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=-3.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 CE2F1C282C3 for ; Thu, 24 Jan 2019 17:01:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9E8F5218C3 for ; Thu, 24 Jan 2019 17:01:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548349282; bh=IdaIj0dltWsxNzjiO9YjwH5bB4s5zU9bg3u2IoXgZ/M=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=qJk3kLZjf8LG1j4LvlXsf0CtoxpNk+Vr1ZYsOYnN1DifixJvbFAKJ2MIf+JZq8Fc6 jsCOTOLO1mp5ox77M389uzJ+3HzLqXl6RkXM1OqWCRCWP3HsA5Cg1IuDk6LUwsuL55 CSr7xwolhLy+uetKC1NPS/qv+ZndQrxyLlAyFj3A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728668AbfAXRBU (ORCPT ); Thu, 24 Jan 2019 12:01:20 -0500 Received: from mx2.suse.de ([195.135.220.15]:43436 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727443AbfAXRBU (ORCPT ); Thu, 24 Jan 2019 12:01:20 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 12A1EAFCC; Thu, 24 Jan 2019 17:01:19 +0000 (UTC) Date: Thu, 24 Jan 2019 18:01:17 +0100 From: Michal Hocko To: Johannes Weiner Cc: Chris Down , Andrew Morton , Tejun Heo , Roman Gushchin , Dennis Zhou , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, kernel-team@fb.com Subject: Re: [PATCH 2/2] mm: Consider subtrees in memory.events Message-ID: <20190124170117.GS4087@dhcp22.suse.cz> References: <20190123223144.GA10798@chrisdown.name> <20190124082252.GD4087@dhcp22.suse.cz> <20190124160009.GA12436@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190124160009.GA12436@cmpxchg.org> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu 24-01-19 11:00:10, Johannes Weiner wrote: [...] > We cannot fully eliminate a risk for regression, but it strikes me as > highly unlikely, given the extremely young age of cgroup2-based system > management and surrounding tooling. I am not really sure what you consider young but this interface is 4.0+ IIRC and the cgroup v2 is considered stable since 4.5 unless I missrememeber and that is not a short time period in my book. Changing interfaces now represents a non-trivial risk and so far I haven't heard any actual usecase where the current semantic is actually wrong. Inconsistency on its own is not a sufficient justification IMO. -- Michal Hocko SUSE Labs