From c77239b8be74f775142d9dd01041e2ce864ba20d Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 29 Jun 2007 10:58:05 +1000 Subject: [PATCH] [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 Signed-off-by: Jeremy Kerr Signed-off-by: Paul Mackerras --- arch/powerpc/platforms/cell/spufs/sched.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c index bb16c22360d5..2fb0e63344cc 100644 --- a/arch/powerpc/platforms/cell/spufs/sched.c +++ b/arch/powerpc/platforms/cell/spufs/sched.c @@ -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); } - 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++) {