xref: /openbmc/linux/tools/perf/util/call-path.c (revision e15a5365)
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