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 EE048C77B61 for ; Tue, 28 Mar 2023 13:26:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231819AbjC1N02 (ORCPT ); Tue, 28 Mar 2023 09:26:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46634 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229848AbjC1N01 (ORCPT ); Tue, 28 Mar 2023 09:26:27 -0400 Received: from mail-yb1-xb2b.google.com (mail-yb1-xb2b.google.com [IPv6:2607:f8b0:4864:20::b2b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 188A57293 for ; Tue, 28 Mar 2023 06:26:26 -0700 (PDT) Received: by mail-yb1-xb2b.google.com with SMTP id i6so15014943ybu.8 for ; Tue, 28 Mar 2023 06:26:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; t=1680009985; 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=8bJymL0yBKvMYTD1Xc/qu3GglkLI9FvB8Lv/yuqvRQc=; b=eZy1jM+Kd53ZIzWNbOqgWbWL45Dr+Nw9ANo2PWtQbmVaWtrjCdrDAwPWv3yK9p7pwn NdX2H4aYwg5QRk1CBz5Q+PDjxvTvxqOymyHBX8fhYiwV1krbMVJo3/thEa0eeD2ncqtr 11MW+NX2xIo4RJWivNGz5B/TSrAzZmnzZLla0MAE4rR5mfGrSLcqNM08TimNues3s+u/ 7Y5UuSgD0RzJHWmkNAiahoW2q/TpdkuXvww90IJ4ZT0HDPDLUtzwosiL6k1Ay9MagttR Xll6pq0j7ma1HAlACEp1cDHFcxilfs9tVtLUSpSaT3tswN2NAz96yvtBv6Q2jzszETWW 11rA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680009985; 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=8bJymL0yBKvMYTD1Xc/qu3GglkLI9FvB8Lv/yuqvRQc=; b=EyYjBxE9yB/rBF/F0QAiDKZgLPoNEFP/yFVwI/IzEJVHf+LwYiSsSliDNAYJ4/I5Iy e9wI3ThqpBVpNUeGPqboHLN+P7B7XDJI/uu3LsZFCNyokTCdGh+LgvU/RyPxWOyOH0nJ W0DkMauSny2zfaX/7QkvMwJm/b/QeSvAI7PfXaLh490Cmps2Z8VvJxda59a9SP+1gbZO dT6W2FAKZNkm49br6b/xV0uwl8EttrSzgfeCLm5dlMKzQ1o74vGLmkm6cEDQcWiMWAZq llUEMmoIrtVRO4TE3FhWc6YIiBE5rajR95T1yxwxKLqQMmdDmeTUjNoTiR+w5uTLqc7K afOQ== X-Gm-Message-State: AAQBX9fydzn7mPDdVFmoPbC4P1gB61QsOaQp3rbaYhTPKmcqKVVbqojN +NzD6Cn4l9dnnVramwM/Vreffsi+D3ofEvcjxqBPSA== X-Google-Smtp-Source: AKy350Zja1hP9WxwT3nbR4kgm/32+esIcZm0ttA35DlxybRpCP5Bjc/9FU70PICjQ5T/32D5BoknkSe4x+2lmAwB5IY= X-Received: by 2002:a25:e054:0:b0:b6b:d3f3:45af with SMTP id x81-20020a25e054000000b00b6bd3f345afmr9852686ybg.1.1680009985214; Tue, 28 Mar 2023 06:26:25 -0700 (PDT) MIME-Version: 1.0 References: <20230328061638.203420-1-yosryahmed@google.com> <20230328061638.203420-4-yosryahmed@google.com> In-Reply-To: <20230328061638.203420-4-yosryahmed@google.com> From: Shakeel Butt Date: Tue, 28 Mar 2023 06:26:14 -0700 Message-ID: Subject: Re: [PATCH v1 3/9] memcg: do not flush stats in irq context To: Yosry Ahmed Cc: Tejun Heo , Josef Bacik , Jens Axboe , Zefan Li , Johannes Weiner , Michal Hocko , Roman Gushchin , Muchun Song , Andrew Morton , =?UTF-8?Q?Michal_Koutn=C3=BD?= , Vasily Averin , cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Mon, Mar 27, 2023 at 11:16=E2=80=AFPM Yosry Ahmed wrote: > > Currently, the only context in which we can invoke an rstat flush from > irq context is through mem_cgroup_usage() on the root memcg when called > from memcg_check_events(). An rstat flush is an expensive operation that > should not be done in irq context, so do not flush stats and use the > stale stats in this case. > > Arguably, usage threshold events are not reliable on the root memcg > anyway since its usage is ill-defined. > > Suggested-by: Johannes Weiner > Suggested-by: Shakeel Butt > Signed-off-by: Yosry Ahmed Acked-by: Shakeel Butt