diff options
Diffstat (limited to 'include/linux/rbtree.h')
| -rw-r--r-- | include/linux/rbtree.h | 84 |
1 files changed, 47 insertions, 37 deletions
diff --git a/include/linux/rbtree.h b/include/linux/rbtree.h index fcbeed4053ef..1fd61a9af45c 100644 --- a/include/linux/rbtree.h +++ b/include/linux/rbtree.h @@ -1,20 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ /* Red Black Trees (C) 1999 Andrea Arcangeli <andrea@suse.de> - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or - (at your option) any later version. - - This program is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA linux/include/linux/rbtree.h @@ -44,25 +32,9 @@ struct rb_root { struct rb_node *rb_node; }; -/* - * Leftmost-cached rbtrees. - * - * We do not cache the rightmost node based on footprint - * size vs number of potential users that could benefit - * from O(1) rb_last(). Just not worth it, users that want - * this feature can always implement the logic explicitly. - * Furthermore, users that want to cache both pointers may - * find it a bit asymmetric, but that's ok. - */ -struct rb_root_cached { - struct rb_root rb_root; - struct rb_node *rb_leftmost; -}; - #define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3)) #define RB_ROOT (struct rb_root) { NULL, } -#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL } #define rb_entry(ptr, type, member) container_of(ptr, type, member) #define RB_EMPTY_ROOT(root) (READ_ONCE((root)->rb_node) == NULL) @@ -84,12 +56,6 @@ extern struct rb_node *rb_prev(const struct rb_node *); extern struct rb_node *rb_first(const struct rb_root *); extern struct rb_node *rb_last(const struct rb_root *); -extern void rb_insert_color_cached(struct rb_node *, - struct rb_root_cached *, bool); -extern void rb_erase_cached(struct rb_node *node, struct rb_root_cached *); -/* Same as rb_first(), but O(1) */ -#define rb_first_cached(root) (root)->rb_leftmost - /* Postorder iteration - always visit the parent after its children */ extern struct rb_node *rb_first_postorder(const struct rb_root *); extern struct rb_node *rb_next_postorder(const struct rb_node *); @@ -99,8 +65,6 @@ extern void rb_replace_node(struct rb_node *victim, struct rb_node *new, struct rb_root *root); extern void rb_replace_node_rcu(struct rb_node *victim, struct rb_node *new, struct rb_root *root); -extern void rb_replace_node_cached(struct rb_node *victim, struct rb_node *new, - struct rb_root_cached *root); static inline void rb_link_node(struct rb_node *node, struct rb_node *parent, struct rb_node **rb_link) @@ -148,4 +112,50 @@ static inline void rb_link_node_rcu(struct rb_node *node, struct rb_node *parent typeof(*pos), field); 1; }); \ pos = n) +/* + * Leftmost-cached rbtrees. + * + * We do not cache the rightmost node based on footprint + * size vs number of potential users that could benefit + * from O(1) rb_last(). Just not worth it, users that want + * this feature can always implement the logic explicitly. + * Furthermore, users that want to cache both pointers may + * find it a bit asymmetric, but that's ok. + */ +struct rb_root_cached { + struct rb_root rb_root; + struct rb_node *rb_leftmost; +}; + +#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL } + +/* Same as rb_first(), but O(1) */ +#define rb_first_cached(root) (root)->rb_leftmost + +static inline void rb_insert_color_cached(struct rb_node *node, + struct rb_root_cached *root, + bool leftmost) +{ + if (leftmost) + root->rb_leftmost = node; + rb_insert_color(node, &root->rb_root); +} + +static inline void rb_erase_cached(struct rb_node *node, + struct rb_root_cached *root) +{ + if (root->rb_leftmost == node) + root->rb_leftmost = rb_next(node); + rb_erase(node, &root->rb_root); +} + +static inline void rb_replace_node_cached(struct rb_node *victim, + struct rb_node *new, + struct rb_root_cached *root) +{ + if (root->rb_leftmost == victim) + root->rb_leftmost = new; + rb_replace_node(victim, new, &root->rb_root); +} + #endif /* _LINUX_RBTREE_H */ |