Btrfs: Add btree locking to the tree defragmentation code
The online btree defragger is simplified and rewritten to use
standard btree searches instead of a walk up / down mechanism.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 89cc4f6..a9b3a25 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2201,6 +2201,7 @@
{
mutex_unlock(&root->fs_info->alloc_mutex);
lookup_extent_ref(NULL, root, start, len, refs);
+ cond_resched();
mutex_lock(&root->fs_info->alloc_mutex);
return lookup_extent_ref(NULL, root, start, len, refs);
}
@@ -2280,6 +2281,7 @@
next = read_tree_block(root, bytenr, blocksize,
ptr_gen);
+ cond_resched();
mutex_lock(&root->fs_info->alloc_mutex);
/* we've dropped the lock, double check */
@@ -2329,6 +2331,7 @@
*level += 1;
BUG_ON(ret);
mutex_unlock(&root->fs_info->alloc_mutex);
+ cond_resched();
return 0;
}
@@ -2448,6 +2451,10 @@
break;
if (wret < 0)
ret = wret;
+ if (trans->transaction->in_commit) {
+ ret = -EAGAIN;
+ break;
+ }
}
for (i = 0; i <= orig_level; i++) {
if (path->nodes[i]) {