Re: [pcp] pcp updates: multithreading etc.

["Frank Ch. Eigler" <fche@xxxxxxxxxx>]

Hi -

> I gave this a quick review. The idea of separate locks for individual 
> shared data objects looks ok to me. However, qa test 449 is hanging for me.

This appears improved with this patch on fche/multithread enough that
I can't make it fail here after thousands of runs.


commit d664a9d82aad11d64f8e3948fe1d51a7359ec3da
Author: Frank Ch. Eigler <fche@xxxxxxxxxx>
Date:   Thu May 5 11:24:44 2016 -0400

    libpcp multithread cont'd: lock ordering in __pmMultiThreaded and 
pmgetconfig
    
    Replacing libpcp lock in __pmMultiThreaded with a small non-nested
    lock, and similarly pmgetconfig().  Corrects occasional deadlock seen
    in qa/449 (src/multithread1).  Code still not helgrind-clean: the
    pmns.c code may need to go next.