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 7E408C48BEB for ; Wed, 21 Feb 2024 22:34:42 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DD5DB6B0081; Wed, 21 Feb 2024 17:34:41 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id D86BF6B0085; Wed, 21 Feb 2024 17:34:41 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C7E356B0081; Wed, 21 Feb 2024 17:34:41 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id B59B96B0081 for ; Wed, 21 Feb 2024 17:34:41 -0500 (EST) Received: from smtpin08.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 63869C0BEF for ; Wed, 21 Feb 2024 22:34:41 +0000 (UTC) X-FDA: 81817266762.08.A045C5B Received: from sin.source.kernel.org (sin.source.kernel.org [145.40.73.55]) by imf17.hostedemail.com (Postfix) with ESMTP id 18A1B40010 for ; Wed, 21 Feb 2024 22:34:38 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=vD06nTR3; dmarc=none; spf=pass (imf17.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1708554879; 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-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=pysZ0HjmrV0+oP1bvmVXBYk9RLvJ1TrQQeR4JycTieY=; b=CywGG6/fLQxccEFvHwLd5bRYXgqy7RXKNN/vnBg5/pCN/qVK++kcB/Bk/S2ZBz5K7UTTH6 EZiNiOK4ufd8LuyaHv0pKFobRhbSlPMALFQrX8FgP+0JzOIrH2yZvrFzATNI8nfYY9DEwX QZLaVffpuFAqSqnmFJtOL7Tfg2BHXZc= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=vD06nTR3; dmarc=none; spf=pass (imf17.hostedemail.com: domain of akpm@linux-foundation.org designates 145.40.73.55 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1708554879; a=rsa-sha256; cv=none; b=EODK/0+3meHyhr/AclnX2ZQMxU5PBF1lV4z8cEVFDr4ibi/VZYTsK+5LMSufJUNFxp36TS 2A0qYGwDlXWgkhu9qbWGNFKQNslGA1v9mVoiUOVgwxwqUtc95E7pGWgSVZ2D/RdCdGLUIc Xd9GJFv8LmhA2ixhPYExtlW9G9rA/fA= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 77400CE1EF9; Wed, 21 Feb 2024 22:34:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 98609C433C7; Wed, 21 Feb 2024 22:34:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1708554874; bh=+zk5hI6eB468xurniuk94r8xGqditRkyTx0mc5bS1UM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=vD06nTR3D0yUKcesnUDeXhbozSvt4Wj5bEu9fdSVxs3fw6qAo2esYRmBkRApqad2W S12T0FE3dMln8XypTKVytgG97/t2owzDnEtXzqWiSxoIyrbtK80PMAy4/eED3n9MHU 2Lcc1lkWaEkYQ3uzcc4zlTsYs2i9wqH0EZi/Qmpg= Date: Wed, 21 Feb 2024 14:34:34 -0800 From: Andrew Morton To: Kefeng Wang Cc: David Hildenbrand , Subject: Re: [PATCH] mm: compaction: early termination in compact_nodes() Message-Id: <20240221143434.5ba9efcf6c4dc534d1f1a9f1@linux-foundation.org> In-Reply-To: References: <20240207095841.1648144-1-wangkefeng.wang@huawei.com> <20240208022508.1771534-1-wangkefeng.wang@huawei.com> <20240208131440.e30a650505fac4068ab75ee8@linux-foundation.org> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 18A1B40010 X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: zwzr8kt6dex6854o15mywqbhsowsfcqy X-HE-Tag: 1708554878-828220 X-HE-Meta: U2FsdGVkX199RKyOCbV2agKU40HG96eTk29ghSp7UIHPiqXk0w4vyn011brRv8IDxyUkqjIMECtmq50cPuVwg2Vwl7KajEVOYWIqbeBLUkTmu2Olsr7Ix4rQ3l0NrLfZUzFIgE1bhAYBg+V2bYxUIy9jahh6wa/FgAyMWeO7lXbhJobs72RNFYeiXoT8PkA5XjjuTpkybls2W3fYxpVLYuxhkqSN2gldMfr5TSDeYjZdiKAglb6E876lEDZ6yIDoMfS3sQe0EUmAGf2t2DBlOll0SJn2pVoFq+zgu23V24rRNuUtNmUZp1WyIbOI0ak1rNAiYuKY+6y9pmFwyqZx6zusyLKzg2uGI6V5qPwq0TMeA8yIRhSyuu6431vr1b1mZvtHOqh12/uznm3FUKiKYSCbT1lxr4sL95jHADX5+OfVKF8zVWAJVO/N8k6VroczlJTFPaqUOuLw57lfrQ2JzhiEGS3AudVqcCuSnn93aYMKKX8tqCylwuTy7EamzgsgpZiagV6xxeI7lS2FNPxxTgCoVcbHh/mO+ZRUHHWPMJqL3LAnsd6GHUP6uDgZFZkxrsBxXnMUS6suUIiTUQ+awzZEDSBrVnN4wbR2iKpbQZTeRIssfEe1SfCiaDJ8tI79sCWVMs2EngwUNyrndO+QjFqOYZF3wiKODbQSqVxTJRpvjJAcB1u+JqX3RPoS0OH31Lo6idNBzwVa+b6dZgwLqxmxc3TBNlApRpA/S8bQE/Fst9WHVYEkjQrGdCFrqmEsSAauMf3wex5WsdZgF7WckYx8geVcb1DWA78UlW9qUhKwqHAvnnUf1plnZtrgsV9lD/+qYGhtCFwx8XlPHJ6KYd2p5kjLEr3awr8tqUp1Kcgv1gDrQ3Ki3HxCFrbrYYB5SjHe/QP6NpzWVPXGwHIkdE3vFaI4yLiL9OhypHH8OPgJ1bS7ls71rJTMBpYYklzeIIfy5xikjw7sSx+1egb dtjN1Cty D6b3eoZ7bGQKt219TFsSN/QTR0hI5Ai1oT23pzuQbwttySH045/rx8lc17XmXi7LUDGAHkLANVJC8kXcbFnUu+xndggy31Z/WzVCV13A0pEZ/xQQbgOylteYrQ//OmkAFiNibpdkNZR4T4yTcMEIBoYCLk7zi1rdlNU+mnfWmy1b2AW5uqude6yXjFpCJAY8hU95me56joa286RM7OqJ0NbevsbDnLHCjMfJoOJInzovSpN2r4brL0y3afIj9JLR7GPqvxQGRPzARd36ECJsK0a5FnkF/mcko/1K9j9h5qjZgStU= 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: List-Subscribe: List-Unsubscribe: On Sat, 17 Feb 2024 10:55:10 +0800 Kefeng Wang = wrote: > On 2024/2/12 22:22, David Hildenbrand wrote: > > On 08.02.24 22:14, Andrew Morton wrote: > >> On Thu, 8 Feb 2024 10:25:08 +0800 Kefeng Wang=20 > >> wrote: > >> > >>> No need to continue try compact memory if pending fatal signal, > >>> allow loop termination earlier in compact_nodes(). > >> > >> Seems sensible, but...=A0 why?=A0 Is there some problem which we can > >> demonstrate with the existing code?=A0 In other words, does this change > >> provide any observable benefit under any circumstances? > >=20 > > I'd also be curious why the existing fatal_signal_pending() calls are=20 > > insufficient. >=20 > The existing fatal_signal_pending() does make compact_zone() breakout of > the while loop, but it still enter the next zone/next nid, and some=20 > unnecessary functions(eg, lru_add_drain) called, no observable benefit > from test, it is just found from code inspection when refactor=20 Fair enough. I added the above words to the changelog (this material should have been communicated in the original!) and I'll plan to move this change into mm-stable next week unless someone stops me.