aboutsummaryrefslogtreecommitdiffstats
path: root/fs/btrfs/free-space-cache.c
diff options
context:
space:
mode:
authorMiao Xie <miaox@cn.fujitsu.com>2012-10-18 08:18:01 +0000
committerJosef Bacik <jbacik@fusionio.com>2012-12-11 13:31:33 -0500
commitde6c4115a297d4bbf178aca9948c3539f89c9caa (patch)
tree673e3a6f97931dbed42b0dc8fca2e2a44c3808cc /fs/btrfs/free-space-cache.c
parentde1ee92ac3bce4c9d760016c4d6198158e6e2f15 (diff)
Btrfs: fix unnecessary while loop when search the free space, cache
When we find a bitmap free space entry, we may check the previous extent entry covers the offset or not. But if we find this entry is also a bitmap entry, we will continue to check the previous entry of the current one by a while loop. It is unnecessary because it is impossible that the extent entry which is in front of a bitmap entry can cover the offset of the entry after that bitmap entry. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Diffstat (limited to 'fs/btrfs/free-space-cache.c')
-rw-r--r--fs/btrfs/free-space-cache.c30
1 files changed, 10 insertions, 20 deletions
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 1027b854b90..557502ca1a2 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -1250,18 +1250,13 @@ tree_search_offset(struct btrfs_free_space_ctl *ctl,
* if previous extent entry covers the offset,
* we should return it instead of the bitmap entry
*/
- n = &entry->offset_index;
- while (1) {
- n = rb_prev(n);
- if (!n)
- break;
+ n = rb_prev(&entry->offset_index);
+ if (n) {
prev = rb_entry(n, struct btrfs_free_space,
offset_index);
- if (!prev->bitmap) {
- if (prev->offset + prev->bytes > offset)
- entry = prev;
- break;
- }
+ if (!prev->bitmap &&
+ prev->offset + prev->bytes > offset)
+ entry = prev;
}
}
return entry;
@@ -1287,18 +1282,13 @@ tree_search_offset(struct btrfs_free_space_ctl *ctl,
}
if (entry->bitmap) {
- n = &entry->offset_index;
- while (1) {
- n = rb_prev(n);
- if (!n)
- break;
+ n = rb_prev(&entry->offset_index);
+ if (n) {
prev = rb_entry(n, struct btrfs_free_space,
offset_index);
- if (!prev->bitmap) {
- if (prev->offset + prev->bytes > offset)
- return prev;
- break;
- }
+ if (!prev->bitmap &&
+ prev->offset + prev->bytes > offset)
+ return prev;
}
if (entry->offset + BITS_PER_BITMAP * ctl->unit > offset)
return entry;