OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

sched: optimize task_new_fair() 

due to the fact that we no longer keep the 'current' within the tree, 
dequeue/enqueue_entity() is useless for the 'current' in 
task_new_fair(). We are about to reschedule and 
sched_class->put_prev_task() will put the 'current' back into the tree, 
based on its new key.

   text    data     bss     dec     hex filename
  24388    2734      20   27142    6a06 sched.o.before
  24341    2734      20   27095    69d7 sched.o.after

Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Dmitry Adamushko 2007-10-15 17:00:08 +02:00 committed by Ingo Molnar
parent 75d4ef16a6
commit 87fefa381e
1 changed files with 4 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
kernel/sched_fair.c
View File

@ -972,10 +972,11 @@ static void task_new_fair(struct rq *rq, struct task_struct *p)
if (sysctl_sched_child_runs_first &&
curr->vruntime < se->vruntime) {
dequeue_entity(cfs_rq, curr, 0);
/*
* Upon rescheduling, sched_class::put_prev_task() will place
* 'current' within the tree based on its new key value.
*/
swap(curr->vruntime, se->vruntime);
enqueue_entity(cfs_rq, curr, 0);
}
update_stats_enqueue(cfs_rq, se);