btrfs: switch extent_buffer::lock_nested to bool

The member is tracking simple status of the lock, we can use bool for
that and make some room for further space reduction in the structure.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 97d32b8..d61b526 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -4679,7 +4679,7 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start,
        rwlock_init(&eb->lock);
        atomic_set(&eb->blocking_readers, 0);
        atomic_set(&eb->blocking_writers, 0);
-       eb->lock_nested = 0;
+       eb->lock_nested = false;
        init_waitqueue_head(&eb->write_lock_wq);
        init_waitqueue_head(&eb->read_lock_wq);
 

diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 43a9530..586baed 100644 (file)
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -162,7 +162,7 @@ struct extent_buffer {
 
        atomic_t blocking_writers;
        atomic_t blocking_readers;
-       short lock_nested;
+       bool lock_nested;
        /* >= 0 if eb belongs to a log tree, -1 otherwise */
        short log_index;
 

diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index 3f7b598..6df03ba 100644 (file)
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -172,7 +172,7 @@ again:
                 * called on a partly (write-)locked tree.
                 */
                BUG_ON(eb->lock_nested);
-               eb->lock_nested = 1;
+               eb->lock_nested = true;
                read_unlock(&eb->lock);
                return;
        }
@@ -261,7 +261,7 @@ void btrfs_tree_read_unlock(struct extent_buffer *eb)
         * field only matters to the lock owner.
         */
        if (eb->lock_nested && current->pid == eb->lock_owner) {
-               eb->lock_nested = 0;
+               eb->lock_nested = false;
                return;
        }
        btrfs_assert_tree_read_locked(eb);
@@ -282,7 +282,7 @@ void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb)
         * field only matters to the lock owner.
         */
        if (eb->lock_nested && current->pid == eb->lock_owner) {
-               eb->lock_nested = 0;
+               eb->lock_nested = false;
                return;
        }
        btrfs_assert_tree_read_locked(eb);