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