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 ED50FC27C4F for ; Sat, 29 Jun 2024 08:32:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0A3406B0088; Sat, 29 Jun 2024 04:32:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0537B6B0089; Sat, 29 Jun 2024 04:32:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E5D6C6B008A; Sat, 29 Jun 2024 04:32:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id C88E46B0088 for ; Sat, 29 Jun 2024 04:32:27 -0400 (EDT) Received: from smtpin26.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 715CAA0CC6 for ; Sat, 29 Jun 2024 08:32:27 +0000 (UTC) X-FDA: 82283259534.26.DC82A48 Received: from mail-ej1-f44.google.com (mail-ej1-f44.google.com [209.85.218.44]) by imf07.hostedemail.com (Postfix) with ESMTP id 7B90840019 for ; Sat, 29 Jun 2024 08:32:25 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=Zalh3lR+; spf=pass (imf07.hostedemail.com: domain of richard.weiyang@gmail.com designates 209.85.218.44 as permitted sender) smtp.mailfrom=richard.weiyang@gmail.com; dmarc=pass (policy=none) header.from=gmail.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1719649926; h=from:from:sender:reply-to: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=d+VvrPgpaPfHFoccfvcF1iCR4CCDCbWjhnfppTz2OoM=; b=om2Y7EDIWZpOhZRtBqloPLyw3tMjn5V8TfshF1TwLTJkvw8DPijIg9uMNkEwRJ/jSWTLZf 1SZmKrY6x/8hn8NtTUJfe+787cmHivUqXt4dsKFOKD9qP/pvIGrBcfcuKL3uEO0cf27ViX JU0VJ/iIxAstef6jnGng77GG9vEU27g= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1719649926; a=rsa-sha256; cv=none; b=QB/QFQyai8T+p+RcnhwNrOYlzYRg7qSaVb3k1UaJ4cJ3T12zagZ4jyeQQpl7mZncxt2lOr jrAbzdpvBfS70VqAJTmi6Y4zvH3aIQCR4YtGy+FXK2zhacUcBrkbI2AkM0ch1OxCRbnh/v 6pGY9KyNePhgDvCC0e3IHJRBfwlrMLk= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=gmail.com header.s=20230601 header.b=Zalh3lR+; spf=pass (imf07.hostedemail.com: domain of richard.weiyang@gmail.com designates 209.85.218.44 as permitted sender) smtp.mailfrom=richard.weiyang@gmail.com; dmarc=pass (policy=none) header.from=gmail.com Received: by mail-ej1-f44.google.com with SMTP id a640c23a62f3a-a724958f118so164674866b.0 for ; Sat, 29 Jun 2024 01:32:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1719649944; x=1720254744; darn=kvack.org; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=d+VvrPgpaPfHFoccfvcF1iCR4CCDCbWjhnfppTz2OoM=; b=Zalh3lR+RdmbcgLXfBHNO1rSoIDR0P1h9SAOuhF00TKKo6jdqWf/XaVFDjROpgLZ0Y 3SaRs4tNvPFE9K9362QHcRDV3J8IChFqEvWD1GUsmpklvau1n4PQ1FpjdHxi7K3iUAUD a23tBgT0CinQ4NRjMjsuQbn5KLX36nTNA6tFgNLNd94knaw6jfvWptdLpFvxm6QfZghC R+E/wYIpq/p+U9CIg1C1nHn3G7obZCRPIW2qSr0R0PTrTMBo1a/bABZqkEhmsyuksa1s B7XU/HnztPWbAdZjWU/x5OGr5lgMMotj92cKYy8aktk2wYTGTeP9T4aTv6+3i7E3fD5d S8nw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719649944; x=1720254744; h=user-agent:in-reply-to:content-disposition:mime-version:references :reply-to:message-id:subject:cc:to:from:date:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=d+VvrPgpaPfHFoccfvcF1iCR4CCDCbWjhnfppTz2OoM=; b=Zi1Po8gDuvNNn6QdEs9ICCzQovF9K/0RhMCOu2uOnyL4tPbxdio938nSNZs4BG7Rn8 Ze5aPbV6GDUlhiqBDchYJW1E1W5iHHMIEgCQJzAmErDtRYjRLkpGgvin1axltsFzOLLi G5JsjsmZqOg76DCS8/ZdbpMIuDOJt6iMBpaoZlOD+kBmboNb7MMRBef/g4vHmAxWWKxL Su3T/m/p3A10pQIvxuHr/5tWMMpwqwrZFYNtoyk8Q15Fz2C4X22T85b6P4DZefCXfCXW osoguuPOsFeR9PfAp2+anKV4T83Dl90aGFT4/fMih+ZVHiIhPwAZyCe37L7hZMH+wuxn Nr3g== X-Forwarded-Encrypted: i=1; AJvYcCV90cWacSjdAygy3ai3eEnDXkQZS/Gdo0TWI28gMYD+sAxzUcFnQA7aVSVff2SEv6xDI3Y9afuUAaoBYy/PFNg78uI= X-Gm-Message-State: AOJu0Yyum6reLDJheFFaPLETIuJ7OVyMEubffTed1zH8b8z4pv0GRZ2M 52SG6b3aWJF2wXqbsL3t4dYXabpYH190drRDAIpqZpXaeUtYeQuz X-Google-Smtp-Source: AGHT+IE1BZMpYMdsegdYQmNpYmQv4Qu7C2FXPtwHTQRutZOeqEeBEjuceC2c6zNjj1W5gnm6/56vhg== X-Received: by 2002:a17:907:7f11:b0:a6f:e5f7:e966 with SMTP id a640c23a62f3a-a7514475b33mr44016266b.45.1719649943535; Sat, 29 Jun 2024 01:32:23 -0700 (PDT) Received: from localhost ([185.92.221.13]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a72ab06531fsm146019566b.100.2024.06.29.01.32.22 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Sat, 29 Jun 2024 01:32:22 -0700 (PDT) Date: Sat, 29 Jun 2024 08:32:22 +0000 From: Wei Yang To: David Hildenbrand Cc: Wei Yang , akpm@linux-foundation.org, rppt@kernel.org, linux-mm@kvack.org, Nathan Zimmer Subject: Re: [PATCH 2/4] mm: not __SetPageReserved on initializing hot-plugged memory Message-ID: <20240629083222.35mebt7kqxiepsgg@master> Reply-To: Wei Yang References: <20240629013322.12364-1-richard.weiyang@gmail.com> <20240629013322.12364-2-richard.weiyang@gmail.com> <9e05d9da-36bd-4094-93d7-1c19eb77df1e@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9e05d9da-36bd-4094-93d7-1c19eb77df1e@redhat.com> User-Agent: NeoMutt/20170113 (1.7.2) X-Stat-Signature: 87uuizibndae5d3cqcbtodwkr6knyg75 X-Rspamd-Queue-Id: 7B90840019 X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1719649945-387870 X-HE-Meta: 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 PMxjmmh7 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000031, 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, Jun 29, 2024 at 08:19:49AM +0200, David Hildenbrand wrote: >On 29.06.24 03:33, Wei Yang wrote: >> Initialize all pages reserved is an ancient behavior. >> >> Since commit 92923ca3aace ("mm: meminit: only set page reserved in the >> memblock region"), SetPageReserved is removed from >> __init_single_page(). Only those reserved pages are marked PG_reserved. >> >> But we still set PG_reserved on offline and check it on online. >> >> Following two commits removed both of them: >> >> * Commit 0ee5f4f31d36 ("mm/page_alloc.c: don't set pages PageReserved() >> when offlining") removed the set on offline. >> * Commit 5ecae6359e3a ("mm/memory_hotplug: drop PageReserved() check in >> online_pages_range()") removed the check on online. >> >> This means we set PG_reserved for hot-plugged memory at initialization >> is not helpful and a little different from bootmem initialization path. >> Now we can remove it. > >It's not that easy for ZONE_DEVICE. > >Also, see mm/mm-stable > >commit 3dadec1babf9eee0c67c967df931d6f0cb124a04 >Author: David Hildenbrand >Date: Fri Jun 7 11:09:36 2024 +0200 > > mm: pass meminit_context to __free_pages_core() > > Patch series "mm/memory_hotplug: use PageOffline() instead of > PageReserved() for !ZONE_DEVICE". > > >commit b873faaa609ab44c223b2327f55d2b6a2ba4ca9c >Author: David Hildenbrand >Date: Fri Jun 7 11:09:37 2024 +0200 > > mm/memory_hotplug: initialize memmap of !ZONE_DEVICE with PageOffline() >instead of PageReserved() > Let me try to understand this. You also tries to get rid of PG_reserved but you want PG_offline instead, because this benefit virtio-mem, right? But I don't get why PG_offline is wrong for ZONE_DEVICE. I may miss some knowledge for it. > >If you want to work on removing it for ZONE_DEVICE, one idea >is to replace all relevant PageReserved() checks by a >more generic function that would check PageReserved() and the zone > > >-- >Cheers, > >David / dhildenb -- Wei Yang Help you, Help me