Linux compatible setaffinity.

[Daniel Eischen]

On Sat, 12 Jan 2008, Jeff Roberson wrote:

> Now, there is one problem with the linux api that I want to discuss before I 
> commit it.  The current patch always works on curthread.  However, the api 
> allows for setting the binding of a pid.  I believe, although I'm not 
> certain, that pids and tids in linux are in the same number space.  It's not 
> clear to me whether you can set an affinity for an entire process and have it 
> effect an individual thread or whether you set it on a thread by thread 
> basis.  When supplying a non-curproc pid do you bind all threads in the 
> target process?
>
> Are our tids and pids in the same number space?  And are they available to 
> application programmers?  I haven't followed that very carefully.

I believe marcel made tids and pids disjoint so that any pid is
never equal to any tid.  But regardless, I don't think we want
to rely on that.  I would prefer the Solaris approach of specifying
what we want (pid, tid, jail id, etc) as an argument in the API
so there is no confusion.

-- 
DE