The patch titled
radixtree: introduce __radix_tree_lookup_parent()
has been added to the -mm tree. Its filename is
radixtree-introduce-__radix_tree_lookup_parent.patch
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: radixtree: introduce __radix_tree_lookup_parent()
From: Wu Fengguang <wfg@xxxxxxxxxxxxxxxx>
Introduce a general lookup function to radix tree.
- __radix_tree_lookup_parent(root, index, level)
Perform partial lookup, return the @level'th parent of the slot at
@index.
Signed-off-by: Wu Fengguang <wfg@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
include/linux/radix-tree.h | 16 +++++++++
lib/radix-tree.c | 58 +++++++++++++++++------------------
2 files changed, 44 insertions(+), 30 deletions(-)
diff -puN include/linux/radix-tree.h~radixtree-introduce-__radix_tree_lookup_parent include/linux/radix-tree.h
--- 25/include/linux/radix-tree.h~radixtree-introduce-__radix_tree_lookup_parent Fri May 26 13:33:44 2006
+++ 25-akpm/include/linux/radix-tree.h Fri May 26 13:33:44 2006
@@ -49,7 +49,8 @@ do { \
} while (0)
int radix_tree_insert(struct radix_tree_root *, unsigned long, void *);
-void *radix_tree_lookup(struct radix_tree_root *, unsigned long);
+void *__radix_tree_lookup_parent(struct radix_tree_root *,
+ unsigned long, unsigned int);
void **radix_tree_lookup_slot(struct radix_tree_root *, unsigned long);
void *radix_tree_delete(struct radix_tree_root *, unsigned long);
unsigned int
@@ -74,4 +75,17 @@ static inline void radix_tree_preload_en
preempt_enable();
}
+/**
+ * radix_tree_lookup - perform lookup operation on a radix tree
+ * @root: radix tree root
+ * @index: index key
+ *
+ * Lookup the item at the position @index in the radix tree @root.
+ */
+static inline void *radix_tree_lookup(struct radix_tree_root *root,
+ unsigned long index)
+{
+ return __radix_tree_lookup_parent(root, index, 0);
+}
+
#endif /* _LINUX_RADIX_TREE_H */
diff -puN lib/radix-tree.c~radixtree-introduce-__radix_tree_lookup_parent lib/radix-tree.c
--- 25/lib/radix-tree.c~radixtree-introduce-__radix_tree_lookup_parent Fri May 26 13:33:44 2006
+++ 25-akpm/lib/radix-tree.c Fri May 26 13:33:44 2006
@@ -308,36 +308,46 @@ int radix_tree_insert(struct radix_tree_
}
EXPORT_SYMBOL(radix_tree_insert);
-static inline void **__lookup_slot(struct radix_tree_root *root,
- unsigned long index)
+/**
+ * __radix_tree_lookup_parent - low level lookup routine
+ * @root: radix tree root
+ * @index: index key
+ * @level: stop at that many levels from the tree leaf
+ *
+ * Lookup the @level'th parent of the slot at @index in radix tree @root.
+ * The return value is:
+ * @level == 0: page at @index;
+ * @level == 1: the corresponding bottom level tree node;
+ * @level < height: (@level-1)th parent node of the bottom node
+ * that contains @index;
+ * @level >= height: the root node.
+ */
+void *__radix_tree_lookup_parent(struct radix_tree_root *root,
+ unsigned long index, unsigned int level)
{
unsigned int height, shift;
- struct radix_tree_node **slot;
+ struct radix_tree_node *slot;
height = root->height;
if (index > radix_tree_maxindex(height))
return NULL;
- if (height == 0 && root->rnode)
- return (void **)&root->rnode;
-
shift = (height-1) * RADIX_TREE_MAP_SHIFT;
- slot = &root->rnode;
+ slot = root->rnode;
- while (height > 0) {
- if (*slot == NULL)
+ while (height > level) {
+ if (slot == NULL)
return NULL;
- slot = (struct radix_tree_node **)
- ((*slot)->slots +
- ((index >> shift) & RADIX_TREE_MAP_MASK));
+ slot = slot->slots[(index >> shift) & RADIX_TREE_MAP_MASK];
shift -= RADIX_TREE_MAP_SHIFT;
height--;
}
- return (void **)slot;
+ return slot;
}
+EXPORT_SYMBOL(__radix_tree_lookup_parent);
/**
* radix_tree_lookup_slot - lookup a slot in a radix tree
@@ -349,25 +359,15 @@ static inline void **__lookup_slot(struc
*/
void **radix_tree_lookup_slot(struct radix_tree_root *root, unsigned long index)
{
- return __lookup_slot(root, index);
-}
-EXPORT_SYMBOL(radix_tree_lookup_slot);
+ struct radix_tree_node *node;
-/**
- * radix_tree_lookup - perform lookup operation on a radix tree
- * @root: radix tree root
- * @index: index key
- *
- * Lookup the item at the position @index in the radix tree @root.
- */
-void *radix_tree_lookup(struct radix_tree_root *root, unsigned long index)
-{
- void **slot;
+ if (root->height == 0)
+ return &root->rnode;
- slot = __lookup_slot(root, index);
- return slot != NULL ? *slot : NULL;
+ node = __radix_tree_lookup_parent(root, index, 1);
+ return node ? node->slots + (index & RADIX_TREE_MAP_MASK) : NULL;
}
-EXPORT_SYMBOL(radix_tree_lookup);
+EXPORT_SYMBOL(radix_tree_lookup_slot);
/**
* radix_tree_tag_set - set a tag on a radix tree node
_
Patches currently in -mm which might be from wfg@xxxxxxxxxxxxxxxx are
readahead-kconfig-options.patch
radixtree-introduce-__radix_tree_lookup_parent.patch
radixtree-introduce-radix_tree_scan_hole.patch
mm-introduce-probe_pages.patch
mm-introduce-pg_readahead.patch
readahead-add-look-ahead-support-to-__do_page_cache_readahead.patch
readahead-delay-page-release-in-do_generic_mapping_read.patch
readahead-insert-cond_resched-calls.patch
readahead-minmax_ra_pages.patch
readahead-events-accounting.patch
readahead-rescue_pages.patch
readahead-sysctl-parameters.patch
readahead-min-max-sizes.patch
readahead-state-based-method-aging-accounting.patch
readahead-state-based-method-routines.patch
readahead-state-based-method.patch
readahead-context-based-method.patch
readahead-initial-method-guiding-sizes.patch
readahead-initial-method-thrashing-guard-size.patch
readahead-initial-method-expected-read-size.patch
readahead-initial-method-user-recommended-size.patch
readahead-initial-method.patch
readahead-backward-prefetching-method.patch
readahead-seeking-reads-method.patch
readahead-thrashing-recovery-method.patch
readahead-call-scheme.patch
readahead-laptop-mode.patch
readahead-loop-case.patch
readahead-nfsd-case.patch
readahead-turn-on-by-default.patch
readahead-debug-radix-tree-new-functions.patch
readahead-debug-traces-showing-accessed-file-names.patch
readahead-debug-traces-showing-read-patterns.patch
-
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