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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Using the avg_vruntime, do the right thing and preserve lag across
* sleep+wake cycles. EEVDF placement strategy #1, #2 if disabled.
*/
SCHED_FEAT(PLACE_LAG, true)
/*
* Give new tasks half a slice to ease into the competition.
*/
SCHED_FEAT(PLACE_DEADLINE_INITIAL, true)
/*
* Preserve relative virtual deadline on 'migration'.
*/
SCHED_FEAT(PLACE_REL_DEADLINE, true)
/*
* Inhibit (wakeup) preemption until the current task has either matched the
* 0-lag point or until is has exhausted it's slice.
*/
SCHED_FEAT(RUN_TO_PARITY, true)
/*
* Allow wakeup of tasks with a shorter slice to cancel RUN_TO_PARITY for
* current.
*/
SCHED_FEAT(PREEMPT_SHORT, true)
/*
* Prefer to schedule the task we woke last (assuming it failed
* wakeup-preemption), since its likely going to consume data we
* touched, increases cache locality.
*/
SCHED_FEAT(NEXT_BUDDY, false)
/*
* Allow completely ignoring cfs_rq->next; which can be set from various
* places:
* - NEXT_BUDDY (wakeup preemption)
* - yield_to_task()
* - cgroup dequeue / pick
*/
SCHED_FEAT(PICK_BUDDY, true)
/*
* Consider buddies to be cache hot, decreases the likeliness of a
* cache buddy being migrated away, increases cache locality.
*/
SCHED_FEAT(CACHE_HOT_BUDDY, true)
/*
* Delay dequeueing tasks until they get selected or woken.
*
* By delaying the dequeue for non-eligible tasks, they remain in the
* competition and can burn off their negative lag. When they get selected
* they'll have positive lag by definition.
*
* DELAY_ZERO clips the lag on dequeue (or wakeup) to 0.
*/
SCHED_FEAT(DELAY_DEQUEUE, true)
SCHED_FEAT(DELAY_ZERO, true)
/*
* Allow wakeup-time preemption of the current task:
*/
SCHED_FEAT(WAKEUP_PREEMPTION, true)
SCHED_FEAT(HRTICK, false)
SCHED_FEAT(HRTICK_DL, false)
/*
* Decrement CPU capacity based on time not spent running tasks
*/
SCHED_FEAT(NONTASK_CAPACITY, true)
#ifdef CONFIG_PREEMPT_RT
SCHED_FEAT(TTWU_QUEUE, false)
#else
/*
* Queue remote wakeups on the target CPU and process them
* using the scheduler IPI. Reduces rq->lock contention/bounces.
*/
SCHED_FEAT(TTWU_QUEUE, true)
#endif
/*
* When doing wakeups, attempt to limit superfluous scans of the LLC domain.
*/
SCHED_FEAT(SIS_UTIL, true)
/*
* Issue a WARN when we do multiple update_rq_clock() calls
* in a single rq->lock section. Default disabled because the
* annotations are not complete.
*/
SCHED_FEAT(WARN_DOUBLE_CLOCK, false)
#ifdef HAVE_RT_PUSH_IPI
/*
* In order to avoid a thundering herd attack of CPUs that are
* lowering their priorities at the same time, and there being
* a single CPU that has an RT task that can migrate and is waiting
* to run, where the other CPUs will try to take that CPUs
* rq lock and possibly create a large contention, sending an
* IPI to that CPU and let that CPU push the RT task to where
* it should go may be a better scenario.
*/
SCHED_FEAT(RT_PUSH_IPI, true)
#endif
SCHED_FEAT(RT_RUNTIME_SHARE, false)
SCHED_FEAT(LB_MIN, false)
SCHED_FEAT(ATTACH_AGE_LOAD, true)
SCHED_FEAT(WA_IDLE, true)
SCHED_FEAT(WA_WEIGHT, true)
SCHED_FEAT(WA_BIAS, true)
/*
* UtilEstimation. Use estimated CPU utilization.
*/
SCHED_FEAT(UTIL_EST, true)
SCHED_FEAT(LATENCY_WARN, false)
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