aboutsummaryrefslogtreecommitdiffstats
path: root/include
diff options
context:
space:
mode:
authorMichel Lespinasse <walken@google.com>2012-10-08 19:31:35 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-09 03:22:40 -0400
commit9826a516ff77c5820e591211e4f3e58ff36f46be (patch)
treebdec1e2fe5ff95569795069bac73977faba17d57 /include
parent9c079add0d0f45220f4bb37febf0621137ec2d38 (diff)
mm: interval tree updates
Update the generic interval tree code that was introduced in "mm: replace vma prio_tree with an interval tree". Changes: - fixed 'endpoing' typo noticed by Andrew Morton - replaced include/linux/interval_tree_tmpl.h, which was used as a template (including it automatically defined the interval tree functions) with include/linux/interval_tree_generic.h, which only defines a preprocessor macro INTERVAL_TREE_DEFINE(), which itself defines the interval tree functions when invoked. Now that is a very long macro which is unfortunate, but it does make the usage sites (lib/interval_tree.c and mm/interval_tree.c) a bit nicer than previously. - make use of RB_DECLARE_CALLBACKS() in the INTERVAL_TREE_DEFINE() macro, instead of duplicating that code in the interval tree template. - replaced vma_interval_tree_add(), which was actually handling the nonlinear and interval tree cases, with vma_interval_tree_insert_after() which handles only the interval tree case and has an API that is more consistent with the other interval tree handling functions. The nonlinear case is now handled explicitly in kernel/fork.c dup_mmap(). Signed-off-by: Michel Lespinasse <walken@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Daniel Santos <daniel.santos@pobox.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include')
-rw-r--r--include/linux/interval_tree_generic.h191
-rw-r--r--include/linux/interval_tree_tmpl.h219
-rw-r--r--include/linux/mm.h6
3 files changed, 194 insertions, 222 deletions
diff --git a/include/linux/interval_tree_generic.h b/include/linux/interval_tree_generic.h
new file mode 100644
index 000000000000..58370e1862ad
--- /dev/null
+++ b/include/linux/interval_tree_generic.h
@@ -0,0 +1,191 @@
1/*
2 Interval Trees
3 (C) 2012 Michel Lespinasse <walken@google.com>
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 include/linux/interval_tree_generic.h
20*/
21
22#include <linux/rbtree_augmented.h>
23
24/*
25 * Template for implementing interval trees
26 *
27 * ITSTRUCT: struct type of the interval tree nodes
28 * ITRB: name of struct rb_node field within ITSTRUCT
29 * ITTYPE: type of the interval endpoints
30 * ITSUBTREE: name of ITTYPE field within ITSTRUCT holding last-in-subtree
31 * ITSTART(n): start endpoint of ITSTRUCT node n
32 * ITLAST(n): last endpoint of ITSTRUCT node n
33 * ITSTATIC: 'static' or empty
34 * ITPREFIX: prefix to use for the inline tree definitions
35 *
36 * Note - before using this, please consider if non-generic version
37 * (interval_tree.h) would work for you...
38 */
39
40#define INTERVAL_TREE_DEFINE(ITSTRUCT, ITRB, ITTYPE, ITSUBTREE, \
41 ITSTART, ITLAST, ITSTATIC, ITPREFIX) \
42 \
43/* Callbacks for augmented rbtree insert and remove */ \
44 \
45static inline ITTYPE ITPREFIX ## _compute_subtree_last(ITSTRUCT *node) \
46{ \
47 ITTYPE max = ITLAST(node), subtree_last; \
48 if (node->ITRB.rb_left) { \
49 subtree_last = rb_entry(node->ITRB.rb_left, \
50 ITSTRUCT, ITRB)->ITSUBTREE; \
51 if (max < subtree_last) \
52 max = subtree_last; \
53 } \
54 if (node->ITRB.rb_right) { \
55 subtree_last = rb_entry(node->ITRB.rb_right, \
56 ITSTRUCT, ITRB)->ITSUBTREE; \
57 if (max < subtree_last) \
58 max = subtree_last; \
59 } \
60 return max; \
61} \
62 \
63RB_DECLARE_CALLBACKS(static, ITPREFIX ## _augment, ITSTRUCT, ITRB, \
64 ITTYPE, ITSUBTREE, ITPREFIX ## _compute_subtree_last) \
65 \
66/* Insert / remove interval nodes from the tree */ \
67 \
68ITSTATIC void ITPREFIX ## _insert(ITSTRUCT *node, struct rb_root *root) \
69{ \
70 struct rb_node **link = &root->rb_node, *rb_parent = NULL; \
71 ITTYPE start = ITSTART(node), last = ITLAST(node); \
72 ITSTRUCT *parent; \
73 \
74 while (*link) { \
75 rb_parent = *link; \
76 parent = rb_entry(rb_parent, ITSTRUCT, ITRB); \
77 if (parent->ITSUBTREE < last) \
78 parent->ITSUBTREE = last; \
79 if (start < ITSTART(parent)) \
80 link = &parent->ITRB.rb_left; \
81 else \
82 link = &parent->ITRB.rb_right; \
83 } \
84 \
85 node->ITSUBTREE = last; \
86 rb_link_node(&node->ITRB, rb_parent, link); \
87 rb_insert_augmented(&node->ITRB, root, &ITPREFIX ## _augment); \
88} \
89 \
90ITSTATIC void ITPREFIX ## _remove(ITSTRUCT *node, struct rb_root *root) \
91{ \
92 rb_erase_augmented(&node->ITRB, root, &ITPREFIX ## _augment); \
93} \
94 \
95/* \
96 * Iterate over intervals intersecting [start;last] \
97 * \
98 * Note that a node's interval intersects [start;last] iff: \
99 * Cond1: ITSTART(node) <= last \
100 * and \
101 * Cond2: start <= ITLAST(node) \
102 */ \
103 \
104static ITSTRUCT * \
105ITPREFIX ## _subtree_search(ITSTRUCT *node, ITTYPE start, ITTYPE last) \
106{ \
107 while (true) { \
108 /* \
109 * Loop invariant: start <= node->ITSUBTREE \
110 * (Cond2 is satisfied by one of the subtree nodes) \
111 */ \
112 if (node->ITRB.rb_left) { \
113 ITSTRUCT *left = rb_entry(node->ITRB.rb_left, \
114 ITSTRUCT, ITRB); \
115 if (start <= left->ITSUBTREE) { \
116 /* \
117 * Some nodes in left subtree satisfy Cond2. \
118 * Iterate to find the leftmost such node N. \
119 * If it also satisfies Cond1, that's the \
120 * match we are looking for. Otherwise, there \
121 * is no matching interval as nodes to the \
122 * right of N can't satisfy Cond1 either. \
123 */ \
124 node = left; \
125 continue; \
126 } \
127 } \
128 if (ITSTART(node) <= last) { /* Cond1 */ \
129 if (start <= ITLAST(node)) /* Cond2 */ \
130 return node; /* node is leftmost match */ \
131 if (node->ITRB.rb_right) { \
132 node = rb_entry(node->ITRB.rb_right, \
133 ITSTRUCT, ITRB); \
134 if (start <= node->ITSUBTREE) \
135 continue; \
136 } \
137 } \
138 return NULL; /* No match */ \
139 } \
140} \
141 \
142ITSTATIC ITSTRUCT * \
143ITPREFIX ## _iter_first(struct rb_root *root, ITTYPE start, ITTYPE last) \
144{ \
145 ITSTRUCT *node; \
146 \
147 if (!root->rb_node) \
148 return NULL; \
149 node = rb_entry(root->rb_node, ITSTRUCT, ITRB); \
150 if (node->ITSUBTREE < start) \
151 return NULL; \
152 return ITPREFIX ## _subtree_search(node, start, last); \
153} \
154 \
155ITSTATIC ITSTRUCT * \
156ITPREFIX ## _iter_next(ITSTRUCT *node, ITTYPE start, ITTYPE last) \
157{ \
158 struct rb_node *rb = node->ITRB.rb_right, *prev; \
159 \
160 while (true) {