wanpeng Li This patch reuses the preempted field in kvm_steal_time, and will export the vcpu running/pre-empted information to the guest from host. This will enable guest to intelligently send ipi to running vcpus and set flag for pre-empted vcpus. This will prevent waiting for vcpus that are not running. Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Peter Zijlstra Signed-off-by: Wanpeng Li --- arch/x86/include/uapi/asm/kvm_para.h | 3 +++ arch/x86/kernel/kvm.c | 2 +- arch/x86/kvm/x86.c | 4 ++-- 3 files changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/x86/include/uapi/asm/kvm_para.h b/arch/x86/include/uapi/asm/kvm_para.h index 09cc064..763b692 100644 --- a/arch/x86/include/uapi/asm/kvm_para.h +++ b/arch/x86/include/uapi/asm/kvm_para.h @@ -51,6 +51,9 @@ struct kvm_steal_time { __u32 pad[11]; }; +#define KVM_VCPU_NOT_PREEMPTED (0 << 0) +#define KVM_VCPU_PREEMPTED (1 << 0) + #define KVM_CLOCK_PAIRING_WALLCLOCK 0 struct kvm_clock_pairing { __s64 sec; diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index b40ffbf..6610b92 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -643,7 +643,7 @@ __visible bool __kvm_vcpu_is_preempted(long cpu) { struct kvm_steal_time *src = &per_cpu(steal_time, cpu); - return !!src->preempted; + return !!(src->preempted & KVM_VCPU_PREEMPTED); } PV_CALLEE_SAVE_REGS_THUNK(__kvm_vcpu_is_preempted); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 990df39..bc501aa 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2130,7 +2130,7 @@ static void record_steal_time(struct kvm_vcpu *vcpu) &vcpu->arch.st.steal, sizeof(struct kvm_steal_time)))) return; - vcpu->arch.st.steal.preempted = 0; + vcpu->arch.st.steal.preempted = KVM_VCPU_NOT_PREEMPTED; if (vcpu->arch.st.steal.version & 1) vcpu->arch.st.steal.version += 1; /* first time write, random junk */ @@ -2907,7 +2907,7 @@ static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu) if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED)) return; - vcpu->arch.st.steal.preempted = 1; + vcpu->arch.st.steal.preempted = KVM_VCPU_PREEMPTED; kvm_write_guest_offset_cached(vcpu->kvm, &vcpu->arch.st.stime, &vcpu->arch.st.steal.preempted, -- 2.7.4