getaffinity/setaffinity and cpu sets.

[Jeff Roberson]

On Thu, 21 Feb 2008, David Schultz wrote:

> I have no specific comments, but I wanted to point out that the
> Solaris kernel team put a lot of thought into coming up with a
> flexible processor binding API for Solaris 10 that meshes well
> with jails (a.k.a. zones in Solaris). It might be worthwhile to
> investigate what good ideas they might have had, and to decide if
> compatibility is worthwhile:

Well interestingly enough I came up with an almost identical thing but 
with fewer features.  If someone wanted to add the missing features I'm 
fine with that.  I don't know if we want to or are free to copy the api 
exactly.

>
>    http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/sys/pset.h
>
> There are manpages for this stuff somewhere. pset_create and
> pset_destroy obviously create and delete processor set definitions.
> pset_bind binds a particular process / thread / session / jail
> to a processor set, similar to your CPU_WHICH_* flags, I think,
> but with more options.
>

I didn't see the header but I read some web articles about it.  The only 
real discrepancy is whether you explicitly destroy them or they disappear 
when the last processor leaves the set.  I could be convinced to do 
either, but so far I'm leaning towards automatic destruction.

Hopefully someone who is involved with jails will work with me to 
integrate the two.  I intend only to implement the infrastructure required 
to create and modify sets.  Someone who is jail savvy will need to apply 
the set and the appropriate security restrictions.

Thanks,
Jeff