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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KUQftL7uIpHfkXSDJbqsS3AfK5ZGqu7j8GG9tYZaUnebY+hT6tl/Y/t/bR7g?= =?us-ascii?Q?dINdego9RV0/nNM0ugHj10ObCLi83KyQQ3f9d6FwRyzg5T03n3WHbaGVYNlJ?= =?us-ascii?Q?D4ObhgbLVb1Vt3xm8tqzIgYlWIlV7UgOAt/aKC+/OvqA6GJghjZ4lKrg3ams?= =?us-ascii?Q?QliAPvX8xHJrog93vSrWtiemF7085P+EuErbVgEcGEtowpUbMBq9qbXUuZdl?= =?us-ascii?Q?mQbf/WJZ6ZQOnG1szzXO3pJEMHWPOgSmj7dYdoaycOpOJ+rOaoYiHuBHLjkD?= =?us-ascii?Q?kZJXQA5B7xa5GKaG8tMsw5DMBoc948s5oV4OZd4zh+F1olQazLANjkVuf39e?= =?us-ascii?Q?TFsGZHLurBofkQgXffOGDBJKo6jZEhACyRxAao6/cH/BkRDzWn0615vWQEoQ?= =?us-ascii?Q?QtaMWBapoc4W3mgeFCyFwYCA0BZV1/S/8lcBMIyFpeRNZmtexv6YH21LW0Ji?= =?us-ascii?Q?iIFBFUdzBRD3qqE+9ZKM7pAuGcbD9aUiYQi3nk4tMoWNQbgE5LR8/bMh8kbF?= =?us-ascii?Q?wv6Y0JIAW9KW/ywk/qhVZzKZMrzjr8K+8grEBxyR+4iXYcJXHIfTX+5S/OF5?= =?us-ascii?Q?oEE0ujx8TKV8OWfoFpDckJAjXQl4pvixRYFnzdQvdea+Yceh+TcnWW1O/GBM?= =?us-ascii?Q?Uo9V1HXN+l9NZXBLfy+ffEW/91z8ZekvUvHVvoOF7f6wKsT1ovywJqldEHAS?= =?us-ascii?Q?DpwsewKKvCzeOPAPepU7XsMSYzBPOto2l0Lf7WFvsY+5YbNvCRKZ6MevPQ+2?= =?us-ascii?Q?YbIvmor8k5hK0AiAjsjlhQAJvN+XQbZdh7bIlw+jz+UrB7tPTQ7NDy6GDhfP?= =?us-ascii?Q?SKIjcaSaj6vzF+Re71tStownnir7dJiMFH9BMSx/rQHrAXnQgeGM1evQCAtN?= =?us-ascii?Q?pxfU5V/RFhRqwiBd3E3mbsKgPOvZjXbpSxhSrr1PrSQYC/tjCRgCD3dC1y3D?= =?us-ascii?Q?SPO8XxSS/Fqsdi7SmDBWn7XR9/ZYAaKAUyRrUDG/jRtjXmtxCxZ/UssCRj3L?= =?us-ascii?Q?r8T4UotK2SMpyQ2rI5RBD9970p5BAue12fafm+J7U+p0hFTl21pAs4SoO1Gb?= =?us-ascii?Q?dsJkzPX3zMjaF9DT15jLlqFODIhKw8ujA03hv+d0UwJtnJwcWzEezWZhk9fC?= =?us-ascii?Q?Lvmh3Uvr3q1q5yA1dcvO1zm2G0PTTppHTxSwGTt2jWGufYcO3hTnfO2A1UPv?= =?us-ascii?Q?uIwbHXsIYWgDb6VN9u5Lr5qSZpXoV85uGrIQB9EJLnhmv0DIPOeRtODDytZj?= =?us-ascii?Q?3i3XsZbHYpGQxfIotyo+EpR8NZctePopDINRy3DzrPCFAIJ97YnKXcBFMmlV?= =?us-ascii?Q?FjOCuj8HgmdQlVp8PNc0CfychNLHusfqQAqT8BDVdDB+Yq3jQ/lelKaQnGEq?= =?us-ascii?Q?VFmyTjO6M7IIEuH/OERIpz0ZFYSAykQrTs2ze+7BQZhUCNoYLF5kNIkk6iZc?= =?us-ascii?Q?uEkR8+JXjy4H81x1qmKPS0pM3PEx807V2QA4ITIY/pX2cJPf7OS4iF655PTx?= =?us-ascii?Q?3g6Ql5DQivDrcFh6IlIzjVi0nYFeNKxiHIR8QYRE+4ew5Gia2q3syo/QxKiI?= =?us-ascii?Q?7LYrUkipKEjXFheJ1gVu6VUCdqSmFdPxCPMDB17N2K6o7a07883XCVa64GFo?= =?us-ascii?Q?mx2dfQpiAsM5JKQ2bvL1C5ng5ilalljIsKjRcfvIdaujzOKnETSPJ2duMmKf?= =?us-ascii?Q?001vb9DRXXo9ouaZF1tTDC0lTkrFHegO9ItOkvJ4GvyloPwyC1Ry1Hr0Depj?= =?us-ascii?Q?gvF1TuUFRg=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2814ea95-c76d-42c1-a263-08df01f15e07 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB4827.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Aug 2026 15:07:08.7712 (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: vEvgmL0O7/4CZraNs/6WB5Lu7HlQlfTSaDIWh2++itwej5typVfGvB4qB0s+noaHK7ocjVnlTJig/jfe7G0aKg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PPFD4454CAA9 Hi Tao, On Mon, Aug 24, 2026 at 10:28:16PM +0800, Tao Cui wrote: > From: Tao Cui > > scx_cgroup_init_args carries the initial weight and bandwidth control > parameters of a cgroup to ops.cgroup_init(), but not its cpu.idle > state. A cgroup that was already configured idle before the scheduler > was loaded (or before it was onlined under it) is presented as > non-idle, and the BPF scheduler only learns about it if cpu.idle is > written again later. > > Add the idle state to scx_cgroup_init_args and fill it in all four > places that build the args: scx_tg_online() for cgroups onlined under > the scheduler, scx_cgroup_init() for cgroups that already exist when > the scheduler is loaded, and the sub-scheduler handover paths > scx_cgroup_claim_subtree() and scx_cgroup_return_subtree(). > > Verified in a VM with a probe scheduler printing the init args: a > cgroup configured cpu.idle=1 before loading shows idle=1 in > ops.cgroup_init(), the default shows 0, and later cpu.idle writes > still come through ops.cgroup_set_idle(). The sub-scheduler paths > are compile-tested only. > > Signed-off-by: Tao Cui We should probably add: Fixes: 347ed2d566da ("sched/ext: Implement cgroup_set_idle() callback" With that: Reviewed-by: Andrea Righi Thanks, -Andrea > --- > v1 -> v2: Also fill .idle in the sub-scheduler handover paths in > sub.c, scx_cgroup_claim_subtree() and scx_cgroup_return_subtree(), > missed in v1 and pointed out by Andrea Righi and the sashiko AI > review bot. > > v1: https://lore.kernel.org/r/20260824133954.561956-1-cui.tao@linux.dev > > kernel/sched/ext/ext.c | 4 +++- > kernel/sched/ext/internal.h | 3 +++ > kernel/sched/ext/sub.c | 2 ++ > 3 files changed, 8 insertions(+), 1 deletion(-) > > diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c > index b646711a45fe..a7218314dcfb 100644 > --- a/kernel/sched/ext/ext.c > +++ b/kernel/sched/ext/ext.c > @@ -4764,7 +4764,8 @@ int scx_tg_online(struct task_group *tg) > { .weight = tg->scx.weight, > .bw_period_us = tg->scx.bw_period_us, > .bw_quota_us = tg->scx.bw_quota_us, > - .bw_burst_us = tg->scx.bw_burst_us }; > + .bw_burst_us = tg->scx.bw_burst_us, > + .idle = tg->scx.idle }; > > ret = SCX_CALL_OP_RET(sch, cgroup_init, > NULL, tg->css.cgroup, &args); > @@ -5185,6 +5186,7 @@ static int scx_cgroup_init(struct scx_sched *sch) > .bw_period_us = tg->scx.bw_period_us, > .bw_quota_us = tg->scx.bw_quota_us, > .bw_burst_us = tg->scx.bw_burst_us, > + .idle = tg->scx.idle, > }; > > ret = SCX_CALL_OP_RET(sch, cgroup_init, NULL, css->cgroup, &args); > diff --git a/kernel/sched/ext/internal.h b/kernel/sched/ext/internal.h > index 53e136a47924..aa149a9c29f7 100644 > --- a/kernel/sched/ext/internal.h > +++ b/kernel/sched/ext/internal.h > @@ -259,6 +259,9 @@ struct scx_cgroup_init_args { > u64 bw_period_us; > u64 bw_quota_us; > u64 bw_burst_us; > + > + /* whether the cgroup is configured idle via cpu.idle */ > + bool idle; > }; > > enum scx_cpu_preempt_reason { > diff --git a/kernel/sched/ext/sub.c b/kernel/sched/ext/sub.c > index 0554448835bd..9701bd1d8ea0 100644 > --- a/kernel/sched/ext/sub.c > +++ b/kernel/sched/ext/sub.c > @@ -1361,6 +1361,7 @@ static s32 scx_cgroup_claim_subtree(struct scx_sched *sch) > .bw_period_us = tg->scx.bw_period_us, > .bw_quota_us = tg->scx.bw_quota_us, > .bw_burst_us = tg->scx.bw_burst_us, > + .idle = tg->scx.idle, > }; > > if (tg->scx.sched != parent || > @@ -1464,6 +1465,7 @@ static void scx_cgroup_return_subtree(struct scx_sched *sch) > .bw_period_us = tg->scx.bw_period_us, > .bw_quota_us = tg->scx.bw_quota_us, > .bw_burst_us = tg->scx.bw_burst_us, > + .idle = tg->scx.idle, > }; > > /* the first pass must have transferred everything */ > -- > 2.43.0 >