May I add pthread_[gs]etconcurrency to the threads libraries?

[Jeff Roberson]

On Wed, 16 Apr 2003, Daniel Eischen wrote:

> On Wed, 16 Apr 2003, John Polstra wrote:
>
> > Hi Guys,
> >
> > Sergey Osokin sent me patches to add the standard
> > pthread_[gs]etconcurrency functions to our various threads
> > libraries.  I reviewed them and they're OK.  The functions don't do
> > anything significant, but they fill the need for this part of the
> > API.
> >
> > OK if I commit them this weekend?  The changes don't change anything
> > else.  They just add stuff.
>
> I'm about to implement them for real in libpthread.  I'd appreciate
> you not adding them to that.  I've got a slew of other changes that
> I want add to it very soon.
>
> They don't seem to make sense for libthr and libc_r unless it
> returns ENOTSUP.  libthr is 1:1, so it is meaning less there
> as well as libc_r.

It is not meaningless.  Please go ahead and implement stubs if you like.
I intended to implement a thr_setconcurrency that these can eventually
use.  I was just going to implement it as a simple counter on the proc
instead of using a full blown KSE structure just for this.

1:1 means one kernel thread for each user thread.  It doesn't say anything
about how many of those threads may run at a given time.  It also doesn't
force any scheduling scope or scheduling algorithm.

Cheers,
Jeff