Btrfs: cache extent state in find_delalloc_range
This patch makes us cache the extent state we find in find_delalloc_range since
we'll have to lock the extent later on in the function. This will keep us from
re-searching for the rang when we try to lock the extent.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 355a973..3c17c9e 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1171,7 +1171,8 @@
* 1 is returned if we find something, 0 if nothing was in the tree
*/
static noinline u64 find_delalloc_range(struct extent_io_tree *tree,
- u64 *start, u64 *end, u64 max_bytes)
+ u64 *start, u64 *end, u64 max_bytes,
+ struct extent_state **cached_state)
{
struct rb_node *node;
struct extent_state *state;
@@ -1203,8 +1204,11 @@
*end = state->end;
goto out;
}
- if (!found)
+ if (!found) {
*start = state->start;
+ *cached_state = state;
+ atomic_inc(&state->refs);
+ }
found++;
*end = state->end;
cur_start = state->end + 1;
@@ -1336,10 +1340,11 @@
delalloc_start = *start;
delalloc_end = 0;
found = find_delalloc_range(tree, &delalloc_start, &delalloc_end,
- max_bytes);
+ max_bytes, &cached_state);
if (!found || delalloc_end <= *start) {
*start = delalloc_start;
*end = delalloc_end;
+ free_extent_state(cached_state);
return found;
}