[RFC] Add Arm cpu topology definition

[Vincent Guittot]

On 16 June 2011 10:55, Samuel Thibault <samuel.thibault at ens-lyon.org> wrote:
> Hello,
>
> Vincent Guittot, le Thu 16 Jun 2011 10:49:13 +0200, a écrit :
>> The affinity between Arm processors is defined in the MPIDR register.
>> We can identify which processors are in the same cluster,
>> and which ones have performance interdependency. The cpu topology
>>  of an Arm platform can be set thanks to this register and this topology
>> is then used by sched_mc and sched_smt.
>
> Cool!  Could you check that the hwloc tool gets also gets this
> information from userland through /sys, and/or send me the output of the
> hwloc-gather-topology tool from hwloc so we can add an testcase for
> this?
>

The output of hwloc-gather-topology is :

Machine (phys=0 local=280840KB total=280840KB)
  Socket #0 (phys=3)
    Core #0 (phys=0)
      PU #0 (phys=0)
    Core #1 (phys=1)
      PU #1 (phys=1)
depth 0:        1 Machine (type #1)
 depth 1:       1 Socket (type #3)
  depth 2:      2 Cores (type #5)
   depth 3:     2 PUs (type #6)
Topology not from this system

let me know if it's what you want

> Samuel
>