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-rw-r--r--kernel/sched/features.h91
1 files changed, 91 insertions, 0 deletions
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+
+/*
+ * Using the avg_vruntime, do the right thing and preserve lag across
+ * sleep+wake cycles. EEVDF placement strategy #1, #2 if disabled.
+ */
+SCHED_FEAT(PLACE_LAG, true)
+SCHED_FEAT(PLACE_DEADLINE_INITIAL, true)
+SCHED_FEAT(RUN_TO_PARITY, true)
+
+/*
+ * Prefer to schedule the task we woke last (assuming it failed
+ * wakeup-preemption), since its likely going to consume data we
+ * touched, increases cache locality.
+ */
+SCHED_FEAT(NEXT_BUDDY, false)
+
+/*
+ * 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)
+
+/*
+ * 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
+ */
+SCHED_FEAT(NONTASK_CAPACITY, true)
+
+#ifdef CONFIG_PREEMPT_RT
+SCHED_FEAT(TTWU_QUEUE, false)
+#else
+
+/*
+ * Queue remote wakeups on the target CPU and process them
+ * using the scheduler IPI. Reduces rq->lock contention/bounces.
+ */
+SCHED_FEAT(TTWU_QUEUE, true)
+#endif
+
+/*
+ * When doing wakeups, attempt to limit superfluous scans of the LLC domain.
+ */
+SCHED_FEAT(SIS_PROP, false)
+SCHED_FEAT(SIS_UTIL, true)
+
+/*
+ * Issue a WARN when we do multiple update_rq_clock() calls
+ * in a single rq->lock section. Default disabled because the
+ * annotations are not complete.
+ */
+SCHED_FEAT(WARN_DOUBLE_CLOCK, false)
+
+#ifdef HAVE_RT_PUSH_IPI
+/*
+ * In order to avoid a thundering herd attack of CPUs that are
+ * lowering their priorities at the same time, and there being
+ * a single CPU that has an RT task that can migrate and is waiting
+ * to run, where the other CPUs will try to take that CPUs
+ * rq lock and possibly create a large contention, sending an
+ * IPI to that CPU and let that CPU push the RT task to where
+ * it should go may be a better scenario.
+ */
+SCHED_FEAT(RT_PUSH_IPI, true)
+#endif
+
+SCHED_FEAT(RT_RUNTIME_SHARE, false)
+SCHED_FEAT(LB_MIN, false)
+SCHED_FEAT(ATTACH_AGE_LOAD, true)
+
+SCHED_FEAT(WA_IDLE, true)
+SCHED_FEAT(WA_WEIGHT, true)
+SCHED_FEAT(WA_BIAS, true)
+
+/*
+ * UtilEstimation. Use estimated CPU utilization.
+ */
+SCHED_FEAT(UTIL_EST, true)
+SCHED_FEAT(UTIL_EST_FASTUP, true)
+
+SCHED_FEAT(LATENCY_WARN, false)
+
+SCHED_FEAT(HZ_BW, true)