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 04772C3DA4A for ; Wed, 14 Aug 2024 22:58:11 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 801346B0099; Wed, 14 Aug 2024 18:58:11 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 78A6D6B009A; Wed, 14 Aug 2024 18:58:11 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 62AD66B009B; Wed, 14 Aug 2024 18:58:11 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 430F86B0099 for ; Wed, 14 Aug 2024 18:58:11 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id DD500161164 for ; Wed, 14 Aug 2024 22:58:10 +0000 (UTC) X-FDA: 82452365940.19.1AE008F Received: from mail-yb1-f175.google.com (mail-yb1-f175.google.com [209.85.219.175]) by imf25.hostedemail.com (Postfix) with ESMTP id 0AD76A0003 for ; Wed, 14 Aug 2024 22:58:07 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=WnNSInmF; spf=pass (imf25.hostedemail.com: domain of tjmercier@google.com designates 209.85.219.175 as permitted sender) smtp.mailfrom=tjmercier@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1723676216; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=cg2m0Y0MLRB7Avk9yfRLo8H0fSSwKpXrdO3LFcvmAyE=; b=fh3ZIuPzCwhySoED9x6TscSZW1RGrWw66N3vnpg/SYOOvkpt9Z8CnZOTgt52jGM2kXiS1b i8n/8Wh3EY+dffmNQNVpPAjTcwiKtG6tl8xN13/7I5I3qZ31oAUfW/E6gd/C7vq6PQQucw zyU5VWeX8clCvH0CRJUuz2g/jOCNFSI= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1723676216; a=rsa-sha256; cv=none; b=UmMBwYWjtxBQXJP6dXuhGL74QXEPCboT6IcP0CoYjVWy/VcyZx9/Wrw82nRMfO1dCYceee nYDf24SvhGncK3854PskhNV+4Fp+CkkJtvOT1GDjFv5CxGiuVJLE9ZbCkLikPLFsrfw9Bt +5kTscv61aiK06WQIS1dWD56KWC6Gaw= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=WnNSInmF; spf=pass (imf25.hostedemail.com: domain of tjmercier@google.com designates 209.85.219.175 as permitted sender) smtp.mailfrom=tjmercier@google.com; dmarc=pass (policy=reject) header.from=google.com Received: by mail-yb1-f175.google.com with SMTP id 3f1490d57ef6-e116d2f5f7fso329178276.1 for ; Wed, 14 Aug 2024 15:58:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1723676287; x=1724281087; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=cg2m0Y0MLRB7Avk9yfRLo8H0fSSwKpXrdO3LFcvmAyE=; b=WnNSInmFCWXbxU782Xan96ABy3BtPDf3CL09b/004JcnUx/NBlAGI2EJzohD6P73Eb 84lOnT6CHm+CYnrW+onN1cF+pkZaL0GM2VvSkm7Yy4F6qZT2X/C2CEEcNm9jiti0X5tD YFvfM29pTRdysUBW0WdfbuA2w8xlDgRAYpaB0jd2c+SQAjKiVyPBv91wsoqTAONvx97b LYC4frVcEbxDZZmsUE6lC5APCQtoX/MU0NFc/RcljT2IFme20nLlOARAjUBSW6WuB0mS 345gXIfsDFyuG7UteVQC0Bs4OvP3rySMPV3Je6rGHoxAYIr/x3AhjBsOHYMIZgV9zP2v BMsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723676287; x=1724281087; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=cg2m0Y0MLRB7Avk9yfRLo8H0fSSwKpXrdO3LFcvmAyE=; b=jy1ZvsH9elMtp9WMbJUB0gt4P1cN8cK35ZdraAzPzRrjVW2+uXgIvu0tvETr3Xi+3H hgZ/VqOCebUM7YhxQt5PcQ5oMzI6OWcD6Y9tvaV50LvbydsF+Y0IKXAXGqLfZX2wE5I1 I5EaQ2eKbC7pVVms43Lx4aQq0oYI9K1WCuU7n6a6RVxwtvIXGxrbyyaTqP75E5yxIuKU q0uj5EujaIgTN7u7w9uiAdqocqOINoy8KOuuz4qWda9fZ5ZpaaMp1tys7PcP1YkcLB8+ dp1b7ZTBPWQjiX47VdTBeStAR4JmgTA9VBwXkUkVwIREvVeYy+RHKzrvdD3fu6tD+MRJ Id3A== X-Forwarded-Encrypted: i=1; AJvYcCXn2+RMlsbt1JX37OjS3KMk/uD4c0ZaeVeB7M9C8JuisK9TzhNMhmIg9riWh9bs5hBX9yfHfqZeOiD+u+5RfAFF8uE= X-Gm-Message-State: AOJu0YwIEDBRviuOC/8OhRwQJDhJqVaDhJgj2ACpoyCsn6oVH3Jnt0J/ zVEjhY1e+ItQb2cpRZFSuxSts1mJhuhlT7ffBgRGTohmZQzH9aLlr1h9dbTBWKuRlZNq+goGl6r /cfuCFtHH+Y4W0xEIGCqPthh1/zDiFmpIcR01 X-Google-Smtp-Source: AGHT+IGE3OvVYyMYXkHkGJ1LSwjpNsAdugkc/con7/60JcJ4IkohU717cj0tGtSNLqUJ8SRDWSiXbwmKw4ZrDuLrhI0= X-Received: by 2002:a05:6902:d4a:b0:e11:48d6:a437 with SMTP id 3f1490d57ef6-e116cc4aee0mr1359570276.2.1723676286771; Wed, 14 Aug 2024 15:58:06 -0700 (PDT) MIME-Version: 1.0 References: <20240814220021.3208384-1-shakeel.butt@linux.dev> <20240814220021.3208384-3-shakeel.butt@linux.dev> In-Reply-To: <20240814220021.3208384-3-shakeel.butt@linux.dev> From: "T.J. Mercier" Date: Wed, 14 Aug 2024 15:57:54 -0700 Message-ID: Subject: Re: [PATCH v2 2/4] memcg: initiate deprecation of v1 soft limit To: Shakeel Butt Cc: Andrew Morton , Johannes Weiner , Michal Hocko , Roman Gushchin , Muchun Song , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Meta kernel team , cgroups@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 0AD76A0003 X-Stat-Signature: er6u6wpjfoz8iagcygfp1ychbkcw43jk X-Rspamd-Server: rspam09 X-Rspam-User: X-HE-Tag: 1723676287-817879 X-HE-Meta: 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 ulgLlfWG mp9tOlU3SAx6vlRGrSDxa5ZnCeq71NAu+NcnxRdRqLYT3BmLatmZQgRuXQ3Vuh91TyTfPI62mNCu00I2cZ2g1PYQmAfQeANLfrGBxqBvPJGVBYiriH7XfmEJD5+22IPmrqYFWQt4M+25ifsVJ2j9aJYKGJ4vTF46DXl0OSMHmj5rlO+g7TH/F9c+yq4vihjyrPehkOKBgjC8ZCa1ABq+kiufWMeR/NMMazlKhoohFK9LBuYkiH5U+wQjN1f6Xq72ilcF+ 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: List-Subscribe: List-Unsubscribe: On Wed, Aug 14, 2024 at 3:00=E2=80=AFPM Shakeel Butt wrote: > > Memcg v1 provides soft limit functionality for the best effort memory > sharing between multiple workloads on a system. It is usually triggered > through kswapd and at the moment does not reclaim kernel memory. > > Memcg v2 provide more straightforward best effort (memory.low) and hard "provides" > protection (memory.min) functionalities. Let's initiate the deprecation > of soft limit from v1 and gather if v2 needs something more to move the > existing v1 users to v2 regarding soft limit. > > Signed-off-by: Shakeel Butt Reviewed-by: T.J. Mercier > --- > Changes since v1: > - N/A > > Documentation/admin-guide/cgroup-v1/memory.rst | 8 ++++++-- > mm/memcontrol-v1.c | 3 +++ > 2 files changed, 9 insertions(+), 2 deletions(-) > > diff --git a/Documentation/admin-guide/cgroup-v1/memory.rst b/Documentati= on/admin-guide/cgroup-v1/memory.rst > index 0114d758beab..6831c6c16e3f 100644 > --- a/Documentation/admin-guide/cgroup-v1/memory.rst > +++ b/Documentation/admin-guide/cgroup-v1/memory.rst > @@ -78,6 +78,8 @@ Brief summary of control files. > memory.memsw.max_usage_in_bytes show max memory+Swap usage recorded > memory.soft_limit_in_bytes set/show soft limit of memory usage > This knob is not available on CONFIG= _PREEMPT_RT systems. > + This knob is deprecated and shouldn= 't be > + used. > memory.stat show various statistics > memory.use_hierarchy set/show hierarchical account enable= d > This knob is deprecated and shouldn= 't be > @@ -701,8 +703,10 @@ For compatibility reasons writing 1 to memory.use_hi= erarchy will always pass:: > > # echo 1 > memory.use_hierarchy > > -7. Soft limits > -=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > +7. Soft limits (DEPRECATED) > +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D > + > +THIS IS DEPRECATED! > > Soft limits allow for greater sharing of memory. The idea behind soft li= mits > is to allow control groups to use as much of the memory as needed, provi= ded > diff --git a/mm/memcontrol-v1.c b/mm/memcontrol-v1.c > index b8e2ee454eaa..e0bb54e42011 100644 > --- a/mm/memcontrol-v1.c > +++ b/mm/memcontrol-v1.c > @@ -2458,6 +2458,9 @@ static ssize_t mem_cgroup_write(struct kernfs_open_= file *of, > if (IS_ENABLED(CONFIG_PREEMPT_RT)) { > ret =3D -EOPNOTSUPP; > } else { > + pr_warn_once("soft_limit_in_bytes is deprecated a= nd will be removed. " > + "Please report your usecase to linux= -mm@kvack.org if you " > + "depend on this functionality.\n"); > WRITE_ONCE(memcg->soft_limit, nr_pages); > ret =3D 0; > } > -- > 2.43.5 >