Btrfs: Optimize tree log block allocations
Since tree log blocks get freed every transaction, they never really
need to be written to disk. This skips the step where we update
metadata to record they were allocated.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 7c06eb4..5edb7f8 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -829,9 +829,8 @@
WARN_ON(btrfs_header_level(eb) != 0);
WARN_ON(btrfs_header_nritems(eb) != 0);
- ret = btrfs_free_extent(trans, fs_info->tree_root,
- eb->start, eb->len,
- BTRFS_TREE_LOG_OBJECTID, 0, 0, 0, 1);
+ ret = btrfs_free_reserved_extent(fs_info->tree_root,
+ eb->start, eb->len);
BUG_ON(ret);
free_extent_buffer(eb);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 3181759..c479d71 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1872,8 +1872,15 @@
return 0;
}
/* if metadata always pin */
- if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID)
+ if (owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
+ if (root->root_key.objectid == BTRFS_TREE_LOG_OBJECTID) {
+ /* btrfs_free_reserved_extent */
+ set_extent_dirty(&root->fs_info->free_space_cache,
+ bytenr, bytenr + num_bytes - 1, GFP_NOFS);
+ return 0;
+ }
pin = 1;
+ }
/* if data pin when any transaction has committed this */
if (ref_generation != trans->transid)
@@ -2361,11 +2368,13 @@
min_alloc_size, empty_size, hint_byte,
search_end, ins, data);
BUG_ON(ret);
- ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid,
- ref_generation, owner,
- owner_offset, ins);
- BUG_ON(ret);
+ if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
+ ret = __btrfs_alloc_reserved_extent(trans, root, root_objectid,
+ ref_generation, owner,
+ owner_offset, ins);
+ BUG_ON(ret);
+ }
maybe_unlock_mutex(root);
return ret;
}
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index f43ee33..5f77bee 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -1728,9 +1728,8 @@
WARN_ON(root_owner !=
BTRFS_TREE_LOG_OBJECTID);
- ret = btrfs_free_extent(trans, root, bytenr,
- blocksize, root_owner,
- root_gen, 0, 0, 1);
+ ret = btrfs_free_reserved_extent(root,
+ bytenr, blocksize);
BUG_ON(ret);
}
free_extent_buffer(next);
@@ -1775,8 +1774,7 @@
BUG_ON(ret);
}
WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
- ret = btrfs_free_extent(trans, root, bytenr, blocksize,
- root_owner, root_gen, 0, 0, 1);
+ ret = btrfs_free_reserved_extent(root, bytenr, blocksize);
BUG_ON(ret);
}
free_extent_buffer(path->nodes[*level]);
@@ -1837,10 +1835,9 @@
}
WARN_ON(root_owner != BTRFS_TREE_LOG_OBJECTID);
- ret = btrfs_free_extent(trans, root,
+ ret = btrfs_free_reserved_extent(root,
path->nodes[*level]->start,
- path->nodes[*level]->len,
- root_owner, root_gen, 0, 0, 1);
+ path->nodes[*level]->len);
BUG_ON(ret);
}
free_extent_buffer(path->nodes[*level]);
@@ -1910,11 +1907,8 @@
}
WARN_ON(log->root_key.objectid !=
BTRFS_TREE_LOG_OBJECTID);
- ret = btrfs_free_extent(trans, log,
- next->start, next->len,
- log->root_key.objectid,
- btrfs_header_generation(next),
- 0, 0, 1);
+ ret = btrfs_free_reserved_extent(log, next->start,
+ next->len);
BUG_ON(ret);
}
}
