summaryrefslogtreecommitdiff
path: root/tools/perf/tests/mmap-thread-lookup.c
blob: 3c3f3e029e33bd77cb5b2d7284b6e3cb01735237 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
// SPDX-License-Identifier: GPL-2.0
#include <inttypes.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <pthread.h>
#include <stdlib.h>
#include <stdio.h>
#include "debug.h"
#include "tests.h"
#include "machine.h"
#include "thread_map.h"
#include "symbol.h"
#include "thread.h"
#include "util.h"

#define THREADS 4

static int go_away;

struct thread_data {
	pthread_t	pt;
	pid_t		tid;
	void		*map;
	int		ready[2];
};

static struct thread_data threads[THREADS];

static int thread_init(struct thread_data *td)
{
	void *map;

	map = mmap(NULL, page_size,
		   PROT_READ|PROT_WRITE|PROT_EXEC,
		   MAP_SHARED|MAP_ANONYMOUS, -1, 0);

	if (map == MAP_FAILED) {
		perror("mmap failed");
		return -1;
	}

	td->map = map;
	td->tid = syscall(SYS_gettid);

	pr_debug("tid = %d, map = %p\n", td->tid, map);
	return 0;
}

static void *thread_fn(void *arg)
{
	struct thread_data *td = arg;
	ssize_t ret;
	int go;

	if (thread_init(td))
		return NULL;

	/* Signal thread_create thread is initialized. */
	ret = write(td->ready[1], &go, sizeof(int));
	if (ret != sizeof(int)) {
		pr_err("failed to notify\n");
		return NULL;
	}

	while (!go_away) {
		/* Waiting for main thread to kill us. */
		usleep(100);
	}

	munmap(td->map, page_size);
	return NULL;
}

static int thread_create(int i)
{
	struct thread_data *td = &threads[i];
	int err, go;

	if (pipe(td->ready))
		return -1;

	err = pthread_create(&td->pt, NULL, thread_fn, td);
	if (!err) {
		/* Wait for thread initialization. */
		ssize_t ret = read(td->ready[0], &go, sizeof(int));
		err = ret != sizeof(int);
	}

	close(td->ready[0]);
	close(td->ready[1]);
	return err;
}

static int threads_create(void)
{
	struct thread_data *td0 = &threads[0];
	int i, err = 0;

	go_away = 0;

	/* 0 is main thread */
	if (thread_init(td0))
		return -1;

	for (i = 1; !err && i < THREADS; i++)
		err = thread_create(i);

	return err;
}

static int threads_destroy(void)
{
	struct thread_data *td0 = &threads[0];
	int i, err = 0;

	/* cleanup the main thread */
	munmap(td0->map, page_size);

	go_away = 1;

	for (i = 1; !err && i < THREADS; i++)
		err = pthread_join(threads[i].pt, NULL);

	return err;
}

typedef int (*synth_cb)(struct machine *machine);

static int synth_all(struct machine *machine)
{
	return perf_event__synthesize_threads(NULL,
					      perf_event__process,
					      machine, 0, 500);
}

static int synth_process(struct machine *machine)
{
	struct thread_map *map;
	int err;

	map = thread_map__new_by_pid(getpid());

	err = perf_event__synthesize_thread_map(NULL, map,
						perf_event__process,
						machine, 0, 500);

	thread_map__put(map);
	return err;
}

static int mmap_events(synth_cb synth)
{
	struct machine *machine;
	int err, i;

	/*
	 * The threads_create will not return before all threads
	 * are spawned and all created memory map.
	 *
	 * They will loop until threads_destroy is called, so we
	 * can safely run synthesizing function.
	 */
	TEST_ASSERT_VAL("failed to create threads", !threads_create());

	machine = machine__new_host();

	dump_trace = verbose > 1 ? 1 : 0;

	err = synth(machine);

	dump_trace = 0;

	TEST_ASSERT_VAL("failed to destroy threads", !threads_destroy());
	TEST_ASSERT_VAL("failed to synthesize maps", !err);

	/*
	 * All data is synthesized, try to find map for each
	 * thread object.
	 */
	for (i = 0; i < THREADS; i++) {
		struct thread_data *td = &threads[i];
		struct addr_location al;
		struct thread *thread;

		thread = machine__findnew_thread(machine, getpid(), td->tid);

		pr_debug("looking for map %p\n", td->map);

		thread__find_addr_map(thread,
				      PERF_RECORD_MISC_USER, MAP__FUNCTION,
				      (unsigned long) (td->map + 1), &al);

		thread__put(thread);

		if (!al.map) {
			pr_debug("failed, couldn't find map\n");
			err = -1;
			break;
		}

		pr_debug("map %p, addr %" PRIx64 "\n", al.map, al.map->start);
	}

	machine__delete_threads(machine);
	machine__delete(machine);
	return err;
}

/*
 * This test creates 'THREADS' number of threads (including
 * main thread) and each thread creates memory map.
 *
 * When threads are created, we synthesize them with both
 * (separate tests):
 *   perf_event__synthesize_thread_map (process based)
 *   perf_event__synthesize_threads    (global)
 *
 * We test we can find all memory maps via:
 *   thread__find_addr_map
 *
 * by using all thread objects.
 */
int test__mmap_thread_lookup(struct test *test __maybe_unused, int subtest __maybe_unused)
{
	/* perf_event__synthesize_threads synthesize */
	TEST_ASSERT_VAL("failed with sythesizing all",
			!mmap_events(synth_all));

	/* perf_event__synthesize_thread_map synthesize */
	TEST_ASSERT_VAL("failed with sythesizing process",
			!mmap_events(synth_process));

	return 0;
}