xref: /linux/tools/perf/util/call-path.c (revision ebf68996de0ab250c5d520eb2291ab65643e9a1e)
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 
10 #include "util.h"
11 #include "call-path.h"
12 
13 static void call_path__init(struct call_path *cp, struct call_path *parent,
14 			    struct symbol *sym, u64 ip, bool in_kernel)
15 {
16 	cp->parent = parent;
17 	cp->sym = sym;
18 	cp->ip = sym ? 0 : ip;
19 	cp->db_id = 0;
20 	cp->in_kernel = in_kernel;
21 	RB_CLEAR_NODE(&cp->rb_node);
22 	cp->children = RB_ROOT;
23 }
24 
25 struct call_path_root *call_path_root__new(void)
26 {
27 	struct call_path_root *cpr;
28 
29 	cpr = zalloc(sizeof(struct call_path_root));
30 	if (!cpr)
31 		return NULL;
32 	call_path__init(&cpr->call_path, NULL, NULL, 0, false);
33 	INIT_LIST_HEAD(&cpr->blocks);
34 	return cpr;
35 }
36 
37 void call_path_root__free(struct call_path_root *cpr)
38 {
39 	struct call_path_block *pos, *n;
40 
41 	list_for_each_entry_safe(pos, n, &cpr->blocks, node) {
42 		list_del(&pos->node);
43 		free(pos);
44 	}
45 	free(cpr);
46 }
47 
48 static struct call_path *call_path__new(struct call_path_root *cpr,
49 					struct call_path *parent,
50 					struct symbol *sym, u64 ip,
51 					bool in_kernel)
52 {
53 	struct call_path_block *cpb;
54 	struct call_path *cp;
55 	size_t n;
56 
57 	if (cpr->next < cpr->sz) {
58 		cpb = list_last_entry(&cpr->blocks, struct call_path_block,
59 				      node);
60 	} else {
61 		cpb = zalloc(sizeof(struct call_path_block));
62 		if (!cpb)
63 			return NULL;
64 		list_add_tail(&cpb->node, &cpr->blocks);
65 		cpr->sz += CALL_PATH_BLOCK_SIZE;
66 	}
67 
68 	n = cpr->next++ & CALL_PATH_BLOCK_MASK;
69 	cp = &cpb->cp[n];
70 
71 	call_path__init(cp, parent, sym, ip, in_kernel);
72 
73 	return cp;
74 }
75 
76 struct call_path *call_path__findnew(struct call_path_root *cpr,
77 				     struct call_path *parent,
78 				     struct symbol *sym, u64 ip, u64 ks)
79 {
80 	struct rb_node **p;
81 	struct rb_node *node_parent = NULL;
82 	struct call_path *cp;
83 	bool in_kernel = ip >= ks;
84 
85 	if (sym)
86 		ip = 0;
87 
88 	if (!parent)
89 		return call_path__new(cpr, parent, sym, ip, in_kernel);
90 
91 	p = &parent->children.rb_node;
92 	while (*p != NULL) {
93 		node_parent = *p;
94 		cp = rb_entry(node_parent, struct call_path, rb_node);
95 
96 		if (cp->sym == sym && cp->ip == ip)
97 			return cp;
98 
99 		if (sym < cp->sym || (sym == cp->sym && ip < cp->ip))
100 			p = &(*p)->rb_left;
101 		else
102 			p = &(*p)->rb_right;
103 	}
104 
105 	cp = call_path__new(cpr, parent, sym, ip, in_kernel);
106 	if (!cp)
107 		return NULL;
108 
109 	rb_link_node(&cp->rb_node, node_parent, p);
110 	rb_insert_color(&cp->rb_node, &parent->children);
111 
112 	return cp;
113 }
114