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=MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT 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 DEECCC43143 for ; Fri, 22 Jun 2018 13:10:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A368A24277 for ; Fri, 22 Jun 2018 13:10:21 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A368A24277 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754140AbeFVNKT (ORCPT ); Fri, 22 Jun 2018 09:10:19 -0400 Received: from mx2.suse.de ([195.135.220.15]:52042 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750999AbeFVNKP (ORCPT ); Fri, 22 Jun 2018 09:10:15 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext-too.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 75E16ACF3; Fri, 22 Jun 2018 13:10:14 +0000 (UTC) Date: Fri, 22 Jun 2018 15:10:13 +0200 From: Michal Hocko To: Mikulas Patocka Cc: jing xia , Mike Snitzer , agk@redhat.com, dm-devel@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: dm bufio: Reduce dm_bufio_lock contention Message-ID: <20180622131013.GA10465@dhcp22.suse.cz> References: <20180615073201.GB24039@dhcp22.suse.cz> <20180615115547.GH24039@dhcp22.suse.cz> <20180615130925.GI24039@dhcp22.suse.cz> <20180619104312.GD13685@dhcp22.suse.cz> <20180622090151.GS10465@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.5 (2018-04-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 22-06-18 08:44:52, Mikulas Patocka wrote: > On Fri, 22 Jun 2018, Michal Hocko wrote: [...] > > Why? How are you going to audit all the callers that the behavior makes > > sense and moreover how are you going to ensure that future usage will > > still make sense. The more subtle side effects gfp flags have the harder > > they are to maintain. > > I did audit them - see the previous email in this thread: > https://www.redhat.com/archives/dm-devel/2018-June/thread.html I do not see any mention about throttling expectations for those users. You have focused only on the allocation failure fallback AFAIR -- Michal Hocko SUSE Labs