Provide an inlined fast path
Signed-off-by: Kent Overstreet <kent.overstr...@linux.dev>
---
include/linux/generic-radix-tree.h | 75 ++++++++++++++++++++++++++++++
lib/generic-radix-tree.c | 64 +------------------------
2 files changed, 76 insertions(+), 63 deletions(-)
diff --git a/include/linux/generic-radix-tree.h
b/include/linux/generic-radix-tree.h
index f3512fddf3d7..8a3e1e886d1c 100644
--- a/include/linux/generic-radix-tree.h
+++ b/include/linux/generic-radix-tree.h
@@ -48,6 +48,49 @@ struct genradix_root;
#define GENRADIX_NODE_SHIFT 9
#define GENRADIX_NODE_SIZE (1U << GENRADIX_NODE_SHIFT)
+#define GENRADIX_ARY (GENRADIX_NODE_SIZE / sizeof(struct
genradix_node *))
+#define GENRADIX_ARY_SHIFT ilog2(GENRADIX_ARY)
+
+/* depth that's needed for a genradix that can address up to ULONG_MAX: */
+#define GENRADIX_MAX_DEPTH \
+ DIV_ROUND_UP(BITS_PER_LONG - GENRADIX_NODE_SHIFT, GENRADIX_ARY_SHIFT)
+
+#define GENRADIX_DEPTH_MASK \
+ ((unsigned long) (roundup_pow_of_two(GENRADIX_MAX_DEPTH + 1) - 1))
+
+static inline int genradix_depth_shift(unsigned depth)
+{
+ return GENRADIX_NODE_SHIFT + GENRADIX_ARY_SHIFT * depth;
+}
+
+/*
+ * Returns size (of data, in bytes) that a tree of a given depth holds:
+ */
+static inline size_t genradix_depth_size(unsigned depth)
+{
+ return 1UL << genradix_depth_shift(depth);
+}
+
+static inline unsigned genradix_root_to_depth(struct genradix_root *r)
+{
+ return (unsigned long) r & GENRADIX_DEPTH_MASK;
+}
+
+static inline struct genradix_node *genradix_root_to_node(struct genradix_root
*r)
+{
+ return (void *) ((unsigned long) r & ~GENRADIX_DEPTH_MASK);
+}
+
+struct genradix_node {
+ union {
+ /* Interior node: */
+ struct genradix_node *children[GENRADIX_ARY];
+
+ /* Leaf: */
+ u8 data[GENRADIX_NODE_SIZE];
+ };
+};
+
struct __genradix {
struct genradix_root *root;
};
@@ -128,6 +171,30 @@ static inline size_t __idx_to_offset(size_t idx, size_t
obj_size)
#define __genradix_idx_to_offset(_radix, _idx) \
__idx_to_offset(_idx, __genradix_obj_size(_radix))
+static inline void *__genradix_ptr_inlined(struct __genradix *radix, size_t
offset)
+{
+ struct genradix_root *r = READ_ONCE(radix->root);
+ struct genradix_node *n = genradix_root_to_node(r);
+ unsigned level = genradix_root_to_depth(r);
+ unsigned shift = genradix_depth_shift(level);
+
+ if (unlikely(ilog2(offset) >= genradix_depth_shift(level)))
+ return NULL;
+
+ while (n && shift > GENRADIX_NODE_SHIFT) {
+ shift -= GENRADIX_ARY_SHIFT;
+ n = n->children[offset >> shift];
+ offset &= (1UL << shift) - 1;
+ }
+
+ return n ? &n->data[offset] : NULL;
+}
+
+#define genradix_ptr_inlined(_radix, _idx) \
+ (__genradix_cast(_radix) \
+ __genradix_ptr_inlined(&(_radix)->tree, \
+ __genradix_idx_to_offset(_radix, _idx)))
+
void *__genradix_ptr(struct __genradix *, size_t);
/**
@@ -144,6 +211,14 @@ void *__genradix_ptr(struct __genradix *, size_t);
void *__genradix_ptr_alloc(struct __genradix *, size_t, gfp_t);
+#define genradix_ptr_alloc_inlined(_radix, _idx, _gfp) \
+ (__genradix_cast(_radix) \
+ (__genradix_ptr_inlined(&(_radix)->tree, \
+ __genradix_idx_to_offset(_radix, _idx)) ?: \
+ __genradix_ptr_alloc(&(_radix)->tree, \
+ __genradix_idx_to_offset(_radix, _idx), \
+ _gfp)))
+
/**
* genradix_ptr_alloc - get a pointer to a genradix entry, allocating it
* if necessary
diff --git a/lib/generic-radix-tree.c b/lib/generic-radix-tree.c
index fa692c86f069..4efae0663049 100644
--- a/lib/generic-radix-tree.c
+++ b/lib/generic-radix-tree.c
@@ -5,75 +5,13 @@
#include <linux/gfp.h>
#include <linux/kmemleak.h>
-#define GENRADIX_ARY (GENRADIX_NODE_SIZE / sizeof(struct
genradix_node *))
-#define GENRADIX_ARY_SHIFT ilog2(GENRADIX_ARY)
-
-struct genradix_node {
- union {
- /* Interior node: */
- struct genradix_node *children[GENRADIX_ARY];
-
- /* Leaf: */
- u8 data[GENRADIX_NODE_SIZE];
- };
-};
-
-static inline int genradix_depth_shift(unsigned depth)
-{
- return GENRADIX_NODE_SHIFT + GENRADIX_ARY_SHIFT * depth;
-}
-
-/*
- * Returns size (of data, in bytes) that a tree of a given depth holds:
- */
-static inline size_t genradix_depth_size(unsigned depth)
-{
- return 1UL << genradix_depth_shift(depth);
-}
-
-/* depth that's needed for a genradix that can address up to ULONG_MAX: */
-#define GENRADIX_MAX_DEPTH \
- DIV_ROUND_UP(BITS_PER_LONG - GENRADIX_NODE_SHIFT, GENRADIX_ARY_SHIFT)
-
-#define GENRADIX_DEPTH_MASK \
- ((unsigned long) (roundup_pow_of_two(GENRADIX_MAX_DEPTH + 1) - 1))
-
-static inline unsigned genradix_root_to_depth(struct genradix_root *r)
-{
- return (unsigned long) r & GENRADIX_DEPTH_MASK;
-}
-
-static inline struct genradix_node *genradix_root_to_node(struct genradix_root
*r)
-{
- return (void *) ((unsigned long) r & ~GENRADIX_DEPTH_MASK);
-}
-
/*
* Returns pointer to the specified byte @offset within @radix, or NULL if not
* allocated
*/
void *__genradix_ptr(struct __genradix *radix, size_t offset)
{
- struct genradix_root *r = READ_ONCE(radix->root);
- struct genradix_node *n = genradix_root_to_node(r);
- unsigned level = genradix_root_to_depth(r);
-
- if (ilog2(offset) >= genradix_depth_shift(level))
- return NULL;
-
- while (1) {
- if (!n)
- return NULL;
- if (!level)
- break;
-
- level--;
-
- n = n->children[offset >> genradix_depth_shift(level)];
- offset &= genradix_depth_size(level) - 1;
- }
-
- return &n->data[offset];
+ return __genradix_ptr_inlined(radix, offset);
}
EXPORT_SYMBOL(__genradix_ptr);
--
2.45.2
