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 BFCF2C83000 for ; Tue, 28 Apr 2020 06:24:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9A3BE206B9 for ; Tue, 28 Apr 2020 06:24:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="sFxQQzq7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726573AbgD1GYJ (ORCPT ); Tue, 28 Apr 2020 02:24:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726474AbgD1GXz (ORCPT ); Tue, 28 Apr 2020 02:23:55 -0400 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 80887C03C1A9; Mon, 27 Apr 2020 23:23:54 -0700 (PDT) Received: by mail-pg1-x544.google.com with SMTP id d17so9841238pgo.0; Mon, 27 Apr 2020 23:23:54 -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=c4J23pfnjE51eiU8sg/gmUkqucxcbnJvyvaM93YyDy8=; b=sFxQQzq7Mg0a9LVrigkvsGpOutFd3UmHoo7YxqEc2e/CIwse9vEG3VCe7dlSVMd1L4 Nx6zQZnhL6FYfDXT/LCne37szpqNofdNRrF4qmXnkj5chX5NTOffEyRfGNOOXVHXZevb ORWL45so9Q2uygWze4TlTfFtszIpZdZvshtJ2KfNTBif1kUgfo++tH58p4v0GANSsxzQ zY2CvFKWMse6vlPklFz/Im0M6bQtEih/bf/3rLadg6+MjlecQ34l4bS2EZMiBQgxgBn1 CGgCupke1j5ye0TR7e6x+Toq+OyzFAPeSnlltPImbAPfPqNN2LqGlUnpIfdSMcOvzCuO R2Qg== 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=c4J23pfnjE51eiU8sg/gmUkqucxcbnJvyvaM93YyDy8=; b=VhnrXwqa+nduBNewuI71cg6Bi81E33uWdGxvgja1i8SxgFmzQu56cA5JeLO9lcW+GM FjJooivYrdjJIE6J495LCL4cb/mwKoCS3c5xXNwV/iprfgEphHKAL6FCkNlq+sY7z+Gt YqvRCX1UIeY5pfy1X4EZ7rBopty7EYMl4Virv5WzeH1ptnUrvRvdl3zpliQKYnXug+UT BnF9/pN60riVNoJYnOl2tv3Nj65H8mbjpfd3yIAoz2hiLvaUIgtZM2imX/S+6sw6mBqh Skz024W+fsFoRZMqihNrwMff/GGYU2XMPhTdoZ222qUHTvkABSaqUnXJPgm0v1f8EUgE kyuA== X-Gm-Message-State: AGi0PuZuBhkKGC71fQL4y0bOphoYh+IB9JJFnIdbZmJqRpxaAtLQ5I4G GZ/kVqA4PlAuP0B1TyySID3KrhIl X-Google-Smtp-Source: APiQypLQMmro+DQJ5c5SblXXuHsVr5QFrpUVoA0Jh34UQ6ckiRrL94Euwh7qSKyy+M/FsCUJccvn9g== X-Received: by 2002:a62:4d43:: with SMTP id a64mr30288672pfb.156.1588055033511; Mon, 27 Apr 2020 23:23:53 -0700 (PDT) Received: from localhost.localdomain ([103.7.29.6]) by smtp.googlemail.com with ESMTPSA id u188sm14183071pfu.33.2020.04.27.23.23.51 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 27 Apr 2020 23:23:53 -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 v4 5/7] KVM: VMX: Optimize posted-interrupt delivery for timer fastpath Date: Tue, 28 Apr 2020 14:23:27 +0800 Message-Id: <1588055009-12677-6-git-send-email-wanpengli@tencent.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1588055009-12677-1-git-send-email-wanpengli@tencent.com> References: <1588055009-12677-1-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 reenter guest. Tested-by: Haiwei Li Cc: Haiwei Li Signed-off-by: Wanpeng Li --- arch/x86/kvm/vmx/vmx.c | 12 ++++++++---- virt/kvm/kvm_main.c | 1 + 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 24cadf4..ce19b0e 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -3909,7 +3909,8 @@ 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)) + if (vcpu != kvm_get_running_vcpu() && + !kvm_vcpu_trigger_posted_interrupt(vcpu, false)) kvm_vcpu_kick(vcpu); return 0; @@ -6777,9 +6778,12 @@ static fastpath_t vmx_vcpu_run(struct kvm_vcpu *vcpu) vmx_complete_interrupts(vmx); exit_fastpath = vmx_exit_handlers_fastpath(vcpu); - if (exit_fastpath == EXIT_FASTPATH_REENTER_GUEST && - kvm_vcpu_exit_request(vcpu)) - exit_fastpath = EXIT_FASTPATH_NOP; + if (exit_fastpath == EXIT_FASTPATH_REENTER_GUEST) { + if (!kvm_vcpu_exit_request(vcpu)) + vmx_sync_pir_to_irr(vcpu); + else + exit_fastpath = EXIT_FASTPATH_NOP; + } return exit_fastpath; } diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 33e1eee..2482f3c 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -4644,6 +4644,7 @@ 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