diff options
Diffstat (limited to 'lib/radix-tree.c')
| -rw-r--r-- | lib/radix-tree.c | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/lib/radix-tree.c b/lib/radix-tree.c index f13ddbba8ace..a1ba41730071 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -80,6 +80,8 @@ static inline void *indirect_to_ptr(void *ptr) return (void *)((unsigned long)ptr & ~RADIX_TREE_INDIRECT_PTR); } +#define RADIX_TREE_RETRY ptr_to_indirect(NULL) + #ifdef CONFIG_RADIX_TREE_MULTIORDER /* Sibling slots point directly to another slot in the same node */ static inline bool is_sibling_entry(struct radix_tree_node *parent, void *node) @@ -1443,6 +1445,14 @@ static inline void radix_tree_shrink(struct radix_tree_root *root) slot = to_free->slots[0]; if (!slot) break; + if (!radix_tree_is_indirect_ptr(slot) && (root->height > 1)) + break; + + if (radix_tree_is_indirect_ptr(slot)) { + slot = indirect_to_ptr(slot); + slot->parent = NULL; + slot = ptr_to_indirect(slot); + } /* * We don't need rcu_assign_pointer(), since we are simply @@ -1451,14 +1461,6 @@ static inline void radix_tree_shrink(struct radix_tree_root *root) * (to_free->slots[0]), it will be safe to dereference the new * one (root->rnode) as far as dependent read barriers go. */ - if (root->height > 1) { - if (!radix_tree_is_indirect_ptr(slot)) - break; - - slot = indirect_to_ptr(slot); - slot->parent = NULL; - slot = ptr_to_indirect(slot); - } root->rnode = slot; root->height--; @@ -1480,9 +1482,8 @@ static inline void radix_tree_shrink(struct radix_tree_root *root) * also results in a stale slot). So tag the slot as indirect * to force callers to retry. */ - if (root->height == 0) - *((unsigned long *)&to_free->slots[0]) |= - RADIX_TREE_INDIRECT_PTR; + if (!radix_tree_is_indirect_ptr(slot)) + to_free->slots[0] = RADIX_TREE_RETRY; radix_tree_node_free(to_free); } |