drm/i915: Remove the duplicated logic between the two shrink phases

We can use the same logic to walk the different bound/unbound lists
during shrinker (as the unbound list is a degenerate case of the bound
list), slightly compacting the code.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index e05e006..2719c25 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1945,7 +1945,14 @@ unsigned long
 i915_gem_shrink(struct drm_i915_private *dev_priv,
                long target, unsigned flags)
 {
-       const bool purgeable_only = flags & I915_SHRINK_PURGEABLE;
+       const struct {
+               struct list_head *list;
+               unsigned int bit;
+       } phases[] = {
+               { &dev_priv->mm.unbound_list, I915_SHRINK_UNBOUND },
+               { &dev_priv->mm.bound_list, I915_SHRINK_BOUND },
+               { NULL, 0 },
+       }, *phase;
        unsigned long count = 0;
 
        /*
@@ -1967,48 +1974,30 @@ i915_gem_shrink(struct drm_i915_private *dev_priv,
         * dev->struct_mutex and so we won't ever be able to observe an
         * object on the bound_list with a reference count equals 0.
         */
-       if (flags & I915_SHRINK_UNBOUND) {
+       for (phase = phases; phase->list; phase++) {
                struct list_head still_in_list;
 
-               INIT_LIST_HEAD(&still_in_list);
-               while (count < target && !list_empty(&dev_priv->mm.unbound_list)) {
-                       struct drm_i915_gem_object *obj;
-
-                       obj = list_first_entry(&dev_priv->mm.unbound_list,
-                                              typeof(*obj), global_list);
-                       list_move_tail(&obj->global_list, &still_in_list);
-
-                       if (!i915_gem_object_is_purgeable(obj) && purgeable_only)
-                               continue;
-
-                       drm_gem_object_reference(&obj->base);
-
-                       if (i915_gem_object_put_pages(obj) == 0)
-                               count += obj->base.size >> PAGE_SHIFT;
-
-                       drm_gem_object_unreference(&obj->base);
-               }
-               list_splice(&still_in_list, &dev_priv->mm.unbound_list);
-       }
-
-       if (flags & I915_SHRINK_BOUND) {
-               struct list_head still_in_list;
+               if ((flags & phase->bit) == 0)
+                       continue;
 
                INIT_LIST_HEAD(&still_in_list);
-               while (count < target && !list_empty(&dev_priv->mm.bound_list)) {
+               while (count < target && !list_empty(phase->list)) {
                        struct drm_i915_gem_object *obj;
                        struct i915_vma *vma, *v;
 
-                       obj = list_first_entry(&dev_priv->mm.bound_list,
+                       obj = list_first_entry(phase->list,
                                               typeof(*obj), global_list);
                        list_move_tail(&obj->global_list, &still_in_list);
 
-                       if (!i915_gem_object_is_purgeable(obj) && purgeable_only)
+                       if (flags & I915_SHRINK_PURGEABLE &&
+                           !i915_gem_object_is_purgeable(obj))
                                continue;
 
                        drm_gem_object_reference(&obj->base);
 
-                       list_for_each_entry_safe(vma, v, &obj->vma_list, vma_link)
+                       /* For the unbound phase, this should be a no-op! */
+                       list_for_each_entry_safe(vma, v,
+                                                &obj->vma_list, vma_link)
                                if (i915_vma_unbind(vma))
                                        break;
 
@@ -2017,7 +2006,7 @@ i915_gem_shrink(struct drm_i915_private *dev_priv,
 
                        drm_gem_object_unreference(&obj->base);
                }
-               list_splice(&still_in_list, &dev_priv->mm.bound_list);
+               list_splice(&still_in_list, phase->list);
        }
 
        return count;