From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from invmail4.hynix.com (exvmail4.hynix.com [166.125.252.92]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 633D517BD6 for ; Fri, 16 Feb 2024 09:11:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=166.125.252.92 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708074723; cv=none; b=J/42BKfAT6lzZWw6WcaWa70SmMtQTSry7z26QdrFb3WU9zoWLwBYWAOnerXR/14ZbnTmnTsHhRau0VuIcLdBlyx2Pen6FegX+fsszKzd0dP7nFRw0hNLtnIdgZ5Tuc+bVR1a1r4ZtowKd92W2BfQwZk3ERXG87rNqoqDK1E4yoM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708074723; c=relaxed/simple; bh=Ryp7q8VfnYfLCvqepfziSt+wAlGU+XTSlKDD0RP5Vxc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=AcaMqJRRfUaJ494cBi4Yv8Of8CmGtaMJl1E442i/g7l4IONteX+a9v6RQBh1t2xlKTOYwsyMBSx3hynC5y2GHbSlV7VYZnZXFxp0qh4p7gbVJr6eR20copBBStRS2bcY5P/s1RxgGzq36ve6TT7OONznEjok+i0zwaYXZcH/4m8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com; spf=pass smtp.mailfrom=sk.com; arc=none smtp.client-ip=166.125.252.92 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sk.com X-AuditID: a67dfc5b-d6dff70000001748-b0-65cf26d1d245 Date: Fri, 16 Feb 2024 18:11:40 +0900 From: Byungchul Park To: Oscar Salvador Cc: mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kernel_team@skhynix.com, akpm@linux-foundation.org Subject: Re: [PATCH] sched/numa, mm: do not promote folios to nodes not set N_MEMORY Message-ID: <20240216091139.GA75176@system.software.com> References: <20240214035355.18335-1-byungchul@sk.com> <20240216070754.GB32626@system.software.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupjkeLIzCtJLcpLzFFi42LhesuzSPei2vlUg2nHxS3mrF/DZnHp8VU2 i+kvG1ksnk7Yymxxt38qi8XlXXPYLO6t+c9qMfndM0aLSwcWMFmcmVZkcbz3AJPFvo4HTBYd R74xW2w9+p3dgc9jzbw1jB4t+26xeyzYVOqxeYWWx6ZPk9g97lzbw+ZxYsZvFo/3+66yeWw+ Xe3xeZNcAFcUl01Kak5mWWqRvl0CV0bD+4nMBT+4Kn43PGZuYLzO0cXIySEhYCKx9NJndhj7 SGcjM4jNIqAqMf9YP1icTUBd4saNn2BxEQE1iWmvGoHiXBzMAqeYJCZ8vgDkcHAIC4RJ/H2j AFLDK2AhceT/KlaQGiGBXYwS19YsYINICEqcnPmEBcRmFtCSuPHvJRNIL7OAtMTyfxwgJqeA qcTfNTUgFaICyhIHth1nAhkjIdDMLrFi3yOoOyUlDq64wTKBUWAWkqmzkEydhTB1ASPzKkah zLyy3MTMHBO9jMq8zAq95PzcTYzAWFpW+yd6B+OnC8GHGAU4GJV4eA/8OZsqxJpYVlyZe4hR goNZSYR3Uu+ZVCHelMTKqtSi/Pii0pzU4kOM0hwsSuK8Rt/KU4QE0hNLUrNTUwtSi2CyTByc Ug2MXfLJpscN8pi3X5Hv/LVDbdfpyc+9lgZtnnz8crIlS/gz3t15ka+90tdlsCS0NFzLPTCt r1Wis7Ly9tsgxnMLpBu1Vf8f97vp2fL+j4GOvueSbL+nXx93lEws8f24ofrKt/CNtxd/t5mc tbK8U3X356l6eyV2n5NLaZqf0Cy+4ODtTuVjerdmKLEUZyQaajEXFScCAKiRbaKhAgAA X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrKLMWRmVeSWpSXmKPExsXC5WfdrHtR7XyqwaxmXos569ewWVx6fJXN YvrLRhaLpxO2Mlvc7Z/KYnF47klWi8u75rBZ3Fvzn9Vi8rtnjBaXDixgsjgzrcjieO8BJot9 HQ+YLDqOfGO22Hr0O7sDv8eaeWsYPVr23WL3WLCp1GPzCi2PTZ8msXvcubaHzePEjN8sHu/3 XWXzWPziA5PH5tPVHp83yQVwR3HZpKTmZJalFunbJXBlNLyfyFzwg6vid8Nj5gbG6xxdjJwc EgImEkc6G5lBbBYBVYn5x/rZQWw2AXWJGzd+gsVFBNQkpr1qBIpzcTALnGKSmPD5ApDDwSEs ECbx940CSA2vgIXEkf+rWEFqhAR2MUpcW7OADSIhKHFy5hMWEJtZQEvixr+XTCC9zALSEsv/ cYCYnAKmEn/X1IBUiAooSxzYdpxpAiPvLCTNs5A0z0JoXsDIvIpRJDOvLDcxM8dUrzg7ozIv s0IvOT93EyMwMpbV/pm4g/HLZfdDjAIcjEo8vAf+nE0VYk0sK67MPcQowcGsJMI7qfdMqhBv SmJlVWpRfnxRaU5q8SFGaQ4WJXFer/DUBCGB9MSS1OzU1ILUIpgsEwenVANj1u0VNy7b+G5f z8ZiJDNR6WTjjUPOByr+/nk1L2NXeWzGdceUG+ZN8luc/+64LBV3Wf6R2EWrv4WJ9Y+mJJWv Off/ztQGw/qrhcc4birmZj7wj05JnmE7bdUl51MvZrNLiPfuq31Qwt+Rqbzxl+e9mX9uXY/7 8fOSRty05VOtUuK4Nz3bncz/S4mlOCPRUIu5qDgRAArQxHCIAgAA X-CFilter-Loop: Reflected On Fri, Feb 16, 2024 at 08:52:30AM +0100, Oscar Salvador wrote: > On Fri, Feb 16, 2024 at 04:07:54PM +0900, Byungchul Park wrote: > > For normal numa nodes, node_data[] is initialized at alloc_node_data(), > > but it's not for memoryless node. However, the node *gets onlined* at > > init_cpu_to_node(). > > > > Let's look at back free_area_init(). free_area_init_node() will be called > > with node_data[] not set yet, because it's already *onlined*. So > > ->zone_pgdat cannot be initialized properly in the path you mentioned. > > I am might be missing something., so bear with me. > > free_area_init() gets called before init_cpu_to_node() does. > free_area_init_node() gets called on every possible node. > > free_area_init_node then() does > > pg_data_t *pgdat = NODE_DATA(nid);, > > and then we call free_area_init_core(). > > free_area_init_core() does > > free_area_init_core() does > zone_init_internals() > > which ends up doing zone->zone_pgdat = NODE_DATA(nid); > > If node_data[] was not set at all, we would already blow up when doing > the first > > for_each_node() > pgdat = NODE_DATA(nid); > free_area_init_node(nid); > > back in free_area_init(). It seems that I got it wrong about the reason. Let me check it again and share the reason. Just in case, this patch is still definitely necessary tho. Byungchul