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authorMartin Schwidefsky <schwidefsky@de.ibm.com>2011-12-19 19:23:15 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2011-12-19 19:23:15 +0100
commit612ef28a045efadb3a98d4492ead7806a146485d (patch)
tree05621c87b37e91c27b06d450d76adffe97ce9666 /kernel/sched/features.h
parentc3e0ef9a298e028a82ada28101ccd5cf64d209ee (diff)
parent07cde2608a3b5c66515363f1b53623b1536b9785 (diff)
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Merge branch 'sched/core' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into cputime-tip
Conflicts: drivers/cpufreq/cpufreq_conservative.c drivers/cpufreq/cpufreq_ondemand.c drivers/macintosh/rack-meter.c fs/proc/stat.c fs/proc/uptime.c kernel/sched/core.c
Diffstat (limited to 'kernel/sched/features.h')
-rw-r--r--kernel/sched/features.h70
1 files changed, 70 insertions, 0 deletions
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
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+/*
+ * Only give sleepers 50% of their service deficit. This allows
+ * them to run sooner, but does not allow tons of sleepers to
+ * rip the spread apart.
+ */
+SCHED_FEAT(GENTLE_FAIR_SLEEPERS, true)
+
+/*
+ * Place new tasks ahead so that they do not starve already running
+ * tasks
+ */
+SCHED_FEAT(START_DEBIT, true)
+
+/*
+ * Based on load and program behaviour, see if it makes sense to place
+ * a newly woken task on the same cpu as the task that woke it --
+ * improve cache locality. Typically used with SYNC wakeups as
+ * generated by pipes and the like, see also SYNC_WAKEUPS.
+ */
+SCHED_FEAT(AFFINE_WAKEUPS, 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)
+
+/*
+ * Prefer to schedule the task that ran last (when we did
+ * wake-preempt) as that likely will touch the same data, increases
+ * cache locality.
+ */
+SCHED_FEAT(LAST_BUDDY, true)
+
+/*
+ * Consider buddies to be cache hot, decreases the likelyness of a
+ * cache buddy being migrated away, increases cache locality.
+ */
+SCHED_FEAT(CACHE_HOT_BUDDY, true)
+
+/*
+ * Use arch dependent cpu power functions
+ */
+SCHED_FEAT(ARCH_POWER, false)
+
+SCHED_FEAT(HRTICK, false)
+SCHED_FEAT(DOUBLE_TICK, false)
+SCHED_FEAT(LB_BIAS, true)
+
+/*
+ * Spin-wait on mutex acquisition when the mutex owner is running on
+ * another cpu -- assumes that when the owner is running, it will soon
+ * release the lock. Decreases scheduling overhead.
+ */
+SCHED_FEAT(OWNER_SPIN, true)
+
+/*
+ * Decrement CPU power based on time not spent running tasks
+ */
+SCHED_FEAT(NONTASK_POWER, true)
+
+/*
+ * Queue remote wakeups on the target CPU and process them
+ * using the scheduler IPI. Reduces rq->lock contention/bounces.
+ */
+SCHED_FEAT(TTWU_QUEUE, true)
+
+SCHED_FEAT(FORCE_SD_OVERLAP, false)
+SCHED_FEAT(RT_RUNTIME_SHARE, true)