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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 BD091C2BA19 for ; Thu, 23 Apr 2020 09:41:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9528C2076C for ; Thu, 23 Apr 2020 09:41:19 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="EKGNSNHz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727009AbgDWJlS (ORCPT ); Thu, 23 Apr 2020 05:41:18 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:60414 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726343AbgDWJlS (ORCPT ); Thu, 23 Apr 2020 05:41:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1587634877; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=azl4EOKrk5ieu/X3rC1ejOH/OCp4GqTP+vS6TG0Ikm0=; b=EKGNSNHzdn910QtysBG+jUTJj05EHFgXatnTcLIXVUkIejJtchvoxUv92jGSUH6PPVfh+W ifSrncinOyDXQcf6af6evlaUIPmCedIMrq8rwZQJY4JI+/XMCJu8p103Dh1Fi0cCe41lkb rJeO48qJ8zx51IDuOQ8WA4dlsoa8jFk= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-418-F539PVjpMOO15hY5ToiJjQ-1; Thu, 23 Apr 2020 05:41:15 -0400 X-MC-Unique: F539PVjpMOO15hY5ToiJjQ-1 Received: by mail-wm1-f72.google.com with SMTP id l21so1858396wmh.2 for ; Thu, 23 Apr 2020 02:41:15 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=azl4EOKrk5ieu/X3rC1ejOH/OCp4GqTP+vS6TG0Ikm0=; b=btPp/ApB2f+ipIPto+bkLFtIziPbN+uDDXaThmFLWOCeFFD54WsolVDqdHmU6+BEbc m5WlkZySanAWpEafJ3eoDWoagnzW4YAeT/UwKNqDj0oQtrJXlMc13v0XnFpLOH+hkY2m Y4T7gK1lWEPRehwEdjbMvuQt9sXLsviGvFzzHf7OVeEeJh/CNWowCns8JNHxxKoqfSoh 9MXlfUMlJn5PzwRaYeBzUmtXStTiw5zy0B/7o+/ITzn2swwRTJeD5MtSC2f50029Ak5w J7KsURkNeAD+uiaUi8wPBRA/2wvoHG+jXftVCPry+PgT9aNwg/AxmImMIhvOb/6zMQQr 22sw== X-Gm-Message-State: AGi0PuY4aCHPpO1Qs0HFGVrq4DlAAXmIfBh9MC700JoPnr2WXD5FKwrA IIjgrzImupmf1COL+sA0NlozBp6M3V640tYZecuQxZhhucjS6iFOHOeJp9LEXZXGIeRT4x7N3rr WSu0xGlf7unSk5zvxPyxskTIs X-Received: by 2002:a5d:4645:: with SMTP id j5mr3833208wrs.282.1587634873996; Thu, 23 Apr 2020 02:41:13 -0700 (PDT) X-Google-Smtp-Source: APiQypKmS21JtTUsn1ahG9txOKjxAk/HDnRTv0ERS+dV5m610jdf8hdz/jbKFEmKVINrb0EQb/vgsA== X-Received: by 2002:a5d:4645:: with SMTP id j5mr3833184wrs.282.1587634873822; Thu, 23 Apr 2020 02:41:13 -0700 (PDT) Received: from [192.168.10.150] ([93.56.170.5]) by smtp.gmail.com with ESMTPSA id h188sm3135576wme.8.2020.04.23.02.41.12 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 23 Apr 2020 02:41:13 -0700 (PDT) Subject: Re: [PATCH v2 1/5] KVM: LAPIC: Introduce interrupt delivery fastpath To: Wanpeng Li Cc: LKML , kvm , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Haiwei Li References: <1587632507-18997-1-git-send-email-wanpengli@tencent.com> <1587632507-18997-2-git-send-email-wanpengli@tencent.com> <09cba36c-61d8-e660-295d-af54ceb36036@redhat.com> From: Paolo Bonzini Message-ID: <8a29181c-c6bb-fe36-51ac-49d764819393@redhat.com> Date: Thu, 23 Apr 2020 11:39:02 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 23/04/20 11:35, Wanpeng Li wrote: >> Ok, got it now. The problem is that deliver_posted_interrupt goes through >> >> if (!kvm_vcpu_trigger_posted_interrupt(vcpu, false)) >> kvm_vcpu_kick(vcpu); >> >> Would it help to make the above >> >> if (vcpu != kvm_get_running_vcpu() && >> !kvm_vcpu_trigger_posted_interrupt(vcpu, false)) >> kvm_vcpu_kick(vcpu); >> >> ? If that is enough for the APICv case, it's good enough. > We will not exit from vmx_vcpu_run to vcpu_enter_guest, so it will not > help, right? Oh indeed---the call to sync_pir_to_irr is in vcpu_enter_guest. You can add it to patch 3 right before "goto cont_run", since AMD does not need it. Paolo