From patchwork Fri Jan 7 07:47:51 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Guangrong X-Patchwork-Id: 462851 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id p077mI8r004435 for ; Fri, 7 Jan 2011 07:48:18 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751990Ab1AGHrz (ORCPT ); Fri, 7 Jan 2011 02:47:55 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:58563 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751834Ab1AGHry (ORCPT ); Fri, 7 Jan 2011 02:47:54 -0500 Received: from tang.cn.fujitsu.com (tang.cn.fujitsu.com [10.167.250.3]) by song.cn.fujitsu.com (Postfix) with ESMTP id 3EFA0170237; Fri, 7 Jan 2011 15:47:52 +0800 (CST) Received: from mailserver.fnst.cn.fujitus.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id p077gjQk017871; Fri, 7 Jan 2011 15:42:45 +0800 Received: from eric.localdomain ([10.167.225.99]) by mailserver.fnst.cn.fujitus.com (Lotus Domino Release 8.5.1FP4) with ESMTP id 2011010715473095-118771 ; Fri, 7 Jan 2011 15:47:30 +0800 Message-ID: <4D26C527.9090403@cn.fujitsu.com> Date: Fri, 07 Jan 2011 15:47:51 +0800 From: Xiao Guangrong User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Thunderbird/3.1.7 MIME-Version: 1.0 To: Avi Kivity CC: Marcelo Tosatti , LKML , KVM Subject: [PATCH v2 2/3] KVM: send IPI to vcpu only when it's in guest mode References: <4D26C4D4.30303@cn.fujitsu.com> In-Reply-To: <4D26C4D4.30303@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2011-01-07 15:47:30, Serialize by Router on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2011-01-07 15:47:31, Serialize complete at 2011-01-07 15:47:31 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter1.kernel.org [140.211.167.41]); Fri, 07 Jan 2011 07:48:18 +0000 (UTC) diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c index 70d224d..15c11b2 100644 --- a/arch/ia64/kvm/kvm-ia64.c +++ b/arch/ia64/kvm/kvm-ia64.c @@ -662,6 +662,7 @@ again: goto vcpu_run_fail; srcu_read_unlock(&vcpu->kvm->srcu, idx); + atomic_set(&vcpu->guest_mode, 1); kvm_guest_enter(); /* @@ -683,6 +684,7 @@ again: */ barrier(); kvm_guest_exit(); + atomic_set(&vcpu->guest_mode, 0); preempt_enable(); idx = srcu_read_lock(&vcpu->kvm->srcu); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0b77e9c..f882158 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -5214,7 +5214,11 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) kvm_load_guest_xcr0(vcpu); atomic_set(&vcpu->guest_mode, 1); - smp_wmb(); + + /* We should set ->guest_mode before check ->requests, + * see the comment in make_all_cpus_request. + */ + smp_mb(); local_irq_disable(); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index b5021db..5f5ef74 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -103,14 +103,15 @@ struct kvm_vcpu { #ifdef CONFIG_PREEMPT_NOTIFIERS struct preempt_notifier preempt_notifier; #endif + int cpu; int vcpu_id; - struct mutex mutex; - int cpu; + int srcu_idx; atomic_t guest_mode; - struct kvm_run *run; unsigned long requests; unsigned long guest_debug; - int srcu_idx; + + struct mutex mutex; + struct kvm_run *run; int fpu_active; int guest_fpu_loaded, guest_xcr0_loaded; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index b1b6cbb..a475264 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -153,7 +153,12 @@ static bool make_all_cpus_request(struct kvm *kvm, unsigned int req) if (kvm_make_check_request(req, vcpu)) continue; cpu = vcpu->cpu; - if (cpus != NULL && cpu != -1 && cpu != me) + + /* Set ->requests bit before we read ->guest_mode */ + smp_mb(); + + if (cpus != NULL && cpu != -1 && cpu != me && + atomic_read(&vcpu->guest_mode)) cpumask_set_cpu(cpu, cpus); } if (unlikely(cpus == NULL))