Btrfs: rework ulist with list+rb_tree

[cascardo/linux.git] / fs / btrfs / ulist.h

diff --git a/fs/btrfs/ulist.h b/fs/btrfs/ulist.h
index fb36731..2be7102 100644 (file)
--- a/fs/btrfs/ulist.h
+++ b/fs/btrfs/ulist.h
@@ -17,18 +17,12 @@
  * enumerating it.
  * It is possible to store an auxiliary value along with the key.
  *
- * The implementation is preliminary and can probably be sped up
- * significantly. A first step would be to store the values in an rbtree
- * as soon as ULIST_SIZE is exceeded.
  */
-
-/*
- * number of elements statically allocated inside struct ulist
- */
-#define ULIST_SIZE 16
-
 struct ulist_iterator {
+#ifdef CONFIG_BTRFS_DEBUG
        int i;
+#endif
+       struct list_head *cur_list;  /* hint to start search */
 };
 
 /*
@@ -37,6 +31,12 @@ struct ulist_iterator {
 struct ulist_node {
        u64 val;                /* value to store */
        u64 aux;                /* auxiliary value saved along with the val */
+
+#ifdef CONFIG_BTRFS_DEBUG
+       int seqnum;             /* sequence number this node is added */
+#endif
+
+       struct list_head list;  /* used to link node */
        struct rb_node rb_node; /* used to speed up search */
 };
 
@@ -46,24 +46,8 @@ struct ulist {
         */
        unsigned long nnodes;
 
-       /*
-        * number of nodes we already have room for
-        */
-       unsigned long nodes_alloced;
-
-       /*
-        * pointer to the array storing the elements. The first ULIST_SIZE
-        * elements are stored inline. In this case the it points to int_nodes.
-        * After exceeding ULIST_SIZE, dynamic memory is allocated.
-        */
-       struct ulist_node *nodes;
-
+       struct list_head nodes;
        struct rb_root root;
-
-       /*
-        * inline storage space for the first ULIST_SIZE entries
-        */
-       struct ulist_node int_nodes[ULIST_SIZE];
 };
 
 void ulist_init(struct ulist *ulist);
@@ -77,6 +61,6 @@ int ulist_add_merge(struct ulist *ulist, u64 val, u64 aux,
 struct ulist_node *ulist_next(struct ulist *ulist,
                              struct ulist_iterator *uiter);
 
-#define ULIST_ITER_INIT(uiter) ((uiter)->i = 0)
+#define ULIST_ITER_INIT(uiter) ((uiter)->cur_list = NULL)
 
 #endif