drm/i915: Introduce accurate frontbuffer tracking

[deliverable/linux.git] / drivers / gpu / drm / i915 / i915_gem.c

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 903f8f5bf761ac922b8d8a9e6021460ad87a7394..caed6621d71a0e6219297906197166c445616256 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4452,6 +4452,8 @@ void i915_gem_free_object(struct drm_gem_object *gem_obj)
        if (obj->stolen)
                i915_gem_object_unpin_pages(obj);
 
+       WARN_ON(obj->frontbuffer_bits);
+
        if (WARN_ON(obj->pages_pin_count))
                obj->pages_pin_count = 0;
        if (discard_backing_storage(obj))
@@ -4996,6 +4998,23 @@ int i915_gem_open(struct drm_device *dev, struct drm_file *file)
        return ret;
 }
 
+void i915_gem_track_fb(struct drm_i915_gem_object *old,
+                      struct drm_i915_gem_object *new,
+                      unsigned frontbuffer_bits)
+{
+       if (old) {
+               WARN_ON(!mutex_is_locked(&old->base.dev->struct_mutex));
+               WARN_ON(!(old->frontbuffer_bits & frontbuffer_bits));
+               old->frontbuffer_bits &= ~frontbuffer_bits;
+       }
+
+       if (new) {
+               WARN_ON(!mutex_is_locked(&new->base.dev->struct_mutex));
+               WARN_ON(new->frontbuffer_bits & frontbuffer_bits);
+               new->frontbuffer_bits |= frontbuffer_bits;
+       }
+}
+
 static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task)
 {
        if (!mutex_is_locked(mutex))