From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74BD2C43142 for ; Tue, 31 Jul 2018 09:08:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 21E14208A5 for ; Tue, 31 Jul 2018 09:08:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="dSjBxnQ+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 21E14208A5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731650AbeGaKsE (ORCPT ); Tue, 31 Jul 2018 06:48:04 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:37935 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729731AbeGaKsE (ORCPT ); Tue, 31 Jul 2018 06:48:04 -0400 Received: by mail-pf1-f195.google.com with SMTP id x17-v6so5826994pfh.5; Tue, 31 Jul 2018 02:08:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=qPZy/b6eKage80HTzUF1LOnlyLHY9Ot7/cUJYnTCj+c=; b=dSjBxnQ+SGhWpbDY44kc3e7LFvqx1Z3pJ6LXgsK0G8tLgAN1jsC+dP1p3nZAr1xjAM +VUzyJ0dnFwEfSdD5hIx8j6swpIFAzS1XyIfyT9fU/VDW9yDuhQNBPHlMvZHjNxi0teX qXOX9IwwfHoBdgkVFEW3R8tserfC8uw0fjlV2n7Kh+RZirp6//PU3xIGortTrgk2/CXO r6N7ClnIC11OYHaU5AW4uTH2Gblemu+E8Na8QDAMwWRO9ox9wUFc5a1mt/QJwM07Y5Jg 0QgkKo2TMM2lismYN83HQmqnf+JJ2+gBrPOPDX/88O1VFRJ9BrpJExkeMdsx5NlnUroI LRlA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=qPZy/b6eKage80HTzUF1LOnlyLHY9Ot7/cUJYnTCj+c=; b=q4qn7i7F5J9lVHlVQY5p7O5IBMUzNapC/AOlRN1cedo7pWV1zOpDtY3eUGuSovr6WP soQvv5M8XmKp1ffBcDWcZWHRaPIU3OsB+Eq1sUXNDJW8AKZdxc2+8RldDQkSUHZFim5+ tCUFw9fA7uJ0lQbn92Z3mERwiIGh+mGM1H4g4PpKZlXj1kUbXsX4iEHoSoMvb/jMX5vV YcmbD9Ik5u9PP3EQytnuu2N3vnc59FxDd1dTSE4mP/CH/KEz0F2Vl2n5v9AatA7OdXd1 I3hUJWQumkJPFOqSdkiWviRGQRNTwxcvNrVJ5Hda7Gz9ODaT5gZ5UBs4vA5XUrP3qzma hO9g== X-Gm-Message-State: AOUpUlFzTqSbLbB9ubAc0WyNbIrZ/uDguvI9ocg0UlP3DLXak+GLIAT2 frlO2WcMD9CRAZ6VqZ2142w= X-Google-Smtp-Source: AAOMgpcocVqK13KpiFbKWcoLWYMLWNT2kAnXyMLTLi36TmShNMCkOfobVPwRpzXLEE/dUiq7c8rNzA== X-Received: by 2002:a63:c80e:: with SMTP id z14-v6mr19242432pgg.77.1533028122920; Tue, 31 Jul 2018 02:08:42 -0700 (PDT) Received: from VM_0_3_centos.localdomain ([193.112.143.122]) by smtp.gmail.com with ESMTPSA id c142-v6sm18059301pfb.62.2018.07.31.02.08.40 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 31 Jul 2018 02:08:42 -0700 (PDT) From: Chen Xiao To: pbonzini@redhat.com, rkrcmar@redhat.com Cc: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Chen Xiao , Chen Xiao Subject: [PATCH] KVM: X86: Disable KVM_FEATURE_STEAL_TIME when both delayacct_on added to cmdline and CONFIG_SCHEDSTATS is set Date: Tue, 31 Jul 2018 17:08:15 +0800 Message-Id: <1533028095-4773-1-git-send-email-abigwc@gmail.com> X-Mailer: git-send-email 1.8.3.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chen Xiao When sched_info_on returns 1，KVM_FEATURE_STEAL_TIME will be set, steal% can be seen in the virtual machine.The returned value of sched_info_on depends on delayacct_on. If nodelayacct is added to kernel boot cmdline,the KVM_FEATURE_STEAL_TIME will be turned off by setting delayacct_on to 0.When CONFIG_SCHEDSTATS is set, sched_info_on always returns 1, and adding nodelayacct to the cmdline cannot turn off the KVM_FEATURE_STEAL_TIME Sometimes the users do not want the running state of host to be perceived in the virtual machine, and intend to turn off KVM_FEATURE_STEAL_TIME. The requirement is not available, however, when CONFIG_SCHEDSTATS has been set.Modify the judgment criteria for being set up from KVM_FEATURE_STEAL_TIME, and it is only be judged by the value of delayacct_on. Signed-off-by: Chen Xiao --- arch/x86/kvm/cpuid.c | 2 +- arch/x86/kvm/x86.c | 8 ++++---- arch/x86/kvm/x86.h | 10 ++++++++++ 3 files changed, 15 insertions(+), 5 deletions(-) diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 7e042e3..d38da09 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -623,7 +623,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, (1 << KVM_FEATURE_PV_TLB_FLUSH) | (1 << KVM_FEATURE_ASYNC_PF_VMEXIT); - if (sched_info_on()) + if (kvm_feature_steal_on()) entry->eax |= (1 << KVM_FEATURE_STEAL_TIME); entry->ebx = 0; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2b812b3..8371d5c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2424,8 +2424,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) return 1; break; case MSR_KVM_STEAL_TIME: - - if (unlikely(!sched_info_on())) + if (unlikely(!kvm_feature_steal_on())) return 1; if (data & KVM_STEAL_RESERVED_MASK) @@ -3101,7 +3100,8 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) vcpu->cpu = cpu; } - kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); + if (kvm_feature_steal_on()) + kvm_make_request(KVM_REQ_STEAL_UPDATE, vcpu); } static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu) @@ -7291,7 +7291,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) r = 1; goto out; } - if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) + if (kvm_feature_steal_on() + && kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu)) record_steal_time(vcpu); if (kvm_check_request(KVM_REQ_SMI, vcpu)) process_smi(vcpu); diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 257f276..9e7c078 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -338,4 +338,14 @@ static inline void kvm_after_interrupt(struct kvm_vcpu *vcpu) __this_cpu_write(current_vcpu, NULL); } +static inline int kvm_feature_steal_on(void) +{ +#ifdef CONFIG_TASK_DELAY_ACCT + extern int delayacct_on; + return delayacct_on; +#else + return 0; +#endif +} + #endif -- 1.8.3.1