From mboxrd@z Thu Jan 1 00:00:00 1970 From: Igor Mammedov Subject: Re: [RFC 02/12] target-i386: Don't set any KVM flag by default if KVM is disabled Date: Fri, 11 Jan 2013 00:07:40 +0100 Message-ID: <20130111000740.774084f3@thinkpad.mammed.net> References: <1357757632-1950-1-git-send-email-ehabkost@redhat.com> <1357757632-1950-3-git-send-email-ehabkost@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, Gleb Natapov , "Michael S. Tsirkin" , Marcelo Tosatti , qemu-devel@nongnu.org, Andreas =?UTF-8?B?RsOkcmJlcg==?= To: Eduardo Habkost Return-path: In-Reply-To: <1357757632-1950-3-git-send-email-ehabkost@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org Sender: qemu-devel-bounces+gceq-qemu-devel=gmane.org@nongnu.org List-Id: kvm.vger.kernel.org On Wed, 9 Jan 2013 16:53:42 -0200 Eduardo Habkost wrote: > 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 > --- > Cc: kvm@vger.kernel.org > Cc: Michael S. Tsirkin > Cc: Gleb Natapov > Cc: Marcelo Tosatti > [snip] > 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; > + } While touching it please move setting defaults to cpu_x86_register() or cpu_x86_find_by_name() to so that cpu_x86_parse_featurestr() would deal only with custom settings. [snip] -- Regards, Igor