The modification of the default cpuset (to exclude CPUs 0-9) is done by our local installation.  I assume the vanilla FreeBSD 7.3 that we're based on does not monkey with the default cpuset.

I believe modifying your own cpuset is not a privileged operation in FreeBSD.  The cpuset executable is not setuid root and is usable by regular users.

I think you can move the lstopo process to cpuset 0 (which includes all CPUs) by calling cpuset_setid(), and that should take care of the issue.


On Thu, Oct 11, 2012 at 10:13 AM, Brice Goglin <Brice.Goglin@inria.fr> wrote:
(forwarding your mail to the list, and replying)

Good to know that it works, thanks for testing. I released 1.5.1rc1 today, it should work fine as well.

You say that the cpuset does not contain 0-9 by default on this hardware. This is something specific to your installation, I guess? Nothing that happens by default on a default FreeBSD install, right?

Is the cpuset-modification a root-only operation on FreeBSD? If so lstopo wouldn't be able to expand the cpuset at startup.

lstopo has a --whole-system option to ignore such limitations. Unfortunately the x86 backend that hwloc uses on FreeBSD requires that we bind to each individual core to get its locality information, so that won't help unless lstopo can indeed remove the cpuset first.

Brice



-------- Message original --------
Sujet: Re: [hwloc-users] hwloc 1.5, freebsd and linux output on the same hardware
Date : Thu, 11 Oct 2012 10:02:55 -0600
De : Sebastian Kuzminsky <seb@lineratesystems.com>
Pour : Brice Goglin <Brice.Goglin@inria.fr>


Ok, it's our fault, sort of.

We use cpusets, and by default on this hardware CPUs 0-9 are denied to most processes (including lstopo).  If I explicitly change the cpuset of lstopo to include CPUs 0-9, it runs correctly.

Maybe lstopo should expand its cpuset to be fully inclusive at startup?  I'll be happy to test patches if you want.




On Thu, Oct 11, 2012 at 9:27 AM, Sebastian Kuzminsky <seb@lineratesystems.com> wrote:
On Thu, Oct 11, 2012 at 2:39 AM, Brice Goglin <Brice.Goglin@inria.fr> wrote:
Le 06/10/2012 01:03, Sebastian Kuzminsky a écrit :
> Hm.  It may be that we're doing something funny and reserving those
> CPUs.  I'll run some tests on Monday and get back to you.

(replying outside of the hwloc mailing list)

Did you have a chance to look at this?
I am about to release a hwloc 1.5.1rc1. It'd be good to get your
feedback before we do the final 1.5.1 (likely next week).

Oops, thanks for the reminder...  I got side tracked on other stuff, but I have some time this morning to devote to this. I'll get back to you soon.


--
Sebastian Kuzminsky
Sr Software Engineer, Linerate Systems




--
Sebastian Kuzminsky
Sr Software Engineer, Linerate Systems




--
Sebastian Kuzminsky
Sr Software Engineer, Linerate Systems