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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 29A3BC433EF for ; Tue, 19 Oct 2021 19:51:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 80D1A610CC for ; Tue, 19 Oct 2021 19:51:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 80D1A610CC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 096A76B006C; Tue, 19 Oct 2021 15:51:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 020426B0071; Tue, 19 Oct 2021 15:51:51 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E2A2F900002; Tue, 19 Oct 2021 15:51:51 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0190.hostedemail.com [216.40.44.190]) by kanga.kvack.org (Postfix) with ESMTP id D20866B006C for ; Tue, 19 Oct 2021 15:51:51 -0400 (EDT) Received: from smtpin07.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 8EC233C7A4 for ; Tue, 19 Oct 2021 19:51:51 +0000 (UTC) X-FDA: 78714232422.07.710EE42 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf26.hostedemail.com (Postfix) with ESMTP id 3949F20019D3 for ; Tue, 19 Oct 2021 19:51:52 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id D30336113B; Tue, 19 Oct 2021 19:51:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1634673110; bh=jGj86H0JaCzg0FpU/IIjOqXur5MOCHmg5HVDErAlS9c=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=TE+8q5G6fg7FTvw+yGNn9m1udm/EaXQQxjSdnl2DK2j9ru/LUmoehpNnHbrC3ahjC L3ozhy5L4vY9OfwgTE/VfwTdlx7EA2Oi0pPjdAPUIGoqSfE9cYyVqOgIumoSSkTTZc rqu3KbK+HyM8WLPftcSg3LwtyGTSq5mEdyEezJdg= Date: Tue, 19 Oct 2021 12:51:47 -0700 From: Andrew Morton To: Shakeel Butt Cc: Johannes Weiner , Michal Hocko , Vasily Averin , Roman Gushchin , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Michal Hocko , Muchun Song Subject: Re: [PATCH v3] memcg, kmem: further deprecate kmem.limit_in_bytes Message-Id: <20211019125147.0ad010f318bbd8233cadcdae@linux-foundation.org> In-Reply-To: <20211019153408.2916808-1-shakeelb@google.com> References: <20211019153408.2916808-1-shakeelb@google.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 3949F20019D3 Authentication-Results: imf26.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=TE+8q5G6; spf=pass (imf26.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-Stat-Signature: e3mpzswu4pn3jubd9uqpa3fm59teajps X-Rspamd-Server: rspam05 X-HE-Tag: 1634673112-959729 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 Tue, 19 Oct 2021 08:34:08 -0700 Shakeel Butt wrote: > The deprecation process of kmem.limit_in_bytes started with the commit > 0158115f702 ("memcg, kmem: deprecate kmem.limit_in_bytes") which also > explains in detail the motivation behind the deprecation. To summarize, > it is the unexpected behavior on hitting the kmem limit. This patch > moves the deprecation process to the next stage by disallowing to set > the kmem limit. In future we might just remove the kmem.limit_in_bytes > file completely. > > ... > > @@ -3791,10 +3766,8 @@ static ssize_t mem_cgroup_write(struct kernfs_open_file *of, > ret = mem_cgroup_resize_max(memcg, nr_pages, true); > break; > case _KMEM: > - pr_warn_once("kmem.limit_in_bytes is deprecated and will be removed. " > - "Please report your usecase to linux-mm@kvack.org if you " > - "depend on this functionality.\n"); > - ret = memcg_update_kmem_max(memcg, nr_pages); > + /* kmem.limit_in_bytes is deprecated. */ > + ret = -ENOTSUPP; > break; > case _TCP: > ret = memcg_update_tcp_max(memcg, nr_pages); checkpatch said "ENOTSUPP is not a SUSV4 error code, prefer EOPNOTSUPP"?