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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E823FC433EF for ; Tue, 10 May 2022 22:24:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235916AbiEJWYL (ORCPT ); Tue, 10 May 2022 18:24:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59958 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235671AbiEJWYG (ORCPT ); Tue, 10 May 2022 18:24:06 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 697A628ED34 for ; Tue, 10 May 2022 15:24:05 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0077A61800 for ; Tue, 10 May 2022 22:24:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4F56CC385CF; Tue, 10 May 2022 22:24:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1652221444; bh=0WjUZ8SWsDvldaTg1LNmvpZ3Z39RWfo1B5J3rr9Oni4=; h=Date:To:From:Subject:From; b=jRINyUJqsdhtiDSQXR2WEEe1mVd6ysI0rkc1dMb6L7bRy5L6dzucR0P2Jp3zKVH8u 4AXW/KXm3c3YDCMCasRhQB3u+cj+3NOQkXsEhlzbu3B2bqey2isVJ3dhjSyUbbGo3D ikEAEs7aKG3s+kju2RLA9+kdpXFkAinjT56Cjf9Q= Date: Tue, 10 May 2022 15:24:03 -0700 To: mm-commits@vger.kernel.org, shakeelb@google.com, roman.gushchin@linux.dev, mhocko@suse.com, hannes@cmpxchg.org, rganesan@arista.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-memcontrol-export-memcg-watermark-via-sysfs-for-v2-memcg.patch added to mm-unstable branch Message-Id: <20220510222404.4F56CC385CF@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/memcontrol: export memcg->watermark via sysfs for v2 memcg has been added to the -mm mm-unstable branch. Its filename is mm-memcontrol-export-memcg-watermark-via-sysfs-for-v2-memcg.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memcontrol-export-memcg-watermark-via-sysfs-for-v2-memcg.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Ganesan Rajagopal Subject: mm/memcontrol: export memcg->watermark via sysfs for v2 memcg We run a lot of automated tests when building our software and run into OOM scenarios when the tests run unbounded. v1 memcg exports memcg->watermark as "memory.max_usage_in_bytes" in sysfs. We use this metric to heuristically limit the number of tests that can run in parallel based on per test historical data. This metric is currently not exported for v2 memcg and there is no other easy way of getting this information. getrusage() syscall returns "ru_maxrss" which can be used as an approximation but that's the max RSS of a single child process across all children instead of the aggregated max for all child processes. The only work around is to periodically poll "memory.current" but that's not practical for short-lived one-off cgroups. Hence, expose memcg->watermark as "memory.peak" for v2 memcg. Link: https://lkml.kernel.org/r/20220507050916.GA13577@us192.sjc.aristanetworks.com Signed-off-by: Ganesan Rajagopal Acked-by: Shakeel Butt Acked-by: Johannes Weiner Cc: Michal Hocko Cc: Roman Gushchin Signed-off-by: Andrew Morton --- Documentation/admin-guide/cgroup-v2.rst | 7 +++++++ mm/memcontrol.c | 13 +++++++++++++ 2 files changed, 20 insertions(+) --- a/Documentation/admin-guide/cgroup-v2.rst~mm-memcontrol-export-memcg-watermark-via-sysfs-for-v2-memcg +++ a/Documentation/admin-guide/cgroup-v2.rst @@ -1229,6 +1229,13 @@ PAGE_SIZE multiple when read back. the target cgroup. If less bytes are reclaimed than the specified amount, -EAGAIN is returned. + memory.peak + A read-only single value file which exists on non-root + cgroups. + + The max memory usage recorded for the cgroup and its + descendants since the creation of the cgroup. + memory.oom.group A read-write single value file which exists on non-root cgroups. The default value is "0". --- a/mm/memcontrol.c~mm-memcontrol-export-memcg-watermark-via-sysfs-for-v2-memcg +++ a/mm/memcontrol.c @@ -6146,6 +6146,14 @@ static u64 memory_current_read(struct cg return (u64)page_counter_read(&memcg->memory) * PAGE_SIZE; } +static u64 memory_peak_read(struct cgroup_subsys_state *css, + struct cftype *cft) +{ + struct mem_cgroup *memcg = mem_cgroup_from_css(css); + + return (u64)memcg->memory.watermark * PAGE_SIZE; +} + static int memory_min_show(struct seq_file *m, void *v) { return seq_puts_memcg_tunable(m, @@ -6450,6 +6458,11 @@ static struct cftype memory_files[] = { .read_u64 = memory_current_read, }, { + .name = "peak", + .flags = CFTYPE_NOT_ON_ROOT, + .read_u64 = memory_peak_read, + }, + { .name = "min", .flags = CFTYPE_NOT_ON_ROOT, .seq_show = memory_min_show, _ Patches currently in -mm which might be from rganesan@arista.com are mm-memcontrol-export-memcg-watermark-via-sysfs-for-v2-memcg.patch