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Fri, 30 May 2025 02:29:44 +0000 Message-ID: <2e62c38c-cd2e-4aa6-af43-2b8e77c09b78@intel.com> Date: Thu, 29 May 2025 19:29:42 -0700 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 01/43] sched: Clean up and standardize #if/#else/#endif markers in sched/autogroup.[ch] To: Ingo Molnar CC: Dietmar Eggemann , Linus Torvalds , Peter Zijlstra , Shrikanth Hegde , Thomas Gleixner , Valentin Schneider , "Steven Rostedt" , Mel Gorman , Vincent Guittot , Sebastian Andrzej Siewior , Juri Lelli , "LKML Mailing List" References: <20250528080924.2273858-1-mingo@kernel.org> <20250528080924.2273858-2-mingo@kernel.org> Content-Language: en-US From: Sohil Mehta In-Reply-To: <20250528080924.2273858-2-mingo@kernel.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SJ0PR03CA0198.namprd03.prod.outlook.com (2603:10b6:a03:2ef::23) To BYAPR11MB3320.namprd11.prod.outlook.com (2603:10b6:a03:18::25) 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: BYAPR11MB3320:EE_|PH3PPF957B3B2A8:EE_ X-MS-Office365-Filtering-Correlation-Id: 8fb76d12-487f-4f6c-c5e8-08dd9f21d66b X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|7416014; 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Any documentation link? The comment next to the #else could relate to ending of the previous section or related to beginning of the next section. I see 3 formats commonly used: 1) #else /* CONFIG_FOO */ $ grep -Pr '^(?=.*#else)(?=.*\/\*)(?=.*CONFIG_)(?!.*!)(?!.*:).*$' . Count: 1122 2) #else /* !CONFIG_FOO */ $ grep -Pr '^(?=.*#else)(?=.*\/\*)(?=.*CONFIG_)(?=.*!)(?!.*:).*$' . Count: 642 3) #else /* !CONFIG_FOO: */ $ grep -Pr '^(?=.*#else)(?=.*\/\*)(?=.*CONFIG_)(?=.*!)(?=.*:).*$' Count: 43 Even though the counts do not account for the #ifndef cases, they provide a rough approximation of the kernel usage. #1 and #2 already conflict with each other. I feel adding more to the 3rd type would probably make it more confusing for readers and developers. I am assuming that the ':' at the end is to signify that the comment pertains to the beginning of the following section. If we want to standardize #3 wouldn't it be better to first converge between #1 and #2? > ... > #endif /* !CONFIG_FOO */ >