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 0366DC3F6B0 for ; Mon, 15 Aug 2022 22:38:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348855AbiHOWiU (ORCPT ); Mon, 15 Aug 2022 18:38:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38556 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1350817AbiHOWhL (ORCPT ); Mon, 15 Aug 2022 18:37:11 -0400 Received: from mail-pl1-x634.google.com (mail-pl1-x634.google.com [IPv6:2607:f8b0:4864:20::634]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ED5681306AC; Mon, 15 Aug 2022 12:50:33 -0700 (PDT) Received: by mail-pl1-x634.google.com with SMTP id p18so7235408plr.8; Mon, 15 Aug 2022 12:50:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:from:to:cc; bh=Di1CBe/l3lFU1XEMEHMD/NMLKrrpGfsfoqHbgdL41rY=; b=JuMvrFxcpiKSsluaG1sm5UeOdp2pC3giGOS2OG59Y//fuQbFRfELDeH/pCcBIswiDf lZAf9nK/Y2R/Slxxx4YUgrO+F12ef80ywTcQLYTu8qeuofUcBPT7wsZnHVA+pr4+0/Cj 2tUC4IQVIStZaEDFenvFjtb8mmfyzTXMYIyz/i28Sb2IcML8EkxfwWRAP/3mhdWUdJG5 VVHotdeDOBc2ap2gYTcc16AbrAOrCJwUGwpW0kqck33YQQZ/msYuYMqPoV3dfpYUAbdG l7XZwTBXqp8itTZ6ESNEpnA/05+OnSneaC/vjjcsmmudVYim9hPHM6KvxdLxnmzlWVOM Qjxw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:sender:x-gm-message-state:from:to:cc; bh=Di1CBe/l3lFU1XEMEHMD/NMLKrrpGfsfoqHbgdL41rY=; b=1SfrJUrADimY6sR5KcE/VuHa6d+C7K3gPr+r+TpiByTeV268iEsn0bk/q4/Mh8YhD1 jBEE0+ZaRwhZotL9vEDR+W9F+m+zf6sjhkgjeqZG1ROb3pJZ62lcrDXtO3rLGv97vD8k K2uT8RsIM5MDkf3dRf9Q1k7lTi66xYb8zPzt38tOVyChsDcQsghw8LBpAjFz7fVlonWj Hdg4AaQAWQTjWKSlSIg/7CUTDY689NnodX0fZijDipTEWSiy2oNV0Dq3AkP8ubNoSJl1 b9JM0i8XVSDLBVOu6MH6bVGFQHzGc5hs0xdBDy8l5n8xBU4aP8q+6doLa76nrRl2gMDA zlvg== X-Gm-Message-State: ACgBeo3twqA0ZIOefX3L9duv83XT54z8qr2i0Gm31Cj52JXAK2smUQ6X 0dzwEkGp7D2UYAe101pxxaE= X-Google-Smtp-Source: AA6agR4R1QdI6pW/aafCRuGM/0QFfLfWgDKOb+nYbwM1XcyQTAJaJsWfdgHpO+kUWsnlfWUBKtOq6A== X-Received: by 2002:a17:902:8f8a:b0:170:8df4:eebd with SMTP id z10-20020a1709028f8a00b001708df4eebdmr18681986plo.116.1660593032457; Mon, 15 Aug 2022 12:50:32 -0700 (PDT) Received: from localhost ([2620:10d:c090:400::5:3a69]) by smtp.gmail.com with ESMTPSA id b14-20020a170902650e00b0016c06a10861sm7351319plk.74.2022.08.15.12.50.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Aug 2022 12:50:31 -0700 (PDT) Sender: Tejun Heo Date: Mon, 15 Aug 2022 09:50:30 -1000 From: Tejun Heo To: Johannes Weiner Cc: Chengming Zhou , corbet@lwn.net, surenb@google.com, mingo@redhat.com, peterz@infradead.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, songmuchun@bytedance.com Subject: Re: [PATCH v2 09/10] sched/psi: per-cgroup PSI stats disable/re-enable interface Message-ID: References: <20220808110341.15799-1-zhouchengming@bytedance.com> <20220808110341.15799-10-zhouchengming@bytedance.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Hello, On Mon, Aug 15, 2022 at 11:49:55AM -0400, Johannes Weiner wrote: > I think it should also add/remove the pressure files when enabling and > disabling the aggregation, since their contents would be stale and > misleading. > > Take a look at cgroup_add_dfl_cftypes() and cgroup_rm_cftypes() The problem with adding cftypes dynamically is that it can fail, which isn't the end of the world here but still kinda sucks. I think what we actually wanna do is hiding and unhiding while keeping all the data structures in place which is needed somewhere else anyway. Thanks. -- tejun