From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Cooper Subject: Re: Hwloc with Xen host topology Date: Thu, 2 Jan 2014 21:50:06 +0000 Message-ID: <52C5DF0E.1030500@citrix.com> References: <52C5CB89.70804@citrix.com> <20140102212453.GT29132@type.youpi.perso.aquilenet.fr> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20140102212453.GT29132@type.youpi.perso.aquilenet.fr> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Samuel Thibault , Xen-devel List List-Id: xen-devel@lists.xenproject.org On 02/01/14 21:24, Samuel Thibault wrote: > Hello, > > Andrew Cooper, le Thu 02 Jan 2014 20:26:49 +0000, a =E9crit : >> Cores are numbered per-socket in Xen, while sockets, >> numa nodes and cpus are numbered on an absolute scale. There is >> currently a gross hack in my hwloc code which adds (socket_id * >> cores_per_socket * threads_per_core) onto each core id to make them >> similarly numbered on an absolute scale. This is fine for a homogeneous >> system, but not for a hetrogeneous system. > BTW, hwloc does not need these physical ids to be unique, it can cope > with duplication and whatnot. That said, having a coherent interface at > the Xen layer would be a good thing, indeed :) > > Samuel If I take out the described hack, I am presented with **************************************************************************** * hwloc has encountered what looks like an error from the operating system. * * object (Core P#0 cpuset 0x30000003) intersection without inclusion! * Error occurred in topology.c line 853 * * Please report this error message to the hwloc user's mailing list, * along with the output from the hwloc-gather-topology.sh script. **************************************************************************** Which I took to mean "I have done something stupid". I looked and saw that I was attempting to insert a second Core P#0 object with a different cpuset and decided to renumber the cores so they didn't overlap in physical ids. If you believe that this should indeed work, then I guess I need to raise a bug... ~Andrew