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 C6DD7C3DA7A for ; Fri, 6 Jan 2023 15:02:17 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 261C38E0002; Fri, 6 Jan 2023 10:02:17 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 1EC608E0001; Fri, 6 Jan 2023 10:02:17 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 08C698E0002; Fri, 6 Jan 2023 10:02:17 -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 EEC9F8E0001 for ; Fri, 6 Jan 2023 10:02:16 -0500 (EST) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id B350D14095F for ; Fri, 6 Jan 2023 15:02:16 +0000 (UTC) X-FDA: 80324689872.17.CA655D2 Received: from r3-22.sinamail.sina.com.cn (r3-22.sinamail.sina.com.cn [202.108.3.22]) by imf14.hostedemail.com (Postfix) with ESMTP id 414CD10002A for ; Fri, 6 Jan 2023 15:02:09 +0000 (UTC) Authentication-Results: imf14.hostedemail.com; dkim=none; spf=pass (imf14.hostedemail.com: domain of hdanton@sina.com designates 202.108.3.22 as permitted sender) smtp.mailfrom=hdanton@sina.com; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1673017332; a=rsa-sha256; cv=none; b=ohknakwCphXNAVJd4KPwFvqgcM71tMsRTWoIM6hNVfwagWjgOq0wf3vpue2+tHEYiRmius xeiw2tClDvb/esJieaWqvBH6LVk4xHeVfovdN3LyjvgLkcbBmG11iEvFgnj5zptw4ez2XW xurbIBnYD22J+2UVzN38HHnysxRF7Tc= ARC-Authentication-Results: i=1; imf14.hostedemail.com; dkim=none; spf=pass (imf14.hostedemail.com: domain of hdanton@sina.com designates 202.108.3.22 as permitted sender) smtp.mailfrom=hdanton@sina.com; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1673017332; 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-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Wj+kQJPjKcUEBtvK9lISzPCdIuDPCLRUrUMb/21zikE=; b=iffmtfUGP0D/KREaJk9HWjauXZ46Y1B0VtP7f7cBDrxoBiDHn0KZOydm7TfifS4vdWDtDA NHRUl7BKt3f813XCOMFkS4L/bel5ofo5JgvDLaTNgMe6VSBa4GJz8Xj1WHH0DvDgyEky2c SNx7DFDUou60XoUZdIHbW+fi+ibZyS8= Received: from unknown (HELO localhost.localdomain)([114.249.57.238]) by sina.com (172.16.97.32) with ESMTP id 63B83716000193E1; Fri, 6 Jan 2023 22:58:32 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com X-SMAIL-MID: 303465628992 From: Hillf Danton To: Marcelo Tosatti Cc: atomlin@atomlin.com, frederic@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH v13 3/6] mm/vmstat: manage per-CPU stats from CPU context when NOHZ full Date: Fri, 6 Jan 2023 23:01:54 +0800 Message-Id: <20230106150154.4560-1-hdanton@sina.com> In-Reply-To: References: <20230105125218.031928326@redhat.com> <20230106001244.4463-1-hdanton@sina.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Queue-Id: 414CD10002A X-Rspamd-Server: rspam01 X-Stat-Signature: u5nhqxosryh1ynq9jsymumkd5kgusc8y X-HE-Tag: 1673017329-77128 X-HE-Meta: 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 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: On 6 Jan 2023 09:51:00 -0300 Marcelo Tosatti > On Fri, Jan 06, 2023 at 08:12:44AM +0800, Hillf Danton wrote: > > > > Regression wrt V12 if timer is added on the CPU that is not doing HK_TYPE_TIMER? > > Before this change, the timer was managed (and queued on an isolated > CPU) by vmstat_shepherd. Now it is managed (and queued) by the local > CPU, so there is no regression. Given vm stats folded when returning to userspace, queuing the delayed work barely makes sense in the first place. If it can be canceled, queuing it burns cycles with nothing earned. Otherwise vm stats got folded already. Nor does shepherd even without delay. And the right thing is only make shepherd leave isolated CPUs intact.