f2fs: introduce zombie list for fast shrinking extent trees

This patch removes refcount, and instead, adds zombie_list to shrink directly
without radix tree traverse.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index d81bf5a43714..e2990c978661 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -359,8 +359,8 @@ struct extent_tree {
 	struct rb_root root;		/* root of extent info rb-tree */
 	struct extent_node *cached_en;	/* recently accessed extent node */
 	struct extent_info largest;	/* largested extent info */
+	struct list_head list;		/* to be used by sbi->zombie_list */
 	rwlock_t lock;			/* protect extent info rb-tree */
-	atomic_t refcount;		/* reference count of rb-tree */
 	unsigned int count;		/* # of extent node in rb-tree*/
 };
 
@@ -764,6 +764,7 @@ struct f2fs_sb_info {
 	struct list_head extent_list;		/* lru list for shrinker */
 	spinlock_t extent_lock;			/* locking extent lru list */
 	atomic_t total_ext_tree;		/* extent tree count */
+	struct list_head zombie_list;		/* extent zombie tree list */
 	atomic_t total_zombie_tree;		/* extent zombie tree count */
 	atomic_t total_ext_node;		/* extent info count */