1 /*
2 * call-path.h: Manipulate a tree data structure containing function call paths
3 * Copyright (c) 2014, Intel Corporation.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 */
15
16 #include <linux/rbtree.h>
17 #include <linux/list.h>
18
19 #include "util.h"
20 #include "call-path.h"
21
call_path__init(struct call_path * cp,struct call_path * parent,struct symbol * sym,u64 ip,bool in_kernel)22 static void call_path__init(struct call_path *cp, struct call_path *parent,
23 struct symbol *sym, u64 ip, bool in_kernel)
24 {
25 cp->parent = parent;
26 cp->sym = sym;
27 cp->ip = sym ? 0 : ip;
28 cp->db_id = 0;
29 cp->in_kernel = in_kernel;
30 RB_CLEAR_NODE(&cp->rb_node);
31 cp->children = RB_ROOT;
32 }
33
call_path_root__new(void)34 struct call_path_root *call_path_root__new(void)
35 {
36 struct call_path_root *cpr;
37
38 cpr = zalloc(sizeof(struct call_path_root));
39 if (!cpr)
40 return NULL;
41 call_path__init(&cpr->call_path, NULL, NULL, 0, false);
42 INIT_LIST_HEAD(&cpr->blocks);
43 return cpr;
44 }
45
call_path_root__free(struct call_path_root * cpr)46 void call_path_root__free(struct call_path_root *cpr)
47 {
48 struct call_path_block *pos, *n;
49
50 list_for_each_entry_safe(pos, n, &cpr->blocks, node) {
51 list_del(&pos->node);
52 free(pos);
53 }
54 free(cpr);
55 }
56
call_path__new(struct call_path_root * cpr,struct call_path * parent,struct symbol * sym,u64 ip,bool in_kernel)57 static struct call_path *call_path__new(struct call_path_root *cpr,
58 struct call_path *parent,
59 struct symbol *sym, u64 ip,
60 bool in_kernel)
61 {
62 struct call_path_block *cpb;
63 struct call_path *cp;
64 size_t n;
65
66 if (cpr->next < cpr->sz) {
67 cpb = list_last_entry(&cpr->blocks, struct call_path_block,
68 node);
69 } else {
70 cpb = zalloc(sizeof(struct call_path_block));
71 if (!cpb)
72 return NULL;
73 list_add_tail(&cpb->node, &cpr->blocks);
74 cpr->sz += CALL_PATH_BLOCK_SIZE;
75 }
76
77 n = cpr->next++ & CALL_PATH_BLOCK_MASK;
78 cp = &cpb->cp[n];
79
80 call_path__init(cp, parent, sym, ip, in_kernel);
81
82 return cp;
83 }
84
call_path__findnew(struct call_path_root * cpr,struct call_path * parent,struct symbol * sym,u64 ip,u64 ks)85 struct call_path *call_path__findnew(struct call_path_root *cpr,
86 struct call_path *parent,
87 struct symbol *sym, u64 ip, u64 ks)
88 {
89 struct rb_node **p;
90 struct rb_node *node_parent = NULL;
91 struct call_path *cp;
92 bool in_kernel = ip >= ks;
93
94 if (sym)
95 ip = 0;
96
97 if (!parent)
98 return call_path__new(cpr, parent, sym, ip, in_kernel);
99
100 p = &parent->children.rb_node;
101 while (*p != NULL) {
102 node_parent = *p;
103 cp = rb_entry(node_parent, struct call_path, rb_node);
104
105 if (cp->sym == sym && cp->ip == ip)
106 return cp;
107
108 if (sym < cp->sym || (sym == cp->sym && ip < cp->ip))
109 p = &(*p)->rb_left;
110 else
111 p = &(*p)->rb_right;
112 }
113
114 cp = call_path__new(cpr, parent, sym, ip, in_kernel);
115 if (!cp)
116 return NULL;
117
118 rb_link_node(&cp->rb_node, node_parent, p);
119 rb_insert_color(&cp->rb_node, &parent->children);
120
121 return cp;
122 }
123