On Tue, 9 Jan 2024 at 14:25, Tvrtko Ursulin
<tvrtko.ursulin@xxxxxxxxxxxxxxx> wrote:
>
>
> On 09/01/2024 12:54, Daniel Vetter wrote:
> > On Tue, Jan 09, 2024 at 09:30:15AM +0000, Tvrtko Ursulin wrote:
> >>
> >> On 09/01/2024 07:56, Christian König wrote:
> >>> Am 07.12.23 um 19:02 schrieb Alex Deucher:
> >>>> Add shared stats. Useful for seeing shared memory.
> >>>>
> >>>> v2: take dma-buf into account as well
> >>>>
> >>>> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
> >>>> Cc: Rob Clark <robdclark@xxxxxxxxx>
> >>>> ---
> >>>> drivers/gpu/drm/amd/amdgpu/amdgpu_fdinfo.c | 4 ++++
> >>>> drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 11 +++++++++++
> >>>> drivers/gpu/drm/amd/amdgpu/amdgpu_object.h | 6 ++++++
> >>>> 3 files changed, 21 insertions(+)
> >>>>
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fdinfo.c
> >>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_fdinfo.c
> >>>> index 5706b282a0c7..c7df7fa3459f 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fdinfo.c
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fdinfo.c
> >>>> @@ -97,6 +97,10 @@ void amdgpu_show_fdinfo(struct drm_printer *p,
> >>>> struct drm_file *file)
> >>>> stats.requested_visible_vram/1024UL);
> >>>> drm_printf(p, "amd-requested-gtt:\t%llu KiB\n",
> >>>> stats.requested_gtt/1024UL);
> >>>> + drm_printf(p, "drm-shared-vram:\t%llu KiB\n",
> >>>> stats.vram_shared/1024UL);
> >>>> + drm_printf(p, "drm-shared-gtt:\t%llu KiB\n",
> >>>> stats.gtt_shared/1024UL);
> >>>> + drm_printf(p, "drm-shared-cpu:\t%llu KiB\n",
> >>>> stats.cpu_shared/1024UL);
> >>>> +
> >>>> for (hw_ip = 0; hw_ip < AMDGPU_HW_IP_NUM; ++hw_ip) {
> >>>> if (!usage[hw_ip])
> >>>> continue;
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> >>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> >>>> index d79b4ca1ecfc..1b37d95475b8 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> >>>> @@ -1287,25 +1287,36 @@ void amdgpu_bo_get_memory(struct amdgpu_bo *bo,
> >>>> struct amdgpu_mem_stats *stats)
> >>>> {
> >>>> uint64_t size = amdgpu_bo_size(bo);
> >>>> + struct drm_gem_object *obj;
> >>>> unsigned int domain;
> >>>> + bool shared;
> >>>> /* Abort if the BO doesn't currently have a backing store */
> >>>> if (!bo->tbo.resource)
> >>>> return;
> >>>> + obj = &bo->tbo.base;
> >>>> + shared = (obj->handle_count > 1) || obj->dma_buf;
> >>>
> >>> I still think that looking at handle_count is the completely wrong
> >>> approach, we should really only look at obj->dma_buf.
> >>
> >> Yeah it is all a bit tricky with the handle table walk. I don't think it is
> >> even possible to claim it is shared with obj->dma_buf could be the same
> >> process creating say via udmabuf and importing into drm. It is a wild
> >> scenario yes, but it could be private memory in that case. Not sure where it
> >> would leave us if we said this is just a limitation of a BO based tracking.
> >>
> >> Would adding a new category "imported" help?
> >>
> >> Hmm or we simply change drm-usage-stats.rst:
> >>
> >> """
> >> - drm-shared-<region>: <uint> [KiB|MiB]
> >>
> >> The total size of buffers that are shared with another file (ie. have more
> >> than than a single handle).
> >> """
> >>
> >> Changing ie into eg coule be get our of jail free card to allow the
> >> "(obj->handle_count > 1) || obj->dma_buf;" condition?
> >>
> >> Because of the shared with another _file_ wording would cover my wild
> >> udmabuf self-import case. Unless there are more such creative private import
> >> options.
> >
> > Yeah I think clarifying that we can only track sharing with other fd and
> > have no idea whether this means sharing with another process or not is
> > probably simplest. Maybe not exactly what users want, but still the
> > roughly best-case approximation we can deliver somewhat cheaply.
> >
> > Also maybe time for a drm_gem_buffer_object_is_shared() helper so we don't
> > copypaste this all over and then end up in divergent conditions? I'm
> > guessing that there's going to be a bunch of drivers which needs this
> > little helper to add drm-shared-* stats to their fdinfo ...
>
> Yeah I agree that works and i915 would need to use the helper too.
>
> I would only suggest to name it so the meaning of shared is obviously
> only about the fdinfo memory stats and no one gets a more meaningful
> idea about its semantics.
>
> We have drm_show_memory_stats and drm_print_memory_stats exported so
> perhaps something like drm_object_is_shared_for_memory_stats,
> drm_object_is_memory_stats_shared, drm_memory_stats_object_is_shared?
>
> And s/ie/eg/ in the above quoted drm-usage-stats.rst.
Ack on making it clear this helper would be for fdinfo memory stats
only. Sounds like a good idea to stop people from finding really
creative uses ...
-Sima
>
> Regards,
>
> Tvrtko
>
> >
> > Cheers, Sima
> >>
> >> Regards,
> >>
> >> Tvrtko
> >>
> >>>
> >>> Regards,
> >>> Christian.
> >>>
> >>>> +
> >>>> domain = amdgpu_mem_type_to_domain(bo->tbo.resource->mem_type);
> >>>> switch (domain) {
> >>>> case AMDGPU_GEM_DOMAIN_VRAM:
> >>>> stats->vram += size;
> >>>> if (amdgpu_bo_in_cpu_visible_vram(bo))
> >>>> stats->visible_vram += size;
> >>>> + if (shared)
> >>>> + stats->vram_shared += size;
> >>>> break;
> >>>> case AMDGPU_GEM_DOMAIN_GTT:
> >>>> stats->gtt += size;
> >>>> + if (shared)
> >>>> + stats->gtt_shared += size;
> >>>> break;
> >>>> case AMDGPU_GEM_DOMAIN_CPU:
> >>>> default:
> >>>> stats->cpu += size;
> >>>> + if (shared)
> >>>> + stats->cpu_shared += size;
> >>>> break;
> >>>> }
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
> >>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
> >>>> index d28e21baef16..0503af75dc26 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
> >>>> @@ -138,12 +138,18 @@ struct amdgpu_bo_vm {
> >>>> struct amdgpu_mem_stats {
> >>>> /* current VRAM usage, includes visible VRAM */
> >>>> uint64_t vram;
> >>>> + /* current shared VRAM usage, includes visible VRAM */
> >>>> + uint64_t vram_shared;
> >>>> /* current visible VRAM usage */
> >>>> uint64_t visible_vram;
> >>>> /* current GTT usage */
> >>>> uint64_t gtt;
> >>>> + /* current shared GTT usage */
> >>>> + uint64_t gtt_shared;
> >>>> /* current system memory usage */
> >>>> uint64_t cpu;
> >>>> + /* current shared system memory usage */
> >>>> + uint64_t cpu_shared;
> >>>> /* sum of evicted buffers, includes visible VRAM */
> >>>> uint64_t evicted_vram;
> >>>> /* sum of evicted buffers due to CPU access */
> >>>
> >
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
