On 03-08-2023 14:19, Tvrtko Ursulin wrote:
>
> On 03/08/2023 06:15, Iddamsetty, Aravind wrote:
>> On 27-07-2023 15:43, Tvrtko Ursulin wrote:
>>> From: Tvrtko Ursulin <tvrtko.ursu...@intel.com>
>>>
>>> Use the newly added drm_print_memory_stats helper to show memory
>>> utilisation of our objects in drm/driver specific fdinfo output.
>>>
>>> To collect the stats we walk the per memory regions object lists
>>> and accumulate object size into the respective drm_memory_stats
>>> categories.
>>>
>>> Objects with multiple possible placements are reported in multiple
>>> regions for total and shared sizes, while other categories are
>>> counted only for the currently active region.
>>>
>>> Signed-off-by: Tvrtko Ursulin <tvrtko.ursu...@intel.com>
>>> Cc: Aravind Iddamsetty <aravind.iddamse...@intel.com>
>>> Cc: Rob Clark <robdcl...@gmail.com>> ---
>>> drivers/gpu/drm/i915/i915_drm_client.c | 85 ++++++++++++++++++++++++++
>>> 1 file changed, 85 insertions(+)
>>>
>>> diff --git a/drivers/gpu/drm/i915/i915_drm_client.c
>>> b/drivers/gpu/drm/i915/i915_drm_client.c
>>> index a61356012df8..9e7a6075ee25 100644
>>> --- a/drivers/gpu/drm/i915/i915_drm_client.c
>>> +++ b/drivers/gpu/drm/i915/i915_drm_client.c
>>> @@ -45,6 +45,89 @@ void __i915_drm_client_free(struct kref *kref)
>>> }
>>> #ifdef CONFIG_PROC_FS
>>> +static void
>>> +obj_meminfo(struct drm_i915_gem_object *obj,
>>> + struct drm_memory_stats stats[INTEL_REGION_UNKNOWN])
>>> +{
>>> + struct intel_memory_region *mr;
>>> + u64 sz = obj->base.size;
>>> + enum intel_region_id id;
>>> + unsigned int i;
>>> +
>>> + /* Attribute size and shared to all possible memory regions. */
>>> + for (i = 0; i < obj->mm.n_placements; i++) {
>>> + mr = obj->mm.placements[i];
>>> + id = mr->id;
>>> +
>>> + if (obj->base.handle_count > 1)
>>> + stats[id].shared += sz;
>>> + else
>>> + stats[id].private += sz;
>>> + }
>>> +
>>> + /* Attribute other categories to only the current region. */
>>> + mr = obj->mm.region;
>>> + if (mr)
>>> + id = mr->id;
>>> + else
>>> + id = INTEL_REGION_SMEM;
>>> +
>>> + if (!obj->mm.n_placements) {
>>
>> I guess we do not expect to have n_placements set to public objects, is
>> that right?
>
> I think they are the only ones which can have placements. It is via
> I915_GEM_CREATE_EXT_MEMORY_REGIONS userspace is able to create them.
>
> My main conundrum in this patch is a few lines above, the loop which
> adds shared and private.
>
> Question is, if an object can be either smem or lmem, how do we want to
> report it? This patch adds the size for all possible regions and
> resident and active only to the currently active. But perhaps that is
> wrong. Maybe I should change it is only against the active region and
> multiple regions are just ignored. Then if object is migrated do access
> patterns or memory pressure, the total size would migrate too.
>
> I think I was trying to achieve something here (have more visibility on
> what kind of backing store clients are allocating) which maybe does not
> work to well with the current categories.
>
> Namely if userspace allocates say one 1MiB object with placement in
> either smem or lmem, and it is currently resident in lmem, I wanted it
> to show as:
>
> total-smem: 1 MiB
> resident-smem: 0
> total-lmem: 1 MiB
> resident-lmem: 1 MiB
>
> To constantly show how in theory client could be using memory from
> either region. Maybe that is misleading and should instead be:
>
> total-smem: 0
> resident-smem: 0
> total-lmem: 1 MiB
> resident-lmem: 1 MiB
>
> ?
I think the current implementation will not match with the memregion
info in query ioctl as well. While what you say is true I'm not sure if
there can be a client who is tracking the allocation say for an obj who
has 2 placements LMEM and SMEM, and might assume since I had made a
reservation in SMEM it shall not fail when i try to migrate there later.
Thanks,
Aravind.
>
> And then if/when the same object gets migrated to smem it changes to
> (lets assume it is also not resident any more but got swapped out):
>
> total-smem: 1 MiB
> resident-smem: 0
> total-lmem: 0
> resident-lmem: 0
>
> Regards,
>
> Tvrtko
>
>>> + if (obj->base.handle_count > 1)
>>> + stats[id].shared += sz;
>>> + else
>>> + stats[id].private += sz;
>>> + }
>>> +
>>> + if (i915_gem_object_has_pages(obj)) {
>>> + stats[id].resident += sz;
>>> +
>>> + if (!dma_resv_test_signaled(obj->base.resv,
>>> + dma_resv_usage_rw(true)))
>>> + stats[id].active += sz;
>>> + else if (i915_gem_object_is_shrinkable(obj) &&
>>> + obj->mm.madv == I915_MADV_DONTNEED)
>>> + stats[id].purgeable += sz;
>>> + }
>>> +}
>>> +
>>> +static void show_meminfo(struct drm_printer *p, struct drm_file *file)
>>> +{
>>> + struct drm_memory_stats stats[INTEL_REGION_UNKNOWN] = {};
>>> + struct drm_i915_file_private *fpriv = file->driver_priv;
>>> + struct i915_drm_client *client = fpriv->client;
>>> + struct drm_i915_private *i915 = fpriv->i915;
>>> + struct drm_i915_gem_object *obj;
>>> + struct intel_memory_region *mr;
>>> + struct list_head *pos;
>>> + unsigned int id;
>>> +
>>> + /* Public objects. */
>>> + spin_lock(&file->table_lock);
>>> + idr_for_each_entry(&file->object_idr, obj, id)
>>> + obj_meminfo(obj, stats);
>>> + spin_unlock(&file->table_lock);
>>> +
>>> + /* Internal objects. */
>>> + rcu_read_lock();
>>> + list_for_each_rcu(pos, &client->objects_list) {
>>> + obj = i915_gem_object_get_rcu(list_entry(pos, typeof(*obj),
>>> + client_link));
>>> + if (!obj)
>>> + continue;
>>> + obj_meminfo(obj, stats);
>>> + i915_gem_object_put(obj);
>>> + }
>>> + rcu_read_unlock();
>>> +
>>> + for_each_memory_region(mr, i915, id)
>>> + drm_print_memory_stats(p,
>>> + &stats[id],
>>> + DRM_GEM_OBJECT_RESIDENT |
>>> + DRM_GEM_OBJECT_PURGEABLE,
>>> + mr->name);
>>> +}
>>> +
>>> static const char * const uabi_class_names[] = {
>>> [I915_ENGINE_CLASS_RENDER] = "render",
>>> [I915_ENGINE_CLASS_COPY] = "copy",
>>> @@ -106,6 +189,8 @@ void i915_drm_client_fdinfo(struct drm_printer
>>> *p, struct drm_file *file)
>>> *
>>> ******************************************************************
>>> */
>>> + show_meminfo(p, file);
>>> +
>>> if (GRAPHICS_VER(i915) < 8)
>>> return;
>>>
>>
>>
>>
