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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?v9pPvGlw/9dH7CdQ1cJnbNiJoGJDxcCSmkA/7De3+r+8NpLjUFbv961WO5SG?= =?us-ascii?Q?G4ENrT5F+Spy10vKPtCaL8nZ0qJu0AaKj2sAQMPVO7jy/aEjF8O+3v92dXqw?= =?us-ascii?Q?3wNladq+ihuH3DjrCRqfuaBBBkZIDVWvbOGm4c/+gBpjgcU/HUcG3pD40iWy?= =?us-ascii?Q?tS6QKM1Q2pI4fJdWCnIE26mxNwKCuhWey8WYP9gtys0QCzS3zPwQmlQTtQPK?= =?us-ascii?Q?QrZEYsERRBV0Xl2SDkW00q5/7ayqM/LQKBddAg2kPopL+e1sYzJ2RTSFqp0q?= =?us-ascii?Q?Ju/EGNVme94jqnEPNjGiM1DXyievAbkULekLmKhAqykyN7cQUmRBZ0XV6uwC?= =?us-ascii?Q?m18UJ52SstnNHBlBmxZ4pTSKygDy4DynvTGB5CuC+27jmNF9ILOqI/vSbiDC?= =?us-ascii?Q?kZNbCp8rloOGM/f3YdOSrd2B9wMBMyScpzX9S0dPnuZ03YvU2NFPdCSSvzfn?= =?us-ascii?Q?grp7gZpnpiLfBrUwKI4zYkVRq5Nn23kMgWHprnjEDr0a64EnRHAIpoYBipac?= =?us-ascii?Q?+vhoCcCurzOfVBInQJy96mNMcFbTuukwLwoUX3tp9jHd3QmqVp9QsFgE8yo0?= =?us-ascii?Q?HANWz8RwS8QMij3TWQ7AuxzBzjzoOU5cz6T3lGCmrR9Rcv8axPvlTI52YAiH?= =?us-ascii?Q?7Zt6ua8/3tQ8a/Xd2OdaPwXuVcpplbUky0cTmqEslpOmBWRUSdgamw4Y/BJ7?= =?us-ascii?Q?mwYpf9Y9yUQQyoCiJ27TIMLSrZJwKaBGSyRI2DMn+fnwpQwaAX34Lt/pUcaV?= =?us-ascii?Q?hWGk1ksAABeLkWNNE60IPFR+zUvLU0oWpVqEbUl4nPH1NBuuA3+aGe3H4LLf?= =?us-ascii?Q?EhspPKoV+8bNEjC/73wrQC/mGet6NbwqiUl6BIdID+7ruKQQLM57fVUqkOcD?= =?us-ascii?Q?JXCFSW28dZH+XQHlcRk1IhoSG1Ln9WClSLqNx/euTzwVnBeh/wcN7RXsKBlF?= =?us-ascii?Q?WvSlJZGuKg/A2Bv+ARZQjQd0BhVHSUjYGXKYLL0YWHm8yrmM6aWSz6jPkcNW?= =?us-ascii?Q?SPzmqlLzWvLH+bSmShbpUWEetBeq5hiDbwACthhSaXe/JoyApfBSalYq+8dZ?= =?us-ascii?Q?91pxM5QJQpoY7cmY14fSY4xVoka/tMxAcvme1+axuY1WMcsPUt/UNlv01+aE?= =?us-ascii?Q?iag0wi6s9Zzp0hHAC7EpIbE05eksSm47Bs+OgdUk5K2Js3Zr+blJJSlarMf5?= =?us-ascii?Q?dhp1S5MsMU3scaGoGi5nvpZRVSegW/MouYQFbxXA/piOlALNEAL9oWNBbSaA?= =?us-ascii?Q?3PNOZv7F4dOSAsQLaNcknioWmXwObf5qFNZ2ibnipjnPLayssAPBy9LVUvu5?= =?us-ascii?Q?V+GpVmS5d1bQ1TA9PZXMnDdE0VHlxoX9rQfetX3NupLOWB+Vd3xmFta7Acne?= =?us-ascii?Q?r6hSeFtuSNyUx385tfBnLKVJjco6ZCrqGP163VI6vdftPZyAUTeiev9OVTsI?= =?us-ascii?Q?u2Dt/9XdLDAk54nPEyhjMY+T1hK5Zs/denc2VT4EqdTk6ke7B0ePgasHWsxJ?= =?us-ascii?Q?N/aUEf9B1SWadoSx5tHdrR4qESClN7v+KkiyG6S+Hy1OMSu+J4DRuSnC3qZv?= =?us-ascii?Q?sVLeevUZtYswRWe4edBmBcIAM3zH0ogtHaKSOBC0wLbPCtbk95iTSDD57Ifk?= =?us-ascii?Q?m5bhGdEJrH5tl5TzQtu7koDOvSdY3TPQm+dIWRwnU+QYzYjUrkDk16NDBCz+?= =?us-ascii?Q?gjAyC64yNaDvFalO6nnGJ2euPb5sd/o8sr9Z6e2Q1/saQo7d2Jth9lD1pXoz?= =?us-ascii?Q?EDYrz2H0WQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6801d1ac-bf6f-454d-f236-08df1e0579f2 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Sep 2026 08:41:38.1159 (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: 0oe+0JTBM8HTPgQynfVX/MT2VRJG2OB1w+3jWsmgpz4WZPFNwgWpet4dq9khZwIN52LVPBrzqrrVs6vv/8S5uQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB7816 Hierarchical BPF schedulers need to know how many CPUs a cgroup can run on when distributing group-wide weights. For example, fair's group share calculation scales a group's weight by the smaller of its estimated runnable task count and the number of CPUs in its effective cpuset (tg_cpus() -> cpuset_num_cpus()). Without that count, a BPF scheduler can only use the machine-wide CPU count and may give a group confined to a few CPUs excessive shares. This patchset adds scx_bpf_cgroup_nr_cpus(), a kfunc that returns the same count fair uses. This allows scx_eevdf to implement proper group scheduling, computing per-cgroup shares the same way fair does, including for groups confined to a subset of CPUs through cpuset. Andrea Righi (3): cgroup/cpuset: Protect is_in_v2_mode() in cpuset_num_cpus() sched_ext: Introduce scx_bpf_cgroup_nr_cpus() selftests/sched_ext: Test scx_bpf_cgroup_nr_cpus() kernel/cgroup/cpuset.c | 6 +- kernel/sched/ext/ext.c | 22 ++ tools/sched_ext/include/scx/common.bpf.h | 1 + tools/sched_ext/include/scx/compat.bpf.h | 7 + tools/testing/selftests/sched_ext/Makefile | 6 +- .../selftests/sched_ext/cgroup_nr_cpus.bpf.c | 60 +++ tools/testing/selftests/sched_ext/cgroup_nr_cpus.c | 419 +++++++++++++++++++++ tools/testing/selftests/sched_ext/config | 1 + 8 files changed, 519 insertions(+), 3 deletions(-) create mode 100644 tools/testing/selftests/sched_ext/cgroup_nr_cpus.bpf.c create mode 100644 tools/testing/selftests/sched_ext/cgroup_nr_cpus.c