RE: [PATCH v4] libgfortran: Replace mutex with rwlock

["Zhu, Lipeng" <lipeng.zhu@intel.com>]

> 
> Hi Lipeng,
> 
> >>> Sure, as your comments, in the patch V6, I added 3 test cases with
> >>> OpenMP to test different cases in concurrency respectively:
> >>> 1. find and create unit very frequently to stress read lock and write lock.
> >>> 2. only access the unit which exist in cache to stress read lock.
> >>> 3. access the same unit in concurrency.
> >>> For the third test case, it also help to find a bug:  When unit
> >>> can't be found in cache nor unit list in read phase, then threads
> >>> will try to acquire write lock to insert the same unit, this will
> >>> cause duplicate key
> >> error.
> >>> To fix this bug, I get the unit from unit list once again before
> >>> insert in write
> >> lock.
> >>> More details you can refer the patch v6.
> >>>
> >>
> >> Could you help to review this update? I really appreciate your assistance.
> >>
> 
> > Could you help to review this update?  Any concern will be appreciated.
> 
> Fortran parts are OK (I think I wrote that already), we need somebody for the
> non-Fortran parts.
> 
Hi Thomas,

Thanks for your response. Very appreciate for your patience and help.

> Jakub, could you maybe take a look?
> 
> Best regards
> 
> 	Thomas

Hi Jakub,

Can you help to take a look at the change for libgcc part that added 
several rwlock macros in libgcc/gthr-posix.h?

Best Regards,
Lipeng Zhu