Btrfs: remove unneeded field / smaller extent_map structure
We don't need to have an unsigned int field in the extent_map struct
to tell us whether the extent map is in the inode's extent_map tree or
not. We can use the rb_node struct field and the RB_CLEAR_NODE and
RB_EMPTY_NODE macros to achieve the same task.
This reduces sizeof(struct extent_map) from 152 bytes to 144 bytes (on a
64 bits system).
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 93fba71..f0a645a 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -33,7 +33,6 @@
unsigned long flags;
struct block_device *bdev;
atomic_t refs;
- unsigned int in_tree;
unsigned int compress_type;
struct list_head list;
};
@@ -44,6 +43,11 @@
rwlock_t lock;
};
+static inline int extent_map_in_tree(const struct extent_map *em)
+{
+ return !RB_EMPTY_NODE(&em->rb_node);
+}
+
static inline u64 extent_map_end(struct extent_map *em)
{
if (em->start + em->len < em->start)