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charset=UTF-8 Date: Mon, 17 Aug 2026 20:49:12 +0900 Message-Id: Subject: Re: [PATCH v5 5/5] gpu: nova-core: add ChannelIdPool From: "Eliot Courtney" To: "Danilo Krummrich" , "Gary Guo" Cc: "Eliot Courtney" , "Yury Norov" , "Alice Ryhl" , "Burak Emir" , "Yury Norov" , "Miguel Ojeda" , "Boqun Feng" , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , "Benno Lossin" , "Andreas Hindborg" , "Trevor Gross" , "Daniel Almeida" , "Tamir Duberstein" , "Alexandre Courbot" , =?utf-8?q?Onur_=C3=96zkan?= , "David Airlie" , "Simona Vetter" , "Greg Kroah-Hartman" , "John Hubbard" , "Alistair Popple" , "Timur Tabi" , "Zhi Wang" , , , , , "dri-devel" X-Mailer: aerc 0.21.0-0-g5549850facc2 References: <20260812-chid-v5-0-6c767770b3f4@nvidia.com> <20260812-chid-v5-5-6c767770b3f4@nvidia.com> In-Reply-To: X-ClientProxiedBy: DB8PR06CA0064.eurprd06.prod.outlook.com (2603:10a6:10:120::38) To BL0PR12MB2353.namprd12.prod.outlook.com (2603:10b6:207:4c::31) Precedence: bulk X-Mailing-List: nova-gpu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BL0PR12MB2353:EE_|SJ5PPFF6E64BC2C:EE_ X-MS-Office365-Filtering-Correlation-Id: aba040ac-e002-439c-415f-08defc5591b6 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|7416014|376014|23010399003|10070799003|366016|10067099003|56012099006|11063799006|4143699003|22082099003|18002099003; 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Yeah I agree that supporting a generalised zero sized alloc is in some ways conceptually nicer, but I also can't see any good reason why you would want to do it, it sounds like a bug. That's also why in the latest version I made IdPool also not allow a zero capacity [1] (incidentally required to not have to change the grow code to avoid trying to double a zero capacity thing every time). Tbh, I feel that NonZero (and Alignment) is hard to use currently because of these ergonomics issues. But I reckon they're useful, so I like the idea of trying to making them easier to use. Maybe you can make an argument to not use NonZero here, but what about all the other times we will want to use it? [1]: https://lore.kernel.org/all/20260817-chid-v7-6-a5872e64d8f4@nvidia.com= /