From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zachary Amsden Subject: [PATCH: kvm 5/6] Don't unconditionally clear cpu_khz_tsc in hardware_enable. Date: Wed, 23 Sep 2009 17:29:04 -1000 Message-ID: <1253762945-5750-5-git-send-email-zamsden@redhat.com> References: <1253762945-5750-1-git-send-email-zamsden@redhat.com> <1253762945-5750-2-git-send-email-zamsden@redhat.com> <1253762945-5750-3-git-send-email-zamsden@redhat.com> <1253762945-5750-4-git-send-email-zamsden@redhat.com> Cc: linux-kernel@vger.kernel.org, Zachary Amsden , Avi Kivity , Marcelo Tosatti To: kvm@vger.kernel.org Return-path: In-Reply-To: <1253762945-5750-4-git-send-email-zamsden@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org For the non-hotplug case, this TSC speed should be available; instead, clear cpu_khz_tsc when bringing down a CPU so it is recomputed at the next bringup. Signed-off-by: Zachary Amsden --- arch/x86/kvm/x86.c | 12 +++++------- 1 files changed, 5 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 38ba4a6..f1470ce 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4721,18 +4721,16 @@ int kvm_arch_cpu_hotadd(int cpu) void kvm_arch_cpu_hotremove(int cpu) { + /* + * Reset TSC khz to zero so it is recomputed on bringup + */ + if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) + per_cpu(cpu_tsc_khz, cpu) = 0; kvm_x86_ops->cpu_hotremove(cpu); } int kvm_arch_hardware_enable(void *garbage) { - /* - * Notifier callback chain may not have called cpufreq code - * yet, thus we must reset TSC khz to zero and recompute it - * before entering. - */ - if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) - per_cpu(cpu_tsc_khz, raw_smp_processor_id()) = 0; return kvm_x86_ops->hardware_enable(garbage); } -- 1.6.4.4