1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Only give sleepers 50% of their service deficit. This allows
  4 * them to run sooner, but does not allow tons of sleepers to
  5 * rip the spread apart.
  6 */
  7SCHED_FEAT(GENTLE_FAIR_SLEEPERS, true)
  8
  9/*
 10 * Place new tasks ahead so that they do not starve already running
 11 * tasks
 12 */
 13SCHED_FEAT(START_DEBIT, true)
 14
 15/*
 
 
 
 
 
 
 
 
 16 * Prefer to schedule the task we woke last (assuming it failed
 17 * wakeup-preemption), since its likely going to consume data we
 18 * touched, increases cache locality.
 19 */
 20SCHED_FEAT(NEXT_BUDDY, false)
 21
 22/*
 23 * Prefer to schedule the task that ran last (when we did
 24 * wake-preempt) as that likely will touch the same data, increases
 25 * cache locality.
 26 */
 27SCHED_FEAT(LAST_BUDDY, true)
 28
 29/*
 30 * Consider buddies to be cache hot, decreases the likeliness of a
 31 * cache buddy being migrated away, increases cache locality.
 32 */
 33SCHED_FEAT(CACHE_HOT_BUDDY, true)
 34
 35/*
 36 * Allow wakeup-time preemption of the current task:
 37 */
 38SCHED_FEAT(WAKEUP_PREEMPTION, true)
 39
 40SCHED_FEAT(HRTICK, false)
 41SCHED_FEAT(HRTICK_DL, false)
 42SCHED_FEAT(DOUBLE_TICK, false)
 
 43
 44/*
 45 * Decrement CPU capacity based on time not spent running tasks
 
 
 46 */
 47SCHED_FEAT(NONTASK_CAPACITY, true)
 48
 49#ifdef CONFIG_PREEMPT_RT
 50SCHED_FEAT(TTWU_QUEUE, false)
 51#else
 
 52
 53/*
 54 * Queue remote wakeups on the target CPU and process them
 55 * using the scheduler IPI. Reduces rq->lock contention/bounces.
 56 */
 57SCHED_FEAT(TTWU_QUEUE, true)
 58#endif
 59
 60/*
 61 * When doing wakeups, attempt to limit superfluous scans of the LLC domain.
 62 */
 63SCHED_FEAT(SIS_PROP, false)
 64SCHED_FEAT(SIS_UTIL, true)
 65
 66/*
 67 * Issue a WARN when we do multiple update_rq_clock() calls
 68 * in a single rq->lock section. Default disabled because the
 69 * annotations are not complete.
 70 */
 71SCHED_FEAT(WARN_DOUBLE_CLOCK, false)
 72
 73#ifdef HAVE_RT_PUSH_IPI
 74/*
 75 * In order to avoid a thundering herd attack of CPUs that are
 76 * lowering their priorities at the same time, and there being
 77 * a single CPU that has an RT task that can migrate and is waiting
 78 * to run, where the other CPUs will try to take that CPUs
 79 * rq lock and possibly create a large contention, sending an
 80 * IPI to that CPU and let that CPU push the RT task to where
 81 * it should go may be a better scenario.
 82 */
 83SCHED_FEAT(RT_PUSH_IPI, true)
 84#endif
 85
 86SCHED_FEAT(RT_RUNTIME_SHARE, false)
 87SCHED_FEAT(LB_MIN, false)
 88SCHED_FEAT(ATTACH_AGE_LOAD, true)
 89
 90SCHED_FEAT(WA_IDLE, true)
 91SCHED_FEAT(WA_WEIGHT, true)
 92SCHED_FEAT(WA_BIAS, true)
 93
 94/*
 95 * UtilEstimation. Use estimated CPU utilization.
 96 */
 97SCHED_FEAT(UTIL_EST, true)
 98SCHED_FEAT(UTIL_EST_FASTUP, true)
 99
100SCHED_FEAT(LATENCY_WARN, false)
101
102SCHED_FEAT(ALT_PERIOD, true)
103SCHED_FEAT(BASE_SLICE, true)

 
 1/*
 2 * Only give sleepers 50% of their service deficit. This allows
 3 * them to run sooner, but does not allow tons of sleepers to
 4 * rip the spread apart.
 5 */
 6SCHED_FEAT(GENTLE_FAIR_SLEEPERS, true)
 7
 8/*
 9 * Place new tasks ahead so that they do not starve already running
10 * tasks
11 */
12SCHED_FEAT(START_DEBIT, true)
13
14/*
15 * Based on load and program behaviour, see if it makes sense to place
16 * a newly woken task on the same cpu as the task that woke it --
17 * improve cache locality. Typically used with SYNC wakeups as
18 * generated by pipes and the like, see also SYNC_WAKEUPS.
19 */
20SCHED_FEAT(AFFINE_WAKEUPS, true)
21
22/*
23 * Prefer to schedule the task we woke last (assuming it failed
24 * wakeup-preemption), since its likely going to consume data we
25 * touched, increases cache locality.
26 */
27SCHED_FEAT(NEXT_BUDDY, false)
28
29/*
30 * Prefer to schedule the task that ran last (when we did
31 * wake-preempt) as that likely will touch the same data, increases
32 * cache locality.
33 */
34SCHED_FEAT(LAST_BUDDY, true)
35
36/*
37 * Consider buddies to be cache hot, decreases the likelyness of a
38 * cache buddy being migrated away, increases cache locality.
39 */
40SCHED_FEAT(CACHE_HOT_BUDDY, true)
41
42/*
43 * Use arch dependent cpu power functions
44 */
45SCHED_FEAT(ARCH_POWER, false)
46
47SCHED_FEAT(HRTICK, false)
 
48SCHED_FEAT(DOUBLE_TICK, false)
49SCHED_FEAT(LB_BIAS, true)
50
51/*
52 * Spin-wait on mutex acquisition when the mutex owner is running on
53 * another cpu -- assumes that when the owner is running, it will soon
54 * release the lock. Decreases scheduling overhead.
55 */
56SCHED_FEAT(OWNER_SPIN, true)
57
58/*
59 * Decrement CPU power based on time not spent running tasks
60 */
61SCHED_FEAT(NONTASK_POWER, true)
62
63/*
64 * Queue remote wakeups on the target CPU and process them
65 * using the scheduler IPI. Reduces rq->lock contention/bounces.
66 */
67SCHED_FEAT(TTWU_QUEUE, true)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
68
69SCHED_FEAT(FORCE_SD_OVERLAP, false)
70SCHED_FEAT(RT_RUNTIME_SHARE, true)
 
 
 
 
 
 
 
 
 
 
 
 
71SCHED_FEAT(LB_MIN, false)