Re: sem_lock() vs qspinlocks

[Ingo Molnar]

* Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> On Fri, May 20, 2016 at 10:30:08AM +0200, Peter Zijlstra wrote:
> > On Thu, May 19, 2016 at 10:39:26PM -0700, Davidlohr Bueso wrote:
> > > Specifically
> > > for the 'cascade_cond' and 'cascade_flock' programs, which exhibit hangs in libc's
> > > semop() blocked waiting for zero.
> > 
> > OK; so I've been running:
> > 
> > while :; do
> >   bin/cascade_cond -E -C 200 -L -S -W -T 200  -I 2000000 ;
> >   bin/cascade_flock -E -C 200 -L -S -W -P 200 -I 5000000 ;
> > done
> > 
> > for a few minutes now and its not stuck and my machine didn't splat.
> > 
> > Am I not doing it right?
> 
> Hooray, it went *bang*..

I suspect a required step was to post about failure to reproduce!

	Ingo