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 5111EC2D0C6 for ; Thu, 12 Dec 2019 01:29:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 27D6D208C3 for ; Thu, 12 Dec 2019 01:29:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576114143; bh=cYxSv5bGUoIGqXO0c0d/IoNkTeKfqRsQsyJuL/YrLxs=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=bXarzjWhC5xzFAzT2Ma8rHVyb3h34BYuW5KDuCk6inSVICWJBi5/pXzIqT924jn0n RFJdoKorMEDWECNazDyDKZzB0GK7kUqH3ePgsoYtlkkiHworCPra9T7U6PnE99MV2p UfxH0bYjQZKjK5Dx5N4d8C8ixTOm/E4ukXq4OMmg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727461AbfLLB3C (ORCPT ); Wed, 11 Dec 2019 20:29:02 -0500 Received: from mail-lj1-f196.google.com ([209.85.208.196]:38773 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727351AbfLLB3B (ORCPT ); Wed, 11 Dec 2019 20:29:01 -0500 Received: by mail-lj1-f196.google.com with SMTP id k8so326930ljh.5 for ; Wed, 11 Dec 2019 17:29:00 -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 :cc; bh=ngCvhdELOgIQ69MigGwbslj0BoCyrEIfDMRe9lAU84c=; b=cwlWLXDtChisQx3BOxoqKRoI8l2aIzApJkZH0knnGXeRBkYyrjatj3Iqvq+pEYo8vz YB1Q6eIQ7M8Kp9xDL8IMabELBNs7kQEMnQVpm9+RvgFUWRjKay6CY/YEtmqENuN8NEJe SpgsA+0oAnSTBgoiasPVoSFTQm5OXTTIsNyTo= 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:cc; bh=ngCvhdELOgIQ69MigGwbslj0BoCyrEIfDMRe9lAU84c=; b=uTB4EzdKeWZ5dlAmiZQgxuBCvwAqAG6ZB5TUyJAtvNVBGeXGjAiJemq7V/2eR9F6NM U9EUJIPixYVbwK3rXA5e1C5EgQDd0cBFWFxrJ/TYIB0mGXj/gyBU6oCErovNCfhHnyh1 kOSsipdc5TFuZCu1La2dCHMsPo/tE8KONxesudv3D3qkoxr0jICH1twOqq5f9Z/OWa36 KL6QOCtuIhfNGm3V13Fw6HT/6/kmVwf1H3RJ12tN1BTbvoj626H/OFy28fMGbKSLYfMh T44Dw3FkOQ6AlJRpwKs2FQn7/BLT1rU/BddDEHaNKmHm0CtBb/fmjk2nEHiV8Cf5Y6w2 /z8Q== X-Gm-Message-State: APjAAAU+EP6aucx9AmuCBBvslGYncP4nZb0gb7j2SaTXdqZWPY27rIsO 0Z5VTZCwx+ETu/qs4HWMQPNMr3/SMec= X-Google-Smtp-Source: APXvYqy9R35PGK4ApW5ijXE0pZjtkt3MeCmI3lZWzaL1EZjZ2w5TTpsDeBqf8s+mpy0SPvazicR8KQ== X-Received: by 2002:a2e:8544:: with SMTP id u4mr4060216ljj.191.1576114138416; Wed, 11 Dec 2019 17:28:58 -0800 (PST) Received: from mail-lj1-f169.google.com (mail-lj1-f169.google.com. [209.85.208.169]) by smtp.gmail.com with ESMTPSA id s88sm2135277lje.64.2019.12.11.17.28.56 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 11 Dec 2019 17:28:57 -0800 (PST) Received: by mail-lj1-f169.google.com with SMTP id e28so309997ljo.9 for ; Wed, 11 Dec 2019 17:28:56 -0800 (PST) X-Received: by 2002:a05:651c:239:: with SMTP id z25mr4218712ljn.48.1576114136551; Wed, 11 Dec 2019 17:28:56 -0800 (PST) MIME-Version: 1.0 References: <157558502272.10278.8718685637610645781.stgit@warthog.procyon.org.uk> <20191206135604.GB2734@twin.jikos.cz> <9417.1576097731@warthog.procyon.org.uk> In-Reply-To: <9417.1576097731@warthog.procyon.org.uk> From: Linus Torvalds Date: Wed, 11 Dec 2019 17:28:40 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 0/2] pipe: Fixes [ver #2] To: David Howells Cc: David Sterba , Eric Biggers , Al Viro , linux-fsdevel , Linux Kernel Mailing List , Peter Zijlstra , Ingo Molnar , Vincent Guittot 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 Wed, Dec 11, 2019 at 12:55 PM David Howells wrote: > > Is it worth reverting: > > commit f94df9890e98f2090c6a8d70c795134863b70201 > Add wake_up_interruptible_sync_poll_locked() > > since you changed the code that was calling that new function and so it's no > longer called? You are sure you won't want that for the notification queue cases? I guess they'll never want to "sync" part.. Looking at the regular pipe read/write code, maybe we'll want to try it again - do the wakeup while we already have the spinlock, rather than later. But I have this suspicion that that might just then push things into mutex contention, so who knows.. Regardless, it's not going to happen for 5.5, so I guess we could revert it and if we ever end up trying it again we can resurrect it. Linus