[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>
diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c
index bb16c22..2fb0e63 100644
--- a/arch/powerpc/platforms/cell/spufs/sched.c
+++ b/arch/powerpc/platforms/cell/spufs/sched.c
@@ -294,9 +294,10 @@
{
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 @@
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);
}
- 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 @@
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 @@
}
}
- del_timer_sync(&spusched_timer);
return 0;
}
@@ -732,6 +731,8 @@
}
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 @@
remove_proc_entry("spu_loadavg", NULL);
+ del_timer_sync(&spusched_timer);
kthread_stop(spusched_task);
for (node = 0; node < MAX_NUMNODES; node++) {