diff options
| author | Peter Williams <pwil3058@bigpond.net.au> | 2006-12-19 12:48:50 +1000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-21 00:11:51 -0800 |
| commit | bc947631d1d532c758f8fcbdeb1f7fc2f4c863f8 (patch) | |
| tree | 3795bf4735650e4a1af417f7c97f1d7103401308 /kernel/sched.c | |
| parent | 136f1e7a8cb7d17ff91706518549697071640ae4 (diff) | |
[PATCH] sched: improve efficiency of sched_fork()
Problem:
sched_fork() has always called scheduler_tick() in some (unlikely)
circumstances in order to update the current task in light of those
circumstances. It has always been the case that the work done by
scheduler_tick() was more than was required to handle the problem in
hand but no harm was done except for the waste of a few CPU cycles.
However, the splitting of scheduler_tick() into two procedures in
2.6.20-rc1 enables the wasted cycles to be saved as the new procedure
task_running_tick() does all the work that is required to rectify the
problem being handled.
Solution:
Replace the call to scheduler_tick() in sched_fork() with a call to
task_running_tick().
Signed-off-by: Peter Williams <pwil3058@bigpond.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'kernel/sched.c')
| -rw-r--r-- | kernel/sched.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 5cd833bc2173..b81ed8703f70 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -1567,6 +1567,7 @@ int fastcall wake_up_state(struct task_struct *p, unsigned int state) return try_to_wake_up(p, state, 0); } +static void task_running_tick(struct rq *rq, struct task_struct *p); /* * Perform scheduler related setup for a newly forked process p. * p is forked by current. @@ -1627,7 +1628,7 @@ void fastcall sched_fork(struct task_struct *p, int clone_flags) * runqueue lock is not a problem. */ current->time_slice = 1; - scheduler_tick(); + task_running_tick(cpu_rq(cpu), current); } local_irq_enable(); put_cpu(); |