[RFC 4/6] drm: Add simple fdinfo memory helpers

[Rob Clark]

On Mon, Apr 17, 2023 at 8:56 AM Tvrtko Ursulin
<tvrtko.ursulin at linux.intel.com> wrote:
>
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
>
> For drivers who only wish to show one memory region called 'system,
> and only account the GEM buffer object handles under it.
>
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> ---
>  drivers/gpu/drm/drm_file.c | 45 ++++++++++++++++++++++++++++++++++++++
>  include/drm/drm_file.h     |  6 +++++
>  2 files changed, 51 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c
> index e202f79e816d..1e70669dddf7 100644
> --- a/drivers/gpu/drm/drm_file.c
> +++ b/drivers/gpu/drm/drm_file.c
> @@ -872,6 +872,51 @@ void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
>  }
>  EXPORT_SYMBOL(drm_send_event);
>
> +static void
> +add_obj(struct drm_gem_object *obj, struct drm_fdinfo_memory_stat *stats)
> +{
> +       u64 sz = obj->size;
> +
> +       stats[0].size += sz;
> +
> +       if (obj->handle_count > 1)
> +               stats[0].shared += sz;
> +
> +       if (!dma_resv_test_signaled(obj->resv, dma_resv_usage_rw(true)))
> +               stats[0].active += sz;
> +
> +       /* Not supported. */
> +       stats[0].resident = ~0ull;
> +       stats[0].purgeable = ~0ull;

Hmm, this kinda makes the simple helper not very useful.  In my
version, you get something that is useful for all UMA drivers (which
all, IIRC, have some form of madv ioctl).  I was kinda imagining that
for ttm drivers, my print_memory_stats() would just become a helper
and that TTM (or "multi-region") drivers would have their own thing.

BR,
-R

> +}
> +
> +char **
> +drm_query_fdinfo_system_region(struct drm_device *dev, unsigned int *num)
> +{
> +       static char *region[] = {
> +               "system",
> +       };
> +
> +       *num = 1;
> +
> +       return region;
> +}
> +EXPORT_SYMBOL(drm_query_fdinfo_system_region);
> +
> +void
> +drm_query_fdinfo_system_memory(struct drm_file *file,
> +                              struct drm_fdinfo_memory_stat *stats)
> +{
> +       struct drm_gem_object *obj;
> +       int id;
> +
> +       spin_lock(&file->table_lock);
> +       idr_for_each_entry(&file->object_idr, obj, id)
> +               add_obj(obj, stats);
> +       spin_unlock(&file->table_lock);
> +}
> +EXPORT_SYMBOL(drm_query_fdinfo_system_memory);
> +
>  static void
>  print_stat(struct drm_printer *p, const char *stat, const char *region, u64 sz)
>  {
> diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h
> index 00d48beeac5c..dd7c6fb2c975 100644
> --- a/include/drm/drm_file.h
> +++ b/include/drm/drm_file.h
> @@ -383,6 +383,12 @@ struct drm_fdinfo_memory_stat {
>         u64 active;
>  };
>
> +char **drm_query_fdinfo_system_region(struct drm_device *dev,
> +                                     unsigned int *num);
> +void drm_query_fdinfo_system_memory(struct drm_file *file,
> +                                   struct drm_fdinfo_memory_stat *stats);
> +
> +
>  /**
>   * drm_is_primary_client - is this an open file of the primary node
>   * @file_priv: DRM file
> --
> 2.37.2
>