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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?/AtQYa7M8ps/z6LtGn7pAc+pVBHSqavlsqEfd7NdictIuFA34j/gfYDf1ZrO?= =?us-ascii?Q?e2+iLkVWkx97hwxwwSULoPuht7u8BjqpWuQ58bjUphwTNTuMpD6++8fPIZDd?= =?us-ascii?Q?VmJKFdkqZLpOcfflIogp/aCHKyOcgeHIM0j23n7P2zq+qm08Fn+hLSyxa4mp?= =?us-ascii?Q?JUDSXvcLuQD0Y3R44RF/dgyzzvbWeEdZZcm24f9Jl9vhqhdaBwVr8HOFNPZH?= =?us-ascii?Q?Lunk6I1zCx+wjIyXOIFpBw+Nt4e2CMrLDmRoGwomE99u1pPxs7Kha9wNUZuT?= =?us-ascii?Q?zQ/AALN8W0cmB5oCQYfTkG3tqBd1bCaclxL5VXvLSZj+k0Gst0fv1bqmjGec?= =?us-ascii?Q?DdYGDuvrOOq5e6wpuCcF3QshnP5zIN3WToVdUpLVbuzBw+XTvcya5X1ftnu2?= =?us-ascii?Q?lCOvSzGrfMtwi/BiQm0LqrbNMJecgaprcWF7XIiaMd9ZeNXh8kVnIrNM9wMo?= =?us-ascii?Q?6mwFUtLcUpGYIc9rNznyBfZP0adZChHJXTcAoCBee+S5RDFuElLHBh0h82q3?= =?us-ascii?Q?3NK0Xfnu3hxBdz5613kgPQXRqSqMn6QrB5qJYC8wHIkRE0Qtik7srewv86sU?= =?us-ascii?Q?qJMCFhWTqL2yLsdFNwAIe2yeEKqgdd15iBIiXJb/WzvoCmEa+6q/Xo/Vvmux?= =?us-ascii?Q?xt2/l7hQRaF/iBHiIyF/n5mn3frisZI1vZd5qq9eaXKlb8RL3iO5URC46TWX?= =?us-ascii?Q?QuqQSD3xkU413QC2BUlKF1/yqoDbJU3UdJzcAciAkr+ei0v3niBv1Re3V8ci?= =?us-ascii?Q?4ipUc9jd17xmzJGHYP9gA2NwJJUz55VxBfZiQsSTSaE+rm+0hDRIgUNK790o?= =?us-ascii?Q?lQrrPpu06GzOrn9wuC2ocQBSjr0J6SJHTXX/zQRxn9ckMLAOInlVyk+AfwXI?= =?us-ascii?Q?f6nYsYKnFdOQPog49UeMB9cX1zTWoGLtcaOrKHkiQPx5Q4SXiiAIyzQe7GSo?= =?us-ascii?Q?cMrmgBo17V5CAQwptQT32yrd6yG3AmDnnOXmd+rgaZAln5APLdHO5XgnfInM?= =?us-ascii?Q?eHZDYAbb24lrlRI+SvQw5JmJJzU2d49D0cALxvVtq+wsKzYFVf+8zdnreY7K?= =?us-ascii?Q?ZlP8pHktPHw82BAf3wu20HG3sz2HIz1aAakcwrpJ6nb8/CY0+2YFPpbV/3eA?= =?us-ascii?Q?+7/yiu1V1k3ekWwGnW3DyN67fx9F65RSnDcaHGaNlxkafxJ3xtb+faVy7aYH?= =?us-ascii?Q?Ud5l/hsNJ1zkHemr3q0NLbTw3pzNhTnmNJMjlDTTJK5g0vfpWXuBd/rkRxTN?= =?us-ascii?Q?y2O24EesZCMS2FhZpnOmj2V6n6EfjXrABBHkAum2oNAjW+LKSwRtgBncUsME?= =?us-ascii?Q?wBuFkd4pOJ3pG/7+om981BiWXkhiWDsrwZt/9281SaNRPmVkbT/peqISlFCu?= =?us-ascii?Q?9FBkUApAZeVwC3x+R5DQv22biJEXPzPgJ4eIGUvVqT74DWWTUOyRHM15VUVN?= =?us-ascii?Q?2qRxngPKEmWn3ZTCSXc/EsUZANhIoNZnBvUPPCBPhPh0ygVM4Xk5coaoms+p?= =?us-ascii?Q?cwX1lmHQlRcVrVqjpKfOL3Wax7xfTn/2AA7m10PRmFTIhUqD4hh7YORZcRY2?= =?us-ascii?Q?j/uzmHBpqIZ3pAh1Og9/3buSmxu/bwq2i1Nxiond0SKV4c/O2JIW8cv3kWlR?= =?us-ascii?Q?667Xf9c6y9uLXe5AItI2GmDor4cyh36qo/Lwbt5xp5/qVocEgQlTK0x1p4MZ?= =?us-ascii?Q?4oZKv3BtcNObPzv3778pjrYRPcs4KCKBTZGmyUEfo+sDapOTPxXcChP6BF2u?= =?us-ascii?Q?5FOomnWWoA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 5df69acf-0fab-457f-2a2a-08df01e68496 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Aug 2026 13:49:29.0745 (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: /nCj/pvP2A7lvXVLQfisYfKmCB0lfCX4DCYCPtLvNz6g4EL0ChLfKuvOVFCv+e0pMjYGRhj3oZ4HT2kMyinDmA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6667 On Mon, Aug 24, 2026 at 09:21:16PM +0800, Tao Cui wrote: > From: Tao Cui > > The scheduler core communicates the initial cpu controller settings > to the BPF scheduler through ops.cgroup_init() and reports subsequent > changes through the corresponding ops.cgroup_set_*() callbacks. > Whether and how a knob takes effect is up to the loaded scheduler: > it may implement the corresponding callback partially or not at all, > so cpu.max, cpu.weight and friends can silently have no effect. > > Document this in the basics section of sched-ext.rst. > > Signed-off-by: Tao Cui Looks good to me now. Reviewed-by: Andrea Righi Thanks, -Andrea > --- > v3 -> v4: Rephrase per Andrea's suggestion: mention ops.cgroup_init() > for the initial values, ops.cgroup_set_*() only for subsequent > changes, and disambiguate per-task nice (ops.set_weight()) from > cpu.weight.nice. > > v3: https://lore.kernel.org/r/20260824091501.547649-1-cui.tao@linux.dev > > Documentation/scheduler/sched-ext.rst | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/Documentation/scheduler/sched-ext.rst b/Documentation/scheduler/sched-ext.rst > index 35b550671ca7..794ae80b3ba3 100644 > --- a/Documentation/scheduler/sched-ext.rst > +++ b/Documentation/scheduler/sched-ext.rst > @@ -242,6 +242,21 @@ optional. The following modified excerpt is from > .name = "simple", > }; > > +Scheduler-Dependent Knobs > +------------------------- > + > +The fair-class scheduler enforces CPU controller settings such as > +``cpu.max``, ``cpu.weight`` and ``cpu.idle``. For sched_ext tasks, the > +scheduler core communicates these settings to the BPF scheduler > +through ``ops.cgroup_init()`` and reports subsequent changes through > +the corresponding ``ops.cgroup_set_*()`` callbacks. Similarly, per-task > +nice changes are converted to weights and reported through > +``ops.set_weight()``. > + > +Each BPF scheduler is responsible for implementing the scheduling > +semantics of these settings and may choose to ignore them. Consult the > +loaded scheduler's documentation before relying on these controls. > + > Dispatch Queues > --------------- > > -- > 2.43.0 >