Re: pthread library related

[Joerg Sonnenberger <joerg%bec.de@localhost>]

On Thu, May 19, 2016 at 01:36:29PM -0400, Christos Zoulas wrote:
> You can see how FreeBSD is implementing them; it is a lot of code to do
> this and would require some architectural review. The relevant files are:
> 
> http://nxr.netbsd.org/xref/src-freebsd/lib/libthr/thread/thr_pshared.c
> http://nxr.netbsd.org/xref/src-freebsd/lib/libthr/thread/thr_barrierattr.c
> http://nxr.netbsd.org/xref/src-freebsd/sys/kern/kern_umtx.c
> 
> We don't have such mutex functionality in our kernel. Implementing this
> would be a GSoC project in itself.

I don't think we want to use futexes in general. I'm not even sure I
care about performance for something horrible like "robust" mutexes at
all. A good starting point might to just extend the existing semaphores,
if necessary.

Joerg