On Thu, Aug 01, 2013 at 03:54:01PM +0200, Jiri Olsa wrote:
> On Thu, Aug 01, 2013 at 03:49:36PM +0200, Frederic Weisbecker wrote:
> > On Thu, Aug 01, 2013 at 03:32:17PM +0200, Jiri Olsa wrote:
> > > On Thu, Aug 01, 2013 at 03:28:34PM +0200, Frederic Weisbecker wrote:
> > >
> > > SNIP
> > >
> > > > > also for following case:
> > > > >
> > > > > count = atomic_inc_return(&nr_callchain_events);
> > > > > if (WARN_ON_ONCE(count < 1)) {
> > > > > err = -EINVAL;
> > > > > goto exit;
> > > > > }
> > > > >
> > > > > seems like it screws the count
> > > >
> > > > I'm not sure what you mean here. You mean that it could be negative
> > > > when the dec is done
> > > > outside the lock?
> > >
> > > yes
> > >
> >
> > I don't understand why.
>
> ah ok, with the count being 0 the nr_callchain_events still
> increments right? then it's ok..
Yep. But I still need to move the dec into the lock though.
Thanks for catching this!
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
