diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index 2afbd69ab9f0..6cb7c883fad0 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -312,6 +312,56 @@ static int sync_fence_copy_pts(struct sync_fence *dst, struct sync_fence *src) return 0; } +static int sync_fence_merge_pts(struct sync_fence *dst, struct sync_fence *src) +{ + struct list_head *src_pos, *dst_pos, *n; + + list_for_each(src_pos, &src->pt_list_head) { + struct sync_pt *src_pt = + container_of(src_pos, struct sync_pt, pt_list); + bool collapsed = false; + + list_for_each_safe(dst_pos, n, &dst->pt_list_head) { + struct sync_pt *dst_pt = + container_of(dst_pos, struct sync_pt, pt_list); + /* collapse two sync_pts on the same timeline + * to a single sync_pt that will signal at + * the later of the two + */ + if (dst_pt->parent == src_pt->parent) { + if (dst_pt->parent->ops->compare(dst_pt, src_pt) + == -1) { + struct sync_pt *new_pt = + sync_pt_dup(src_pt); + if (new_pt == NULL) + return -ENOMEM; + + new_pt->fence = dst; + list_replace(&dst_pt->pt_list, + &new_pt->pt_list); + sync_pt_activate(new_pt); + sync_pt_free(dst_pt); + } + collapsed = true; + break; + } + } + + if (!collapsed) { + struct sync_pt *new_pt = sync_pt_dup(src_pt); + + if (new_pt == NULL) + return -ENOMEM; + + new_pt->fence = dst; + list_add(&new_pt->pt_list, &dst->pt_list_head); + sync_pt_activate(new_pt); + } + } + + return 0; +} + static void sync_fence_free_pts(struct sync_fence *fence) { struct list_head *pos, *n; @@ -386,7 +436,7 @@ struct sync_fence *sync_fence_merge(const char *name, if (err < 0) goto err; - err = sync_fence_copy_pts(fence, b); + err = sync_fence_merge_pts(fence, b); if (err < 0) goto err;