Commit 0070e28d authored by Matthew Wilcox's avatar Matthew Wilcox Committed by Linus Torvalds

radix_tree: loop based on shift count, not height

When we introduce entries that can cover multiple indices, we will need
to stop in __radix_tree_create based on the shift, not the height.
Split out for ease of bisect.
Signed-off-by: default avatarMatthew Wilcox <willy@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 339e6353
...@@ -415,10 +415,10 @@ int __radix_tree_create(struct radix_tree_root *root, unsigned long index, ...@@ -415,10 +415,10 @@ int __radix_tree_create(struct radix_tree_root *root, unsigned long index,
slot = indirect_to_ptr(root->rnode); slot = indirect_to_ptr(root->rnode);
height = root->height; height = root->height;
shift = (height-1) * RADIX_TREE_MAP_SHIFT; shift = height * RADIX_TREE_MAP_SHIFT;
offset = 0; /* uninitialised var warning */ offset = 0; /* uninitialised var warning */
while (height > 0) { while (shift > 0) {
if (slot == NULL) { if (slot == NULL) {
/* Have to add a child node. */ /* Have to add a child node. */
if (!(slot = radix_tree_node_alloc(root))) if (!(slot = radix_tree_node_alloc(root)))
...@@ -436,11 +436,11 @@ int __radix_tree_create(struct radix_tree_root *root, unsigned long index, ...@@ -436,11 +436,11 @@ int __radix_tree_create(struct radix_tree_root *root, unsigned long index,
} }
/* Go a level down */ /* Go a level down */
shift -= RADIX_TREE_MAP_SHIFT;
offset = (index >> shift) & RADIX_TREE_MAP_MASK; offset = (index >> shift) & RADIX_TREE_MAP_MASK;
node = slot; node = slot;
slot = node->slots[offset]; slot = node->slots[offset];
slot = indirect_to_ptr(slot); slot = indirect_to_ptr(slot);
shift -= RADIX_TREE_MAP_SHIFT;
height--; height--;
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment