diff --git a/src/util/u_gralloc/u_gralloc.c b/src/util/u_gralloc/u_gralloc.c
index 0d1e5f6f62b..0adc58e8626 100644
--- a/src/util/u_gralloc/u_gralloc.c
+++ b/src/util/u_gralloc/u_gralloc.c
@@ -23,6 +23,7 @@ static const struct u_grallocs {
    enum u_gralloc_type type;
    struct u_gralloc *(*create)();
 } u_grallocs[] = {
+   /* Prefer the CrOS API as it is significantly faster than IMapper4 */
    {.type = U_GRALLOC_TYPE_CROS, .create = u_gralloc_cros_api_create},
 #ifdef USE_IMAPPER4_METADATA_API
    {.type = U_GRALLOC_TYPE_GRALLOC4, .create = u_gralloc_imapper_api_create},