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-rw-r--r--kernel/sched/features.h40
1 files changed, 37 insertions, 3 deletions
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index 143f55df890b..3c12d9f93331 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -5,8 +5,24 @@
* sleep+wake cycles. EEVDF placement strategy #1, #2 if disabled.
*/
SCHED_FEAT(PLACE_LAG, true)
+/*
+ * Give new tasks half a slice to ease into the competition.
+ */
SCHED_FEAT(PLACE_DEADLINE_INITIAL, true)
+/*
+ * Preserve relative virtual deadline on 'migration'.
+ */
+SCHED_FEAT(PLACE_REL_DEADLINE, true)
+/*
+ * Inhibit (wakeup) preemption until the current task has either matched the
+ * 0-lag point or until is has exhausted it's slice.
+ */
SCHED_FEAT(RUN_TO_PARITY, true)
+/*
+ * Allow wakeup of tasks with a shorter slice to cancel RUN_TO_PARITY for
+ * current.
+ */
+SCHED_FEAT(PREEMPT_SHORT, true)
/*
* Prefer to schedule the task we woke last (assuming it failed
@@ -16,19 +32,39 @@ SCHED_FEAT(RUN_TO_PARITY, true)
SCHED_FEAT(NEXT_BUDDY, false)
/*
+ * Allow completely ignoring cfs_rq->next; which can be set from various
+ * places:
+ * - NEXT_BUDDY (wakeup preemption)
+ * - yield_to_task()
+ * - cgroup dequeue / pick
+ */
+SCHED_FEAT(PICK_BUDDY, true)
+
+/*
* Consider buddies to be cache hot, decreases the likeliness of a
* cache buddy being migrated away, increases cache locality.
*/
SCHED_FEAT(CACHE_HOT_BUDDY, true)
/*
+ * Delay dequeueing tasks until they get selected or woken.
+ *
+ * By delaying the dequeue for non-eligible tasks, they remain in the
+ * competition and can burn off their negative lag. When they get selected
+ * they'll have positive lag by definition.
+ *
+ * DELAY_ZERO clips the lag on dequeue (or wakeup) to 0.
+ */
+SCHED_FEAT(DELAY_DEQUEUE, true)
+SCHED_FEAT(DELAY_ZERO, true)
+
+/*
* Allow wakeup-time preemption of the current task:
*/
SCHED_FEAT(WAKEUP_PREEMPTION, true)
SCHED_FEAT(HRTICK, false)
SCHED_FEAT(HRTICK_DL, false)
-SCHED_FEAT(DOUBLE_TICK, false)
/*
* Decrement CPU capacity based on time not spent running tasks
@@ -85,5 +121,3 @@ SCHED_FEAT(WA_BIAS, true)
SCHED_FEAT(UTIL_EST, true)
SCHED_FEAT(LATENCY_WARN, false)
-
-SCHED_FEAT(HZ_BW, true)