On Thu, Jun 23, 2016 at 03:33:08PM +0000, Christos Zoulas wrote: > In article <20160520091545.ga30...@britannica.bec.de>, > Joerg Sonnenberger <jo...@bec.de> 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
