From ad4b78bbcbab66998b05d422ac6106b645796e54 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 16 Sep 2009 12:31:31 +0200 Subject: sched: Add new wakeup preemption mode: WAKEUP_RUNNING Create a new wakeup preemption mode, preempt towards tasks that run shorter on avg. It sets next buddy to be sure we actually run the task we preempted for. Test results: root@twins:~# while :; do :; done & [1] 6537 root@twins:~# while :; do :; done & [2] 6538 root@twins:~# while :; do :; done & [3] 6539 root@twins:~# while :; do :; done & [4] 6540 root@twins:/home/peter# ./latt -c4 sleep 4 Entries: 48 (clients=4) Averages: ------------------------------ Max 4750 usec Avg 497 usec Stdev 737 usec root@twins:/home/peter# echo WAKEUP_RUNNING > /debug/sched_features root@twins:/home/peter# ./latt -c4 sleep 4 Entries: 48 (clients=4) Averages: ------------------------------ Max 14 usec Avg 5 usec Stdev 3 usec Disabled by default - needs more testing. Signed-off-by: Peter Zijlstra Acked-by: Mike Galbraith Signed-off-by: Ingo Molnar LKML-Reference: --- include/linux/sched.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/sched.h b/include/linux/sched.h index b4a39bb2b4a..8af3d249170 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1113,6 +1113,8 @@ struct sched_entity { u64 start_runtime; u64 avg_wakeup; + u64 avg_running; + #ifdef CONFIG_SCHEDSTATS u64 wait_start; u64 wait_max; -- cgit v1.2.3