| 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 | */ |
| 6 | SCHED_FEAT(GENTLE_FAIR_SLEEPERS, true) |
| 7 | |
| 8 | /* |
| 9 | * Place new tasks ahead so that they do not starve already running |
| 10 | * tasks |
| 11 | */ |
| 12 | SCHED_FEAT(START_DEBIT, true) |
| 13 | |
| 14 | /* |
| 15 | * Prefer to schedule the task we woke last (assuming it failed |
| 16 | * wakeup-preemption), since its likely going to consume data we |
| 17 | * touched, increases cache locality. |
| 18 | */ |
| 19 | SCHED_FEAT(NEXT_BUDDY, false) |
| 20 | |
| 21 | /* |
| 22 | * Prefer to schedule the task that ran last (when we did |
| 23 | * wake-preempt) as that likely will touch the same data, increases |
| 24 | * cache locality. |
| 25 | */ |
| 26 | SCHED_FEAT(LAST_BUDDY, true) |
| 27 | |
| 28 | /* |
| 29 | * Consider buddies to be cache hot, decreases the likelyness of a |
| 30 | * cache buddy being migrated away, increases cache locality. |
| 31 | */ |
| 32 | SCHED_FEAT(CACHE_HOT_BUDDY, true) |
| 33 | |
| 34 | /* |
| 35 | * Allow wakeup-time preemption of the current task: |
| 36 | */ |
| 37 | SCHED_FEAT(WAKEUP_PREEMPTION, true) |
| 38 | |
| 39 | /* |
| 40 | * Use arch dependent cpu capacity functions |
| 41 | */ |
| 42 | SCHED_FEAT(ARCH_CAPACITY, true) |
| 43 | |
| 44 | SCHED_FEAT(HRTICK, false) |
| 45 | SCHED_FEAT(DOUBLE_TICK, false) |
| 46 | SCHED_FEAT(LB_BIAS, true) |
| 47 | |
| 48 | /* |
| 49 | * Decrement CPU capacity based on time not spent running tasks |
| 50 | */ |
| 51 | SCHED_FEAT(NONTASK_CAPACITY, true) |
| 52 | |
| 53 | /* |
| 54 | * Queue remote wakeups on the target CPU and process them |
| 55 | * using the scheduler IPI. Reduces rq->lock contention/bounces. |
| 56 | */ |
| 57 | SCHED_FEAT(TTWU_QUEUE, true) |
| 58 | |
| 59 | SCHED_FEAT(FORCE_SD_OVERLAP, false) |
| 60 | SCHED_FEAT(RT_RUNTIME_SHARE, true) |
| 61 | SCHED_FEAT(LB_MIN, false) |
| 62 | |
| 63 | /* |
| 64 | * Apply the automatic NUMA scheduling policy. Enabled automatically |
| 65 | * at runtime if running on a NUMA machine. Can be controlled via |
| 66 | * numa_balancing= |
| 67 | */ |
| 68 | #ifdef CONFIG_NUMA_BALANCING |
| 69 | SCHED_FEAT(NUMA, false) |
| 70 | |
| 71 | /* |
| 72 | * NUMA_FAVOUR_HIGHER will favor moving tasks towards nodes where a |
| 73 | * higher number of hinting faults are recorded during active load |
| 74 | * balancing. |
| 75 | */ |
| 76 | SCHED_FEAT(NUMA_FAVOUR_HIGHER, true) |
| 77 | |
| 78 | /* |
| 79 | * NUMA_RESIST_LOWER will resist moving tasks towards nodes where a |
| 80 | * lower number of hinting faults have been recorded. As this has |
| 81 | * the potential to prevent a task ever migrating to a new node |
| 82 | * due to CPU overload it is disabled by default. |
| 83 | */ |
| 84 | SCHED_FEAT(NUMA_RESIST_LOWER, false) |
| 85 | #endif |