From 326587b840785c60f5dc18557235a23bafefd620 Mon Sep 17 00:00:00 2001 From: Dmitry Adamushko Date: Fri, 25 Jan 2008 21:08:34 +0100 Subject: [PATCH] sched: fix goto retry in pick_next_task_rt() looking at it one more time: (1) it looks to me that there is no need to call sched_rt_ratio_exceeded() from pick_next_rt_entity() - [ for CONFIG_FAIR_GROUP_SCHED ] queues with rt_rq->rt_throttled are not within this 'tree-like hierarchy' (or whatever we should call it :-) - there is also no need to re-check 'rt_rq->rt_time > ratio' at this point as 'rt_rq->rt_time' couldn't have been increased since the last call to update_curr_rt() (which obviously calls sched_rt_ratio_esceeded()) well, it might be that 'ratio' for this rt_rq has been re-configured (and the period over which this rt_rq was active has not yet been finished)... but I don't think we should really take this into account. (2) now pick_next_rt_entity() must never return NULL, so let's change pick_next_task_rt() accordingly. Signed-off-by: Dmitry Adamushko Signed-off-by: Ingo Molnar --- kernel/sched_rt.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 2dac5ebb8bcb..274b40d7bef2 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -476,15 +476,12 @@ static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq, struct list_head *queue; int idx; - if (sched_rt_ratio_exceeded(rt_rq)) - goto out; - idx = sched_find_first_bit(array->bitmap); BUG_ON(idx >= MAX_RT_PRIO); queue = array->queue + idx; next = list_entry(queue->next, struct sched_rt_entity, run_list); - out: + return next; } @@ -494,7 +491,6 @@ static struct task_struct *pick_next_task_rt(struct rq *rq) struct task_struct *p; struct rt_rq *rt_rq; - retry: rt_rq = &rq->rt; if (unlikely(!rt_rq->rt_nr_running)) @@ -505,8 +501,7 @@ static struct task_struct *pick_next_task_rt(struct rq *rq) do { rt_se = pick_next_rt_entity(rq, rt_rq); - if (unlikely(!rt_se)) - goto retry; + BUG_ON(!rt_se); rt_rq = group_rt_rq(rt_se); } while (rt_rq);