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Tue, 25 Aug 2026 11:17:57 +0000 Message-ID: Date: Tue, 25 Aug 2026 19:17:47 +0800 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 7/9] fs/resctrl: Do not invoke smp_processor_id() in preemptible context To: Reinette Chatre CC: , , , , , , , , , , References: Content-Language: en-US From: "Chen, Yu C" In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SI2PR02CA0013.apcprd02.prod.outlook.com (2603:1096:4:194::21) To DM4PR11MB6020.namprd11.prod.outlook.com (2603:10b6:8:61::19) 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: DM4PR11MB6020:EE_|CH3PR11MB8590:EE_ X-MS-Office365-Filtering-Correlation-Id: 874b44fc-ef3b-4d71-f69b-08df029a83fb X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|23010399003|376014|7416014|366016|1800799024|10067099003|11063799006|4143699003|56012099006|6133799003|18002099003|22082099003; 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This changelog > describes context that does not exist (yet) and then presents the change in > this patch as a bugfix. This is not accurate and misrepresents this change. > OK, let me remove above description which has not yet been introduced. >> >> __l3_mon_event_count() calls smp_processor_id() to find the CPU to read >> from. For an any_cpu event that lookup is unsafe: >> the code runs in preemptible task context, so smp_processor_id() emits a >> debug warning. >> >> Skip the current-CPU lookup when an event's any_cpu flag is set, events with >> this flag do not require execution on a specific CPU. For legacy MSR-based >> access, update rmid_read::err if the reading of the event was dispatched to >> a wrong CPU, according to the change at: >> https://lore.kernel.org/lkml/6b3c66a49788828bd8c04a6911bd74c91ccd56f3.1782857711.git.reinette.chatre@intel.com/ > > This has been merged now so it should not be necessary to call this out, > at least in this format > OK, I'll adjust the description to avoid mentioning the above change. thanks, Chenyu