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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 6A989C55186 for ; Fri, 24 Apr 2020 06:23:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 459F320700 for ; Fri, 24 Apr 2020 06:23:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="mSBtBjdu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726683AbgDXGXH (ORCPT ); Fri, 24 Apr 2020 02:23:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51290 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726665AbgDXGXG (ORCPT ); Fri, 24 Apr 2020 02:23:06 -0400 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EAFAFC09B047; Thu, 23 Apr 2020 23:23:05 -0700 (PDT) Received: by mail-pf1-x441.google.com with SMTP id 18so3104325pfv.8; Thu, 23 Apr 2020 23:23:05 -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:in-reply-to:references; bh=zsPf//Pz+Ikh6+DsYPyUBP5glvQEMcSomDR2Wz5ze9I=; b=mSBtBjduNX75Q8OPv0HvHykSL62EEwkpC7HS/ITEACsut+AYwVLLBPMn0lKKb6YjVk b0w4uYU1Mi3+aX76+Yldo98XKTAYA/8//z/hk53fOkn6I1fYaLEK3/FKsG25ZzPAwQjB o1aqF3s56c+2xx7kpSXXtpHbJ7bF7uZ39ff7ABCleS+Gycqz5D1INBJxz+yUwRHva7Dg PkN2XR2r8a2SLfAQVIfKdE+6VKwYo9lnGoSwSA19O8nbT6s2TIXM6z1tXnUg/5ERfsX1 Yt973ARfSZDV89nTe8wPdROMoBBTVTIB039HvOmYHpOOpOTkhmC/dflxB6fMeMByKgWY Q84w== 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:in-reply-to :references; bh=zsPf//Pz+Ikh6+DsYPyUBP5glvQEMcSomDR2Wz5ze9I=; b=bvgNIdGE0Whfgto5Uh9paCCO6/udGxHjvsCp/HOG46LffyVy7Yq3etSaUeGu1pl3kw lgP/DYB7qWDVzwOuqd2rk/a7LGz9cHoA/QNslZZYt+sbjK3Ep8PwM3aFM9qEerqG9m13 58sJyI4TjRD4ZRGWOthWWHNodrP+/HP76g9wtOopAbiPWyguM8wbtnSbu20SchkGEPYc OH/b2jLHXgRS7tTc3jrfJD+a/4jCcZrW9sKvSTSJaoKhLI2pIU+YFJHWbmwJTBp0uBpx fAVMaG2EUxTMbzs/Tfl/6e9LbLsFyicrT+fcN/HBFbMG7EuTm0jdxlZcOUmBmLAp7h9k g7sQ== X-Gm-Message-State: AGi0PuZru2ASqSw8Ze+BrlSnuCbFsyRpy9nY0EBZ1YeEDGE/JTfFgUYg MOpmVvmynoM0Ejc2aLz51UigKYY4 X-Google-Smtp-Source: APiQypJ1ixZkeAqhQDfMzttF2Fw3E7k+vFcjhPVtqlT3SLiCtjcXny5qyc20qxRsSEd27zZLt9KPlQ== X-Received: by 2002:a62:34c1:: with SMTP id b184mr7844399pfa.73.1587709385259; Thu, 23 Apr 2020 23:23:05 -0700 (PDT) Received: from localhost.localdomain ([103.7.29.6]) by smtp.googlemail.com with ESMTPSA id l30sm3920674pgu.29.2020.04.23.23.23.02 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 23 Apr 2020 23:23:04 -0700 (PDT) From: Wanpeng Li X-Google-Original-From: Wanpeng Li To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Haiwei Li Subject: [PATCH v3 3/5] KVM: VMX: Optimize posted-interrupt delivery for timer fastpath Date: Fri, 24 Apr 2020 14:22:42 +0800 Message-Id: <1587709364-19090-4-git-send-email-wanpengli@tencent.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1587709364-19090-1-git-send-email-wanpengli@tencent.com> References: <1587709364-19090-1-git-send-email-wanpengli@tencent.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wanpeng Li Optimizing posted-interrupt delivery especially for the timer fastpath scenario, I observe kvm_x86_ops.deliver_posted_interrupt() has more latency then vmx_sync_pir_to_irr() in the case of timer fastpath scenario, since it needs to wait vmentry, after that it can handle external interrupt, ack the notification vector, read posted-interrupt descriptor etc, it is slower than evaluate and delivery during vmentry immediately approach. Let's skip sending interrupt to notify target pCPU and replace by vmx_sync_pir_to_irr() before each cont_run. Tested-by: Haiwei Li Cc: Haiwei Li Signed-off-by: Wanpeng Li --- arch/x86/kvm/vmx/vmx.c | 9 ++++++--- virt/kvm/kvm_main.c | 1 + 2 files changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 5c21027..d21b66b 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -3909,8 +3909,9 @@ static int vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector) if (pi_test_and_set_on(&vmx->pi_desc)) return 0; - if (!kvm_vcpu_trigger_posted_interrupt(vcpu, false)) - kvm_vcpu_kick(vcpu); + if (vcpu != kvm_get_running_vcpu() && + !kvm_vcpu_trigger_posted_interrupt(vcpu, false)) + kvm_vcpu_kick(vcpu); return 0; } @@ -6757,8 +6758,10 @@ static enum exit_fastpath_completion vmx_vcpu_run(struct kvm_vcpu *vcpu) if (!kvm_need_cancel_enter_guest(vcpu)) { exit_fastpath = vmx_exit_handlers_fastpath(vcpu); /* static call is better with retpolines */ - if (exit_fastpath == EXIT_FASTPATH_CONT_RUN) + if (exit_fastpath == EXIT_FASTPATH_CONT_RUN) { + vmx_sync_pir_to_irr(vcpu); goto cont_run; + } } return exit_fastpath; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index e7436d0..6a289d1 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4633,6 +4633,7 @@ struct kvm_vcpu *kvm_get_running_vcpu(void) return vcpu; } +EXPORT_SYMBOL_GPL(kvm_get_running_vcpu); /** * kvm_get_running_vcpus - get the per-CPU array of currently running vcpus. -- 2.7.4