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