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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Zi Yan , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Alistair Popple , Axel Rasmussen , Yuanchu Xie , Wei Xu , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , LKML , linux-mm@kvack.org References: <20260410032333.400406-1-jhubbard@nvidia.com> <87h5p4isbb.fsf@DESKTOP-5N7EMDA> <51168a90-d6ad-4429-8043-3dfdd81cb9a3@kernel.org> <878qafix71.fsf@DESKTOP-5N7EMDA> Content-Language: en-US From: John Hubbard In-Reply-To: <878qafix71.fsf@DESKTOP-5N7EMDA> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BYAPR03CA0013.namprd03.prod.outlook.com (2603:10b6:a02:a8::26) To DM3PR12MB9416.namprd12.prod.outlook.com (2603:10b6:0:4b::8) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM3PR12MB9416:EE_|DM4PR12MB6590:EE_ X-MS-Office365-Filtering-Correlation-Id: 9b968cf3-b633-446b-6337-08dea0e3665b X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|376014|1800799024|56012099003|22082099003|18002099003; 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The wait uses a one-second timeout. An >>> >>> Is the one-second timeout appropriate for all users? Do some users >>> prefer fail-fast behavior instead? If so, should we add another FOLL >>> flag to support a timed wait? >> >> We should avoid a FOLL flag to affect that behavior. FOLL_LONGTERM >> already implies that things could take a while. > > Yes. I am just not sure whether one-second is OK for all users. > >> So we have real examples were failing is even desirable? :) > > Hi, John, > > Could you do some research on this? > Yes, absolutely! Great set of questions from everyone, much appreciated. I'm hoping to have some answers to post before LSF/MM, these are not too hard to answer. thanks, -- John Hubbard