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(buf: name, size: sizeof(name), fmt: "sys_enter_%s", syscall_names[i]);
83 evsels[i] = evsel__newtp("syscalls", name);
84 if (IS_ERR(ptr: evsels[i])) {
85 pr_debug("evsel__new(%s)\n", name);
86 if (PTR_ERR(ptr: 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

source code of linux/tools/perf/tests/mmap-basic.c