[PATCH] btrfs: Refactor count handling in btrfs_unpin_free_ino()

From: Geert Uytterhoeven
Date: Sat Jul 15 2017 - 07:00:15 EST


With gcc 4.1.2:

fs/btrfs/inode-map.c: In function âbtrfs_unpin_free_inoâ:
fs/btrfs/inode-map.c:254: warning: âcountâ may be used uninitialized in this function

While this warning is a false-positive, it can easily be killed by
refactoring the code.

Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
Please review. Compile-tested only.
---
fs/btrfs/inode-map.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index d02019747d001d7b..5d98ac9a2a665bd4 100644
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -257,8 +257,6 @@ void btrfs_unpin_free_ino(struct btrfs_root *root)
return;

while (1) {
- bool add_to_ctl = true;
-
spin_lock(rbroot_lock);
n = rb_first(rbroot);
if (!n) {
@@ -270,15 +268,14 @@ void btrfs_unpin_free_ino(struct btrfs_root *root)
BUG_ON(info->bitmap); /* Logic error */

if (info->offset > root->ino_cache_progress)
- add_to_ctl = false;
- else if (info->offset + info->bytes > root->ino_cache_progress)
- count = root->ino_cache_progress - info->offset + 1;
+ count = 0;
else
- count = info->bytes;
+ count = min(root->ino_cache_progress - info->offset + 1,
+ info->bytes);

rb_erase(&info->offset_index, rbroot);
spin_unlock(rbroot_lock);
- if (add_to_ctl)
+ if (count)
__btrfs_add_free_space(root->fs_info, ctl,
info->offset, count);
kmem_cache_free(btrfs_free_space_cachep, info);
--
2.7.4