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Wed, 11 Aug 2021 07:05:47 +0000 Received: from HQMAIL109.nvidia.com (172.20.187.15) by HQMAIL101.nvidia.com (172.20.187.10) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 11 Aug 2021 07:05:47 +0000 Received: from sandstorm.attlocal.net (172.20.187.6) by mail.nvidia.com (172.20.187.15) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Wed, 11 Aug 2021 00:05:46 -0700 From: John Hubbard To: Andrew Morton CC: Heiko Carstens , Vasily Gorbik , Christian Borntraeger , LKML , , , , John Hubbard Subject: [PATCH v2 0/3] A few gup refactorings and documentation updates Date: Wed, 11 Aug 2021 00:05:39 -0700 Message-ID: <20210811070542.3403116-1-jhubbard@nvidia.com> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 X-NVConfidentiality: public X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: fb11b7c3-0756-4bda-ead4-08d95c96721c X-MS-TrafficTypeDiagnostic: BY5PR12MB4145: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:9508; 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X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Aug 2021 07:05:47.7314 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: fb11b7c3-0756-4bda-ead4-08d95c96721c X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.112.36];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: BN8NAM11FT013.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR12MB4145 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org OK, here is v2 with changes as recommended by Christoph Hellwig and Matthew Wilcox (thanks!): * Changed refs to @refs, and added some more documentation as well. * Completely removed try_get_page(). (I'm adding more people and lists to Cc, because of those call site changes.) * Reversed the logic in try_grab_page() to make it a touch more readable. Also, this has been rebased to today's linux-next (next-20210810), and re-tested on that. Here is the v1 cover letter, edited slightly to keep up with the latest story. While reviewing some of the other things going on around gup.c, I noticed that the documentation was wrong for a few of the routines that I wrote. And then I noticed that there was some significant code duplication too. So this fixes those issues. This is not entirely risk-free, but after looking closely at this, I think it's actually a useful improvement, getting rid of the code duplication here. However, it is possible I've overlooked something. I did some local LTP and other testing on an x86 test machine but failed to find any problems yet. And the original v1 is here: https://lore.kernel.org/r/20210808235018.1924918-1-jhubbard@nvidia.com John Hubbard (3): mm/gup: documentation corrections for gup/pup mm/gup: small refactoring: simplify try_grab_page() mm/gup: Remove try_get_page(), call try_get_compound_head() directly arch/s390/mm/fault.c | 2 +- fs/pipe.c | 2 +- include/linux/mm.h | 10 +----- mm/gup.c | 79 ++++++++++++++++++++++---------------------- 4 files changed, 43 insertions(+), 50 deletions(-) --- 2.32.0