Btrfs: Add readahead to the online shrinker, and a mount -o alloc_start= for testing
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index a421069..d6243c2 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1630,11 +1630,11 @@
struct btrfs_path *path;
btrfs_set_stack_extent_refs(&extent_item, 1);
-#if 0
- new_hint = max(hint_byte, 16ULL * 1024 * 1024 * 1024);
+
+ new_hint = max(hint_byte, root->fs_info->alloc_start);
if (new_hint < btrfs_super_total_bytes(&info->super_copy))
hint_byte = new_hint;
-#endif
+
WARN_ON(num_bytes < root->sectorsize);
ret = find_free_extent(trans, root, num_bytes, empty_size,
search_start, search_end, hint_byte, ins,
@@ -2239,7 +2239,7 @@
free_extent_buffer(eb);
path->lowest_level = level;
- path->reada = 0;
+ path->reada = 2;
ret = btrfs_search_slot(trans, found_root, &found_key, path,
0, 1);
path->lowest_level = 0;
@@ -2372,6 +2372,7 @@
block_group_cache = &info->block_group_cache;
path = btrfs_alloc_path();
root = root->fs_info->extent_root;
+ path->reada = 2;
again:
total_found = 0;