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McKenney" , Steven Rostedt , Masami Hiramatsu , Dennis Zhou , Tejun Heo , Christoph Lameter , Martin Liu , David Rientjes , christian.koenig@amd.com, Shakeel Butt , SeongJae Park , Michal Hocko , Johannes Weiner , Sweet Tea Dorminy , Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , Suren Baghdasaryan , Vlastimil Babka , Christian Brauner , Wei Yang , Miaohe Lin , Al Viro , Yu Zhao , Roman Gushchin , Mateusz Guzik , Matthew Wilcox , Baolin Wang , Aboorva Devarajan , David Carlier , Andrew Morton , linux-mm@kvack.org, Jonathan Corbet , Shuah Khan , Randy Dunlap , Harry Yoo , Hao Li , Kees Cook , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Ben Segall , Mel Gorman , Valentin Schneider , K Prateek Nayak , linux-trace-kernel@vger.kernel.org, Jan Kara , Oleg Nesterov , Alan Stern , Andrea Parri , Will Deacon , Boqun Feng , Hugh Dickins References: <20261111203626.95838-1-mathieu.desnoyers@efficios.com> <20261111203626.95838-7-mathieu.desnoyers@efficios.com> From: Mathieu Desnoyers Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: YT1PR01CA0082.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:2d::21) To YT6PR01MB491026.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:1d0::10) X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: YT6PR01MB491026:EE_|YT5PR01MB912907:EE_ X-MS-Office365-Filtering-Correlation-Id: 97ce6c92-a160-4b8c-8087-08df419162c7 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|366016|1800799024|376014|7416014|261026121527099003|56012099006|4143699003|10067099003|22082099003|261009223027099003|18002099003; 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[...] > None of the non-owner workers can > reach percpu_counter_tree_add() until activation is already complete, so > only the owner worker's percpu_counter_tree_add_owner() calls actually > race with tree publication. Yes, this is a gap in the test. Each remote worker takes the mutex before its next addition. The tree is published by the time it gets the mutex. So the test only covers the owner's additions racing with the publication, not the remote ones. Planned fix for the next round: only every other remote worker activates the tree. The others add right after the release, so their additions race with the activation. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com