[PATCH v2 3/4] mm/vmap: get rid of one single unlink_va() when merge

[Uladzislau Rezki (Sony)]

It does not make sense to try to "unlink" the node that is
definitely not linked with a list nor tree. On the first
merge step VA just points to the previously disconnected
busy area.

On the second step, check if the node has been merged and do
"unlink" if so, because now it points to an object that must
be linked.

Signed-off-by: Uladzislau Rezki (Sony) <urezki@xxxxxxxxx>
---
 mm/vmalloc.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index b553047aa05b..6f91136f2cc8 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -718,9 +718,6 @@ merge_or_add_vmap_area(struct vmap_area *va,
 			/* Check and update the tree if needed. */
 			augment_tree_propagate_from(sibling);
 
-			/* Remove this VA, it has been merged. */
-			unlink_va(va, root);
-
 			/* Free vmap_area object. */
 			kmem_cache_free(vmap_area_cachep, va);
 
@@ -745,12 +742,12 @@ merge_or_add_vmap_area(struct vmap_area *va,
 			/* Check and update the tree if needed. */
 			augment_tree_propagate_from(sibling);
 
-			/* Remove this VA, it has been merged. */
-			unlink_va(va, root);
+			/* Remove this VA, if it has been merged. */
+			if (merged)
+				unlink_va(va, root);
 
 			/* Free vmap_area object. */
 			kmem_cache_free(vmap_area_cachep, va);
-
 			return;
 		}
 	}
-- 
2.11.0