Re: [pcp] libpcp multithreading - next steps

[Dave Brolley <brolley@xxxxxxxxxx>]

On 07/26/2016 05:09 PM, Frank Ch. Eigler wrote:
> kenj wrote:
>
> > [...]  This commit contains the contentious (in my mind)
> > __pmHandleToPtr_unlocked() change ... reviewing this pre-empts the
> > discussion about how to fix the context create/destroy race that I
> > wanted us to resolve as a first step of restating this effort.
> Sure.  Let's resolve it!
This discussion seems to have stalled again. I assume that one or both 
of you (Frank and/or Ken) is familiar with this particular race. Has 
there been a solution proposed? If so, was there an implementation? If 
so, where is it? (branch + commit).
> > I also am unconvinced that any lock inversion existed in the
> > original design and implementation
> What are you referring to as "original"?
>
>
> > and would like to understand that (if it exists) before we embark on
> > a development path that relies on helgrind to find lock inversions
> > rather than design to avoid lock inversions.
> It sounds as though you are suspicious that helgrind is unreliable:
> that the lock inversion errors are mistaken.  Let me assure you that
> every case I've studied, it was genuine.
It might be helpful if you could point out each of these cases and how 
the inversion was addressed by your changes.
Dave