drm/i915: use the new iterator in i915_gem_busy_ioctl v2

This makes the function much simpler since the complex
retry logic is now handled else where.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20211116102431.198905-2-christian.koenig@amd.com

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_busy.c b/drivers/gpu/drm/i915/gem/i915_gem_busy.c
index 7358beb..470fdfd 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_busy.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_busy.c
@@ -115,8 +115,8 @@ i915_gem_busy_ioctl(struct drm_device *dev, void *data,
 {
        struct drm_i915_gem_busy *args = data;
        struct drm_i915_gem_object *obj;
-       struct dma_resv_list *list;
-       unsigned int seq;
+       struct dma_resv_iter cursor;
+       struct dma_fence *fence;
        int err;
 
        err = -ENOENT;
@@ -142,27 +142,20 @@ i915_gem_busy_ioctl(struct drm_device *dev, void *data,
         * to report the overall busyness. This is what the wait-ioctl does.
         *
         */
-retry:
-       seq = raw_read_seqcount(&obj->base.resv->seq);
-
-       /* Translate the exclusive fence to the READ *and* WRITE engine */
-       args->busy = busy_check_writer(dma_resv_excl_fence(obj->base.resv));
-
-       /* Translate shared fences to READ set of engines */
-       list = dma_resv_shared_list(obj->base.resv);
-       if (list) {
-               unsigned int shared_count = list->shared_count, i;
-
-               for (i = 0; i < shared_count; ++i) {
-                       struct dma_fence *fence =
-                               rcu_dereference(list->shared[i]);
-
+       args->busy = 0;
+       dma_resv_iter_begin(&cursor, obj->base.resv, true);
+       dma_resv_for_each_fence_unlocked(&cursor, fence) {
+               if (dma_resv_iter_is_restarted(&cursor))
+                       args->busy = 0;
+
+               if (dma_resv_iter_is_exclusive(&cursor))
+                       /* Translate the exclusive fence to the READ *and* WRITE engine */
+                       args->busy |= busy_check_writer(fence);
+               else
+                       /* Translate shared fences to READ set of engines */
                        args->busy |= busy_check_reader(fence);
-               }
        }
-
-       if (args->busy && read_seqcount_retry(&obj->base.resv->seq, seq))
-               goto retry;
+       dma_resv_iter_end(&cursor);
 
        err = 0;
 out: