From ffd44db5f02af32bcc25a8eb5981bf02a141cdab Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 10 Nov 2009 20:12:01 +0100 Subject: [PATCH] sched: Make sure task has correct sched_class after policy change From the code in rt_mutex_setprio(), it is evident that the intention is that task's with a RT 'prio' value as a consequence of receiving a PI boost also have their 'sched_class' field set to '&rt_sched_class'. However, Peter noticed that the code in __setscheduler() could result in this intention being frustrated. Fix it. Reported-by: Peter Williams Signed-off-by: Peter Zijlstra Cc: Mike Galbraith LKML-Reference: <1257880321.4108.457.camel@laptop> Signed-off-by: Ingo Molnar --- kernel/sched.c | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index ad37776cc39..43e61fa04dc 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -6159,22 +6159,14 @@ __setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio) BUG_ON(p->se.on_rq); p->policy = policy; - switch (p->policy) { - case SCHED_NORMAL: - case SCHED_BATCH: - case SCHED_IDLE: - p->sched_class = &fair_sched_class; - break; - case SCHED_FIFO: - case SCHED_RR: - p->sched_class = &rt_sched_class; - break; - } - p->rt_priority = prio; p->normal_prio = normal_prio(p); /* we are holding p->pi_lock already */ p->prio = rt_mutex_getprio(p); + if (rt_prio(p->prio)) + p->sched_class = &rt_sched_class; + else + p->sched_class = &fair_sched_class; set_load_weight(p); }