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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?hhvE0dNOzpVGnZeV7xzVtZWEJT9qO68nkpHDcQfNuRfk/V4ub0A6M1R7n7Vg?= =?us-ascii?Q?o3yhZt1qyAgjXemA+UUjxZH1wXSAoy0C7NsV3ZdRHitG0MQb+rp+kJ5k8OV3?= =?us-ascii?Q?5sto7P3n7Io3CN6Y+pZdzkZ4apVBMdSyPaGAfFbkt+pq5WOLxg+/jXVt5j4g?= =?us-ascii?Q?AdJA0OgVTSgA0wb5JQt8tOKNujeiwHRegNaK0uLti8XT5Wod430aEQizyA+A?= =?us-ascii?Q?B331obl4Vqbstde32Ez02GGQf6/bRfUsdL2I+qj5PPARrix5mI8OoenaYWF2?= =?us-ascii?Q?cDe620k57sn0dWC6fO+qiRfVtxsZZ2WaWVR9L/n11UUZa6CojdruyhRX0EJi?= =?us-ascii?Q?cm1mrZY8IC0JwA/2cqbzg91u1a174OsNcHO9kjbkaHlcxeusXSTgl4D6exGJ?= =?us-ascii?Q?cgdVUjD7e+WE/pTb+9pP1drEx85fpBazkxRnsD9anVy46MoaBfTGU1qNDRFC?= =?us-ascii?Q?wY3nV9l09e5qTFgGz+5X8bWbUmayUzO5gMaU7BEU4YKc2JboCHepwLs/AsBf?= =?us-ascii?Q?teqXNy2YoACT0mypuV2lHa22YtHkuLvaxoM0w7Q4v5l5ZuzAiwX7Hu5RkrjE?= =?us-ascii?Q?TxCi3LF3zdfVAjy1Q40rudv08VZHMPw2snDZjh5HIkSjZ4f3Q1ass2sWkyDy?= =?us-ascii?Q?YluBuGFHvme7a/N7YOwimwIWl603TkrRnVHCTs0i0FDFQPPeU+lLF7mCgYBV?= =?us-ascii?Q?heDLZnnfU9L1p0txYJFPvn9dentKbWkAcHPRESGiCuhMJWFQI/gX2DShqQMr?= =?us-ascii?Q?ic8KE/wBS7+lksvN6KRazufmLtzZqjZ0FHqRqV4t9v/gLcQ0ImxqXO8SuuZs?= =?us-ascii?Q?G4tOx9372+fH2jR9YrxkHRquyPP+wsBm2KWA0O2eXRjrLFKpdlmRJAutVDMT?= =?us-ascii?Q?E8Vyn7zkcuIxSKtHpeSlkmZYkSk2xSLNLC+xwwfz1G1wcSUr9iOcTHDZHAkw?= =?us-ascii?Q?7kJzFqHN+CkANd0W+mYeJ8sxmxVfOt07aTXXeoBlavP7Wzw1Ma2bSwHaiu8n?= =?us-ascii?Q?YensieFXMyzxlvFznSK7TNmt4T2wSmHEhTlj8eYXmLBFACYUkF8q6K+sSnJo?= =?us-ascii?Q?QWYEjNMEQDkKUGaSxNcyEdvtfKOmT2140m8vbX+zufsNNvpzrow7IYt2W3O9?= =?us-ascii?Q?C1GVwhSMYQu1fj9I8ESzuf/ahf946a22v3jw7C0YVcFVUU/gT/km7n59jSHO?= =?us-ascii?Q?lxneX9aN60oC0JpXUvjeiqdrqKVRfTzjHQp1mDlsiGfLHMurIoC2lhIKQ16F?= =?us-ascii?Q?GflM0t3IY10i/zeuRCweYXoTaOlUoPyAtqYIgBweSmF0e9o7gMdo0M2Sqd1D?= =?us-ascii?Q?n/RSU+tdIOD52f0DqQLZrhBprwjbSzkb/BgSXpx9M2EWLNqKPNxGLTT6dbil?= =?us-ascii?Q?RLWGjgGN7sWocZmjS6BHqCdmOJDQrCiur/UUcZykFKQwwk0DUZAQojl6tJwY?= =?us-ascii?Q?pQUcq9+KN8hNbhtrKZE+C+B9eBtRr5XDfVXAdzFR6evEHougaPCv/k9tU04k?= =?us-ascii?Q?2nwGJfEhdBVO/qpRePxR2PtSv3YzXii48sH8pV1ma5Pq7gDJrlY8j7644FGo?= =?us-ascii?Q?Ko2u5sdbG3FvT/CgijArz7VWMY+a8mcOH9am3qrwQofUvgxjJwyeeddYOFnj?= =?us-ascii?Q?2N3Di40lrBqmdwMOhpAmCvEGtQTYdzTdmFU9oUP9poCf90kRDBrErnZBl+xy?= =?us-ascii?Q?aJ92QH5vZ+MHu8fp60rASyXBXyaHpj60etkKakptAyVYC3m7b7gKZ3foDutj?= =?us-ascii?Q?0yJF/q+Jcg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5a7a68a6-2d8c-488e-9955-08def19fbc88 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Aug 2026 20:42:30.2337 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: E6c0Pl0v3NIQmAsX3URsmjVCJTGwaHaHEEOGjD5PeCefkj6yf0pgYxtPuyDbTkVSHkfR+zXMHB19RXJg3weexw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB5820 Hi Tejun, On Sun, Aug 02, 2026 at 11:54:35AM -1000, Tejun Heo wrote: > Hello, > > v2: Changes from the sashiko AI review: > > - Declare scx_sched_all outside the CONFIG_EXT_SUB_SCHED block, the > definition is unconditional (0002). > > - Track the overload grace and usage-decay timestamps in jiffies_64 so > that 32-bit arithmetic on them can't wrap (0009). > > - Drop the now-unread always_enq_immed rodata mirror (0011). > > v1: https://lore.kernel.org/r/20260801085150.2697653-1-tj@kernel.org > > A sub-scheduler holds only the cids its parent granted and nothing > guarantees that they cover its tasks' affinities. A task that can run on > none of them currently has no good ending: the scheduler's insert is > cap-rejected and reenqueued until the repeat limit ejects the scheduler, or > the task stalls into the watchdog. > > This series adds kernel-side rescue execution. A scheduler marks an insert > that may be cap-rejected with SCX_ENQ_RESCUE and the kernel, instead of > bouncing it, runs the task on the target cpu at a small configured > bandwidth. A rescue starts out non-disruptive. Schedulers that hold caps on > the cid largely stay in control of the cpu - a preemption cap, for example, > still lets its holder preempt the rescuee. When a rescue goes unserved for > too long, it escalates into protected execution. > > When a cpu's rescue queue stays oversaturated past the overload threshold, > the kernel ejects the sub-scheduler with the highest recent rescue > consumption on that cpu instead of misblaming the waiter's owner. With the updated patch 08/12 everything looks good to me. For the whole series: Reviewed-by: Andrea Righi Thanks, -Andrea