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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 E130FC43381 for ; Tue, 26 Feb 2019 17:48:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BAE3F2173C for ; Tue, 26 Feb 2019 17:48:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728801AbfBZRsP (ORCPT ); Tue, 26 Feb 2019 12:48:15 -0500 Received: from mail-pg1-f196.google.com ([209.85.215.196]:36937 "EHLO mail-pg1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727624AbfBZRsP (ORCPT ); Tue, 26 Feb 2019 12:48:15 -0500 Received: by mail-pg1-f196.google.com with SMTP id q206so6556837pgq.4 for ; Tue, 26 Feb 2019 09:48:15 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:mime-version:content-transfer-encoding; bh=Z/FSmsA/f1QwcU9WmykfUtdlf6vIpFkEAGHYFfGCxhk=; b=YU8MDbwglJMrOIXdf0jOUBxPiB7OXL83Ff0w9+cHmhvD6xS7fre0zEFKxHKdr8n5yb qTloT/FukVpbgFnmMkXPS7TX+bdu13YOOjt6N/stBnU8/k3bZFhtdrEJ3N/pDJdR0Dyn Lj4+Az9m8Jqf0XRLbAEdWllgEdFP+XnOIOwZMBIjvNWYtI8AFrX0vf2LOtELmAEUh+4B fpZWCaZqaQZDYXRmxrIKCGEkbLK+7TaBclbuOPU2HasMVL28O7mNP/xGVlhaL/kbx8lT oyNI+ZCjky4vspO7hFGvOhfzfOpI7ugBoNzzcqkHkDI4cF39i+ebhre1PDz4V1lnDHJO Kmhw== X-Gm-Message-State: AHQUAuZBe1/XwkbqrLFDxpXNl8bJjZ9qt3VFAM3IiLrC1jrjUfaMNgWC HYgRZ7ArH9sx6ujDVBYihho= X-Google-Smtp-Source: AHgI3IZTypfmbiDR2AMD+mlVWRYiApNFJGSmfWACf9bA0TGbo/apexQpufSLDj8Plxs2Mzm/LAuD4A== X-Received: by 2002:a63:112:: with SMTP id 18mr24468142pgb.139.1551203294737; Tue, 26 Feb 2019 09:48:14 -0800 (PST) Received: from ?IPv6:2620:15c:2cd:203:5cdc:422c:7b28:ebb5? ([2620:15c:2cd:203:5cdc:422c:7b28:ebb5]) by smtp.gmail.com with ESMTPSA id 4sm33882964pft.96.2019.02.26.09.48.13 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 26 Feb 2019 09:48:13 -0800 (PST) Message-ID: <1551203292.31902.174.camel@acm.org> Subject: Re: [PATCH v7 21/23] block: Avoid that flushing triggers a lockdep complaint From: Bart Van Assche To: Peter Zijlstra Cc: mingo@redhat.com, will.deacon@arm.com, tj@kernel.org, longman@redhat.com, johannes.berg@intel.com, linux-kernel@vger.kernel.org, Jens Axboe , Ming Lei , Theodore Ts'o Date: Tue, 26 Feb 2019 09:48:12 -0800 In-Reply-To: <20190226172421.GI32494@hirez.programming.kicks-ass.net> References: <20190214230058.196511-1-bvanassche@acm.org> <20190214230058.196511-22-bvanassche@acm.org> <20190226172421.GI32494@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-7" X-Mailer: Evolution 3.26.2-1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2019-02-26 at 18:24 +-0100, Peter Zijlstra wrote: +AD4 On Thu, Feb 14, 2019 at 03:00:56PM -0800, Bart Van Assche wrote: +AD4 +AD4 +AEAAQA -472,7 +-473,8 +AEAAQA struct blk+AF8-flush+AF8-queue +ACo-blk+AF8-alloc+AF8-flush+AF8-queue(struct request+AF8-queue +ACo-q, +AD4 +AD4 if (+ACE-fq) +AD4 +AD4 goto fail+ADs +AD4 +AD4 +AD4 +AD4 - spin+AF8-lock+AF8-init(+ACY-fq-+AD4-mq+AF8-flush+AF8-lock)+ADs +AD4 +AD4 +- lockdep+AF8-register+AF8-key(+ACY-fq-+AD4-key)+ADs +AD4 +AD4 +- spin+AF8-lock+AF8-init+AF8-key(+ACY-fq-+AD4-mq+AF8-flush+AF8-lock, +ACY-fq-+AD4-key)+ADs +AD4 +AD4 What's wrong with: +AD4 +AD4 spin+AF8-lock+AF8-init(+ACY-fq-+AD4-wq+AF8-flush+AF8-lock)+ADs +AD4 lockdep+AF8-register+AF8-key(+ACY-fq-+AD4-key)+ADs +AD4 lockdep+AF8-set+AF8-class(+ACY-fq-+AD4-wq+AF8-flush+AF8-lock, +ACY-fq-+AD4-key)+ADs +AD4 +AD4 ? Hi Peter, That's an approach that I had not yet considered. I'm fine with the lockdep+AF8-set+AF8-class() version. Bart.