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 AD7FBC369AB for ; Fri, 11 Apr 2025 21:13:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 53E6E680026; Fri, 11 Apr 2025 17:13:08 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 4EECF680024; Fri, 11 Apr 2025 17:13:08 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 38E0F680026; Fri, 11 Apr 2025 17:13:08 -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 1BD3B680024 for ; Fri, 11 Apr 2025 17:13:08 -0400 (EDT) Received: from smtpin23.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 2ED88BA1CD for ; Fri, 11 Apr 2025 21:13:09 +0000 (UTC) X-FDA: 83323013298.23.FAF395A Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf07.hostedemail.com (Postfix) with ESMTP id DD8CF40003 for ; Fri, 11 Apr 2025 21:13:06 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=eH0ggCyk; dmarc=pass (policy=quarantine) header.from=redhat.com; spf=pass (imf07.hostedemail.com: domain of llong@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=llong@redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1744405986; 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=J2KJ3vbhhei7UlaB6YBbaCcfWrpCjfMnuhrykVfj6hA=; b=2WIfehcaMJsF2b+w1Ll4m9nitQYHGqZFFOgYgLjWb3JdMbqlQ43vhVxwulh4ZpLlAb0nfT lZvT0CvksUKpiIDhSmq+xaU1bc8nu8r6rbaOrBmE1rJoNucw0fDrqKsP+yS7dDOICDMrWq jUF5c3kBkmVAnHP2UQeTpTFp/iXhDEs= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=eH0ggCyk; dmarc=pass (policy=quarantine) header.from=redhat.com; spf=pass (imf07.hostedemail.com: domain of llong@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=llong@redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1744405986; a=rsa-sha256; cv=none; b=IpeudBNM/vl1esglPHaI8wcGOKaPMAbnCKNMXIAWqJuEbhoPw5r4WUl3VK9ZpZ81Er0CRI 27kpnz8pZODHosQhYbIzSPFPWDROHq2Npd2jUTLKoc+jP0nspd8mJJ7UDSg8UZtfmatyoL zxDUIl3iiti4Aa4d54MLSu1aDJxKuLA= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744405986; h=from:from: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; bh=J2KJ3vbhhei7UlaB6YBbaCcfWrpCjfMnuhrykVfj6hA=; b=eH0ggCyk22DcE50VOp67yt5mDwBy/CaIThzf4ECYWtqWlRDDS2MJixXgxSx0T6JgqtMNwN GH5/cjqBh2fYAlCc+v15GkvY4W9gMXIcyJCfdFSwrha7nxCEzGVB60KxJpF55SIYrcddi9 AzFBn0E7tt4fLLl4BFIc3nXTjCRRx4Q= Received: from mail-qk1-f200.google.com (mail-qk1-f200.google.com [209.85.222.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-684-TmZ7E2iFMXqRcynZyMsk0Q-1; Fri, 11 Apr 2025 17:13:03 -0400 X-MC-Unique: TmZ7E2iFMXqRcynZyMsk0Q-1 X-Mimecast-MFC-AGG-ID: TmZ7E2iFMXqRcynZyMsk0Q_1744405982 Received: by mail-qk1-f200.google.com with SMTP id af79cd13be357-7c3c5e92d41so379676885a.1 for ; Fri, 11 Apr 2025 14:13:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1744405982; x=1745010782; h=content-transfer-encoding:in-reply-to:content-language:references :cc:to:subject:user-agent:mime-version:date:message-id:from :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=J2KJ3vbhhei7UlaB6YBbaCcfWrpCjfMnuhrykVfj6hA=; b=FSNaPPUF2iKqWWjbrisU5suq6erzCgtHvAJMvHRQEnzRHnBype71481xliiX2jPpq4 iJWTKy0/YHKcrqAxPjsYRBt2p08pkFPOGNrxmtTTQrUpd+NYZFfrdarHKcjNYXy2lf0e wxlnAXNQg4OxZRerpiBA06288JrxIPbqrJEMpECBT0FxgF2wR2LHgVFIjReJKwaTGbqY yeu2ChhLCKkrbvk2H8lYyuc4aX0rXkPB5RuHUrFzbbYnrZfCWeyctfWhj4W+iea8InLC vQc10XMLSLxX8LDt38suU+b42J/E1vO7oNmW9SV/t5X2IdNtxk2mKtMJrurF/GCoqvv9 risg== X-Forwarded-Encrypted: i=1; AJvYcCXbNG7Ncm3f5SpM3Ylaa7qLibKC3Hyp1OeN3A55NSQy850UhmTHc+XWS8clfjzf/YumjDYvcp5png==@kvack.org X-Gm-Message-State: AOJu0YyETLOMRJ6Ih9lAdvRYT4NHXhvC4pCAOOGL/K8g+71ZGa+0FCeC lDtzfiKEjqR/zM5QF8UYOLz+XoOtsw8xxEej3mhEm2bFHacunDqT8fOHYdWT/aSaruIo6LpB0gX an12TBPsi7vfkehm/4eb2/Xq5vhfkJZy5CyZQTZ7IZitQzTjf X-Gm-Gg: ASbGncvH5kSViDvNBYQqfwX9Q3ncFHvWfjFfVTYV2xj95J2wVSZsQzcnEjOJr0mM3B2 xiFgn23zwSgNlW42VchzSTiMA2L5vd7nBhUAMdoaHgRYOBeNQvbqmrNvgQ1PlcJPlk3CzUWm40K x4Dy8whhikU7cRGVW9eQ1lTj4WRCMp8i2RcvTnSIUvzaVY9U6weRQLXHVcuuHb9x5Gy74AxoL9k CdKfnCsc+2sfxfixPMGFtbKMq24680C3LGUzphEmH5qFqVjRDvV1HJzpOfwIYZgptPgRRkGhylg CeTD1qW/hvZ4fuPgWXlevUnMThn92Z4Sc7ueAlA3JrYdjG1VnqgcxijtGw== X-Received: by 2002:a05:620a:bce:b0:7c5:6ba5:dd65 with SMTP id af79cd13be357-7c7af20dfccmr702416885a.55.1744405982624; Fri, 11 Apr 2025 14:13:02 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEleT+JnQIZjjY1BnHjF+zn74YxSy7C0p+IDn0drbShDJE5Rd9yuVCeBx0//zZEmHI9Zxuqfw== X-Received: by 2002:a05:620a:bce:b0:7c5:6ba5:dd65 with SMTP id af79cd13be357-7c7af20dfccmr702413785a.55.1744405982228; Fri, 11 Apr 2025 14:13:02 -0700 (PDT) Received: from ?IPV6:2601:188:c100:5710:315f:57b3:b997:5fca? ([2601:188:c100:5710:315f:57b3:b997:5fca]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7c7a89f9639sm313660585a.78.2025.04.11.14.13.00 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 11 Apr 2025 14:13:01 -0700 (PDT) From: Waiman Long X-Google-Original-From: Waiman Long Message-ID: <0158e459-c205-4a88-9711-3dea2bca71ae@redhat.com> Date: Fri, 11 Apr 2025 17:13:00 -0400 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 1/2] mm/vmscan: Skip memcg with !usage in shrink_node_memcgs() To: =?UTF-8?Q?Michal_Koutn=C3=BD?= Cc: Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton , Tejun Heo , Shuah Khan , linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org References: <20250407162316.1434714-1-longman@redhat.com> <20250407162316.1434714-2-longman@redhat.com> In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 4OQob0LZURw9eE9gpqD1w_wE05c_gvW8jv3SkyVRuFo_1744405982 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: DD8CF40003 X-Stat-Signature: y6q5s9cd961naxzycsxa8go3bz61hqpe X-Rspam-User: X-HE-Tag: 1744405986-168223 X-HE-Meta: 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 8073BE4h 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 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 4/11/25 1:11 PM, Michal Koutný wrote: > Hello. > > On Mon, Apr 07, 2025 at 12:23:15PM -0400, Waiman Long wrote: >> --- a/mm/memcontrol-v1.h >> +++ b/mm/memcontrol-v1.h >> @@ -22,8 +22,6 @@ >> iter != NULL; \ >> iter = mem_cgroup_iter(NULL, iter, NULL)) >> >> -unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap); >> - > Hm, maybe keep it for v1 only where mem_cgroup_usage has meaning for > memsw (i.e. do the opposite and move the function definition to -v1.c). memcontrol-v1.c also include mm/internal.h. That is the reason why I can remove it from here. >> void drain_all_stock(struct mem_cgroup *root_memcg); >> >> unsigned long memcg_events(struct mem_cgroup *memcg, int event); >> diff --git a/mm/vmscan.c b/mm/vmscan.c >> index b620d74b0f66..a771a0145a12 100644 >> --- a/mm/vmscan.c >> +++ b/mm/vmscan.c >> @@ -5963,6 +5963,10 @@ static void shrink_node_memcgs(pg_data_t *pgdat, struct scan_control *sc) >> >> mem_cgroup_calculate_protection(target_memcg, memcg); >> >> + /* Skip memcg with no usage */ >> + if (!mem_cgroup_usage(memcg, false)) >> + continue; >> + > (Not only for v2), there is mem_cgroup_size() for this purpose (already > used in mm/vmscan.c). My understanding is that mem_cgroup_usage() is for both v1 and v2, while mem_cgroup_size() is for v2 only. > >> if (mem_cgroup_below_min(target_memcg, memcg)) { >> /* >> * Hard protection. >> diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c >> index 16f5d74ae762..bab826b6b7b0 100644 >> --- a/tools/testing/selftests/cgroup/test_memcontrol.c >> +++ b/tools/testing/selftests/cgroup/test_memcontrol.c >> @@ -525,8 +525,13 @@ static int test_memcg_protection(const char *root, bool min) >> goto cleanup; >> } >> >> + /* >> + * Child 2 has memory.low=0, but some low protection is still being >> + * distributed down from its parent with memory.low=50M. So the low >> + * event count will be non-zero. >> + */ >> for (i = 0; i < ARRAY_SIZE(children); i++) { >> - int no_low_events_index = 1; >> + int no_low_events_index = 2; > See suggestion in > https://lore.kernel.org/lkml/awgbdn6gwnj4kfaezsorvopgsdyoty3yahdeanqvoxstz2w2ke@xc3sv43elkz5/ I have just replied on your suggestion. Cheers, Longman > > HTH, > Michal