[PATCH v2 4/5] mm/vmalloc.c: Modify function merge_or_add_vmap_area() for readability

[Pengfei Li]

Since function merge_or_add_vmap_area() is only used to
merge or add vmap area to the *FREE* tree, so rename it
to merge_or_add_va_to_free_tree.

Then this is obvious, merge_or_add_vmap_area() does not
need parameters root and head, so remove them.

Signed-off-by: Pengfei Li <lpf.vec...@gmail.com>
---
 mm/vmalloc.c | 21 +++++++++------------
 1 file changed, 9 insertions(+), 12 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index b6ea52d6e8f9..ad117d16af34 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -688,8 +688,7 @@ insert_va_to_free_tree(struct vmap_area *va, struct rb_node 
*from)
  * freed.
  */
 static __always_inline void
-merge_or_add_vmap_area(struct vmap_area *va,
-       struct rb_root *root, struct list_head *head)
+merge_or_add_va_to_free_tree(struct vmap_area *va)
 {
        struct vmap_area *sibling;
        struct list_head *next;
@@ -701,7 +700,7 @@ merge_or_add_vmap_area(struct vmap_area *va,
         * Find a place in the tree where VA potentially will be
         * inserted, unless it is merged with its sibling/siblings.
         */
-       link = find_va_links(va, root, NULL, &parent);
+       link = find_va_links(va, &free_vmap_area_root, NULL, &parent);
 
        /*
         * Get next node of VA to check if merging can be done.
@@ -717,7 +716,7 @@ merge_or_add_vmap_area(struct vmap_area *va,
         *                  |                |
         *                  start            end
         */
-       if (next != head) {
+       if (next != &free_vmap_area_list) {
                sibling = list_entry(next, struct vmap_area, list);
                if (sibling->va_start == va->va_end) {
                        sibling->va_start = va->va_start;
@@ -725,9 +724,6 @@ 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);
 
@@ -744,7 +740,7 @@ merge_or_add_vmap_area(struct vmap_area *va,
         *                  |                |
         *                  start            end
         */
-       if (next->prev != head) {
+       if (next->prev != &free_vmap_area_list) {
                sibling = list_entry(next->prev, struct vmap_area, list);
                if (sibling->va_end == va->va_start) {
                        sibling->va_end = va->va_end;
@@ -753,7 +749,8 @@ merge_or_add_vmap_area(struct vmap_area *va,
                        augment_tree_propagate_from(sibling);
 
                        /* Remove this VA, it has been merged. */
-                       unlink_va(va, root);
+                       if (merged)
+                               unlink_va(va, &free_vmap_area_root);
 
                        /* Free vmap_area object. */
                        kmem_cache_free(vmap_area_cachep, va);
@@ -764,7 +761,8 @@ merge_or_add_vmap_area(struct vmap_area *va,
 
 insert:
        if (!merged) {
-               link_va(va, root, parent, link, head);
+               link_va(va, &free_vmap_area_root, parent, link,
+                       &free_vmap_area_list);
                augment_tree_propagate_from(va);
        }
 }
@@ -1141,8 +1139,7 @@ static void __free_vmap_area(struct vmap_area *va)
        /*
         * Merge VA with its neighbors, otherwise just add it.
         */
-       merge_or_add_vmap_area(va,
-               &free_vmap_area_root, &free_vmap_area_list);
+       merge_or_add_va_to_free_tree(va);
 }
 
 /*
-- 
2.21.0