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Subject: Re: [hwloc-users] OpenGL GPU detection code
From: Brice Goglin (Brice.Goglin_at_[hidden])
Date: 2013-02-12 17:37:51


Stefan (or anybody else interested in hwloc GPU support),
Did you have any chance to look at this?
Brice

Le 01/02/2013 14:57, Brice Goglin a écrit :
> I just committed big changes to the display branch (and I also merged
> latest trunk changes).
>
> lstopo will now report things like this:
> PCI 10de:06d1
> GPU L#0 ":0.0"
> GPU L#1 "cuda0"
> GPU L#2 "nvml0"
>
>
> The changes include:
>
> 1) We don't have a "display" specific OS device anymore, it's just
> another kind of GPU among cuda, opencl and nvml. The name is the X
> server display name. There are string attributes in these new GL GPU OS
> devices (lstopo -v):
> GPU L#9 (Backend=GL GPUVendor="NVIDIA Corporation" GPUModel="Tesla
> C2050") ":0.2"
>
> 2) The gl component is now buildable as a plugin
>
> 3) Given (2), we can't expose internal GL routines in the public API. So
> hwloc/gl.h is just made of inline helpers as any other hwloc/foo.h. It
> now contains functions to convert between displays (name or port/device)
> and hwloc OS devices:
>
> hwloc_obj_t hwloc_gl_get_display_osdev_by_port_device(hwloc_topology_t
> topology, unsigned port, unsigned device)
> hwloc_obj_t hwloc_gl_get_display_osdev_by_name(hwloc_topology_t
> topology, const char *name)
> int hwloc_gl_get_display_by_osdev(hwloc_topology_t topology, hwloc_obj_t
> osdev,unsigned *port, unsigned *device)
>
> If you really need the PCI device, just use osdev->parent as documented.
> If you need the locality, use hwloc_get_non_io_ancestor(topology,
> osdev)->cpuset
> See tests/gl.c for examples.
>
> Please review hwloc/gl.h and let me know if that works for you. I hope I
> used the words port/device/server/screen as expected.
>
> The last thing on my TODO list is to decide is whether we keep the "GL"
> name or switch to something among display/X11/X/... for filenames and
> function names.
>
> Brice
>