xref: /linux/tools/lib/perf/threadmap.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <perf/threadmap.h>
3 #include <stdlib.h>
4 #include <linux/refcount.h>
5 #include <internal/threadmap.h>
6 #include <string.h>
7 #include <asm/bug.h>
8 #include <stdio.h>
9 
10 static void perf_thread_map__reset(struct perf_thread_map *map, int start, int nr)
11 {
12 	size_t size = (nr - start) * sizeof(map->map[0]);
13 
14 	memset(&map->map[start], 0, size);
15 	map->err_thread = -1;
16 }
17 
18 struct perf_thread_map *perf_thread_map__realloc(struct perf_thread_map *map, int nr)
19 {
20 	size_t size = sizeof(*map) + sizeof(map->map[0]) * nr;
21 	int start = map ? map->nr : 0;
22 
23 	map = realloc(map, size);
24 	/*
25 	 * We only realloc to add more items, let's reset new items.
26 	 */
27 	if (map)
28 		perf_thread_map__reset(map, start, nr);
29 
30 	return map;
31 }
32 
33 #define thread_map__alloc(__nr) perf_thread_map__realloc(NULL, __nr)
34 
35 void perf_thread_map__set_pid(struct perf_thread_map *map, int idx, pid_t pid)
36 {
37 	map->map[idx].pid = pid;
38 }
39 
40 char *perf_thread_map__comm(struct perf_thread_map *map, int idx)
41 {
42 	return map->map[idx].comm;
43 }
44 
45 struct perf_thread_map *perf_thread_map__new_array(int nr_threads, pid_t *array)
46 {
47 	struct perf_thread_map *threads = thread_map__alloc(nr_threads);
48 	int i;
49 
50 	if (!threads)
51 		return NULL;
52 
53 	for (i = 0; i < nr_threads; i++)
54 		perf_thread_map__set_pid(threads, i, array ? array[i] : -1);
55 
56 	threads->nr = nr_threads;
57 	refcount_set(&threads->refcnt, 1);
58 
59 	return threads;
60 }
61 
62 struct perf_thread_map *perf_thread_map__new_dummy(void)
63 {
64 	return perf_thread_map__new_array(1, NULL);
65 }
66 
67 static void perf_thread_map__delete(struct perf_thread_map *threads)
68 {
69 	if (threads) {
70 		int i;
71 
72 		WARN_ONCE(refcount_read(&threads->refcnt) != 0,
73 			  "thread map refcnt unbalanced\n");
74 		for (i = 0; i < threads->nr; i++)
75 			free(perf_thread_map__comm(threads, i));
76 		free(threads);
77 	}
78 }
79 
80 struct perf_thread_map *perf_thread_map__get(struct perf_thread_map *map)
81 {
82 	if (map)
83 		refcount_inc(&map->refcnt);
84 	return map;
85 }
86 
87 void perf_thread_map__put(struct perf_thread_map *map)
88 {
89 	if (map && refcount_dec_and_test(&map->refcnt))
90 		perf_thread_map__delete(map);
91 }
92 
93 int perf_thread_map__nr(struct perf_thread_map *threads)
94 {
95 	return threads ? threads->nr : 1;
96 }
97 
98 pid_t perf_thread_map__pid(struct perf_thread_map *map, int idx)
99 {
100 	return map->map[idx].pid;
101 }
102