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 320CDC47422 for ; Fri, 26 Jan 2024 21:28:43 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BAEE16B0092; Fri, 26 Jan 2024 16:28:42 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B5ED86B0093; Fri, 26 Jan 2024 16:28:42 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A26226B0095; Fri, 26 Jan 2024 16:28:42 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 8FCC46B0092 for ; Fri, 26 Jan 2024 16:28:42 -0500 (EST) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 5947EC0D7F for ; Fri, 26 Jan 2024 21:28:42 +0000 (UTC) X-FDA: 81722751684.22.5BC0312 Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf30.hostedemail.com (Postfix) with ESMTP id CE30380017 for ; Fri, 26 Jan 2024 21:28:39 +0000 (UTC) Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=MXv0mHLg; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf30.hostedemail.com: domain of chrisl@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=chrisl@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1706304520; 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=gNqHsP0QzNPcNrc9Xlx0VNVIhnZmWNJT8PJvuvOCBDE=; b=wKFNYa2cOw8rRLPqhl9vWITIv+0/mfd+Sn1QNVnSe1wvcajVZxrNOCvVeq8doLqhOaLfBH UiX/qCDJgQkuMY4Krf7U/nXgdnA9GnRs1HiVbeanvKCn2qla/vWxByWLw8u8UinFI16fJ1 Jav0xHDw0xdqcU3W5Mwd2cL+O5EuaIk= ARC-Authentication-Results: i=1; imf30.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=MXv0mHLg; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf30.hostedemail.com: domain of chrisl@kernel.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=chrisl@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1706304520; a=rsa-sha256; cv=none; b=h5SsTkck52kL9P0DcgepXMvW2gdepr1eE0RPkbpewjKiQsIiRpekfvistVJAuLE7zQ73TB cSHxBwuqEDEj2QzmKCCB3V9bA4dh6Y/t/Z2MXeF4zvRyOxZko3uprAW1LJ2Yvnopl/xk0H VgiyKJFHFvNvQsW8401n0sd8u4HEMLw= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 934B8CE12B9 for ; Fri, 26 Jan 2024 21:28:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88CBEC433B1 for ; Fri, 26 Jan 2024 21:28:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1706304515; bh=YPfJESNx63f8gXc8lRLZ4SNiww8xBncvURRDWEv5tbo=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=MXv0mHLgFzPXzyJ+cXnF0NEHqEVMZis5J3xCyKd/vUQ+sNHMTeOvo5/UiRtp2prgn 3W/Ekzx29ky6ERqEG0FCD5c6Ax2AAJbBymQJM+C2XVk0rB5/CW42DI8ekyEPrBRgTJ Yqww8uOrdI/9wrwSyWcdaYFXqfOdoVOyWi5kA7B2gIpzbcjEiukdn/CrhmcXkxn0Bw 5xB52zJNgfDqQyfu23v4p6ZkQ9QhiLlxF5utjPu5p4kRaffbFWCjmyECdEyz0Iosfj ECliNn6S60owiB5Y3Dt7zuQUzi8wKpJ+RVoa08wc4iNDVH2z0tQOTXHHNP4ZS4f+TQ QNW4TQCmxSN7w== Received: by mail-il1-f177.google.com with SMTP id e9e14a558f8ab-362a24b13d7so1392315ab.2 for ; Fri, 26 Jan 2024 13:28:35 -0800 (PST) X-Gm-Message-State: AOJu0YyCGuM85zGaLy1V193EeLewGn25hzQ/C7SipnRgdsz5cVC5OCXT WQl7XM8va+ee7G3MjImoro5vU04dOge4dvkyl74Q4dVB0xNXsq6Td/HSa8FSrPbaJ7iUWdWzvMw zLExztAEju+vHsNVhIp8jMsBL/dEHIH1EXA6z X-Google-Smtp-Source: AGHT+IGNlb8VMURjwURcB5NRJcTClkW/oSCzBM4dOU+vxLvtNdJmhdWtiahxnT4JY+ITOetdOigrlYtfxWOip3LQdxU= X-Received: by 2002:a92:d388:0:b0:361:98e2:90b1 with SMTP id o8-20020a92d388000000b0036198e290b1mr437960ilo.20.1706304514841; Fri, 26 Jan 2024 13:28:34 -0800 (PST) MIME-Version: 1.0 References: <20240126211927.1171338-1-tjmercier@google.com> In-Reply-To: <20240126211927.1171338-1-tjmercier@google.com> From: Chris Li Date: Fri, 26 Jan 2024 13:28:23 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2] mm: memcg: Don't periodically flush stats when memcg is disabled To: "T.J. Mercier" Cc: Johannes Weiner , Michal Hocko , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton , android-mm@google.com, Minchan Kim , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: CE30380017 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: 3qrj8jjan6oi43qrsrzm7wqt8krdd7j6 X-HE-Tag: 1706304519-993613 X-HE-Meta: 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 aLaHuvmR uJKbvavu73RIFmMKfEX4oD7cdvKPZMurmnajrirgrPtEqHiGMXkDNi8q5B+lxHfOEWcODVRZCzyIOOWNsrfH5FF8He2cmTerXvV8htjfguq5B6eHBGyO9n0p7MWfBPTwu3GnT5VZoaLN458eYq5c06vQ+NBtWAsPriJXVQ/rJaKyneOI53Yrv/8t/mzk0a8vP8Oips6lGJMNTmdeRcLu+NBVtkA5cfNpixCasvLGpVqDfBnWA/YHHoCEUx9Yk8tt1wooeJYZfvsZf4WIqchtndYYFokO9bS4e2q+CD9OF21iuXQWqq0+R5VuUZ9aWEHxDbEEHa72LZkh+SluX9eDTD29H8RGjpfTRY23geRpeKPHDSz0= 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: Hi T.J. Acked-by: Chris Li Chris On Fri, Jan 26, 2024 at 1:19=E2=80=AFPM T.J. Mercier = wrote: > > The root memcg is onlined even when memcg is disabled. When it's onlined > a 2 second periodic stat flush is started, but no stat flushing is > required when memcg is disabled because there can be no child memcgs. > Most calls to flush memcg stats are avoided when memcg is disabled as a > result of the mem_cgroup_disabled check added in 7d7ef0a4686a > ("mm: memcg: restore subtree stats flushing"), but the periodic flushing > started in mem_cgroup_css_online is not. Skip it. > > Fixes: aa48e47e3906 ("memcg: infrastructure to flush memcg stats") > Reported-by: Minchan Kim > Signed-off-by: T.J. Mercier > Acked-by: Shakeel Butt > Acked-by: Johannes Weiner > --- > mm/memcontrol.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index e4c8735e7c85..bad8f9dfc9ab 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -5586,7 +5586,7 @@ static int mem_cgroup_css_online(struct cgroup_subs= ys_state *css) > if (alloc_shrinker_info(memcg)) > goto offline_kmem; > > - if (unlikely(mem_cgroup_is_root(memcg))) > + if (unlikely(mem_cgroup_is_root(memcg)) && !mem_cgroup_disabled()= ) > queue_delayed_work(system_unbound_wq, &stats_flush_dwork, > FLUSH_TIME); > lru_gen_online_memcg(memcg); > -- > 2.43.0.429.g432eaa2c6b-goog > >