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/*
* Disregards a certain amount of sleep time (sched_latency_ns) and
* considers the task to be running during that period. This gives it
* a service deficit on wakeup, allowing it to run sooner.
*/
SCHED_FEAT(FAIR_SLEEPERS, 1)
/*
* 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, 1)
/*
* By not normalizing the sleep time, heavy tasks get an effective
* longer period, and lighter task an effective shorter period they
* are considered running.
*/
SCHED_FEAT(NORMALIZED_SLEEPER, 0)
/*
* Place new tasks ahead so that they do not starve already running
* tasks
*/
SCHED_FEAT(START_DEBIT, 1)
/*
* Should wakeups try to preempt running tasks.
*/
SCHED_FEAT(WAKEUP_PREEMPT, 1)
/*
* Compute wakeup_gran based on task behaviour, clipped to
* [0, sched_wakeup_gran_ns]
*/
SCHED_FEAT(ADAPTIVE_GRAN, 1)
/*
* When converting the wakeup granularity to virtual time, do it such
* that heavier tasks preempting a lighter task have an edge.
*/
SCHED_FEAT(ASYM_GRAN, 1)
/*
* Always wakeup-preempt SYNC wakeups, see SYNC_WAKEUPS.
*/
SCHED_FEAT(WAKEUP_SYNC, 0)
/*
* Wakeup preempt based on task behaviour. Tasks that do not overlap
* don't get preempted.
*/
SCHED_FEAT(WAKEUP_OVERLAP, 0)
/*
* Use the SYNC wakeup hint, pipes and the likes use this to indicate
* the remote end is likely to consume the data we just wrote, and
* therefore has cache benefit from being placed on the same cpu, see
* also AFFINE_WAKEUPS.
*/
SCHED_FEAT(SYNC_WAKEUPS, 1)
/*
* Based on load and program behaviour, see if it makes sense to place
* a newly woken task on the same cpu as the task that woke it --
* improve cache locality. Typically used with SYNC wakeups as
* generated by pipes and the like, see also SYNC_WAKEUPS.
*/
SCHED_FEAT(AFFINE_WAKEUPS, 1)
/*
* Weaken SYNC hint based on overlap
*/
SCHED_FEAT(SYNC_LESS, 1)
/*
* Add SYNC hint based on overlap
*/
SCHED_FEAT(SYNC_MORE, 0)
/*
* 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, 0)
/*
* 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, 1)
/*
* Consider buddies to be cache hot, decreases the likelyness of a
* cache buddy being migrated away, increases cache locality.
*/
SCHED_FEAT(CACHE_HOT_BUDDY, 1)
/*
* Use arch dependent cpu power functions
*/
SCHED_FEAT(ARCH_POWER, 0)
SCHED_FEAT(HRTICK, 0)
SCHED_FEAT(DOUBLE_TICK, 0)
SCHED_FEAT(LB_BIAS, 1)
SCHED_FEAT(LB_WAKEUP_UPDATE, 1)
SCHED_FEAT(ASYM_EFF_LOAD, 1)
/*
* Spin-wait on mutex acquisition when the mutex owner is running on
* another cpu -- assumes that when the owner is running, it will soon
* release the lock. Decreases scheduling overhead.
*/
SCHED_FEAT(OWNER_SPIN, 1)
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