Later commits will change CFS bandwidth control throttling from a per-cfs_rq basis to a per-task basis. This means special care needs to be taken around any transition a task can have into and out of a cfs_rq.
To ease reviewing, the transitions are patched with dummy-helpers that are implemented later on. Add a class->task_woken callback to handle tasks being woken into potentially throttled cfs_rq's. Conversely, a task flagged for throttle-at-kernel-exit may block and need to have its pending throttle removed if runtime was replenished by the time it got woken up. Signed-off-by: Valentin Schneider <[email protected]> --- kernel/sched/fair.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index b2242307677ca..0cec3e70f1277 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5776,6 +5776,17 @@ static void task_throttle_cancel_irq_work_fn(struct irq_work *work) /* Write me */ } +static void task_woken_fair(struct rq *rq, struct task_struct *p) +{ + if (!cfs_bandwidth_used()) + return; + + if (task_needs_throttling(p)) + task_throttle_setup(p); + else + task_throttle_cancel(p); +} + void init_cfs_throttle_work(struct task_struct *p) { /* Protect against double add, see throttle_cfs_rq() and throttle_cfs_rq_work() */ @@ -13288,6 +13299,10 @@ DEFINE_SCHED_CLASS(fair) = { .task_change_group = task_change_group_fair, #endif +#ifdef CONFIG_CFS_BANDWIDTH + .task_woken = task_woken_fair, +#endif + #ifdef CONFIG_SCHED_CORE .task_is_throttled = task_is_throttled_fair, #endif -- 2.43.0
