On Fri, 2010-07-09 at 15:32 -0700, Darren Hart wrote: > rtmutex proxy locking complicates the logic a bit and opens up > the possibility for a task to wake and attempt to take another > sleeping lock without knowing it has been enqueued on another > lock already. Add a BUG_ON to catch this scenario early. > > Signed-off-by: Darren Hart <dvhltc@xxxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > Cc: Ingo Molnar <mingo@xxxxxxx> > Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx> > Cc: John Kacur <jkacur@xxxxxxxxxx> > Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> > Cc: Mike Galbraith <efault@xxxxxx> > --- > kernel/rtmutex.c | 3 +++ > 1 files changed, 3 insertions(+), 0 deletions(-) > > diff --git a/kernel/rtmutex.c b/kernel/rtmutex.c > index baac7d9..22f9d18 100644 > --- a/kernel/rtmutex.c > +++ b/kernel/rtmutex.c > @@ -459,6 +459,9 @@ static int task_blocks_on_rt_mutex(struct rt_mutex *lock, > top_waiter = rt_mutex_top_waiter(lock); > plist_add(&waiter->list_entry, &lock->wait_list); > > + /* Tasks can only block on one lock at a time. */ > + BUG_ON(task->pi_blocked_on != NULL); WARN_ON may be better. Since it may not cause a system crash or other huge bug if it is not true. -- Steve > + > task->pi_blocked_on = waiter; > > raw_spin_unlock(&task->pi_lock); -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
