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 244EAC77B6D for ; Thu, 30 Mar 2023 07:39:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230317AbjC3Hjj (ORCPT ); Thu, 30 Mar 2023 03:39:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39936 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229732AbjC3Hjh (ORCPT ); Thu, 30 Mar 2023 03:39:37 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [195.135.220.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 808AB4213; Thu, 30 Mar 2023 00:39:36 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id 26AA121B00; Thu, 30 Mar 2023 07:39:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1680161975; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=g18B/GLg5ItJpD8zvJQQFzAO1axtsluF41GXm3XAUWQ=; b=ET0uIz8SFpap4Z0OGPb9kwXXtyHW/o/NGozAbd+0d3gbFzcP0A1LuFuJJJfq/l87AkaSbV PgKMOzdr17x6a4N6mNu8/3S0yq7fyz8szN2RSGvlRHH+6oHlgPx7hTfNDt5u9aESoovany 8D/iM3t2ToRiYsbtSkzNzWdUvaSrkg0= Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 06E591348E; Thu, 30 Mar 2023 07:39:34 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 5x/vOrY8JWRyfAAAMHmgww (envelope-from ); Thu, 30 Mar 2023 07:39:34 +0000 Date: Thu, 30 Mar 2023 09:39:34 +0200 From: Michal Hocko To: Yosry Ahmed Cc: Tejun Heo , Josef Bacik , Jens Axboe , Zefan Li , Johannes Weiner , Roman Gushchin , Shakeel Butt , Muchun Song , Andrew Morton , Michal =?iso-8859-1?Q?Koutn=FD?= , Vasily Averin , cgroups@vger.kernel.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, bpf@vger.kernel.org Subject: Re: [PATCH v2 7/9] workingset: memcg: sleep when flushing stats in workingset_refault() Message-ID: References: <20230328221644.803272-1-yosryahmed@google.com> <20230328221644.803272-8-yosryahmed@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230328221644.803272-8-yosryahmed@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue 28-03-23 22:16:42, Yosry Ahmed wrote: > In workingset_refault(), we call > mem_cgroup_flush_stats_atomic_ratelimited() to flush stats within an > RCU read section and with sleeping disallowed. Move the call above > the RCU read section and allow sleeping to avoid unnecessarily > performing a lot of work without sleeping. Could you say few words why the flushing is done before counters are updated rather than after (the RCU section)? -- Michal Hocko SUSE Labs