| .. | .. | 
|---|
|  | 1 | +/* SPDX-License-Identifier: GPL-2.0-or-later */ | 
|---|
| 1 | 2 | /* | 
|---|
| 2 | 3 | Red Black Trees | 
|---|
| 3 | 4 | (C) 1999  Andrea Arcangeli <andrea@suse.de> | 
|---|
| 4 | 5 |  | 
|---|
| 5 |  | -  This program is free software; you can redistribute it and/or modify | 
|---|
| 6 |  | -  it under the terms of the GNU General Public License as published by | 
|---|
| 7 |  | -  the Free Software Foundation; either version 2 of the License, or | 
|---|
| 8 |  | -  (at your option) any later version. | 
|---|
| 9 |  | - | 
|---|
| 10 |  | -  This program is distributed in the hope that it will be useful, | 
|---|
| 11 |  | -  but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|---|
| 12 |  | -  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
|---|
| 13 |  | -  GNU General Public License for more details. | 
|---|
| 14 |  | - | 
|---|
| 15 |  | -  You should have received a copy of the GNU General Public License | 
|---|
| 16 |  | -  along with this program; if not, write to the Free Software | 
|---|
| 17 |  | -  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA | 
|---|
| 18 | 6 |  | 
|---|
| 19 | 7 | linux/include/linux/rbtree.h | 
|---|
| 20 | 8 |  | 
|---|
| .. | .. | 
|---|
| 23 | 11 | I know it's not the cleaner way,  but in C (not in C++) to get | 
|---|
| 24 | 12 | performances and genericity... | 
|---|
| 25 | 13 |  | 
|---|
| 26 |  | -  See Documentation/rbtree.txt for documentation and samples. | 
|---|
|  | 14 | +  See Documentation/core-api/rbtree.rst for documentation and samples. | 
|---|
| 27 | 15 | */ | 
|---|
| 28 | 16 |  | 
|---|
| 29 | 17 | #ifndef	_LINUX_RBTREE_H | 
|---|
| .. | .. | 
|---|
| 44 | 32 | struct rb_node *rb_node; | 
|---|
| 45 | 33 | }; | 
|---|
| 46 | 34 |  | 
|---|
| 47 |  | -/* | 
|---|
| 48 |  | - * Leftmost-cached rbtrees. | 
|---|
| 49 |  | - * | 
|---|
| 50 |  | - * We do not cache the rightmost node based on footprint | 
|---|
| 51 |  | - * size vs number of potential users that could benefit | 
|---|
| 52 |  | - * from O(1) rb_last(). Just not worth it, users that want | 
|---|
| 53 |  | - * this feature can always implement the logic explicitly. | 
|---|
| 54 |  | - * Furthermore, users that want to cache both pointers may | 
|---|
| 55 |  | - * find it a bit asymmetric, but that's ok. | 
|---|
| 56 |  | - */ | 
|---|
| 57 |  | -struct rb_root_cached { | 
|---|
| 58 |  | -	struct rb_root rb_root; | 
|---|
| 59 |  | -	struct rb_node *rb_leftmost; | 
|---|
| 60 |  | -}; | 
|---|
| 61 |  | - | 
|---|
| 62 | 35 | #define rb_parent(r)   ((struct rb_node *)((r)->__rb_parent_color & ~3)) | 
|---|
| 63 | 36 |  | 
|---|
| 64 | 37 | #define RB_ROOT	(struct rb_root) { NULL, } | 
|---|
| 65 |  | -#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL } | 
|---|
| 66 | 38 | #define	rb_entry(ptr, type, member) container_of(ptr, type, member) | 
|---|
| 67 | 39 |  | 
|---|
| 68 | 40 | #define RB_EMPTY_ROOT(root)  (READ_ONCE((root)->rb_node) == NULL) | 
|---|
| .. | .. | 
|---|
| 84 | 56 | extern struct rb_node *rb_first(const struct rb_root *); | 
|---|
| 85 | 57 | extern struct rb_node *rb_last(const struct rb_root *); | 
|---|
| 86 | 58 |  | 
|---|
| 87 |  | -extern void rb_insert_color_cached(struct rb_node *, | 
|---|
| 88 |  | -				   struct rb_root_cached *, bool); | 
|---|
| 89 |  | -extern void rb_erase_cached(struct rb_node *node, struct rb_root_cached *); | 
|---|
| 90 |  | -/* Same as rb_first(), but O(1) */ | 
|---|
| 91 |  | -#define rb_first_cached(root) (root)->rb_leftmost | 
|---|
| 92 |  | - | 
|---|
| 93 | 59 | /* Postorder iteration - always visit the parent after its children */ | 
|---|
| 94 | 60 | extern struct rb_node *rb_first_postorder(const struct rb_root *); | 
|---|
| 95 | 61 | extern struct rb_node *rb_next_postorder(const struct rb_node *); | 
|---|
| .. | .. | 
|---|
| 99 | 65 | struct rb_root *root); | 
|---|
| 100 | 66 | extern void rb_replace_node_rcu(struct rb_node *victim, struct rb_node *new, | 
|---|
| 101 | 67 | struct rb_root *root); | 
|---|
| 102 |  | -extern void rb_replace_node_cached(struct rb_node *victim, struct rb_node *new, | 
|---|
| 103 |  | -				   struct rb_root_cached *root); | 
|---|
| 104 | 68 |  | 
|---|
| 105 | 69 | static inline void rb_link_node(struct rb_node *node, struct rb_node *parent, | 
|---|
| 106 | 70 | struct rb_node **rb_link) | 
|---|
| .. | .. | 
|---|
| 148 | 112 | typeof(*pos), field); 1; }); \ | 
|---|
| 149 | 113 | pos = n) | 
|---|
| 150 | 114 |  | 
|---|
|  | 115 | +/* | 
|---|
|  | 116 | + * Leftmost-cached rbtrees. | 
|---|
|  | 117 | + * | 
|---|
|  | 118 | + * We do not cache the rightmost node based on footprint | 
|---|
|  | 119 | + * size vs number of potential users that could benefit | 
|---|
|  | 120 | + * from O(1) rb_last(). Just not worth it, users that want | 
|---|
|  | 121 | + * this feature can always implement the logic explicitly. | 
|---|
|  | 122 | + * Furthermore, users that want to cache both pointers may | 
|---|
|  | 123 | + * find it a bit asymmetric, but that's ok. | 
|---|
|  | 124 | + */ | 
|---|
|  | 125 | +struct rb_root_cached { | 
|---|
|  | 126 | +	struct rb_root rb_root; | 
|---|
|  | 127 | +	struct rb_node *rb_leftmost; | 
|---|
|  | 128 | +}; | 
|---|
|  | 129 | + | 
|---|
|  | 130 | +#define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL } | 
|---|
|  | 131 | + | 
|---|
|  | 132 | +/* Same as rb_first(), but O(1) */ | 
|---|
|  | 133 | +#define rb_first_cached(root) (root)->rb_leftmost | 
|---|
|  | 134 | + | 
|---|
|  | 135 | +static inline void rb_insert_color_cached(struct rb_node *node, | 
|---|
|  | 136 | +					  struct rb_root_cached *root, | 
|---|
|  | 137 | +					  bool leftmost) | 
|---|
|  | 138 | +{ | 
|---|
|  | 139 | +	if (leftmost) | 
|---|
|  | 140 | +		root->rb_leftmost = node; | 
|---|
|  | 141 | +	rb_insert_color(node, &root->rb_root); | 
|---|
|  | 142 | +} | 
|---|
|  | 143 | + | 
|---|
|  | 144 | +static inline void rb_erase_cached(struct rb_node *node, | 
|---|
|  | 145 | +				   struct rb_root_cached *root) | 
|---|
|  | 146 | +{ | 
|---|
|  | 147 | +	if (root->rb_leftmost == node) | 
|---|
|  | 148 | +		root->rb_leftmost = rb_next(node); | 
|---|
|  | 149 | +	rb_erase(node, &root->rb_root); | 
|---|
|  | 150 | +} | 
|---|
|  | 151 | + | 
|---|
|  | 152 | +static inline void rb_replace_node_cached(struct rb_node *victim, | 
|---|
|  | 153 | +					  struct rb_node *new, | 
|---|
|  | 154 | +					  struct rb_root_cached *root) | 
|---|
|  | 155 | +{ | 
|---|
|  | 156 | +	if (root->rb_leftmost == victim) | 
|---|
|  | 157 | +		root->rb_leftmost = new; | 
|---|
|  | 158 | +	rb_replace_node(victim, new, &root->rb_root); | 
|---|
|  | 159 | +} | 
|---|
|  | 160 | + | 
|---|
| 151 | 161 | #endif	/* _LINUX_RBTREE_H */ | 
|---|