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Shenoy" References: <20240710090210.41856-1-kprateek.nayak@amd.com> <20240710090210.41856-4-kprateek.nayak@amd.com> <20240710150557.GB27299@noisy.programming.kicks-ass.net> From: K Prateek Nayak In-Reply-To: <20240710150557.GB27299@noisy.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SATLEXMB03.amd.com (10.181.40.144) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BN1PEPF00004683:EE_|PH0PR12MB7011:EE_ X-MS-Office365-Filtering-Correlation-Id: 5841cbda-8c8d-4e64-fc4e-08dca10cfabb X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|36860700013|1800799024|82310400026|7416014; X-Microsoft-Antispam-Message-Info: =?utf-8?B?STRaZzZFczJFdG0veFVDSzhacEZIQWVvOHVoOHF1NmlXV1FJWkxhTDgrTUVK?= =?utf-8?B?VXova0d4b01leWVjNWdObTVsemdLdi8vU0RVRnJ5cFV2VjIyRlBtZUM0aXAx?= =?utf-8?B?aElMSWJrMURTcmtZNjBRd0c5aW5zdS9oYzVjdXA5QkJWTWF3aVVoMTh5aGt1?= =?utf-8?B?aG5EUWZpYTJEbE8vV2tzUUFxejladm11YnFZM0ViN0xNTW95clV3NWdGMU5N?= =?utf-8?B?aGJMRDdvanpZSEpwR3doZ2Q1b2tkRjZvMENDMURiWVJ5QlR4TUoybjBsUDEx?= =?utf-8?B?ejhZd0VFaHd6b0laSkxjQlJ1U2lCMHgrekkyd0xob0RPOHBkSTlwV3lWUHAy?= =?utf-8?B?ZVdEdVlkaUd6djlwMFlJR2oyRjBuWlliWUMzWHZJUzE1cWJxK2N3dFZYQWNr?= =?utf-8?B?T1NzcUcwbVhmeFN5UGNZVEpJdnVGZklNT2RhcThHVEZHOC9mREd3MnE3aWpk?= =?utf-8?B?R2ZaVGloU0ZHbnRRWWcwNVkxdDlYKzBEbzUyM0doQ1psS2h4bE1iV3UvWEVF?= =?utf-8?B?YUhPYUYwekgya002VHoyblQ0M3cyMkU3UkFzR2JqRFBYbzhBOFRSU09ndzNt?= =?utf-8?B?WVVOT29pQTJSVlZvTFJmZFNhL2tEd3VvUmE4b2JZWEJLSVA2VjM5eGxCYkRU?= =?utf-8?B?S0ZENkZiRW1ycHVTN2k4YlFRL3VkWGlJTTZOcVhpNzdjaGc4WmFaM1kvTWlO?= =?utf-8?B?d25FNGFVNFM3bU00UFp6WEtFSWZKSERPWitpWndENzhCR2h3L21FWVdhZnlB?= =?utf-8?B?L3E1UkszZWdwVlZJMkpUQ2VXMU13dEUvdVBvQXI4a0FmT0JoM2F4Z3A4VFZw?= =?utf-8?B?RmJxUGdmODhMSlphaSs5QTFsRVJyOGM1NFY5K2Y3VzBvWFFyYzIxenMrdjVN?= =?utf-8?B?OUVOb1U5akN1Z3o0dGFQbFdIcjU3OG1PdjdzYkFsWG1DcEJ0UTNzbC9lM0d1?= =?utf-8?B?OTNMbWNHQmx6TlZxMU9YaWoybk5yL1lIL1NBMmdTcHQ4NnZhd0F0SWR2NnVa?= =?utf-8?B?RE9iSHlHZTFDUlhSU1NXMU5BdXBNcm5CUThZQmRnbE0yUW1KaE1XTUxQSHJ5?= =?utf-8?B?VllVRXBWcldLKzU1R3BCaXdHcUQxK3paY1YvMVFvQU51YnpvaUVNM2EyenVy?= =?utf-8?B?ZHBoOTdSWWk1ZzM0RFdqZUVkTDJpT2tmdlNpMXF2VlVmdERJVll5UDhpS3pl?= =?utf-8?B?enltcEJvZ25OOXNONGFOWTF0YmN2VHpIL21qUzFYVFVGQjNPL0EvUWlaNVBx?= =?utf-8?B?UEkzMDk3dkZxTzgvRkFUUy9YbjlRUW0rOVFBL2NJb1FvS0dyRDRCRlVMWHVq?= =?utf-8?B?S1lXaUxiME5xTnlsVWRTK2x6b3hoTmtEZVFzUWpBdHVaa2tsby9ZYnVyT2Fq?= =?utf-8?B?S1o5MmJFTU02YnhSL0FnZzBIaHl0VUZqWks4WENETmVjak9KNHVVTGFCRG5S?= =?utf-8?B?b2IrQVlpTDZreDVtMUNhSGoxU1lSU1dieUcyR3U4M3o2cCs4MVFXTTZOcm01?= =?utf-8?B?Ri9pMmNraFBjUXpWMEtzMmxRdTQ2YWZnUUl5RXB0bTdiSC9EMmN1V3lzR00v?= =?utf-8?B?WVZYMHcrV1daK2ZYYkdLR0FON0VGano0MU5FNnpXR2YrK0htZWk3a2JCNEVz?= =?utf-8?B?c3NLRkNJektSd01FM2hyR29Gb3QxODdCUm40MjFoVTVoV2lFWWR2cURZM29I?= =?utf-8?B?eDgzSjNlU2I4VFRjMk9DQmwyemhyYThIRHB1ZEtla0VFT1FSYmpLRnk4eDBJ?= =?utf-8?B?VXJSWkRkVzRSTlZwd2dRTHUrZmo1RVR0S3o2UWZlaitDQmFJUWNHMGs0ZEtm?= =?utf-8?B?RFdQcmhMcklpVE81V2diQmJtelRHS3Y5SkVoNVNrMHJua2JDNHA4WFR3dkJZ?= =?utf-8?B?OWhvWDY1OHB5OHFOU1VXMld2N0dORGRJeVJhY0FpUXVQcGRrM1lud1Uvc2dj?= =?utf-8?Q?Q3JGy1uaLTaf2IPKf3OcTPujypWcoRyW?= X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:SATLEXMB04.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(376014)(36860700013)(1800799024)(82310400026)(7416014);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Jul 2024 18:20:29.5727 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 5841cbda-8c8d-4e64-fc4e-08dca10cfabb X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BN1PEPF00004683.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB7011 Hello Peter, Thank you for the feedback. On 7/10/2024 8:35 PM, Peter Zijlstra wrote: > On Wed, Jul 10, 2024 at 09:02:10AM +0000, K Prateek Nayak wrote: > >> [..snip..] > > On first reading I wonder why you've not re-used and hooked into the > PREEMPT_RT variant of should_wake_ksoftirqd(). That already has a per > CPU variable to do exactly this. With this RFC, I intended to check if everyone was onboard with the idea and of the use-case. One caveat with re-using the existing "softirq_ctrl.cnt" hook that PREEMPT_RT uses is that we'll need to expose the functions that increment and decrement it, for it to be used in kernel/smp.c. I'll make those changes in v2 and we can see if there are sufficient WARN_ON() to catch any incorrect usage in !PREEMPT_RT case. -- Thanks and Regards, Prateek