Btrfs: Add an extent buffer LRU to reduce radix tree hits
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 8409b5c..52a8b93 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -16,6 +16,7 @@
#define EXTENT_DELALLOC (1 << 5)
#define EXTENT_DEFRAG (1 << 6)
#define EXTENT_DEFRAG_DONE (1 << 7)
+#define EXTENT_BUFFER_FILLED (1 << 8)
#define EXTENT_IOBITS (EXTENT_LOCKED | EXTENT_WRITEBACK)
@@ -33,6 +34,9 @@
struct address_space *mapping;
rwlock_t lock;
struct extent_map_ops *ops;
+ spinlock_t lru_lock;
+ struct list_head buffer_lru;
+ int lru_size;
};
/* note, this must start with the same fields as fs/extent_map.c:tree_entry */
@@ -64,20 +68,17 @@
struct list_head list;
};
-#define EXTENT_INLINE_PAGES 32
struct extent_buffer {
u64 start;
unsigned long len;
- atomic_t refs;
- int flags;
- struct list_head list;
- struct list_head leak_list;
- unsigned long alloc_addr;
char *map_token;
char *kaddr;
unsigned long map_start;
unsigned long map_len;
- struct page *pages[EXTENT_INLINE_PAGES];
+ struct page *last_page;
+ struct list_head lru;
+ atomic_t refs;
+ int flags;
};
typedef struct extent_map *(get_extent_t)(struct inode *inode,
@@ -88,6 +89,7 @@
void extent_map_tree_init(struct extent_map_tree *tree,
struct address_space *mapping, gfp_t mask);
+void extent_map_tree_cleanup(struct extent_map_tree *tree);
struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
u64 start, u64 end);
int add_extent_mapping(struct extent_map_tree *tree,