1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * call-path.h: Manipulate a tree data structure containing function call paths
4 * Copyright (c) 2014, Intel Corporation.
5 */
6
7 #include <linux/rbtree.h>
8 #include <linux/list.h>
9 #include <linux/zalloc.h>
10 #include <stdlib.h>
11
12 #include "call-path.h"
13
14 static void call_path__init(struct call_path *cp, struct call_path *parent,
15 struct symbol *sym, u64 ip, bool in_kernel)
16 {
17 cp->parent = parent;
18 cp->sym = sym;
19 cp->ip = sym ? 0 : ip;
20 cp->db_id = 0;
21 cp->in_kernel = in_kernel;
22 RB_CLEAR_NODE(&cp->rb_node);
23 cp->children = RB_ROOT;
24 }
25
26 struct call_path_root *call_path_root__new(void)
27 {
28 struct call_path_root *cpr;
29
30 cpr = zalloc(sizeof(struct call_path_root));
31 if (!cpr)
32 return NULL;
33 call_path__init(&cpr->call_path, NULL, NULL, 0, false);
34 INIT_LIST_HEAD(&cpr->blocks);
35 return cpr;
36 }
37
38 void call_path_root__free(struct call_path_root *cpr)
39 {
40 struct call_path_block *pos, *n;
41
42 list_for_each_entry_safe(pos, n, &cpr->blocks, node) {
43 list_del_init(&pos->node);
44 free(pos);
45 }
46 free(cpr);
47 }
48
49 static struct call_path *call_path__new(struct call_path_root *cpr,
50 struct call_path *parent,
51 struct symbol *sym, u64 ip,
52 bool in_kernel)
53 {
54 struct call_path_block *cpb;
55 struct call_path *cp;
56 size_t n;
57
58 if (cpr->next < cpr->sz) {
59 cpb = list_last_entry(&cpr->blocks, struct call_path_block,
60 node);
61 } else {
62 cpb = zalloc(sizeof(struct call_path_block));
63 if (!cpb)
64 return NULL;
65 list_add_tail(&cpb->node, &cpr->blocks);
66 cpr->sz += CALL_PATH_BLOCK_SIZE;
67 }
68
69 n = cpr->next++ & CALL_PATH_BLOCK_MASK;
70 cp = &cpb->cp[n];
71
72 call_path__init(cp, parent, sym, ip, in_kernel);
73
74 return cp;
75 }
76
77 struct call_path *call_path__findnew(struct call_path_root *cpr,
78 struct call_path *parent,
79 struct symbol *sym, u64 ip, u64 ks)
80 {
81 struct rb_node **p;
82 struct rb_node *node_parent = NULL;
83 struct call_path *cp;
84 bool in_kernel = ip >= ks;
85
86 if (sym)
87 ip = 0;
88
89 if (!parent)
90 return call_path__new(cpr, parent, sym, ip, in_kernel);
91
92 p = &parent->children.rb_node;
93 while (*p != NULL) {
94 node_parent = *p;
95 cp = rb_entry(node_parent, struct call_path, rb_node);
96
97 if (cp->sym == sym && cp->ip == ip)
98 return cp;
99
100 if (sym < cp->sym || (sym == cp->sym && ip < cp->ip))
101 p = &(*p)->rb_left;
102 else
103 p = &(*p)->rb_right;
104 }
105
106 cp = call_path__new(cpr, parent, sym, ip, in_kernel);
107 if (!cp)
108 return NULL;
109
110 rb_link_node(&cp->rb_node, node_parent, p);
111 rb_insert_color(&cp->rb_node, &parent->children);
112
113 return cp;
114 }
115
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