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 X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3BD2C433C1 for ; Wed, 24 Mar 2021 04:12:21 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 11F80619B2 for ; Wed, 24 Mar 2021 04:12:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 11F80619B2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=bytedance.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 808ED6B0298; Wed, 24 Mar 2021 00:12:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 792286B029A; Wed, 24 Mar 2021 00:12:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 60BF76B029C; Wed, 24 Mar 2021 00:12:19 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0231.hostedemail.com [216.40.44.231]) by kanga.kvack.org (Postfix) with ESMTP id 3FC266B0298 for ; Wed, 24 Mar 2021 00:12:19 -0400 (EDT) Received: from smtpin20.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id DAF4B181AF5C4 for ; Wed, 24 Mar 2021 04:12:18 +0000 (UTC) X-FDA: 77953445556.20.183FD25 Received: from mail-pg1-f179.google.com (mail-pg1-f179.google.com [209.85.215.179]) by imf14.hostedemail.com (Postfix) with ESMTP id 894B4C0001FA for ; Wed, 24 Mar 2021 04:12:12 +0000 (UTC) Received: by mail-pg1-f179.google.com with SMTP id l76so1680989pga.6 for ; Tue, 23 Mar 2021 21:12:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=p25/A4gvraG4GrSK0QNzOG7a5VxfROedfZ595WlOtfc=; b=dcybOyPrXjytyX5pqMpHq8KRfUwYSfHAcYJklNkF9C0WqV2l8aCcMxYGdOP4D7qhdp copt+iCQiFQ4KuUx9E+HAFPPUgnrXOPsETJnboSF5n22AHxlpHcp2Agbpes9Zkz2UAOD qC1Y2WXXcu5ITAMwqykA1uqqWA9fAChSeddHX4PwUcNjUIHpIzkrL5rfQfZQqhPBpfxb kVtqT35+slxDS0ArWP5GlCCCFg4+rUw+Qy3RJQZ/2pUqDDgZLYu7PdJ1BWFKg9JvT9ac YYlghi1IuADLX0m0e2vfIKIjOk445huOG8NAWzL/MTCPoDrTCtJ75wyCOvP8wfeN3zHt Gt9A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=p25/A4gvraG4GrSK0QNzOG7a5VxfROedfZ595WlOtfc=; b=fSeCCKGT68qHO4QBINdNINmfhA+i7CBqgP4cT93TQ29GT5ixjgvd7Z9S8kBq7mm+Hq pimhX7o6s8bO0pBaA1Qt0QKUa85idYFZNlg31grs4G+fvp/0K/YtAgxjQDeDqpJ9+KrK Ecz0UaWzGs3JdhT3zZoCmhPMnKUa9zzO4Ce2zeQauc5qesSiJgo8sXvVfIADyjj5f3bj Z49pUm6KJL/Z1ldKcDU1u/qsIfET0xh/3waO+baHzpwst/Z6A5gy/aH2ysNR8Q+Q7Ktz rD+AP4X3OsvoD6rC2ALMS1Yvys6vbgvj0iCcGJZXrxdY6wWZGVuO4plSiNbFNY2V+j20 8zzA== X-Gm-Message-State: AOAM533GgIpM55pb4rMZLxX8BJ/iQcPH9/grpvcYX3OA8Wlf3nckKy70 RKIdnt3bOslx0xWlA0YE5HeaxOIQc4MTe9C1Z81Vhg== X-Google-Smtp-Source: ABdhPJzhnlivy0sipBYYKv2VrxoVNvIAAAZInhgxCH+QDjHCo855VaazR7l4bm1Vgd+lSac03FJFIeqwomdjoNGFR80= X-Received: by 2002:a65:6645:: with SMTP id z5mr1312058pgv.273.1616559133180; Tue, 23 Mar 2021 21:12:13 -0700 (PDT) MIME-Version: 1.0 References: <20210323145653.25684-1-songmuchun@bytedance.com> In-Reply-To: <20210323145653.25684-1-songmuchun@bytedance.com> From: Muchun Song Date: Wed, 24 Mar 2021 12:11:35 +0800 Message-ID: Subject: Re: [PATCH] mm: memcontrol: fix memsw uncharge for root_mem_cgroup To: Roman Gushchin , Johannes Weiner , Michal Hocko , Andrew Morton , Shakeel Butt , Vladimir Davydov Cc: LKML , Linux Memory Management List Content-Type: text/plain; charset="UTF-8" X-Stat-Signature: ujufrdnyrkie9j7kkexh465fdt5xjq4h X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 894B4C0001FA Received-SPF: none (bytedance.com>: No applicable sender policy available) receiver=imf14; identity=mailfrom; envelope-from=""; helo=mail-pg1-f179.google.com; client-ip=209.85.215.179 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1616559132-398761 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, Mar 23, 2021 at 11:04 PM Muchun Song wrote: > > The pages aren't accounted at the root level, so we cannot uncharge the > page to the memsw counter for the root memcg. Fix this. > > Fixes: 1f47b61fb407 ("mm: memcontrol: fix swap counter leak on swapout from offline cgroup") > Signed-off-by: Muchun Song I am very sorry. I should repent. I suddenly realise the fix is totally wrong. Because the @memcg cannot be root memcg when @memcg != @swap_memcg. Please ignore this patch. I am very sorry for the noise. And sorry to Michal. > --- > mm/memcontrol.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 533b4b31b464..7d765a106684 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -7155,7 +7155,8 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry) > if (!cgroup_memory_noswap && memcg != swap_memcg) { > if (!mem_cgroup_is_root(swap_memcg)) > page_counter_charge(&swap_memcg->memsw, nr_entries); > - page_counter_uncharge(&memcg->memsw, nr_entries); > + if (!mem_cgroup_is_root(memcg)) > + page_counter_uncharge(&memcg->memsw, nr_entries); > } > > /* > -- > 2.11.0 >