From 23b0fdfc9299b137bd126e9dc22f62a59dae546d Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 13 Feb 2008 15:45:39 +0100 Subject: sched: rt-group: deal with PI Steven mentioned the fun case where a lock holding task will be throttled. Simple fix: allow groups that have boosted tasks to run anyway. If a runnable task in a throttled group gets boosted the dequeue/enqueue done by rt_mutex_setprio() is enough to unthrottle the group. This is ofcourse not quite correct. Two possible ways forward are: - second prio array for boosted tasks - boost to a prio ceiling (this would also work for deadline scheduling) Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- kernel/sched.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'kernel/sched.c') diff --git a/kernel/sched.c b/kernel/sched.c index 88a17c7128c3..cecaea67ae9b 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -362,6 +362,8 @@ struct rt_rq { u64 rt_time; #ifdef CONFIG_FAIR_GROUP_SCHED + unsigned long rt_nr_boosted; + struct rq *rq; struct list_head leaf_rt_rq_list; struct task_group *tg; @@ -7112,6 +7114,7 @@ static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq) rt_rq->rt_throttled = 0; #ifdef CONFIG_FAIR_GROUP_SCHED + rt_rq->rt_nr_boosted = 0; rt_rq->rq = rq; #endif } -- cgit v1.2.2