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X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?qUWGwC/u7FfwVuY92sdEwtSpf0ZY1Z2qL3uFY4dVm2kfrDhSa08sRHbDmcwI?= =?us-ascii?Q?LLgs10CdhwI33YDGgCauYd9AUONdV/M9FufzWWl8/bX6B8ztArrjXH6I/O8o?= =?us-ascii?Q?0q3tUGmrf8FodA/VVFnfp+17ui1U+1tp5+W3QfFZRNDUi5rykFtcKR11N0W0?= =?us-ascii?Q?TbW7kGN7IF7Dfsl4kuq0wjFwGQPt4IWRIpF2gPIOvjg3wJapiXejV5yqGwDH?= =?us-ascii?Q?iviUCQPrLKxz4I0u18j7U5d/q0C+BhwY8C+fxcGArUoMv1Y/WE1lO5rUr++A?= =?us-ascii?Q?O7YpMcvqyPIhvDFEpKU2IcuJipzAnfvuSdeZVq93OdaqJdiOfXA/HXfze90V?= =?us-ascii?Q?7/p5+huq5mg9dMSO/m65YrG6PK3RxsmJAM0Rhwxc96XuL75fU/Xxbo2JYxYx?= =?us-ascii?Q?iE2h45QoXItuzU0KZdcR3rNyro3MlTlMbmtjh7GORrblyFJm0UDfBjXMBPe8?= =?us-ascii?Q?lkBE+B/YVwJazEWIIWfDENlfRfxxABMljT3bUdZl+oLjXRdfZZPD9AqhCqho?= =?us-ascii?Q?UfgPwzY+M2V0zdW594GXXjLbQP3qlrlJFdPPH2jRagG3ui+bAUx68HRXolgO?= =?us-ascii?Q?X9ZjYJGPzn8zPfLA410mnCyPzgw1SMRsjPaoOrN7WTQcN68WO0ZB4GHgAgi5?= =?us-ascii?Q?OjwBKDyciMIEFd2YBSRJ/4d00j1QV3ezOr8eEMX3X+t0O2bEE4pNrFT37pf8?= =?us-ascii?Q?h+6vMnsgLAnh3wrVQdLv+bx7vJv9ULsP1XmpqLIuFxSqh0ebzvB7m/SoV6wp?= =?us-ascii?Q?u4Qa3hsUPscElnz5urWa838gOKF1nYXGKslURH80A1Bo18XXw5NoBcbQaJlw?= =?us-ascii?Q?aCtvF9efgedBufL3mqa/QE9nIntUC4otGYepDMMki5NIYxfcBJEmuPgR59zD?= =?us-ascii?Q?UALr4QbGzMk1RzCkqP+3xP22GMLXrnKFIkAvG3WqrlqVx5lsJ1ZDryNdyDYv?= =?us-ascii?Q?7JMGKMIl9kVJrKMSonQgw3o0YO5KHJv1pVC6t86dmoxWJA+SYkwmlur/UeyE?= =?us-ascii?Q?sHp8?= X-OriginatorOrg: windriver.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2555109f-9502-470c-e82e-08d89556c9dc X-MS-Exchange-CrossTenant-AuthSource: DM6PR11MB4545.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Nov 2020 17:38:46.1449 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 8ddb2873-a1ad-4a18-ae4e-4644631433be X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: fkQOWlx3EXoXYZ1RxROg0LLjDCv6DGN7fX0LG1gXB09oxdSoiBeSl1wJk55or/QwxVTHlKnEIw6HjheTx1e5xJPHT2sHp/y1qZmtdP0+MpQ= X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR11MB4514 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [Re: [PATCH 0/3] clear_warn_once: add timed interval resetting] On 29/11/2020 (Sun 19:08) Andi Kleen wrote: > On Thu, Nov 26, 2020 at 01:30:26AM -0500, Paul Gortmaker wrote: > > But you currently can't make use of clear_warn_once unless you've got > > debugfs enabled and mounted - which may not be desired by some people > > in some deployment situations. > > Seems awfully special purpose. The problem with debugfs is security, > or is it no convenient process that could do cron like functionality? My understanding is that it is a bit of both. As users of rt tasks, they won't be running anything like cron that could add to OS jitter on the (presumably minimal) rootfs - so they were looking for a clean engineered solution with near zero overhead, that they could easily deploy on all nodes after the rt tuning was 99% completed and node images had been bundled. Just to be sure everything was operating as they'd aimed to achieve. I thought a boot arg (and the internal timer) seemed like a good fit to that requirement. No kernel or rootfs rebuilding required. And I figured others might be in the same boat and could use it too. Paul. -- > > If it's the first, perhaps what they really need is a way to get > a partial debugfs? > > -Andi