From patchwork Wed Jan 9 18:53:42 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eduardo Habkost X-Patchwork-Id: 210822 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 2380A2C0168 for ; Thu, 10 Jan 2013 06:09:12 +1100 (EST) Received: from localhost ([::1]:40409 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tt0m1-0003zV-0a for incoming@patchwork.ozlabs.org; Wed, 09 Jan 2013 13:53:13 -0500 Received: from eggs.gnu.org ([208.118.235.92]:50309) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tt0lL-0003Ak-DE for qemu-devel@nongnu.org; Wed, 09 Jan 2013 13:52:40 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Tt0lH-0005eJ-MC for qemu-devel@nongnu.org; Wed, 09 Jan 2013 13:52:31 -0500 Received: from mx1.redhat.com ([209.132.183.28]:63460) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tt0lH-0005dq-Be for qemu-devel@nongnu.org; Wed, 09 Jan 2013 13:52:27 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r09IqQ4g027762 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 9 Jan 2013 13:52:26 -0500 Received: from blackpad.lan.raisama.net (vpn1-7-24.gru2.redhat.com [10.97.7.24]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r09IqPTR011522; Wed, 9 Jan 2013 13:52:26 -0500 Received: by blackpad.lan.raisama.net (Postfix, from userid 500) id B2720203D1C; Wed, 9 Jan 2013 16:54:03 -0200 (BRST) From: Eduardo Habkost To: qemu-devel@nongnu.org Date: Wed, 9 Jan 2013 16:53:42 -0200 Message-Id: <1357757632-1950-3-git-send-email-ehabkost@redhat.com> In-Reply-To: <1357757632-1950-1-git-send-email-ehabkost@redhat.com> References: <1357757632-1950-1-git-send-email-ehabkost@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: kvm@vger.kernel.org, Gleb Natapov , "Michael S. Tsirkin" , Marcelo Tosatti , Igor Mammedov , =?UTF-8?q?Andreas=20F=C3=A4rber?= Subject: [Qemu-devel] [RFC 02/12] target-i386: Don't set any KVM flag by default if KVM is disabled X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org This is a cleanup that tries to solve two small issues: - We don't need a separate kvm_pv_eoi_features variable just to keep a constant calculated at compile-time, and this style would require adding a separate variable (that's declared twice because of the CONFIG_KVM ifdef) for each feature that's going to be enabled/disable by machine-type compat code. - The pc-1.3 code is setting the kvm_pv_eoi flag on cpuid_kvm_features even when KVM is disabled at runtime. This small incosistency in the cpuid_kvm_features field isn't a problem today because cpuid_kvm_features is ignored by the TCG code, but it may cause unexpected problems later when refactoring the CPUID handling code. This patch eliminates the kvm_pv_eoi_features variable and simply uses kvm_enabled() inside the enable_kvm_pv_eoi() compat function, so it enables kvm_pv_eoi only if KVM is enabled. I believe this makes the behavior of enable_kvm_pv_eoi() clearer and easier to understand. Signed-off-by: Eduardo Habkost Acked-by: Michael S. Tsirkin --- Cc: kvm@vger.kernel.org Cc: Michael S. Tsirkin Cc: Gleb Natapov Cc: Marcelo Tosatti Changes v2: - Coding style fix Changes v3: - Eliminate #ifdef by using the fake KVM_FEATURE_PV_EOI #define Changes v4: - Check kvm_enabled() when actually using kvm_default_features - Eliminate Yet Another #ifdef by using the fake KVM_FEATURE_* #defines on kvm_default_features initialization --- target-i386/cpu.c | 16 ++++++---------- 1 file changed, 6 insertions(+), 10 deletions(-) diff --git a/target-i386/cpu.c b/target-i386/cpu.c index e4dc370..57a22b7 100644 --- a/target-i386/cpu.c +++ b/target-i386/cpu.c @@ -206,22 +206,16 @@ typedef struct model_features_t { int check_cpuid = 0; int enforce_cpuid = 0; -#if defined(CONFIG_KVM) static uint32_t kvm_default_features = (1 << KVM_FEATURE_CLOCKSOURCE) | (1 << KVM_FEATURE_NOP_IO_DELAY) | (1 << KVM_FEATURE_CLOCKSOURCE2) | (1 << KVM_FEATURE_ASYNC_PF) | (1 << KVM_FEATURE_STEAL_TIME) | (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT); -static const uint32_t kvm_pv_eoi_features = (0x1 << KVM_FEATURE_PV_EOI); -#else -static uint32_t kvm_default_features = 0; -static const uint32_t kvm_pv_eoi_features = 0; -#endif void enable_kvm_pv_eoi(void) { - kvm_default_features |= kvm_pv_eoi_features; + kvm_default_features |= (1UL << KVM_FEATURE_PV_EOI); } void host_cpuid(uint32_t function, uint32_t count, @@ -1343,13 +1337,15 @@ static int cpu_x86_parse_featurestr(x86_def_t *x86_cpu_def, char *features) unsigned int i; char *featurestr; /* Single 'key=value" string being parsed */ /* Features to be added */ - FeatureWordArray plus_features = { - [FEAT_KVM] = kvm_default_features, - }; + FeatureWordArray plus_features = { 0 }; /* Features to be removed */ FeatureWordArray minus_features = { 0 }; uint32_t numvalue; + if (kvm_enabled()) { + plus_features[FEAT_KVM] = kvm_default_features; + } + add_flagname_to_bitmaps("hypervisor", plus_features); featurestr = features ? strtok(features, ",") : NULL;