lib/prio_tree.h

   1 #ifndef _LINUX_PRIO_TREE_H
   2 #define _LINUX_PRIO_TREE_H
   3
   4 #include <inttypes.h>
   5
   6 struct prio_tree_node {
   7         struct prio_tree_node   *left;
   8         struct prio_tree_node   *right;
   9         struct prio_tree_node   *parent;
  10         uint64_t                start;
  11         uint64_t                last;   /* last location _in_ interval */
  12 };
  13
  14 struct prio_tree_root {
  15         struct prio_tree_node   *prio_tree_node;
  16         unsigned short          index_bits;
  17 };
  18
  19 struct prio_tree_iter {
  20         struct prio_tree_node   *cur;
  21         unsigned long           mask;
  22         unsigned long           value;
  23         int                     size_level;
  24
  25         struct prio_tree_root   *root;
  26         uint64_t                r_index;
  27         uint64_t                h_index;
  28 };
  29
  30 static inline void prio_tree_iter_init(struct prio_tree_iter *iter,
  31                 struct prio_tree_root *root, uint64_t r_index, uint64_t h_index)
  32 {
  33         iter->root = root;
  34         iter->r_index = r_index;
  35         iter->h_index = h_index;
  36         iter->cur = NULL;
  37 }
  38
  39 #define INIT_PRIO_TREE_ROOT(ptr)        \
  40 do {                                    \
  41         (ptr)->prio_tree_node = NULL;   \
  42         (ptr)->index_bits = 1;          \
  43 } while (0)
  44
  45 #define INIT_PRIO_TREE_NODE(ptr)                                \
  46 do {                                                            \
  47         (ptr)->left = (ptr)->right = (ptr)->parent = (ptr);     \
  48 } while (0)
  49
  50 #define INIT_PRIO_TREE_ITER(ptr)        \
  51 do {                                    \
  52         (ptr)->cur = NULL;              \
  53         (ptr)->mask = 0UL;              \
  54         (ptr)->value = 0UL;             \
  55         (ptr)->size_level = 0;          \
  56 } while (0)
  57
  58 #define prio_tree_entry(ptr, type, member) \
  59        ((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
  60
  61 static inline int prio_tree_empty(const struct prio_tree_root *root)
  62 {
  63         return root->prio_tree_node == NULL;
  64 }
  65
  66 static inline int prio_tree_root(const struct prio_tree_node *node)
  67 {
  68         return node->parent == node;
  69 }
  70
  71 static inline int prio_tree_left_empty(const struct prio_tree_node *node)
  72 {
  73         return node->left == node;
  74 }
  75
  76 static inline int prio_tree_right_empty(const struct prio_tree_node *node)
  77 {
  78         return node->right == node;
  79 }
  80
  81
  82 struct prio_tree_node *prio_tree_replace(struct prio_tree_root *root,
  83                 struct prio_tree_node *old, struct prio_tree_node *node);
  84 struct prio_tree_node *prio_tree_insert(struct prio_tree_root *root,
  85                 struct prio_tree_node *node);
  86 void prio_tree_remove(struct prio_tree_root *root, struct prio_tree_node *node);
  87 struct prio_tree_node *prio_tree_next(struct prio_tree_iter *iter);
  88
  89 #endif /* _LINUX_PRIO_TREE_H */