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=-2.5 required=3.0 tests=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 00ADEC0650E for ; Wed, 3 Jul 2019 14:13:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D86DD218A4 for ; Wed, 3 Jul 2019 14:13:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726768AbfGCONd (ORCPT ); Wed, 3 Jul 2019 10:13:33 -0400 Received: from mail-wm1-f67.google.com ([209.85.128.67]:35265 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726473AbfGCONd (ORCPT ); Wed, 3 Jul 2019 10:13:33 -0400 Received: by mail-wm1-f67.google.com with SMTP id c6so2593714wml.0 for ; Wed, 03 Jul 2019 07:13:31 -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=ceMV6gREtUAH3s1rcTbUar/B6JUKROFXvDiwuyYeGXY=; b=uSdOMlUAtdsDX86GBHurLjx7QTv00KroQoREgWMEzTZqQGaXn6pcoiN1gI0ysTAjxs 6e8Lgp1TdvSvKKTnUw7GHKsuBlXxmOQrwVliFXhrppef3txqA/RIMVEr6RcU7x9obRfK hifDxWGrh6qY8hA3fJaPLezoYcY8pSAjsR9q4wdT3Vpvreaz3WRlMN1WmAlWZQ6oCJGY RGeUNtKIKGQvrk3wojfNZftJzdG6oYYCMmtSXrgraJu26dOzM2tpkh7TmabnTAqI4uO+ +iy3zmicS/3SW7k2rboXg8uudpPxzKBGUPLV984hpzGW2vNzv60z3HCjk8sybTDHKDvi iCow== X-Gm-Message-State: APjAAAV1ZgkJ22ZquRTBV1au/3Iz+9i0jSbE60b+scohqcde5t+7JwEL m2OrNhSaB1Sgz6LdnLbseGtxLw== X-Google-Smtp-Source: APXvYqzNc25USnquIIueAfxvqHocNLi2CDXyM4EEc7JEs2GM3KQJc87l+CG6bfH/8feI9wY5hiX4JA== X-Received: by 2002:a7b:cb08:: with SMTP id u8mr8054265wmj.167.1562163210995; Wed, 03 Jul 2019 07:13:30 -0700 (PDT) Received: from ?IPv6:2001:b07:6468:f312:6c1d:63cc:b81d:e1a9? ([2001:b07:6468:f312:6c1d:63cc:b81d:e1a9]) by smtp.gmail.com with ESMTPSA id o4sm2442172wmh.35.2019.07.03.07.13.30 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Wed, 03 Jul 2019 07:13:30 -0700 (PDT) Subject: Re: [PATCH v4 1/2] KVM: LAPIC: Optimize timer latency consider world switch time To: Wanpeng Li , LKML , kvm Cc: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , Sean Christopherson References: <1560474949-20497-1-git-send-email-wanpengli@tencent.com> <1560474949-20497-2-git-send-email-wanpengli@tencent.com> From: Paolo Bonzini Message-ID: <18fd2372-45d8-0bff-79e7-373a8b7d129c@redhat.com> Date: Wed, 3 Jul 2019 16:13:29 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On 03/07/19 02:48, Wanpeng Li wrote: > Hi Paolo, how about this patchset? Patch 2/2 is easy to take, do you > have more concern about patch 1/2? I don't know. It seems somewhat hard to tune and in cyclictest it only happens for preemption_timer=N. Are you using preemption_timer=N together with the LAPIC-timer-on-service-CPU patches? Paolo