[POWERPC] spusched: Disable tick when not needed

Only enable the scheduler tick if we have any context waiting to be
scheduled.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Christoph Hellwig 2007-06-29 10:58:05 +10:00 committed by Paul Mackerras
parent 08c9692b16
commit c77239b8be

View File

@ -294,9 +294,10 @@ static void __spu_add_to_rq(struct spu_context *ctx)
{
int prio = ctx->prio;
spu_prio->nr_waiting++;
list_add_tail(&ctx->rq, &spu_prio->runq[prio]);
set_bit(prio, spu_prio->bitmap);
if (!spu_prio->nr_waiting++)
__mod_timer(&spusched_timer, jiffies + SPUSCHED_TICK);
}
static void __spu_del_from_rq(struct spu_context *ctx)
@ -304,11 +305,13 @@ static void __spu_del_from_rq(struct spu_context *ctx)
int prio = ctx->prio;
if (!list_empty(&ctx->rq)) {
if (!--spu_prio->nr_waiting)
del_timer(&spusched_timer);
list_del_init(&ctx->rq);
spu_prio->nr_waiting--;
}
if (list_empty(&spu_prio->runq[prio]))
clear_bit(prio, spu_prio->bitmap);
}
}
static void spu_prio_wait(struct spu_context *ctx)
@ -654,9 +657,6 @@ static int spusched_thread(void *unused)
struct spu *spu, *next;
int node;
setup_timer(&spusched_timer, spusched_wake, 0);
__mod_timer(&spusched_timer, jiffies + SPUSCHED_TICK);
while (!kthread_should_stop()) {
set_current_state(TASK_INTERRUPTIBLE);
schedule();
@ -670,7 +670,6 @@ static int spusched_thread(void *unused)
}
}
del_timer_sync(&spusched_timer);
return 0;
}
@ -732,6 +731,8 @@ int __init spu_sched_init(void)
}
spin_lock_init(&spu_prio->runq_lock);
setup_timer(&spusched_timer, spusched_wake, 0);
spusched_task = kthread_run(spusched_thread, NULL, "spusched");
if (IS_ERR(spusched_task)) {
err = PTR_ERR(spusched_task);
@ -762,6 +763,7 @@ void __exit spu_sched_exit(void)
remove_proc_entry("spu_loadavg", NULL);
del_timer_sync(&spusched_timer);
kthread_stop(spusched_task);
for (node = 0; node < MAX_NUMNODES; node++) {