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 23926C28B2E for ; Mon, 10 Mar 2025 08:28:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 37014280002; Mon, 10 Mar 2025 04:28:25 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2FC62280001; Mon, 10 Mar 2025 04:28:25 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 17492280002; Mon, 10 Mar 2025 04:28:25 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id EA0D3280001 for ; Mon, 10 Mar 2025 04:28:24 -0400 (EDT) Received: from smtpin17.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 1857D160BF3 for ; Mon, 10 Mar 2025 08:28:26 +0000 (UTC) X-FDA: 83204964612.17.78C073F Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf06.hostedemail.com (Postfix) with ESMTP id 6A263180009 for ; Mon, 10 Mar 2025 08:28:24 +0000 (UTC) Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=Dt+61OBu; spf=pass (imf06.hostedemail.com: domain of rppt@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1741595304; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=csWbwEiXnN3k3hOiqezshSsmwqgj7zqeo9XkzzIm5Ds=; b=G8kMSGjhhUe15PdMTb8P7zeZTz+x2ExzPvlQ8ccJYDTsfL+KY9OcwN3LGXtXBNH3SgfbNJ r5WgHfhvaafhmF5SqOS6rBS7xxKIBgy/rIcR8re4eCk3gAdsfcID5Pjmo9CPYnbfRFDIYF fOOWeNttZA5JeRJkq9K9JNL0FrrhO/M= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1741595304; a=rsa-sha256; cv=none; b=Ih1k1F6VaWhG7YOe+CgpiuMmZt8M/WseE/wvp98s00AXCkkatfWI50CXSQXMz0LlJxqCe6 gkNurfQzECYAiVP9RoPeb7cYbWUZqg7VdEkXB9Ubwx+jkndUEpVRiDrgmJea+Hl+gRRHaa LSTLoZgyMX1js5kj0SzmsnQaCyHkwNk= ARC-Authentication-Results: i=1; imf06.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=Dt+61OBu; spf=pass (imf06.hostedemail.com: domain of rppt@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=rppt@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 8AAEF5C488E; Mon, 10 Mar 2025 08:26:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20474C4CEED; Mon, 10 Mar 2025 08:28:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741595303; bh=7uCFQcex+j6cpQPJF/6LfRBEaDs9jns/4ey91A2Sm5Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Dt+61OBuhSx0XzWa7kuR97NtRZolf+Ni76hFMdBs33YLt/1k+RMsxShKq8ywE5izv Xq0lyi+y7SJzKRcmF6pLe0/pMIp2CN1NtohvIhp4Lfz70fUXaKP8fdlcvDgL6nFqFz egPccLakn6UNDZwAc49vCsDGQvAccm2S6VOGcQu87kNkGYRfcWBfvdZMHBeMdQgSn4 J/L+XCc+GdJd0FpcGKyrg/IzPOfmKo79PxsSU2iqjEbBsVqKufsF8EZdPd3pBHuFq6 ipnF9XH2wTyTICRsMyZozegPxkb/EOVYqYIAdiNDHZduHzAW48E8qnjKEoT8Kf1pgw OUmx0WBZnksfg== Date: Mon, 10 Mar 2025 10:28:02 +0200 From: Mike Rapoport To: Wei Yang Cc: linux-kernel@vger.kernel.org, Alexander Graf , Andrew Morton , Andy Lutomirski , Anthony Yznaga , Arnd Bergmann , Ashish Kalra , Benjamin Herrenschmidt , Borislav Petkov , Catalin Marinas , Dave Hansen , David Woodhouse , Eric Biederman , Ingo Molnar , James Gowans , Jonathan Corbet , Krzysztof Kozlowski , Mark Rutland , Paolo Bonzini , Pasha Tatashin , "H. Peter Anvin" , Peter Zijlstra , Pratyush Yadav , Rob Herring , Rob Herring , Saravana Kannan , Stanislav Kinsburskii , Steven Rostedt , Thomas Gleixner , Tom Lendacky , Usama Arif , Will Deacon , devicetree@vger.kernel.org, kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org Subject: Re: [PATCH v4 02/14] memblock: add MEMBLOCK_RSRV_KERN flag Message-ID: References: <20250206132754.2596694-1-rppt@kernel.org> <20250206132754.2596694-3-rppt@kernel.org> <20250218155004.n53fcuj2lrl5rxll@master> <20250224013131.fzz552bn7fs64umq@master> <20250226020915.ytxusrrl7rv4g64l@master> <20250310075627.5hettrn2j2ien5bj@master> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250310075627.5hettrn2j2ien5bj@master> X-Rspam-User: X-Rspamd-Queue-Id: 6A263180009 X-Stat-Signature: 66jdak3bfd3rwiwdxe5d33ictj4ne1my X-Rspamd-Server: rspam10 X-HE-Tag: 1741595304-728356 X-HE-Meta: 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 zg6BR15T us8rlbpmk4Caun89oe14KU6vCq/ay3CBd5Xt53qj/Y6uJLB8nWoq2W64M7vt5hT8aIrJmAxf+3Wpus7wEqLAUrqmvWMpLWj41o36r0TovS7ZToMhA/YfHCWE2IgiltskgKIRD9I+XmeXipCZG6Q7I0HsGnDb1J0pvCuH6pBPoS1cbYLA9GNAUBw8ADuVxD+kNr7bnGUxHGEtx1A3lBbVQ4VvFBYfC1/A6INlRZlw9ZkUGOZFZ/f0M/tQmu9Avu7stjk7n9qARaON8n3c5bakbaZcpyNpB6KixypxdFA2mXMeMmPuKohtnxJMKwNTexO39ElSUJ36xDYAh3q7x8TVhGdfXJvaXv20Lyf/sXo7FBrkzrwbhoqbEI8Yx3x1oNxe/53uM 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: Hi Wei, On Mon, Mar 10, 2025 at 07:56:27AM +0000, Wei Yang wrote: > On Wed, Feb 26, 2025 at 02:09:15AM +0000, Wei Yang wrote: > >>> > >>> From the above call flow and background, there are three cases when > >>> memblock_alloc_range_nid() would be called: > >>> > >>> * If it is called before (1), memblock.reserved's nid would be adjusted correctly. > >>> * If it is called after (2), we don't touch memblock.reserved. > >>> * If it happens between (1) and (2), it looks would break the consistency of > >>> nid information in memblock.reserved. Because when we use > >>> memblock_reserve_kern(), NUMA_NO_NODE would be stored in region. > >>> > >>> So my question is if the third case happens, would it introduce a bug? If it > >>> won't happen, seems we don't need to specify the nid here? > >> > >>We don't really care about proper assignment of nodes between (1) and (2) > >>from one side and the third case does not happen on the other side. Nothing > >>should call membloc_alloc() after memblock_free_all(). > >> > > > >My point is if no one would call memblock_alloc() after memblock_free_all(), > >which set nid in memblock.reserved properly, it seems not necessary to do > >__memblock_reserve() with exact nid during memblock_alloc()? > > > >As you did __memblock_reserve(found, size, nid, MEMBLOCK_RSRV_KERN) in this > >patch. > > > > Hi, Mike > > Do you think my understanding is reasonable? Without KHO it is indeed not strictly necessary to set nid during memblock_alloc(). But since we anyway have nid parameter in memblock_alloc_range_nid() and it anyway propagates to memblock_add_range(), I think it's easier and cleaner to pass nid to __memblock_reserve() there. And for KHO estimation of scratch size it is important to have nid assigned to the reserved areas before memblock_free_all(), at least for the allocations that request particular nid explicitly. > -- > Wei Yang > Help you, Help me -- Sincerely yours, Mike.