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 likelyness 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(DOUBLE_TICK, false)
42
43/*
44 * Decrement CPU capacity based on time not spent running tasks
45 */
46SCHED_FEAT(NONTASK_CAPACITY, true)
47
48/*
49 * Queue remote wakeups on the target CPU and process them
50 * using the scheduler IPI. Reduces rq->lock contention/bounces.
51 */
52SCHED_FEAT(TTWU_QUEUE, true)
53
54/*
55 * When doing wakeups, attempt to limit superfluous scans of the LLC domain.
56 */
57SCHED_FEAT(SIS_AVG_CPU, false)
58SCHED_FEAT(SIS_PROP, true)
59
60/*
61 * Issue a WARN when we do multiple update_rq_clock() calls
62 * in a single rq->lock section. Default disabled because the
63 * annotations are not complete.
64 */
65SCHED_FEAT(WARN_DOUBLE_CLOCK, false)
66
67#ifdef HAVE_RT_PUSH_IPI
68/*
69 * In order to avoid a thundering herd attack of CPUs that are
70 * lowering their priorities at the same time, and there being
71 * a single CPU that has an RT task that can migrate and is waiting
72 * to run, where the other CPUs will try to take that CPUs
73 * rq lock and possibly create a large contention, sending an
74 * IPI to that CPU and let that CPU push the RT task to where
75 * it should go may be a better scenario.
76 */
77SCHED_FEAT(RT_PUSH_IPI, true)
78#endif
79
80SCHED_FEAT(RT_RUNTIME_SHARE, true)
81SCHED_FEAT(LB_MIN, false)
82SCHED_FEAT(ATTACH_AGE_LOAD, true)
83
84SCHED_FEAT(WA_IDLE, true)
85SCHED_FEAT(WA_WEIGHT, true)
86SCHED_FEAT(WA_BIAS, true)
87
88/*
89 * UtilEstimation. Use estimated CPU utilization.
90 */
91SCHED_FEAT(UTIL_EST, true)

 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 likelyness 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(DOUBLE_TICK, false)
42
43/*
44 * Decrement CPU capacity based on time not spent running tasks
45 */
46SCHED_FEAT(NONTASK_CAPACITY, true)
47
48/*
49 * Queue remote wakeups on the target CPU and process them
50 * using the scheduler IPI. Reduces rq->lock contention/bounces.
51 */
52SCHED_FEAT(TTWU_QUEUE, true)
53
54/*
55 * When doing wakeups, attempt to limit superfluous scans of the LLC domain.
56 */
57SCHED_FEAT(SIS_AVG_CPU, false)
58SCHED_FEAT(SIS_PROP, true)
59
60/*
61 * Issue a WARN when we do multiple update_rq_clock() calls
62 * in a single rq->lock section. Default disabled because the
63 * annotations are not complete.
64 */
65SCHED_FEAT(WARN_DOUBLE_CLOCK, false)
66
67#ifdef HAVE_RT_PUSH_IPI
68/*
69 * In order to avoid a thundering herd attack of CPUs that are
70 * lowering their priorities at the same time, and there being
71 * a single CPU that has an RT task that can migrate and is waiting
72 * to run, where the other CPUs will try to take that CPUs
73 * rq lock and possibly create a large contention, sending an
74 * IPI to that CPU and let that CPU push the RT task to where
75 * it should go may be a better scenario.
76 */
77SCHED_FEAT(RT_PUSH_IPI, true)
78#endif
79
80SCHED_FEAT(RT_RUNTIME_SHARE, true)
81SCHED_FEAT(LB_MIN, false)
82SCHED_FEAT(ATTACH_AGE_LOAD, true)
83
84SCHED_FEAT(WA_IDLE, true)
85SCHED_FEAT(WA_WEIGHT, true)
86SCHED_FEAT(WA_BIAS, true)
87
88/*
89 * UtilEstimation. Use estimated CPU utilization.
90 */
91SCHED_FEAT(UTIL_EST, true)
92SCHED_FEAT(UTIL_EST_FASTUP, true)