[Intel-gfx] [PATCH 1/2] drm/i915: Track the purgeable objects on a separate eviction list

[Matthew Auld]

On Tue, 28 May 2019 at 20:50, Chris Wilson <chris at chris-wilson.co.uk> wrote:
>
> Currently the purgeable objects, I915_MADV_DONTNEED, as mixed in the
> normal bound/unbound lists. Every shrinker pass starts with an attempt
> to purge from this set of unneeded objects, which entails us doing a
> walk over both lists looking for any candidates. If there are none, and
> since we are shrinking we can reasonably assume that the lists are
> full!, this becomes a very slow futile walk.
>
> If we separate out the purgeable objects into own list, this search then
> becomes its own phase that is preferentially handled during shrinking.
> Instead the cost becomes that we then need to filter the purgeable list
> if we want to distinguish between bound and unbound objects.
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
> Cc: Matthew Auld <matthew.william.auld at gmail.com>

Makes sense,
Reviewed-by: Matthew Auld <matthew.william.auld at gmail.com>