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 C7517C433FE for ; Tue, 1 Feb 2022 06:33:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234190AbiBAGdm (ORCPT ); Tue, 1 Feb 2022 01:33:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58482 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233754AbiBAGdl (ORCPT ); Tue, 1 Feb 2022 01:33:41 -0500 Received: from mail-ed1-x535.google.com (mail-ed1-x535.google.com [IPv6:2a00:1450:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2BF27C061714 for ; Mon, 31 Jan 2022 22:33:41 -0800 (PST) Received: by mail-ed1-x535.google.com with SMTP id j23so31929325edp.5 for ; Mon, 31 Jan 2022 22:33:41 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:reply-to:references:mime-version :content-disposition:in-reply-to:user-agent; bh=JrzOIwB/15hXdxo9+BD6kYpDhXtGeAQrIT7/EdNyUC8=; b=KiOB8OZmozPHe204e845yU6DhE2s2Wii7ARJYDMRtL14WMcLChXIhgUC8V7Sc6qv3c ygZAa9odMWs+SHECpaMYcYiFX2RKQgy2gueKBEfcNJ2YNd06zKBuVOk2+wzrG2OV99vd 4sLfTzxmDxzPh4V6Wq2X0aTg65IbvVqX02+Ez5Ubeld3riS+YfNItXkYYbyoFQQRp4tO dNJSQ0LVj5ZatkwM46bWaMzeU3p9gwsJVctEqK2BJvWb2IIzwTsTNzmGniU3pC1eR8hP 3aQWB6BGEjSe11DSbIpQAn7imGk3yayzkeSqRzjHIs5hxqewKmSPM4FEPgPLBrc2wHZy rOhA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:reply-to :references:mime-version:content-disposition:in-reply-to:user-agent; bh=JrzOIwB/15hXdxo9+BD6kYpDhXtGeAQrIT7/EdNyUC8=; b=YhAkelgNO0J2aso88eyW14OJXWVgo0ji/dt3VInqfcI2lwOgAx3IJ9CuiSMqbKix2p E93FCnIcZ20WBmWAo42B36oAn8+2LQ1GH4fw/VxQNBHU1qaIece9FuVM7eDEOyNsKmcp vqqK0eD3tA4Dr9zpO4saB3o6DKZT2wKc75qE7OVQ+03+aekqTjxQKpp8vCrItfIP0N2t dEvUgBhG0ZjsWKQcf1TchN/t8xyBfZm7uytGMW5D8GSgDlunEv9JiNPMHqG4I+jTNUTR EsvIm27wdyeFIj/RXZQ5HyJ8caGQa1QH8u3Hj5gkZRR7630lO9ZKEhq5h2ZWR5NTNi1s Q7QQ== X-Gm-Message-State: AOAM532J2PL8KCH2S3S0qWkQDzKM4wFfUEAPJlwaiSjYE6GrlrgLCEk/ KZnJVV+UAXYVB0PWIwm3pCY= X-Google-Smtp-Source: ABdhPJz0L77NhTpN2CaRbV3UMUQngiAZFds2CfrdJ3MxZAJnDbRhUE2zdRKHZYmco5hzlmHATJSNsw== X-Received: by 2002:a50:eb82:: with SMTP id y2mr23327756edr.133.1643697219722; Mon, 31 Jan 2022 22:33:39 -0800 (PST) Received: from localhost ([185.92.221.13]) by smtp.gmail.com with ESMTPSA id fh23sm14300698ejc.176.2022.01.31.22.33.39 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Mon, 31 Jan 2022 22:33:39 -0800 (PST) Date: Tue, 1 Feb 2022 06:33:38 +0000 From: Wei Yang To: Michal Hocko Cc: Wei Yang , akpm@linux-foundation.org, mgorman@techsingularity.net, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/memory_hotplug: build zonelist for managed_zone Message-ID: <20220201063338.u4ux2jsgctuo7tex@master> Reply-To: Wei Yang References: <20220127012023.18095-1-richard.weiyang@gmail.com> <20220129002628.2cwr35glahq5f5md@master> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 31, 2022 at 11:24:48AM +0100, Michal Hocko wrote: >> >> This patch restore the original behavior by using the same criteria to >> >> add a zone in zonelist during memory hotplug. >> > >> >Why? >> > >> >> In case we online a populated zone, but not managed. Then this zone will not >> be in zonelist. Right? > >yeah. We can theoretically end up with a zone without any managed menory >on the zonelists. But my primary question is why do we need this change? Currently I don't see a real case for this. >Does it fix any existing problem? Does it make the code easier to >read/understand? Does it improve performance? Every patch should have a >justification. Your changelog merely lists the history and then states >the new behavior without any explanation of why that is needed or >desired. See? I don't have such reason now. >-- >Michal Hocko >SUSE Labs -- Wei Yang Help you, Help me