/* * 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_SHARES_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)