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=-0.9 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 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 3BED0C43603 for ; Sat, 7 Dec 2019 03:50:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 06CAD206DF for ; Sat, 7 Dec 2019 03:50:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575690631; bh=n8AidXnjky/A4JNuMfwLMIh44yi0Di/16P1CWY6x7LE=; h=References:In-Reply-To:From:Date:Subject:To:List-ID:From; b=dy99dX9VT8UUZX8JSw+KnFTi3ScRvrFwJgHVdFsUWcRJcPJkWroZBT9VaiHBsJwmL zimvv7c0RWW7QEAijIpi9e5QCiycf8HEEEL8JO1UdAUd7gml51OYEcrBVvwpzB5p5T HpOjDV3reU1jTILKssYCDQLVs8Z63VpD938e8ouI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726501AbfLGDua (ORCPT ); Fri, 6 Dec 2019 22:50:30 -0500 Received: from mail-lj1-f195.google.com ([209.85.208.195]:38086 "EHLO mail-lj1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726388AbfLGDu3 (ORCPT ); Fri, 6 Dec 2019 22:50:29 -0500 Received: by mail-lj1-f195.google.com with SMTP id k8so9771446ljh.5 for ; Fri, 06 Dec 2019 19:50:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=HEWM2qIddnPGufw5AQ6kyl6Y/Tjfdse09Yspvk/3RCI=; b=he2M8AdxCQFydLibVKShqyzikO8W2EI8NOK9ISS7ou9cfn0OpWBilIcQsB6NDgoNoq HKWi3kUP6tC/54/dKSqhFCoBdWpmni/VDi171bSieu2XDq+IZyrEDQTduR8PFfHiVvxK Esk5z6f8gqcxysY+UedwEvpN8S4uaS6yqV5Hs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=HEWM2qIddnPGufw5AQ6kyl6Y/Tjfdse09Yspvk/3RCI=; b=RUCvGLoOQFKEgDawdHJ8K/8PxP6i9MiFWaGDh7Ac/x/RoZk/waAYKQRU1Utd0BBKa5 w5D1j0FkIAuj1VrdhdJOmFyWvJUln0s20VO9wVrC0aJSbR/I25X7LUp/QmK0YtXc4tLn CgDL47/aousSp5IjNG+6SE9UeV4roooDCfYtfLQLT2WX51NWO2SeI+6kJsHA4K4Yr9IS +mQO3Z4MMpZNHuDugbxXqyEKV1cJrGuPOYRWOU5hN8P6a+Ui6hixEaM5Za0e9Zr1xAxO 90QzGMQBRyyYeZ497f/CGp9BX/BzD8i3CMECdnU+wFVl4V+cA2+bs+DleupunWFTM2wz d/EA== X-Gm-Message-State: APjAAAUeoI7cOHc+hDgzZhG2MCxnNAQYEl5LplMSavBtY8QtwChGj3zb QP0Qe3FmXmCOy79thexEB4Kv3dhPBzI= X-Google-Smtp-Source: APXvYqwE1ixrHdTY4o4msgBZC0FkhjkJZJHmLc5AHDaDCPmDvIcQ+WFRG0qBO0xPv4MpwIh22al+Gg== X-Received: by 2002:a2e:85c9:: with SMTP id h9mr2177532ljj.155.1575690626688; Fri, 06 Dec 2019 19:50:26 -0800 (PST) Received: from mail-lj1-f172.google.com (mail-lj1-f172.google.com. [209.85.208.172]) by smtp.gmail.com with ESMTPSA id a24sm7318990ljp.97.2019.12.06.19.50.25 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 06 Dec 2019 19:50:25 -0800 (PST) Received: by mail-lj1-f172.google.com with SMTP id a13so9758738ljm.10 for ; Fri, 06 Dec 2019 19:50:25 -0800 (PST) X-Received: by 2002:a2e:9ad8:: with SMTP id p24mr7759167ljj.148.1575690624637; Fri, 06 Dec 2019 19:50:24 -0800 (PST) MIME-Version: 1.0 References: <157558502272.10278.8718685637610645781.stgit@warthog.procyon.org.uk> <20191206135604.GB2734@twin.jikos.cz> In-Reply-To: From: Linus Torvalds Date: Fri, 6 Dec 2019 19:50:08 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 0/2] pipe: Fixes [ver #2] To: David Sterba , David Howells , Linus Torvalds , Eric Biggers , Al Viro , linux-fsdevel , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 6, 2019 at 1:04 PM Linus Torvalds wrote: > > It doesn't fix my "kernel compiles go single-threaded" issue. I ended up just bisecting it. The "make goes slow" problem bisects down to b667b8673443 ("pipe: Advance tail pointer inside of wait spinlock in pipe_read()"). I assume it's the added "do_wakeup = 0" (not the spinlock) that ends up having some subtle issue. Very strange, but there it is. Linus