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Howlett" , Christoph Lameter , David Rientjes Cc: Roman Gushchin , Harry Yoo , Uladzislau Rezki , Sidhartha Kumar , linux-mm@kvack.org, linux-kernel@vger.kernel.org, rcu@vger.kernel.org, maple-tree@lists.infradead.org, linux-modules@vger.kernel.org, Luis Chamberlain , Petr Pavlu , Sami Tolvanen , Aaron Tomlin , Lucas De Marchi , "linux-tegra@vger.kernel.org" References: <20250910-slub-percpu-caches-v8-0-ca3099d8352c@suse.cz> <20250910-slub-percpu-caches-v8-4-ca3099d8352c@suse.cz> <0406562e-2066-4cf8-9902-b2b0616dd742@kernel.org> From: Jon Hunter Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: LO4P123CA0551.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:319::19) To SJ2PR12MB8784.namprd12.prod.outlook.com (2603:10b6:a03:4d0::11) Precedence: bulk X-Mailing-List: linux-modules@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SJ2PR12MB8784:EE_|CH1PPFE5ACC0FD2:EE_ X-MS-Office365-Filtering-Correlation-Id: db5b2a19-581b-4c37-56d4-08de2e5c79f6 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|7416014|376014|10070799003|1800799024; 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My tested kernel has >>> CONFIG_KVFREE_RCU_BATCHED enabled. Any idea or suggestions on what might be >>> causing this, or how to address it? >>> >> >> I have been looking into a regression for Linux v6.18-rc where time >> taken to run some internal graphics tests on our Tegra234 device has >> increased from around 35% causing the tests to timeout. Bisect is >> pointing to this commit and I also see we have CONFIG_KVFREE_RCU_BATCHED=y. > > Do the tegra tests involve (frequent) module unloads too, then? Or calling > kmem_cache_destroy() somewhere? In this specific case I am not running the tegra-tests but we have a internal testsuite of GPU related tests. I don't believe that believe this is unloading any modules. I can take a look next week to see if kmem_cache_destroy() is getting called somewhere when these tests run. Thanks Jon -- nvpublic