From 8493e110a637c273b4d38e79f7ce3c3ad1812931 Mon Sep 17 00:00:00 2001 From: Matthew Auld Date: Mon, 23 Mar 2020 13:08:21 +0000 Subject: [PATCH] drm/i915/selftests: mark huge_gem_object as not shrinkable It looks like some callers expect a non-volatile object, that they do not want the contents of the pages lost if they happen to not be looking at it. The shrinker however sees that we mark the pages as DONTNEED and believes that it can freely reap them. However, since the huge object use plain pages, they cannot be swapped out as they have no backing storge, and the only way we can shrink them is by discarding the contents. In light of the callers wanting to keep the contents around, both IS_SHRINKABLE and marking the pages as volatile are incorrect. If we drop the IS_SHRINKABLE flag we avoid the immediate issue of the shrinker accidentally removing valuable content. We will have to remember that a huge object is not suitable for exercising the shrinker interaction -- although we can introduce a shrinkable one if we require. Signed-off-by: Matthew Auld Reviewed-by: Chris Wilson Signed-off-by: Chris Wilson Link: https://patchwork.freedesktop.org/patch/msgid/20200323130821.47914-1-matthew.auld@intel.com --- drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c b/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c index fa16f2c3..2b46c65 100644 --- a/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c +++ b/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c @@ -88,8 +88,7 @@ static void huge_put_pages(struct drm_i915_gem_object *obj, } static const struct drm_i915_gem_object_ops huge_ops = { - .flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE | - I915_GEM_OBJECT_IS_SHRINKABLE, + .flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE, .get_pages = huge_get_pages, .put_pages = huge_put_pages, }; -- 2.7.4