tiobench: remove duplicate profile group
[fio.git] / rbtree.h
CommitLineData
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1/*
2 Red Black Trees
3 (C) 1999 Andrea Arcangeli <andrea@suse.de>
4
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
19 linux/include/linux/rbtree.h
20
21 To use rbtrees you'll have to implement your own insert and search cores.
22 This will avoid us to use callbacks and to drop drammatically performances.
23 I know it's not the cleaner way, but in C (not in C++) to get
24 performances and genericity...
25
26 Some example of insert and search follows here. The search is a plain
27 normal search over an ordered tree. The insert instead must be implemented
28 int two steps: as first thing the code must insert the element in
29 order as a red leaf in the tree, then the support library function
30 rb_insert_color() must be called. Such function will do the
31 not trivial work to rebalance the rbtree if necessary.
32
33-----------------------------------------------------------------------
34static inline struct page * rb_search_page_cache(struct inode * inode,
35 unsigned long offset)
36{
37 struct rb_node * n = inode->i_rb_page_cache.rb_node;
38 struct page * page;
39
40 while (n)
41 {
42 page = rb_entry(n, struct page, rb_page_cache);
43
44 if (offset < page->offset)
45 n = n->rb_left;
46 else if (offset > page->offset)
47 n = n->rb_right;
48 else
49 return page;
50 }
51 return NULL;
52}
53
54static inline struct page * __rb_insert_page_cache(struct inode * inode,
55 unsigned long offset,
56 struct rb_node * node)
57{
58 struct rb_node ** p = &inode->i_rb_page_cache.rb_node;
59 struct rb_node * parent = NULL;
60 struct page * page;
61
62 while (*p)
63 {
64 parent = *p;
65 page = rb_entry(parent, struct page, rb_page_cache);
66
67 if (offset < page->offset)
68 p = &(*p)->rb_left;
69 else if (offset > page->offset)
70 p = &(*p)->rb_right;
71 else
72 return page;
73 }
74
75 rb_link_node(node, parent, p);
76
77 return NULL;
78}
79
80static inline struct page * rb_insert_page_cache(struct inode * inode,
81 unsigned long offset,
82 struct rb_node * node)
83{
84 struct page * ret;
85 if ((ret = __rb_insert_page_cache(inode, offset, node)))
86 goto out;
87 rb_insert_color(node, &inode->i_rb_page_cache);
88 out:
89 return ret;
90}
91-----------------------------------------------------------------------
92*/
93
94#ifndef _LINUX_RBTREE_H
95#define _LINUX_RBTREE_H
96
3902866c 97#include <stdlib.h>
e43606c2 98#include <inttypes.h>
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99
100struct rb_node
101{
e43606c2 102 intptr_t rb_parent_color;
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103#define RB_RED 0
104#define RB_BLACK 1
105 struct rb_node *rb_right;
106 struct rb_node *rb_left;
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107} __attribute__((aligned(sizeof(long))));
108 /* The alignment might seem pointless, but allegedly CRIS needs it */
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109
110struct rb_root
111{
112 struct rb_node *rb_node;
113};
114
4b87898e 115
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116#define rb_parent(r) ((struct rb_node *)((r)->rb_parent_color & ~3))
117#define rb_color(r) ((r)->rb_parent_color & 1)
118#define rb_is_red(r) (!rb_color(r))
119#define rb_is_black(r) rb_color(r)
120#define rb_set_red(r) do { (r)->rb_parent_color &= ~1; } while (0)
121#define rb_set_black(r) do { (r)->rb_parent_color |= 1; } while (0)
122
123static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
124{
e43606c2 125 rb->rb_parent_color = (rb->rb_parent_color & 3) | (uintptr_t)p;
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126}
127static inline void rb_set_color(struct rb_node *rb, int color)
128{
129 rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
130}
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131
132#define RB_ROOT (struct rb_root) { NULL, }
133#define rb_entry(ptr, type, member) container_of(ptr, type, member)
134
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135#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
136#define RB_EMPTY_NODE(node) (rb_parent(node) == node)
137#define RB_CLEAR_NODE(node) (rb_set_parent(node, node))
138
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139extern void rb_insert_color(struct rb_node *, struct rb_root *);
140extern void rb_erase(struct rb_node *, struct rb_root *);
141
142/* Find logical next and previous nodes in a tree */
4b87898e 143extern struct rb_node *rb_first(struct rb_root *);
8f2b1374 144extern struct rb_node *rb_next(const struct rb_node *);
44b5374f 145
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146static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
147 struct rb_node ** rb_link)
148{
e43606c2 149 node->rb_parent_color = (uintptr_t)parent;
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150 node->rb_left = node->rb_right = NULL;
151
152 *rb_link = node;
153}
154
155#endif /* _LINUX_RBTREE_H */