1// SPDX-License-Identifier: GPL-2.0
2#include <errno.h>
3#include <inttypes.h>
4#include <stdlib.h>
5#include <perf/cpumap.h>
6
7#include "debug.h"
8#include "event.h"
9#include "evlist.h"
10#include "evsel.h"
11#include "thread_map.h"
12#include "tests.h"
13#include "util/mmap.h"
14#include "util/sample.h"
15#include <linux/err.h>
16#include <linux/kernel.h>
17#include <linux/string.h>
18#include <perf/evlist.h>
19#include <perf/mmap.h>
20
21/*
22 * This test will generate random numbers of calls to some getpid syscalls,
23 * then establish an mmap for a group of events that are created to monitor
24 * the syscalls.
25 *
26 * It will receive the events, using mmap, use its PERF_SAMPLE_ID generated
27 * sample.id field to map back to its respective perf_evsel instance.
28 *
29 * Then it checks if the number of syscalls reported as perf events by
30 * the kernel corresponds to the number of syscalls made.
31 */
32static int test__basic_mmap(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
33{
34	int err = TEST_FAIL;
35	union perf_event *event;
36	struct perf_thread_map *threads;
37	struct perf_cpu_map *cpus;
38	struct evlist *evlist;
39	cpu_set_t cpu_set;
40	const char *syscall_names[] = { "getsid", "getppid", "getpgid", };
41	pid_t (*syscalls[])(void) = { (void *)getsid, getppid, (void*)getpgid };
42#define nsyscalls ARRAY_SIZE(syscall_names)
43	unsigned int nr_events[nsyscalls],
44		     expected_nr_events[nsyscalls], i, j;
45	struct evsel *evsels[nsyscalls], *evsel;
46	char sbuf[STRERR_BUFSIZE];
47	struct mmap *md;
48
49	threads = thread_map__new(-1, getpid(), UINT_MAX);
50	if (threads == NULL) {
51		pr_debug("thread_map__new\n");
52		return -1;
53	}
54
55	cpus = perf_cpu_map__new_online_cpus();
56	if (cpus == NULL) {
57		pr_debug("perf_cpu_map__new\n");
58		goto out_free_threads;
59	}
60
61	CPU_ZERO(&cpu_set);
62	CPU_SET(perf_cpu_map__cpu(cpus, 0).cpu, &cpu_set);
63	sched_setaffinity(0, sizeof(cpu_set), &cpu_set);
64	if (sched_setaffinity(0, sizeof(cpu_set), &cpu_set) < 0) {
65		pr_debug("sched_setaffinity() failed on CPU %d: %s ",
66			 perf_cpu_map__cpu(cpus, 0).cpu,
67			 str_error_r(errno, sbuf, sizeof(sbuf)));
68		goto out_free_cpus;
69	}
70
71	evlist = evlist__new();
72	if (evlist == NULL) {
73		pr_debug("evlist__new\n");
74		goto out_free_cpus;
75	}
76
77	perf_evlist__set_maps(&evlist->core, cpus, threads);
78
79	for (i = 0; i < nsyscalls; ++i) {
80		char name[64];
81
82		snprintf(name, sizeof(name), "sys_enter_%s", syscall_names[i]);
83		evsels[i] = evsel__newtp("syscalls", name);
84		if (IS_ERR(evsels[i])) {
85			pr_debug("evsel__new(%s)\n", name);
86			if (PTR_ERR(evsels[i]) == -EACCES) {
87				/* Permissions failure, flag the failure as a skip. */
88				err = TEST_SKIP;
89			}
90			goto out_delete_evlist;
91		}
92
93		evsels[i]->core.attr.wakeup_events = 1;
94		evsel__set_sample_id(evsels[i], false);
95
96		evlist__add(evlist, evsels[i]);
97
98		if (evsel__open(evsels[i], cpus, threads) < 0) {
99			pr_debug("failed to open counter: %s, "
100				 "tweak /proc/sys/kernel/perf_event_paranoid?\n",
101				 str_error_r(errno, sbuf, sizeof(sbuf)));
102			goto out_delete_evlist;
103		}
104
105		nr_events[i] = 0;
106		expected_nr_events[i] = 1 + rand() % 127;
107	}
108
109	if (evlist__mmap(evlist, 128) < 0) {
110		pr_debug("failed to mmap events: %d (%s)\n", errno,
111			 str_error_r(errno, sbuf, sizeof(sbuf)));
112		goto out_delete_evlist;
113	}
114
115	for (i = 0; i < nsyscalls; ++i)
116		for (j = 0; j < expected_nr_events[i]; ++j) {
117			syscalls[i]();
118		}
119
120	md = &evlist->mmap[0];
121	if (perf_mmap__read_init(&md->core) < 0)
122		goto out_init;
123
124	while ((event = perf_mmap__read_event(&md->core)) != NULL) {
125		struct perf_sample sample;
126
127		if (event->header.type != PERF_RECORD_SAMPLE) {
128			pr_debug("unexpected %s event\n",
129				 perf_event__name(event->header.type));
130			goto out_delete_evlist;
131		}
132
133		err = evlist__parse_sample(evlist, event, &sample);
134		if (err) {
135			pr_err("Can't parse sample, err = %d\n", err);
136			goto out_delete_evlist;
137		}
138
139		err = -1;
140		evsel = evlist__id2evsel(evlist, sample.id);
141		if (evsel == NULL) {
142			pr_debug("event with id %" PRIu64
143				 " doesn't map to an evsel\n", sample.id);
144			goto out_delete_evlist;
145		}
146		nr_events[evsel->core.idx]++;
147		perf_mmap__consume(&md->core);
148	}
149	perf_mmap__read_done(&md->core);
150
151out_init:
152	err = 0;
153	evlist__for_each_entry(evlist, evsel) {
154		if (nr_events[evsel->core.idx] != expected_nr_events[evsel->core.idx]) {
155			pr_debug("expected %d %s events, got %d\n",
156				 expected_nr_events[evsel->core.idx],
157				 evsel__name(evsel), nr_events[evsel->core.idx]);
158			err = -1;
159			goto out_delete_evlist;
160		}
161	}
162
163out_delete_evlist:
164	evlist__delete(evlist);
165out_free_cpus:
166	perf_cpu_map__put(cpus);
167out_free_threads:
168	perf_thread_map__put(threads);
169	return err;
170}
171
172static int test_stat_user_read(int event)
173{
174	struct perf_counts_values counts = { .val = 0 };
175	struct perf_thread_map *threads;
176	struct perf_evsel *evsel;
177	struct perf_event_mmap_page *pc;
178	struct perf_event_attr attr = {
179		.type	= PERF_TYPE_HARDWARE,
180		.config	= event,
181#ifdef __aarch64__
182		.config1 = 0x2,		/* Request user access */
183#endif
184	};
185	int err, i, ret = TEST_FAIL;
186	bool opened = false, mapped = false;
187
188	threads = perf_thread_map__new_dummy();
189	TEST_ASSERT_VAL("failed to create threads", threads);
190
191	perf_thread_map__set_pid(threads, 0, 0);
192
193	evsel = perf_evsel__new(&attr);
194	TEST_ASSERT_VAL("failed to create evsel", evsel);
195
196	err = perf_evsel__open(evsel, NULL, threads);
197	if (err) {
198		pr_err("failed to open evsel: %s\n", strerror(-err));
199		ret = TEST_SKIP;
200		goto out;
201	}
202	opened = true;
203
204	err = perf_evsel__mmap(evsel, 0);
205	if (err) {
206		pr_err("failed to mmap evsel: %s\n", strerror(-err));
207		goto out;
208	}
209	mapped = true;
210
211	pc = perf_evsel__mmap_base(evsel, 0, 0);
212	if (!pc) {
213		pr_err("failed to get mmapped address\n");
214		goto out;
215	}
216
217	if (!pc->cap_user_rdpmc || !pc->index) {
218		pr_err("userspace counter access not %s\n",
219			!pc->cap_user_rdpmc ? "supported" : "enabled");
220		ret = TEST_SKIP;
221		goto out;
222	}
223	if (pc->pmc_width < 32) {
224		pr_err("userspace counter width not set (%d)\n", pc->pmc_width);
225		goto out;
226	}
227
228	perf_evsel__read(evsel, 0, 0, &counts);
229	if (counts.val == 0) {
230		pr_err("failed to read value for evsel\n");
231		goto out;
232	}
233
234	for (i = 0; i < 5; i++) {
235		volatile int count = 0x10000 << i;
236		__u64 start, end, last = 0;
237
238		pr_debug("\tloop = %u, ", count);
239
240		perf_evsel__read(evsel, 0, 0, &counts);
241		start = counts.val;
242
243		while (count--) ;
244
245		perf_evsel__read(evsel, 0, 0, &counts);
246		end = counts.val;
247
248		if ((end - start) < last) {
249			pr_err("invalid counter data: end=%llu start=%llu last= %llu\n",
250				end, start, last);
251			goto out;
252		}
253		last = end - start;
254		pr_debug("count = %llu\n", end - start);
255	}
256	ret = TEST_OK;
257
258out:
259	if (mapped)
260		perf_evsel__munmap(evsel);
261	if (opened)
262		perf_evsel__close(evsel);
263	perf_evsel__delete(evsel);
264
265	perf_thread_map__put(threads);
266	return ret;
267}
268
269static int test__mmap_user_read_instr(struct test_suite *test __maybe_unused,
270				      int subtest __maybe_unused)
271{
272	return test_stat_user_read(PERF_COUNT_HW_INSTRUCTIONS);
273}
274
275static int test__mmap_user_read_cycles(struct test_suite *test __maybe_unused,
276				       int subtest __maybe_unused)
277{
278	return test_stat_user_read(PERF_COUNT_HW_CPU_CYCLES);
279}
280
281static struct test_case tests__basic_mmap[] = {
282	TEST_CASE_REASON("Read samples using the mmap interface",
283			 basic_mmap,
284			 "permissions"),
285	TEST_CASE_REASON("User space counter reading of instructions",
286			 mmap_user_read_instr,
287#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) || \
288			 (defined(__riscv) && __riscv_xlen == 64)
289			 "permissions"
290#else
291			 "unsupported"
292#endif
293		),
294	TEST_CASE_REASON("User space counter reading of cycles",
295			 mmap_user_read_cycles,
296#if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__) || \
297			 (defined(__riscv) && __riscv_xlen == 64)
298			 "permissions"
299#else
300			 "unsupported"
301#endif
302		),
303	{	.name = NULL, }
304};
305
306struct test_suite suite__basic_mmap = {
307	.desc = "mmap interface tests",
308	.test_cases = tests__basic_mmap,
309};
310