diff options
| author | Mike Galbraith <efault@gmx.de> | 2011-07-27 17:14:55 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2011-08-14 12:00:43 +0200 |
| commit | c350a04efd1c89cd256b2abc8f07a21d0d53ff24 (patch) | |
| tree | 81b7ad7cd7e86c21aeb81fcfe68bb38892e1ddbb | |
| parent | sched: Kill WAKEUP_PREEMPT (diff) | |
| download | linux-c350a04efd1c89cd256b2abc8f07a21d0d53ff24.tar.xz linux-c350a04efd1c89cd256b2abc8f07a21d0d53ff24.zip | |
sched: fix broken SCHED_RESET_ON_FORK handling
Setting child->prio = current->normal_prio _after_ SCHED_RESET_ON_FORK has
been handled for an RT parent gives birth to a deranged mutant child with
non-RT policy, but RT prio and sched_class.
Move PI leakage protection up, always set priorities and weight, and if the
child is leaving RT class, reset rt_priority to the proper value.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1311779695.8691.2.camel@marge.simson.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | kernel/sched.c | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index b1e8f0eca1f9..cf427bb2b65e 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2844,19 +2844,23 @@ void sched_fork(struct task_struct *p) p->state = TASK_RUNNING; /* + * Make sure we do not leak PI boosting priority to the child. + */ + p->prio = current->normal_prio; + + /* * Revert to default priority/policy on fork if requested. */ if (unlikely(p->sched_reset_on_fork)) { - if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) { + if (task_has_rt_policy(p)) { p->policy = SCHED_NORMAL; - p->normal_prio = p->static_prio; - } - - if (PRIO_TO_NICE(p->static_prio) < 0) { p->static_prio = NICE_TO_PRIO(0); - p->normal_prio = p->static_prio; - set_load_weight(p); - } + p->rt_priority = 0; + } else if (PRIO_TO_NICE(p->static_prio) < 0) + p->static_prio = NICE_TO_PRIO(0); + + p->prio = p->normal_prio = __normal_prio(p); + set_load_weight(p); /* * We don't need the reset flag anymore after the fork. It has @@ -2865,11 +2869,6 @@ void sched_fork(struct task_struct *p) p->sched_reset_on_fork = 0; } - /* - * Make sure we do not leak PI boosting priority to the child. - */ - p->prio = current->normal_prio; - if (!rt_prio(p->prio)) p->sched_class = &fair_sched_class; |