From patchwork Thu Jan 20 21:36:32 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rik van Riel X-Patchwork-Id: 492981 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 p0KLfXfI000893 for ; Thu, 20 Jan 2011 21:41:33 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755152Ab1ATVis (ORCPT ); Thu, 20 Jan 2011 16:38:48 -0500 Received: from mx1.redhat.com ([209.132.183.28]:26893 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754885Ab1ATVir (ORCPT ); Thu, 20 Jan 2011 16:38:47 -0500 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id p0KLcb0e028349 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 20 Jan 2011 16:38:37 -0500 Received: from annuminas.surriel.com (ovpn-113-70.phx2.redhat.com [10.3.113.70]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p0KLcWtD028639; Thu, 20 Jan 2011 16:38:35 -0500 Date: Thu, 20 Jan 2011 16:36:32 -0500 From: Rik van Riel To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Avi Kiviti , Srivatsa Vaddagiri , Peter Zijlstra , Mike Galbraith , Chris Wright , ttracy@redhat.com, dshaks@redhat.com, "Nakajima, Jun" Subject: [RFC -v6 PATCH 7/8] kvm: keep track of which task is running a KVM vcpu Message-ID: <20110120163632.021c3f37@annuminas.surriel.com> In-Reply-To: <20110120163127.2568f4fe@annuminas.surriel.com> References: <20110120163127.2568f4fe@annuminas.surriel.com> Organization: Red Hat, Inc. Mime-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.25 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]); Thu, 20 Jan 2011 21:41:33 +0000 (UTC) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index a055742..9d56ed5 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -81,6 +81,7 @@ struct kvm_vcpu { #endif int vcpu_id; struct mutex mutex; + struct pid *pid; int cpu; atomic_t guest_mode; struct kvm_run *run; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 5225052..86c4905 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -185,6 +185,7 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id) vcpu->cpu = -1; vcpu->kvm = kvm; vcpu->vcpu_id = id; + vcpu->pid = NULL; init_waitqueue_head(&vcpu->wq); page = alloc_page(GFP_KERNEL | __GFP_ZERO); @@ -208,6 +209,8 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_init); void kvm_vcpu_uninit(struct kvm_vcpu *vcpu) { + if (vcpu->pid) + put_pid(vcpu->pid); kvm_arch_vcpu_uninit(vcpu); free_page((unsigned long)vcpu->run); } @@ -1456,6 +1459,14 @@ static long kvm_vcpu_ioctl(struct file *filp, r = -EINVAL; if (arg) goto out; + if (unlikely(vcpu->pid != current->pids[PIDTYPE_PID].pid)) { + /* The thread running this VCPU changed. */ + struct pid *oldpid = vcpu->pid; + struct pid *newpid = get_task_pid(current, PIDTYPE_PID); + rcu_assign_pointer(vcpu->pid, newpid); + synchronize_rcu(); + put_pid(oldpid); + } r = kvm_arch_vcpu_ioctl_run(vcpu, vcpu->run); break; case KVM_GET_REGS: {