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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9B936C433F5 for ; Thu, 3 Mar 2022 00:53:33 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C30A08D0002; Wed, 2 Mar 2022 19:53:32 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BDEFC8D0001; Wed, 2 Mar 2022 19:53:32 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ACD0A8D0002; Wed, 2 Mar 2022 19:53:32 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.a.hostedemail.com [64.99.140.24]) by kanga.kvack.org (Postfix) with ESMTP id 9ECB38D0001 for ; Wed, 2 Mar 2022 19:53:32 -0500 (EST) Received: from smtpin03.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 595A024D0A for ; Thu, 3 Mar 2022 00:53:32 +0000 (UTC) X-FDA: 79201251864.03.FBCF2CA Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) by imf19.hostedemail.com (Postfix) with ESMTP id 4E6B11A0005 for ; Thu, 3 Mar 2022 00:53:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:Content-Type :In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date:Message-ID: Sender:Reply-To:Content-ID:Content-Description; bh=CYkF4j9ODOf6PWDsqe5HpkOYKbyWN1x6jkFXxFgeeIM=; b=PIczBbwmNfBbdA0anRDnP9sLT/ D3I9C7NxiY8yS5fxYRvD+X1Y8NvnQsAJ6KbMn84+WnmOEZa+a3EleuPGwa0XtNrxd/DGw/ef1rtU1 3bIf2Ys5DyFChgu/ygcGG8BnMmFukl2vNmbxFArASFSZY6ZyT0XLRlLQa8fSBlXNPCjJoowfq4jS9 bp+QFItZn2MI13nEq4VGHgZejK9Npe9yw+z2aObmhsMYU9751wB+FsdPvNlHBJng2wtpaCJ5DwQqC lk3yguR7pD9mPkSib4B1IcaZyooSafWXX2OS9hQcj3fEAcyqabJ6+MSKUbxvAzcBFKIHSE/Qq0kaC PiXVDfqQ==; Received: from [2601:1c0:6280:3f0::aa0b] by desiato.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nPZif-00Eko6-Op; Thu, 03 Mar 2022 00:53:26 +0000 Message-ID: <9f8d4ddb-81ce-738a-d1f7-346ff9bf8ebd@infradead.org> Date: Wed, 2 Mar 2022 16:53:19 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH 1/2] mm/memcontrol: return 1 from cgroup.memory __setup() handler Content-Language: en-US To: =?UTF-8?Q?Michal_Koutn=c3=bd?= Cc: linux-mm@kvack.org, Igor Zhbanov , Andrew Morton , Johannes Weiner , Michal Hocko , Vladimir Davydov , cgroups@vger.kernel.org References: <20220222005811.10672-1-rdunlap@infradead.org> <20220302185300.GA19699@blackbody.suse.cz> From: Randy Dunlap In-Reply-To: <20220302185300.GA19699@blackbody.suse.cz> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 4E6B11A0005 X-Rspam-User: Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=infradead.org header.s=desiato.20200630 header.b=PIczBbwm; spf=none (imf19.hostedemail.com: domain of rdunlap@infradead.org has no SPF policy when checking 90.155.92.199) smtp.mailfrom=rdunlap@infradead.org; dmarc=none X-Stat-Signature: nr9b9zigtcgihbez8x5tdoxuhqpt6cp4 X-HE-Tag: 1646268811-981278 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 3/2/22 10:53, Michal Koutný wrote: > On Mon, Feb 21, 2022 at 04:58:11PM -0800, Randy Dunlap wrote: >> __setup() handlers should return 1 if the command line option is handled >> and 0 if not (or maybe never return 0; it just pollutes init's environment). > > Interesting. > >> Instead of relying on this '.' quirk, just return 1 to indicate that >> the boot option has been handled. > > But your patch would return 1 even when no accepted value was passed, > i.e. is the command line option considered handled in that case? Yes, for some definition of "handled." It was seen by the __setup handler. > Did you want to return 1 only when the cgroup.memory= value is > recognized? Not really. I did consider that (for all of the similar patches that I am posting). I don't think those strings (even with invalid option values) should be added to init's environment. I'm willing to add a pr_warn() or pr_notice() for any unrecognized option value, but it should still return 1 IMO. -- ~Randy