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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?gg/FNhP2ejcE/P3JljFiQEcK6JBPksayRL8SV7OSupgGA3zPxjrDZ4g71GVz?= =?us-ascii?Q?wayOPc3f76av6YmYEMJXzz9JydnBoryNn/JkQW2XG8jU2MoUmeo5AYRx6LFj?= =?us-ascii?Q?sfg6zGmbvZOf6HD9Xsm7hRzV7CCQCFtWwJqPH/SeDW8aT8Lb7hK1ObZMepid?= =?us-ascii?Q?F0IjLO1YE7k5JFylGc3y9NBOP2Wx6MHMPE4YyFzi/NOMKwmPsUHw3//jcJe0?= =?us-ascii?Q?d0fyUVTEepFvA7WnDD8ycYqGRDi0ZWGSehZQfrThcHLEQlv4gNMuMv6Ph9Kd?= =?us-ascii?Q?q3ZolmDhMGLICXHk77pX3/3y2+7KnjlIrikWGSWhKukBsWe064sZMCY2uGpl?= =?us-ascii?Q?lYy+aKMl80YsnBn53KP/IjLRDXnhVLbfScMhKEnXOi23p8ooWrX0Z9lgjZs1?= =?us-ascii?Q?sPJ5jpjglQIkhCyvBdWhsNLs0R6DQlbB96ChJWZCx9TuSIiLsdplyFPGeZJH?= =?us-ascii?Q?/U7PlmvLsXk1Gv6Svtv3BowAMLJbUJQP8E0p9cf2niXkmCtMNwIzTq6RyZhx?= =?us-ascii?Q?FpxmHnB1/4nMuWBDe6iI8swkAcV5VkuZeIgNGsoyJ8i28THQ6h3cY61Hcwhw?= =?us-ascii?Q?TtFoBsWiGwlim3M0iGXAMkR4fkalHNC3RUU4fX+wI1zyiKrwgWvIH7VPgbZr?= =?us-ascii?Q?blDZ5gj6e/dHZE07VwcywQ9w9PKFbMfkHSQvmYu/LVbuvWgDxzJYL+pPLTMs?= =?us-ascii?Q?pgz1oXgsBDjOMDSqmBgfO7VpuwET/bQkOrsb2khujv1Jcmd79FZ5eg6Ixpva?= =?us-ascii?Q?TNH0OMsAzv0kesdduD4ChrKYD9v3n6cGi7rkJDbFtA3juvuowFDn4sSf5jup?= =?us-ascii?Q?AN62hcLu8xtdMGIoDyK24K3RkLiZjECo2ny4FF4fTo8qvrNlQ+81G+iJ2kez?= =?us-ascii?Q?K/8aZWtWuzyoY9Y9l8tOBD3F3A3uVx1DX082rUAz6ziiQZ6BCytITmDJEBuo?= =?us-ascii?Q?u1qyKunRdvGPEHjbub9Nobp0tNC4qraV/+TMe9Jhyxm2xbxYuCUCNseu5lGj?= =?us-ascii?Q?xfNgXLfccPQyhsn13rNSjs2wohtQPlkXu/SwY/zb1QyjGD4qqkx9ZBEI+vvB?= =?us-ascii?Q?vMcf4lFapM6MYTh436nUPwp3N8NKpn3mIQATmjoreMFrhD8tgnOaFfZr69jm?= =?us-ascii?Q?3cCtOHxkDDtt+Y9Wndq0RZifRsvj27dFB72si1JBPk2bMPmNdTJIp6qU6HXe?= =?us-ascii?Q?QTIBJXoCoB1PKM0y3EKVCPtzuNFRdzFrLGm2gCOK2Eo3t2Sz2sfYltK5WNAu?= =?us-ascii?Q?tq1hMlEJO80Tram/hpn4DUzqMLlb1a1Z5xiICb2cYxEmnOZPOC29aB+ssyip?= =?us-ascii?Q?jShM5DW2AHdQBDFSz8kHJKgupMN2eVcs9HS8jUpwasThm68nwMLJzpp5uqcD?= =?us-ascii?Q?mD8u5xPCqs21d/5THgB8+169etatxSTCJYhZDsCdQbzHmGTJE0VF75lQ0xKP?= =?us-ascii?Q?WIY711Jl343eNm9dPe6c5yuNpUXnfUA2wZNHAAFLj4Xg0vnAMro6RmeIvaq+?= =?us-ascii?Q?5aqnL78DOZDL7/wvTqNod0/MYdZ4rWkQU+GYhTvnsMVdynT0sNd8Nd+mGJiw?= =?us-ascii?Q?X6SIXTMyuleN7biRHEA/OfXJNrZF6JWSAsVRiPGSyS4YC/zFKrABlxQbSEeo?= =?us-ascii?Q?eifRwymGMjwYJWCASRKgk3km7nHue4HT9rNHsRphgiN7pDC+LqjZJTHEge83?= =?us-ascii?Q?18zCtNT3lJgR075J3azM+zZV4H6OZNkvPvPhreaMiEQaf4ZJeFIUcVs+5bQz?= =?us-ascii?Q?spa2aaSJJA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7b4c26ff-5996-4b8e-2a74-08df2cf8c969 X-MS-Exchange-CrossTenant-AuthSource: BL1PR12MB5174.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Oct 2026 09:18:35.3400 (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: XT0CitCv2QpSA6bTN9w3JWTv5mmAxbkOGNdTllE9lUccioDwU2qEPBwClSmBQ9vgXBEeLZm48aDhWkFgThT+xA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV3PR12MB9353 On Sat, Oct 17, 2026 at 10:16:00PM -1000, Tejun Heo wrote: > Hello, Andrea. > > On Sun, Oct 18, 2026 at 09:01:18AM +0200, Andrea Righi wrote: > > With a root-only scheduler the walk skips the root and queues nothing, but > > resched_sync_ecaps() still runs on every online CPU, starting the ext_server and > > queueing the resched irq work for no reason. Can we do it only if something was > > actually queued? > ... > > ame on the offline side: with no sub-sched nr is 0, but we still do > > update_rq_clock(), dl_server_start(&rq->ext_server) and the irq work on a CPU > > that's going down and the ext_server stays enqueued there until > > sched_cpu_dying() stops it. How about: > > These are on the cpu hotplug path, which is really cold, and the cost is a > resched on one cpu. It's minuscule and doesn't matter, so I don't think it > makes sense to add any complexity to avoid it. Right, fair enough. -Andrea