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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?fVMB1ETkhMGDWTlP6Y3VE+E2gp4PhpehW13svxkQv1XQoihmPi9KrYWk08UU?= =?us-ascii?Q?LvFgub7FYokIhLHWifdUM33AtcXhY/FarxqG/ikt3/eKlPglIpQNC8hMSlzv?= =?us-ascii?Q?yq6NhxwRkvag8wOQSaV+y8filONwLAQ2NCjLbbw/csxlzd1WvMcOTh147uem?= =?us-ascii?Q?ZS73hX/ZtIfbms0vuui5zskEnM5IwDDaPfk5GPEIFj3EpWusgZ3tV7dWRP4v?= =?us-ascii?Q?h9O2LzAr2vo0gl0QmouoDoqzZaq9UAwW84BducW2vcavV4P94lmEIGszafJq?= =?us-ascii?Q?l3p0/Xdpn7LmQesh+8jBp0/Z7asSmpzP3DTdlWDg4VPYPNGxuC4R+09CexNM?= =?us-ascii?Q?dS+iazSw3iZGOgovuVGVFAjzLZKwS6cH5uL9Q7uHXLokOAkCIQacz/E+NR5n?= =?us-ascii?Q?UwdoYcVp+/ss6udy6RKLClLGuU7vTLQN1jUMFmWkXlw4J3qZuQlBl7wjdxHm?= =?us-ascii?Q?9SV7I9qHuXI4TBo0Z70jElBcxLl4Y60jux0MM5rd3z3IuI3E7Fo3adflIqLt?= =?us-ascii?Q?Nr1x0BvtgVu/0fWjpXHp/9NmB9Os3SyERk/RFD1fwDIE9tdoOGVkm2Di5ddR?= =?us-ascii?Q?EIAnfzwIJZz1U8bYlDy0UtKD1rdckij6YKpMdV150fdNIo4ZSArgZ4BApyXu?= =?us-ascii?Q?yWLAyoC6MaTsE2GYRuaEjWh3k5kU5RcMk3q0rsBQocAIyZfSctXs+MPHBMTy?= =?us-ascii?Q?a+sLAMEnM6aQcS5C7yE5NVFcNeZKk8aiFJz+nduV4ALT1vMHg32NtkQKlX3n?= =?us-ascii?Q?rWEcB41ix2Gf+ZzCfVhVWS/2lslx+gNlrRdAKl7MCN215ETM1Y2OkhTAQiAI?= =?us-ascii?Q?Qw0UilVc47amEvQnAddXKPFMtesXan/YKTe+mRZRo9er34oq2ZK9i/OxvAU1?= =?us-ascii?Q?fiQluYIEG9SlMShKopnM+OcWG4ulTS5IuqjC0tWxMM4/acAo5YLGPsyMhGEd?= =?us-ascii?Q?uUSScOruJHC7JDn1PBucdV94RriU/pCcRdvUVF3OGWmLJGqXuowfSb1DePD3?= =?us-ascii?Q?XWMAYeHrJdVZik/OBV8p8kkwXWU0xT/e4Z6+br5vjIOpvZcHxuFHcu1kbKYe?= =?us-ascii?Q?pt8EZ8Y0mT9MHPFF3O32HFdjbVPKV9UdI/lH2IU7Az84zYt5MMxqrl7fZMNB?= =?us-ascii?Q?gYO/g+XFfD2BEANk8kH8MtRb/bpSRi0CUtWgZk6c9ttUkoPCfpcNJRYCnSGe?= =?us-ascii?Q?LTT89tLEbelz27ORK6l3hVGOhIQF7fwFJy9goFcE7g5ZYFb0/oGkCW0f35P5?= =?us-ascii?Q?oYn2U8IsDaTW/yRo2SSIOCAeVeojR+k+mZMmAorN1cXuxAuMoMmQMFDapA+e?= =?us-ascii?Q?xjTeqOa4HGcO+5GYhDa/BwtyThPx6IpiSOxplLoNQ7G4dJ0nHxzzNyz0aI1r?= =?us-ascii?Q?ijyvuuRnyi29dihJYnJcnUZs9PRCSm7SLJdGWiDKFWeXaFOFMy/sCb5MPtn8?= =?us-ascii?Q?qrlqPiMw1r+FUVRwh2O/XvsQAM7k3vaO7FW/D24NrbcC3kk8ME3d7N23JLhZ?= =?us-ascii?Q?iFoFQQ15tiQ40c2xpzq50Ubw9zno4VABrdfDtUg/Yv5zoR9VZP7gd85/oD4T?= =?us-ascii?Q?Vuur+1Hf1UsLSZHgJfLL49HGQmykI/B57uA2CA5dPinq5mSIPacfqHLU8hUn?= =?us-ascii?Q?le0Ow555Tm9MeN2slG0m81h897DaArMpOHca1XQZ+Hv6D2p8S+qBdzujM/+H?= =?us-ascii?Q?WGV4rYi+CZzsJj6W085m5xW0X8PwTSufhVrcjrfcnpYxvkUsKtr7aXAReioD?= =?us-ascii?Q?gUjYE14CkA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 425b83d8-fb71-4044-90e4-08dedbebf0d7 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Jul 2026 05:52:33.9582 (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: 9oJdr+kYz11Cxbu1HbACWO8uesWCOfoG+etxM62FbOgVI6UIfqfysurPOOAnt0UhH3NOmjFm/9BzODFpk9Y1Zg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CHXPR12MB999222 On Mon, Jul 06, 2026 at 12:09:36PM -1000, Tejun Heo wrote: > Hello, Andrea. > > Sashiko's first point looks real to me. The fix covers infinite->finite, > but a finite slice landing on a nohz_full CPU after idle has the same > issue whenever the previous run wasn't infinite (finite->idle->finite): > the enqueue path already cleared TICK_DEP_BIT_SCHED against the idle > rq->curr, and set_next_task_scx() re-asserts only on a slice-type > transition, so with SCX_RQ_CAN_STOP_TICK unchanged the tick stays > stopped. > > set_next_task_scx() knows the incoming task, so it can assert directly > rather than keying off the transition, like sched_fair_update_stop_tick() > does for CFS. Moving the finite assertion out of the transition branch > should do it: > > if (p->scx.slice != SCX_SLICE_INF && tick_nohz_full_cpu(cpu_of(rq))) > tick_nohz_dep_set_cpu(cpu_of(rq), TICK_DEP_BIT_SCHED); > > Can you fold that in and add a finite->idle->finite selftest case for v2? Yep, I'm currently looking/fixing at the issues found by Sashiko. I'll send a v2 in a bit. Thanks, -Andrea