Re: pthread library related

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

On Thu, Jun 23, 2016 at 03:33:08PM +0000, Christos Zoulas wrote:
> In article <20160520091545.GA30887%britannica.bec.de@localhost>,
> Joerg Sonnenberger  <joerg%bec.de@localhost> wrote:
> >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.
> 
> Yes, but should we commit the proposed ENOSYS stubs in the meantime just
> to have the functions available? I am not sure...

No, that would do more harm than good.

Joerg