Re: [PATCH -v2 1/9] rtmutex: Deboost before waking up the top waiter

[Peter Zijlstra]

On Mon, Sep 26, 2016 at 11:37:27AM -0400, Steven Rostedt wrote:
> On Mon, 26 Sep 2016 11:35:03 -0400
> Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> 
> > Especially now that the code after the spin_unlock(&hb->lock) is now a
> > critical section (preemption is disable). There's nothing obvious in
> > futex.c that says it is.
> 
> Not to mention, this looks like it will break PREEMPT_RT as wake_up_q()
> calls sleepable spin locks.

What locks would that be?