[PATCH 13/13] lib/generic-radix-tree: Simplify __genradix_ptr()

From: David Laight
Date: Tue Aug 25 2020 - 10:54:16 EST


Now that requests for small trees are inlined there is no need
to aggressively optimise for them in __genradix_ptr().

Signed-off-by: David Laight <david.laight@xxxxxxxxxx>
---
lib/generic-radix-tree.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/lib/generic-radix-tree.c b/lib/generic-radix-tree.c
index 7029a14eed97..497ac5effda0 100644
--- a/lib/generic-radix-tree.c
+++ b/lib/generic-radix-tree.c
@@ -45,9 +45,6 @@ void *__genradix_ptr(struct genradix_root *r, size_t offset)
unsigned int shift = __genradix_root_to_shift(r);
unsigned int idx;

- if (likely(shift == GENRADIX_ROOT_SHIFT))
- return offset < PAGE_SIZE ? n->data + offset : NULL;
-
if (unlikely(!shift))
return NULL;

@@ -56,13 +53,13 @@ void *__genradix_ptr(struct genradix_root *r, size_t offset)
return NULL;

for (;;) {
+ if (likely(shift == GENRADIX_ROOT_SHIFT))
+ return n->data + (offset % PAGE_SIZE);
+
n = READ_ONCE(n->children[idx]);
if (unlikely(!n))
return NULL;

- if (shift == PAGE_SHIFT)
- return n->data + (offset % PAGE_SIZE);
-
shift -= GENRADIX_ARY_SHIFT;
idx = (offset >> shift) % GENRADIX_ARY;
}
--
2.25.1

-
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