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=-9.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 BF7B6C433DB for ; Thu, 21 Jan 2021 20:29:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 76A7823A56 for ; Thu, 21 Jan 2021 20:29:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727081AbhAUU3K (ORCPT ); Thu, 21 Jan 2021 15:29:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45106 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727102AbhAUU1V (ORCPT ); Thu, 21 Jan 2021 15:27:21 -0500 Received: from mail-lj1-x22e.google.com (mail-lj1-x22e.google.com [IPv6:2a00:1450:4864:20::22e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 675ABC0613D6; Thu, 21 Jan 2021 12:26:39 -0800 (PST) Received: by mail-lj1-x22e.google.com with SMTP id e7so3978299ljg.10; Thu, 21 Jan 2021 12:26:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=CK9v4fJZez9oq+66O9lv/sWkyc4mUCFz9PdtPkQoRmA=; b=iFMSbE7wyUyKwmY2E7RnbbmjaygiXMHTQQ60cn4WAfXxZ8g0S0fer14cKskE48ekxP VdTpmX6UWmnlXXqAcib4ycO4wahuzrG9NoO0GuriWV2m/NSObN0GP3NNwxT1OWwIAjH7 Xv/hdEbRHiZRNicELlf5XS6XIOnoBITZt9QSQ5GoSjR2T708N6Gb6/3UfzfjKbDOi/NK SPdmED8emmi2l5EEXEJTKP5e1E7U6ZfjH2P69UHseqkzRoXByI7Ej6KoylCe6OfPXB0s jdV9fNRfzcjQyQi8ng1p4Ly99KDjHumsWxXDdsW15nyMEuJ3qrx56TB5fd8SZxAGhQCk yWRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=CK9v4fJZez9oq+66O9lv/sWkyc4mUCFz9PdtPkQoRmA=; b=FzeH4U0PjG6Zi6uu+GISkrMm6OzMZBOJSfFYvSNBL3i/7UNx8JeB4NFUnLOZGMSclL EAsGF7LErseBbkEPsbzm/XzHW0lOpBffULPwsh7ldNIOM9qVXJmkAN4YokTwAwMqm+16 bJzGY4tqfG1UAmTb0GyAU97BVes1UxTA0OaNYY0n94rqlZ5gWkVjSdJ2FxR1Pyrp73KM CRG/E1S4zy03aAXw2+rIopvUTOlHA6jxLfcYvmaNbH5FnRUgaF35atlFVopPEM7R/suX aPnFBDe5zPBI83zoB4e2f+/f0DdvFcV1lew7TFoBUs50+oE5iRuDgfAMl5Fei+qI2u1x zktA== X-Gm-Message-State: AOAM532h1boLg76aWcTOXxLlsFUrVhUVKUjPXzzLtLIRXfLZf669PCZm IsWed9qrTrSlujc+SFVsm28= X-Google-Smtp-Source: ABdhPJxqMS/xwXTHH3tlcom34rpxkP3S4uIPtEX0oIY58eN8T8BaeYIQel2RiI8MzWIM1Ib2ob0HPA== X-Received: by 2002:a2e:585:: with SMTP id 127mr522636ljf.131.1611260797957; Thu, 21 Jan 2021 12:26:37 -0800 (PST) Received: from pc638.lan (h5ef52e3d.seluork.dyn.perspektivbredband.net. [94.245.46.61]) by smtp.gmail.com with ESMTPSA id b3sm646370lff.190.2021.01.21.12.26.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Jan 2021 12:26:37 -0800 (PST) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Thu, 21 Jan 2021 21:26:35 +0100 To: qiang.zhang@windriver.com Cc: "Paul E. McKenney" , rcu@vger.kernel.org, linux-kernel@vger.kernel.org, urezki@gmail.com Subject: Re: [PATCH] rcu: Release per-cpu krcp page cache when CPU going offline Message-ID: <20210121202635.GB2454@pc638.lan> References: <20210121064949.16164-1-qiang.zhang@windriver.com> <20210121185615.GR2743@paulmck-ThinkPad-P72> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210121185615.GR2743@paulmck-ThinkPad-P72> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Qiang, > On Thu, Jan 21, 2021 at 02:49:49PM +0800, qiang.zhang@windriver.com wrote: > > From: Zqiang > > > > If CPUs go offline, the corresponding krcp's page cache can > > not be use util the CPU come back online, or maybe the CPU > > will never go online again, this commit therefore free krcp's > > page cache when CPUs go offline. > > > > Signed-off-by: Zqiang > Do you consider it as an issue? We have 5 pages per CPU, that is 20480 bytes. -- Vlad Rezki