UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

radix_tree: clean away saw_unset_tag leftovers 

radix_tree_tag_get()'s BUG (when it sees a tag after saw_unset_tag) was
unsafe and removed in 2.6.34, but the pointless saw_unset_tag left behind.

Remove it now, and return 0 as soon as we see unset tag - we already rely
upon the root tag to be correct, returning 0 immediately if it's not set.

Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Hugh Dickins 2011-10-31 17:07:02 -07:00 committed by Linus Torvalds
parent 0dabec93de
commit 3fa36acbce
1 changed files with 2 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
lib/radix-tree.c
View File

@ -576,7 +576,6 @@ int radix_tree_tag_get(struct radix_tree_root *root,
{
unsigned int height, shift;
struct radix_tree_node *node;
int saw_unset_tag = 0;
/* check the root's tag bit */
if (!root_tag_get(root, tag))
@ -603,15 +602,10 @@ int radix_tree_tag_get(struct radix_tree_root *root,
return 0;
offset = (index >> shift) & RADIX_TREE_MAP_MASK;
/*
* This is just a debug check. Later, we can bale as soon as
* we see an unset tag.
*/
if (!tag_get(node, tag, offset))
saw_unset_tag = 1;
return 0;
if (height == 1)
return !!tag_get(node, tag, offset);
return 1;
node = rcu_dereference_raw(node->slots[offset]);
shift -= RADIX_TREE_MAP_SHIFT;
height--;