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=unavailable 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 2CDF7C10F05 for ; Fri, 29 Mar 2019 16:44:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE81421871 for ; Fri, 29 Mar 2019 16:44:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729736AbfC2QoP (ORCPT ); Fri, 29 Mar 2019 12:44:15 -0400 Received: from mail02.iobjects.de ([188.40.134.68]:46076 "EHLO mail02.iobjects.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729150AbfC2QoP (ORCPT ); Fri, 29 Mar 2019 12:44:15 -0400 Received: from tux.wizards.de (pD9EBF050.dip0.t-ipconnect.de [217.235.240.80]) by mail02.iobjects.de (Postfix) with ESMTPSA id 7FD264164E66; Fri, 29 Mar 2019 17:44:13 +0100 (CET) Received: from [192.168.100.223] (ragnarok.applied-asynchrony.com [192.168.100.223]) by tux.wizards.de (Postfix) with ESMTP id 4D335F01606; Fri, 29 Mar 2019 17:44:13 +0100 (CET) Subject: Re: [PATCH] block/bfq: fix ifdef for CONFIG_BFQ_GROUP_IOSCHED=y To: Jens Axboe , Konstantin Khlebnikov , linux-block@vger.kernel.org, Paolo Valente , linux-kernel@vger.kernel.org References: <155386807826.3190.16175453392005064129.stgit@buzz> <5234a971-2b6a-47b1-0071-8f3bd07d9fc3@kernel.dk> <6be15f08-dbb4-6b43-3d95-44044f1acdbc@kernel.dk> From: =?UTF-8?Q?Holger_Hoffst=c3=a4tte?= Organization: Applied Asynchrony, Inc. Message-ID: <3c87a84f-9fb2-2407-a5a3-723b314d8e58@applied-asynchrony.com> Date: Fri, 29 Mar 2019 17:44:13 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <6be15f08-dbb4-6b43-3d95-44044f1acdbc@kernel.dk> Content-Type: text/plain; charset=utf-8; format=flowed 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 3/29/19 5:15 PM, Jens Axboe wrote: >>>> Good catch! I run without group scheduling and therefore didn't notice these >>>> stray defines earlier. For 5.1 it should merge cleanly; adding this on top of >>>> the pending 5.2 BFQ patches required a small context fixup in hunk #1 due to >>>> "block, bfq: do not idle for lowest-weight queues". >>> >>> I'm hesitant to apply this, since the group scheduling stuff has obviously never >>> been tested. >> >> This is simply a regression in 5.1 caused by 73d58118498b - nothing else, >> and as such this fix needs to go into 5.1 as well. I'm sure Paolo will agree. >> What you so ominously call "the group scheduling stuff" has been there and >> shipping in mainline since day 1 of the BFQ merge, and it works fine in 5.0. > > If that's the case (I didn't check how far back it went), then yes, it should > of course go into 5.1. Yay. > The ominous nature of my reply I'll chalk up to your interpretation Fair enough ;) A more interesting question is why upstream uses undefined defines for patches. That's a first-rate self-grenade if I've ever seen one, and obviously something that is easily missed. Paolo? -h