tools/perf/tests/mmap-basic.c

   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  */
  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
 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
 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
 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 };