/* * 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)/* * Use arch dependent cpu capacity functions */SCHED_FEAT(ARCH_CAPACITY, 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, true)#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)#endifSCHED_FEAT(FORCE_SD_OVERLAP, false)SCHED_FEAT(RT_RUNTIME_SHARE, true)SCHED_FEAT(LB_MIN, false)/* * Apply the automatic NUMA scheduling policy. Enabled automatically * at runtime if running on a NUMA machine. Can be controlled via * numa_balancing= */#ifdef CONFIG_NUMA_BALANCING/* * NUMA will favor moving tasks towards nodes where a higher number of * hinting faults are recorded during active load balancing. It will * resist moving tasks towards nodes where a lower number of hinting * faults have been recorded. */SCHED_FEAT(NUMA, true)#endif
/*
* 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)
/*
* Use arch dependent cpu capacity functions
*/
SCHED_FEAT(ARCH_CAPACITY, 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, true)
#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)
/*
* Apply the automatic NUMA scheduling policy. Enabled automatically
* at runtime if running on a NUMA machine. Can be controlled via
* numa_balancing=
*/
#ifdef CONFIG_NUMA_BALANCING
/*
* NUMA will favor moving tasks towards nodes where a higher number of
* hinting faults are recorded during active load balancing. It will
* resist moving tasks towards nodes where a lower number of hinting
* faults have been recorded.
*/
SCHED_FEAT(NUMA, true)
#endif