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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F392CC2BD09 for ; Tue, 9 Jul 2024 04:15:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:MIME-Version:Content-Type: Message-ID:In-reply-to:Date:Subject:Cc:To:From:References:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=EJpQ32FMFpHGLNZs2+50f1LMgw7Iy4rRhOXMk7E95dw=; b=fgefpAumez3utUJB/3LQw6rvfd rUUCXKMNfTo7D2BQPQ223V8Z3QMGekPryjkzHVDOya9KQDeQ21PPeD4iK33p0ZIf/KZQOsyDcNqYZ /iIf9/CYNrnvlg5q1sfj9xo7DAjbYZ4aAuhoEQ3TmMU7gMAabMFO79w2d0KeNozWPW/mdBEhJXTIS c7mRz+79ft5mrj97T6lcEDEgs2oX/9y169VogOb0sS8mEolJK+d09Za/U1x7Q/xXD8n8omDQlqVDT SBegGRR0zoi8atdYUQsafuGAxuqj+1uGovcLsuj5d7Zg6PLQLteZvToRhAU39aYTxtVruC1Ll9ILl Mj94eo5Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sR2GY-00000005pUN-3NKK; Tue, 09 Jul 2024 04:15:46 +0000 Received: from mail-dm6nam12on20600.outbound.protection.outlook.com ([2a01:111:f403:2417::600] helo=NAM12-DM6-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sR2GI-00000005pNT-3k9j for linux-arm-kernel@lists.infradead.org; Tue, 09 Jul 2024 04:15:32 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=WI74JGf1uSwO1QGu+PAY+CRUy6LMQnAVi342cHknl67Zz2r6XJYFbPTg8YZbo9ZvBZ6l0Iz0aeKWjik8Rf/uzLmIdgBbsRicOGJycVqYdH3zjjlfYd0FtsVfD/1lyGYDsgeB4kSkxqSqaGiWzmhOp34H6GlHpk9pp6+T3Ie3CHSbC1GD6zF2W1KDtSSpVsQLn7f4jjwX5gNltMZS21NGi2Gnsb/3yGVgZspdBH2MjiYzyqmWAfvPVJvytgpePoI9JPFiZK05Iyzh+UuCYVjM66bia9nlSfO3h672vkcpBUE23w+01n91eyKRpZ+vYZFkJKYzPUPpyk85+jv5X2cTyw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=EJpQ32FMFpHGLNZs2+50f1LMgw7Iy4rRhOXMk7E95dw=; b=b/4ClP6tnCGMh3nWhhoxB+ojWyfzLb+4FHgToEsBUluwLUuK5bN2saidqtj0xldVZUsWw85oTLEhqFaHEZaDy7RXG4i7J/rZjo7y3m/KDi8jGmk/MOp6L12pxjdQMeJvvwiJsuJhoOl76CGgRkWkg2J2vu+srfahHF971LC7tKOyA3fObHrQjXmD1PcELc3yjiAUv5mCbIhETr9Oe6yqxcCpAypp251DWFHRZPsE8wYkTlNlDaPI0kJMBBUb6At0QTxwxXwVUeQ3pFqW7nqr0q2ticL6BiiMdi+LTUPoXNhXc15St4hJ8140uMhhdocTp+NJFSISObADc8Pnoo6qCg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=EJpQ32FMFpHGLNZs2+50f1LMgw7Iy4rRhOXMk7E95dw=; b=Mzzeyy8a3R9tfvAmseeqSZAGMMGSUkPEDrOCk4apbks7Wig8ewBbg47O5rUoW3bgetawEsZRg1l6ViAE9FxE1vd+khMAW6WifxcY23hphZv+KOHOItspaL2wyFU8n/WLVYt09+s8ahIvAYHTAKr9YC4lgD5CAF9ACuhfJ7Dfy5ILv5bd1Hu6+OAtXEOgvtnpdVr9XgNrGl5gfKiZnJQGmHZOuHvx+srd4Cju7F9I+cY/Yds6iweAqgJcE7gFz9Ad57TF2oKfg9hegIZBx22ujuTL+i+2sQKsaPavBOcnLFyi2bz4fCw7zPfCpokJ0Ezs1Sl7dOLYgREyMn/pWkBtCA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nvidia.com; Received: from DS0PR12MB7726.namprd12.prod.outlook.com (2603:10b6:8:130::6) by CH2PR12MB4199.namprd12.prod.outlook.com (2603:10b6:610:a7::13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7741.35; Tue, 9 Jul 2024 04:15:19 +0000 Received: from DS0PR12MB7726.namprd12.prod.outlook.com ([fe80::953f:2f80:90c5:67fe]) by DS0PR12MB7726.namprd12.prod.outlook.com ([fe80::953f:2f80:90c5:67fe%2]) with mapi id 15.20.7741.033; Tue, 9 Jul 2024 04:15:18 +0000 References: <400a4584f6f628998a7093aee49d9f86c592754b.1719386613.git-series.apopple@nvidia.com> User-agent: mu4e 1.10.8; emacs 29.1 From: Alistair Popple To: Peter Xu Cc: dan.j.williams@intel.com, vishal.l.verma@intel.com, dave.jiang@intel.com, logang@deltatee.com, bhelgaas@google.com, jack@suse.cz, jgg@ziepe.ca, catalin.marinas@arm.com, will@kernel.org, mpe@ellerman.id.au, npiggin@gmail.com, dave.hansen@linux.intel.com, ira.weiny@intel.com, willy@infradead.org, djwong@kernel.org, tytso@mit.edu, linmiaohe@huawei.com, david@redhat.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, nvdimm@lists.linux.dev, linux-cxl@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-ext4@vger.kernel.org, linux-xfs@vger.kernel.org, jhubbard@nvidia.com, hch@lst.de, david@fromorbit.com, Alex Williamson Subject: Re: [PATCH 11/13] huge_memory: Remove dead vmf_insert_pXd code Date: Tue, 09 Jul 2024 14:07:31 +1000 In-reply-to: Message-ID: <87zfqrw69i.fsf@nvdebian.thelocal> Content-Type: text/plain X-ClientProxiedBy: SY5P282CA0089.AUSP282.PROD.OUTLOOK.COM (2603:10c6:10:201::19) To DS0PR12MB7726.namprd12.prod.outlook.com (2603:10b6:8:130::6) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS0PR12MB7726:EE_|CH2PR12MB4199:EE_ X-MS-Office365-Filtering-Correlation-Id: 66c06f32-d845-4b64-e016-08dc9fcdbe14 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|7416014|376014|366016; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?/KqtXncNXswKq8dz6tZVC8OIZJdSdJNugY7sdJfgwAhPRNQihtqM6fx/7X2W?= =?us-ascii?Q?f2vneJSLYAZE4goVe2Wls9eNYrU/S9YpnZaSliMC6DgjzyTOBH7tK/CMXpXB?= =?us-ascii?Q?WnvCXPaczAB+BiRAoCASMiGKNCbt1nkQC3Hz84vKr/CAxuzSaE+Kkf1PNW4m?= =?us-ascii?Q?K2kNrfKfs9QtaY5rI0ftRbGzqwK8gfOI07hEL4fQmS+KaeSZVl8C+HFgzOgi?= =?us-ascii?Q?ldJ6+uZs+q7cFaqKkYgmzfZK82sucVKJhlel60up8jFi3Esp+wv5jDmxaNkz?= =?us-ascii?Q?ApzF+Dfa8uweZ++b0dOCxmJ8owWvfMHKuS068kcmqts57mKRsNCeGQmpiOPv?= =?us-ascii?Q?y4KoeAF3hfa++g8CyXTY324Il7zUBOTMQBJMFBtLqgAnLFtBVK+m6vXkKTON?= =?us-ascii?Q?ONyPWJwes/q5QvaDAisxUqUpu1Ms0vqzqdEwzXUAwHrdl4AGnVapMxSYYhNl?= =?us-ascii?Q?XGgau8VwCh+TQ6XvTaRiMaPJfDAC0l0aZO3NYeQQeQdMUB6RSB9mI50z5BYc?= =?us-ascii?Q?y0cIZR0ZTI05FhFfPRlXvbeUTUb4TXGmQb4g+4Oy+u3ruBNAOUbRPvSdSaf1?= =?us-ascii?Q?FMBMP0vKsdup1PruRU+GYd2IO9HKaxN+rpqxYqsDOac2gAyG4C3pGtkYksQS?= =?us-ascii?Q?skvo7jYHyNktJbIqHFX2FGAqjYl6+RdwYpyZBgAYIKWtLfqeJbWQfc0CA5B1?= =?us-ascii?Q?oyNUxG4zdunNJACPqDEasTvpZC9crq4GB99uUggiEX7RLDFnHWjAGdCz1bHC?= =?us-ascii?Q?yh/fhDnRd/uFV07aPj8gi3kC3Nwez0VhXv/SzqryXfELcLjpr9jQ5t7LiUMw?= =?us-ascii?Q?mCdkh+kXNVloUHLS9Mlo2i9C1FB37vL+Xl+rHBRsUkNFkOSlTPDxuq6SxkXI?= =?us-ascii?Q?ixXf87HwTx36j3q7jC5vUhzxW4pynOnB8UqyvWDXrs+oeTCJZJTTZigi3mJo?= =?us-ascii?Q?f78h/FZFoPp+O4NPK/edlLhBZbfqbFG00nJsMK+Zb8EWC4pWIfBU4Hy6YWrr?= =?us-ascii?Q?7Ln+0WKCfzI/NPrvhc/ynkJGklu4iTNaWyzJUoLCQn1/d/Q+2zeHBPvwL03k?= =?us-ascii?Q?zmTVmQF4Rk3gRsGe6NuUMY6LYxEr0XNsMC9D8QJsriBfnV1Ny2jPbo9Z4A4R?= =?us-ascii?Q?oMbo+gKcTVIIbscIZteRmMI1pEnXLdx6MwIrWmiVERzG4VMzAbjOX397iA7I?= =?us-ascii?Q?Z/SziTgqsDWaqXO6GXCaa52iGH6ITGu+R6nAyzFPF858pD23yl0g/x36JmL6?= =?us-ascii?Q?5dqT9jl1KMUQhAxNKW4cuhKSfGwDBUCoJNQszbcBBjOSwJ1vBK0NrHdn/qZN?= =?us-ascii?Q?aLUQdGSOsvkCsoCJxbWJadpj9hCMrJL7k81Dp3uYJ+yRcw=3D=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DS0PR12MB7726.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(7416014)(376014)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?RwhTnUQ3vfGPzBiv3UDrShAD9/YYzhxQJN52lVMLB84KOgdb74dRvL8I9KOU?= =?us-ascii?Q?SF5/JOaZMQ3Wfk3/6iI6v1C99MGaVFVteO83CFEat3NwUO22ihGh139P6Xc3?= =?us-ascii?Q?ANI9w/XifixVWYRbdJJsb6fzNEdN8uweQBjX/CHszh6NJ6Wb37Fu9jKJ4GhU?= =?us-ascii?Q?UK7cUmteMLEMu9Xd8K6/w7kw5sdm9KSSPzKtUxIuXv3hEW1iSvBpVBylLsVt?= =?us-ascii?Q?ETIZo+KxOP/jCL2PR0iTKpU3Uy2LO8ojE68BllKw9bvJa+BsMIPOJWY13N1D?= =?us-ascii?Q?JRdeiNkAI9ZOZqC/7iDTZUIPEEdiSMFg/lAKXf5fVUOS+TFDvInMQKdYthWn?= =?us-ascii?Q?x+kgPOzl43DQ+MXVdgCYN46MOB2xPlMNgncfihcs6StfHH36vLKd7EAqdLi8?= =?us-ascii?Q?rp2nKTpDOjrAGfD5dOLL3M8n0YmXpAjlDUPnetfmwXXqCOmXcrdBSlmZqBbd?= =?us-ascii?Q?s/w/ttcjUWtcrkQZd7R+OrZm9oVXiWNQ3JR0AdkacP4wHSlPTNb8FhrW3i2F?= =?us-ascii?Q?E2kkAQaqZd5sMmDeaoTR8199AJH9BAPzu7gODjrWfOYMFOy/iSvtfLVaX86i?= =?us-ascii?Q?avZMluPY0a0RnNq84w4rX1mLR86Z8VisjpmC58U99el2+D4XCv11Nigk079j?= =?us-ascii?Q?os5vg0sipHR5a7VFilJ7zFo4oLTvrkgFW87LJF3AEpAy5Hc6i5LoUGAfye+q?= =?us-ascii?Q?/7dSjOMVwkD5/a9Lf4pm+zLchr6L2ghl7/8nZE5kxINwOTYCcwgs0ZkT0HxJ?= =?us-ascii?Q?mg1lIBXX4Yw2MkhA9S7XtdT416y1nDMg74DL5b0D/Ssp8iIaW/4TyxbSwxS3?= =?us-ascii?Q?8DAf9+MVuAkDAIKLI+IKp9vH/fJTizEM8vvi2UWO5HmIyFvhFD4tUAaJ1Xyt?= =?us-ascii?Q?/FonYuomE2AgSsQM5XSN6zMgktMBKDxma2Wvgd83nZc7wJKT6iC9D6S0s0/c?= =?us-ascii?Q?Ic8w00bdgkl9wJUY36dnk0zugz/nlRW8X2iYZ3He60o/Uz1HxYK1tBcNHxVe?= =?us-ascii?Q?wI73sKWQN42m5QBPpWxtLBulgIoRJqndVOd8drUqrOLJBVeLA3etJdD//BTD?= =?us-ascii?Q?7V0D2+4iV5pDpapOLawRUI7NeZ2Qb32MpoLV6vNIHXw1ooC039FDvw3inTsb?= =?us-ascii?Q?DpTaId0LRQPD/HdRPRmsyzo6+blzJpnEhQZ5zxpU4YeDy+DldjklGjYBi7Y+?= =?us-ascii?Q?Ofkvpvf7XBgMJjdeALsPMpKEMG92yNvn2sRKBxTBBge0F3wggReKob4wowsT?= =?us-ascii?Q?MYUqVbNIz2gpLYHjUcJOOVX9KJUV8rim+34+A539XueK/WejDDzbZprYaVDi?= =?us-ascii?Q?7y0k/wo/hrxW9LiT1VXwsRXiH3v7FHzVfCsq8WY1aGE38T9alVJf0RIRk1EK?= =?us-ascii?Q?f73SJU4/rtO+5d8Mv+73s5JIqAmkd7LmiSjMwOHKD2/UCXewsKJ0JhOt1pf6?= =?us-ascii?Q?rQMQRnH4DoRnqxfxetS402q7HyAA9j/OeKcR59fKkQuueRuQdOZArL3nVD6b?= =?us-ascii?Q?nhUa5EuCkUtiVrCUsst3mamVgmmFb+XMU5DNAJxHNhluNIfLiZuJ4J8xrAGs?= =?us-ascii?Q?Xkgt2lZ5Kt4lWpSxIGM2l6WrmRJtqBm1bTrpjLPs?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 66c06f32-d845-4b64-e016-08dc9fcdbe14 X-MS-Exchange-CrossTenant-AuthSource: DS0PR12MB7726.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Jul 2024 04:15:18.6781 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: bcjuqAtBP75ly7izmtSUD7FBHGJhXw9TRfoqIc1KQRttqJR7IN5tn5gCYrs00TH3duu9vdS6tsvK8/CPXS3NuQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH2PR12MB4199 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240708_211530_944543_FED49307 X-CRM114-Status: GOOD ( 20.50 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Peter Xu writes: > Hi, Alistair, > > On Thu, Jun 27, 2024 at 10:54:26AM +1000, Alistair Popple wrote: >> Now that DAX is managing page reference counts the same as normal >> pages there are no callers for vmf_insert_pXd functions so remove >> them. >> >> Signed-off-by: Alistair Popple >> --- >> include/linux/huge_mm.h | 2 +- >> mm/huge_memory.c | 165 +----------------------------------------- >> 2 files changed, 167 deletions(-) >> >> diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h >> index 9207d8e..0fb6bff 100644 >> --- a/include/linux/huge_mm.h >> +++ b/include/linux/huge_mm.h >> @@ -37,8 +37,6 @@ int change_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, >> pmd_t *pmd, unsigned long addr, pgprot_t newprot, >> unsigned long cp_flags); >> >> -vm_fault_t vmf_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write); >> -vm_fault_t vmf_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write); >> vm_fault_t dax_insert_pfn_pmd(struct vm_fault *vmf, pfn_t pfn, bool write); >> vm_fault_t dax_insert_pfn_pud(struct vm_fault *vmf, pfn_t pfn, bool write); > > There's a plan to support huge pfnmaps in VFIO, which may still make good > use of these functions. I think it's fine to remove them but it may mean > we'll need to add them back when supporting pfnmaps with no memmap. I'm ok with that. If we need them back in future it shouldn't be too hard to add them back again. I just couldn't find any callers of them once DAX stopped using them and the usual policy is to remove unused functions. > Is it still possible to make the old API generic to both service the new > dax refcount plan, but at the meantime working for pfn injections when > there's no page struct? I don't think so - this new dax refcount plan relies on having a struct page to take references on so I don't think it makes much sense to combine it with something that doesn't have a struct page. It sounds like the situation is the analogue of vm_insert_page() vs. vmf_insert_pfn() - it's possible for both to exist but there's not really anything that can be shared between the two APIs as one has a page and the other is just a raw PFN. > Thanks,