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/*
* Only give sleepers 50% of their service deficit. This allows
* them to run sooner, but does not allow tons of sleepers to
* rip the spread apart.
*/
SCHED_FEAT(GENTLE_FAIR_SLEEPERS, true)
/*
* Place new tasks ahead so that they do not starve already running
* tasks
*/
SCHED_FEAT(START_DEBIT, 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)
/*
* Prefer to schedule the task that ran last (when we did
* wake-preempt) as that likely will touch the same data, increases
* cache locality.
*/
SCHED_FEAT(LAST_BUDDY, true)
/*
* Consider buddies to be cache hot, decreases the likelyness of a
* cache buddy being migrated away, increases cache locality.
*/
SCHED_FEAT(CACHE_HOT_BUDDY, true)
/*
* Allow wakeup-time preemption of the current task:
*/
SCHED_FEAT(WAKEUP_PREEMPTION, true)
SCHED_FEAT(HRTICK, false)
SCHED_FEAT(DOUBLE_TICK, false)
SCHED_FEAT(LB_BIAS, true)
/*
* Decrement CPU capacity based on time not spent running tasks
*/
SCHED_FEAT(NONTASK_CAPACITY, true)
/*
* Queue remote wakeups on the target CPU and process them
* using the scheduler IPI. Reduces rq->lock contention/bounces.
*/
SCHED_FEAT(TTWU_QUEUE, 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(FORCE_SD_OVERLAP, false)
SCHED_FEAT(RT_RUNTIME_SHARE, true)
SCHED_FEAT(LB_MIN, false)
SCHED_FEAT(ATTACH_AGE_LOAD, true)
/*
* Energy aware scheduling. Use platform energy model to guide scheduling
* decisions optimizing for energy efficiency.
*/
#ifdef CONFIG_DEFAULT_USE_ENERGY_AWARE
SCHED_FEAT(ENERGY_AWARE, true)
#else
SCHED_FEAT(ENERGY_AWARE, false)
#endif
/*
* Minimum capacity capping. Keep track of minimum capacity factor when
* minimum frequency available to a policy is modified.
* If enabled, this can be used to inform the scheduler about capacity
* restrictions.
*/
SCHED_FEAT(MIN_CAPACITY_CAPPING, true)
/*
* Enforce the priority of candidates selected by find_best_target()
* ON: If the target CPU saves any energy, use that.
* OFF: Use whichever of target or backup saves most.
*/
SCHED_FEAT(FBT_STRICT_ORDER, true)
/*
* Apply schedtune boost hold to tasks of all sched classes.
* If enabled, schedtune will hold the boost applied to a CPU
* for 50ms regardless of task activation - if the task is
* still running 50ms later, the boost hold expires and schedtune
* boost will expire immediately the task stops.
* If disabled, this behaviour will only apply to tasks of the
* RT class.
*/
SCHED_FEAT(SCHEDTUNE_BOOST_HOLD_ALL, false)
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