Re: [PATCH 6/9] drm/i915: Wire up shrinkctl->nr_scanned

Joonas Lahtinen
2017-10-16T10:46:15Z

On Fri, 2017-10-13 at 21:26 +0100, Chris Wilson wrote:
> shrink_slab() allows us to report back the number of objects we
> successfully scanned (out of the target shrinkctl->nr_to_scan). As
> report the number of pages owned by each GEM object as a separate item
> to the shrinker, we cannot precisely control the number of shrinker
> objects we scan on each pass; and indeed may free more than requested.
> If we fail to tell the shrinker about the number of objects we process,
> it will continue to hold a grudge against us as any objects left
> unscanned are added to the next reclaim -- and so we will keep on
> "unfairly" shrinking our own slab in comparison to other slabs.
>
> v2: fixup the misplaced addition, we want to count everything we scan
> (to match the number we reported earlier) not just the objects we
> successfully validated and freed.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

Umm, full explanation and "v2" is bit misleading. Should not this be
one Fixes: if significant enough, or just a clear reference to
912d572d63b8 ("drm/i915: wire up shrinkctl->nr_scanned")?

Change itself is;

Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Regards, Joonas
--
Joonas Lahtinen
Open Source Technology Center
Intel Corporation