From patchwork Thu Mar 4 15:05:15 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 46914 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 002C4B7C98 for ; Fri, 5 Mar 2010 02:17:31 +1100 (EST) Received: from localhost ([127.0.0.1]:50726 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NnCno-00060M-Fn for incoming@patchwork.ozlabs.org; Thu, 04 Mar 2010 10:17:28 -0500 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NnCdJ-0002UH-Ak for qemu-devel@nongnu.org; Thu, 04 Mar 2010 10:06:37 -0500 Received: from [199.232.76.173] (port=44322 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NnCdI-0002Tk-8I for qemu-devel@nongnu.org; Thu, 04 Mar 2010 10:06:36 -0500 Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim 4.60) (envelope-from ) id 1NnCd9-0000f3-UD for qemu-devel@nongnu.org; Thu, 04 Mar 2010 10:06:35 -0500 Received: from mx1.redhat.com ([209.132.183.28]:35337) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NnCd8-0000eX-MM for qemu-devel@nongnu.org; Thu, 04 Mar 2010 10:06:27 -0500 Received: from int-mx05.intmail.prod.int.phx2.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.18]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o24F6OFp013476 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 4 Mar 2010 10:06:25 -0500 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx05.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o24F6O7T013874; Thu, 4 Mar 2010 10:06:24 -0500 Received: from amt.cnet (vpn-11-217.rdu.redhat.com [10.11.11.217]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id o24F6L62028974; Thu, 4 Mar 2010 10:06:22 -0500 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id 626E468A9F5; Thu, 4 Mar 2010 12:05:54 -0300 (BRT) Received: (from marcelo@localhost) by amt.cnet (8.14.3/8.14.3/Submit) id o24F5pPD028137; Thu, 4 Mar 2010 12:05:51 -0300 From: Marcelo Tosatti To: Anthony Liguori Date: Thu, 4 Mar 2010 12:05:15 -0300 Message-Id: In-Reply-To: References: X-Scanned-By: MIMEDefang 2.67 on 10.5.11.18 X-detected-operating-system: by monty-python.gnu.org: Genre and OS details not recognized. Cc: Jan Kiszka , Marcelo Tosatti , qemu-devel@nongnu.org, kvm@vger.kernel.org Subject: [Qemu-devel] [PATCH 5/6] KVM: x86: Restrict writeback of VCPU state X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Jan Kiszka Do not write nmi_pending, sipi_vector, and mpstate unless we at least go through a reset. And TSC as well as KVM wallclocks should only be written on full sync, otherwise we risk to drop some time on state read-modify-write. Signed-off-by: Jan Kiszka Signed-off-by: Marcelo Tosatti --- target-i386/kvm.c | 32 ++++++++++++++++++++------------ 1 files changed, 20 insertions(+), 12 deletions(-) diff --git a/target-i386/kvm.c b/target-i386/kvm.c index 2c834df..40f8303 100644 --- a/target-i386/kvm.c +++ b/target-i386/kvm.c @@ -546,7 +546,7 @@ static void kvm_msr_entry_set(struct kvm_msr_entry *entry, entry->data = value; } -static int kvm_put_msrs(CPUState *env) +static int kvm_put_msrs(CPUState *env, int level) { struct { struct kvm_msrs info; @@ -560,7 +560,6 @@ static int kvm_put_msrs(CPUState *env) kvm_msr_entry_set(&msrs[n++], MSR_IA32_SYSENTER_EIP, env->sysenter_eip); if (kvm_has_msr_star(env)) kvm_msr_entry_set(&msrs[n++], MSR_STAR, env->star); - kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc); #ifdef TARGET_X86_64 /* FIXME if lm capable */ kvm_msr_entry_set(&msrs[n++], MSR_CSTAR, env->cstar); @@ -568,8 +567,12 @@ static int kvm_put_msrs(CPUState *env) kvm_msr_entry_set(&msrs[n++], MSR_FMASK, env->fmask); kvm_msr_entry_set(&msrs[n++], MSR_LSTAR, env->lstar); #endif - kvm_msr_entry_set(&msrs[n++], MSR_KVM_SYSTEM_TIME, env->system_time_msr); - kvm_msr_entry_set(&msrs[n++], MSR_KVM_WALL_CLOCK, env->wall_clock_msr); + if (level == KVM_PUT_FULL_STATE) { + kvm_msr_entry_set(&msrs[n++], MSR_IA32_TSC, env->tsc); + kvm_msr_entry_set(&msrs[n++], MSR_KVM_SYSTEM_TIME, + env->system_time_msr); + kvm_msr_entry_set(&msrs[n++], MSR_KVM_WALL_CLOCK, env->wall_clock_msr); + } msr_data.info.nmsrs = n; @@ -782,7 +785,7 @@ static int kvm_get_mp_state(CPUState *env) return 0; } -static int kvm_put_vcpu_events(CPUState *env) +static int kvm_put_vcpu_events(CPUState *env, int level) { #ifdef KVM_CAP_VCPU_EVENTS struct kvm_vcpu_events events; @@ -806,8 +809,11 @@ static int kvm_put_vcpu_events(CPUState *env) events.sipi_vector = env->sipi_vector; - events.flags = - KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SIPI_VECTOR; + events.flags = 0; + if (level >= KVM_PUT_RESET_STATE) { + events.flags |= + KVM_VCPUEVENT_VALID_NMI_PENDING | KVM_VCPUEVENT_VALID_SIPI_VECTOR; + } return kvm_vcpu_ioctl(env, KVM_SET_VCPU_EVENTS, &events); #else @@ -899,15 +905,17 @@ int kvm_arch_put_registers(CPUState *env, int level) if (ret < 0) return ret; - ret = kvm_put_msrs(env); + ret = kvm_put_msrs(env, level); if (ret < 0) return ret; - ret = kvm_put_mp_state(env); - if (ret < 0) - return ret; + if (level >= KVM_PUT_RESET_STATE) { + ret = kvm_put_mp_state(env); + if (ret < 0) + return ret; + } - ret = kvm_put_vcpu_events(env); + ret = kvm_put_vcpu_events(env, level); if (ret < 0) return ret;