tools/perf/bench/inject-buildid.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <stdlib.h>
   3 #include <stddef.h>
   4 #include <ftw.h>
   5 #include <fcntl.h>
   6 #include <errno.h>
   7 #include <unistd.h>
   8 #include <pthread.h>
   9 #include <sys/mman.h>
  10 #include <sys/wait.h>
  11 #include <linux/kernel.h>
  12 #include <linux/time64.h>
  13 #include <linux/list.h>
  14 #include <linux/err.h>
  15 #include <internal/lib.h>
  16 #include <subcmd/parse-options.h>
  17
  18 #include "bench.h"
  19 #include "util/data.h"
  20 #include "util/stat.h"
  21 #include "util/debug.h"
  22 #include "util/event.h"
  23 #include "util/symbol.h"
  24 #include "util/session.h"
  25 #include "util/build-id.h"
  26 #include "util/synthetic-events.h"
  27
  28 #define MMAP_DEV_MAJOR  8
  29 #define DSO_MMAP_RATIO  4
  30
  31 static unsigned int iterations = 100;
  32 static unsigned int nr_mmaps   = 100;
  33 static unsigned int nr_samples = 100;  /* samples per mmap */
  34
  35 static u64 bench_sample_type;
  36 static u16 bench_id_hdr_size;
  37
  38 struct bench_data {
  39         int                     pid;
  40         int                     input_pipe[2];
  41         int                     output_pipe[2];
  42         pthread_t               th;
  43 };
  44
  45 struct bench_dso {
  46         struct list_head        list;
  47         char                    *name;
  48         int                     ino;
  49 };
  50
  51 static int nr_dsos;
  52 static struct bench_dso *dsos;
  53
  54 extern int cmd_inject(int argc, const char *argv[]);
  55
  56 static const struct option options[] = {
  57         OPT_UINTEGER('i', "iterations", &iterations,
  58                      "Number of iterations used to compute average (default: 100)"),
  59         OPT_UINTEGER('m', "nr-mmaps", &nr_mmaps,
  60                      "Number of mmap events for each iteration (default: 100)"),
  61         OPT_UINTEGER('n', "nr-samples", &nr_samples,
  62                      "Number of sample events per mmap event (default: 100)"),
  63         OPT_INCR('v', "verbose", &verbose,
  64                  "be more verbose (show iteration count, DSO name, etc)"),
  65         OPT_END()
  66 };
  67
  68 static const char *const bench_usage[] = {
  69         "perf bench internals inject-build-id <options>",
  70         NULL
  71 };
  72
  73 /*
  74  * Helper for collect_dso that adds the given file as a dso to dso_list
  75  * if it contains a build-id.  Stops after collecting 4 times more than
  76  * we need (for MMAP2 events).
  77  */
  78 static int add_dso(const char *fpath, const struct stat *sb __maybe_unused,
  79                    int typeflag, struct FTW *ftwbuf __maybe_unused)
  80 {
  81         struct bench_dso *dso = &dsos[nr_dsos];
  82         struct build_id bid;
  83
  84         if (typeflag == FTW_D || typeflag == FTW_SL)
  85                 return 0;
  86
  87         if (filename__read_build_id(fpath, &bid) < 0)
  88                 return 0;
  89
  90         dso->name = realpath(fpath, NULL);
  91         if (dso->name == NULL)
  92                 return -1;
  93
  94         dso->ino = nr_dsos++;
  95         pr_debug2("  Adding DSO: %s\n", fpath);
  96
  97         /* stop if we collected enough DSOs */
  98         if ((unsigned int)nr_dsos == DSO_MMAP_RATIO * nr_mmaps)
  99                 return 1;
 100
 101         return 0;
 102 }
 103
 104 static void collect_dso(void)
 105 {
 106         dsos = calloc(nr_mmaps * DSO_MMAP_RATIO, sizeof(*dsos));
 107         if (dsos == NULL) {
 108                 printf("  Memory allocation failed\n");
 109                 exit(1);
 110         }
 111
 112         if (nftw("/usr/lib/", add_dso, 10, FTW_PHYS) < 0)
 113                 return;
 114
 115         pr_debug("  Collected %d DSOs\n", nr_dsos);
 116 }
 117
 118 static void release_dso(void)
 119 {
 120         int i;
 121
 122         for (i = 0; i < nr_dsos; i++) {
 123                 struct bench_dso *dso = &dsos[i];
 124
 125                 free(dso->name);
 126         }
 127         free(dsos);
 128 }
 129
 130 /* Fake address used by mmap and sample events */
 131 static u64 dso_map_addr(struct bench_dso *dso)
 132 {
 133         return 0x400000ULL + dso->ino * 8192ULL;
 134 }
 135
 136 static ssize_t synthesize_attr(struct bench_data *data)
 137 {
 138         union perf_event event;
 139
 140         memset(&event, 0, sizeof(event.attr) + sizeof(u64));
 141
 142         event.header.type = PERF_RECORD_HEADER_ATTR;
 143         event.header.size = sizeof(event.attr) + sizeof(u64);
 144
 145         event.attr.attr.type = PERF_TYPE_SOFTWARE;
 146         event.attr.attr.config = PERF_COUNT_SW_TASK_CLOCK;
 147         event.attr.attr.exclude_kernel = 1;
 148         event.attr.attr.sample_id_all = 1;
 149         event.attr.attr.sample_type = bench_sample_type;
 150
 151         return writen(data->input_pipe[1], &event, event.header.size);
 152 }
 153
 154 static ssize_t synthesize_fork(struct bench_data *data)
 155 {
 156         union perf_event event;
 157
 158         memset(&event, 0, sizeof(event.fork) + bench_id_hdr_size);
 159
 160         event.header.type = PERF_RECORD_FORK;
 161         event.header.misc = PERF_RECORD_MISC_FORK_EXEC;
 162         event.header.size = sizeof(event.fork) + bench_id_hdr_size;
 163
 164         event.fork.ppid = 1;
 165         event.fork.ptid = 1;
 166         event.fork.pid = data->pid;
 167         event.fork.tid = data->pid;
 168
 169         return writen(data->input_pipe[1], &event, event.header.size);
 170 }
 171
 172 static ssize_t synthesize_mmap(struct bench_data *data, struct bench_dso *dso, u64 timestamp)
 173 {
 174         union perf_event event;
 175         size_t len = offsetof(struct perf_record_mmap2, filename);
 176         u64 *id_hdr_ptr = (void *)&event;
 177         int ts_idx;
 178
 179         len += roundup(strlen(dso->name) + 1, 8) + bench_id_hdr_size;
 180
 181         memset(&event, 0, min(len, sizeof(event.mmap2)));
 182
 183         event.header.type = PERF_RECORD_MMAP2;
 184         event.header.misc = PERF_RECORD_MISC_USER;
 185         event.header.size = len;
 186
 187         event.mmap2.pid = data->pid;
 188         event.mmap2.tid = data->pid;
 189         event.mmap2.maj = MMAP_DEV_MAJOR;
 190         event.mmap2.ino = dso->ino;
 191
 192         strcpy(event.mmap2.filename, dso->name);
 193
 194         event.mmap2.start = dso_map_addr(dso);
 195         event.mmap2.len = 4096;
 196         event.mmap2.prot = PROT_EXEC;
 197
 198         if (len > sizeof(event.mmap2)) {
 199                 /* write mmap2 event first */
 200                 if (writen(data->input_pipe[1], &event, len - bench_id_hdr_size) < 0)
 201                         return -1;
 202                 /* zero-fill sample id header */
 203                 memset(id_hdr_ptr, 0, bench_id_hdr_size);
 204                 /* put timestamp in the right position */
 205                 ts_idx = (bench_id_hdr_size / sizeof(u64)) - 2;
 206                 id_hdr_ptr[ts_idx] = timestamp;
 207                 if (writen(data->input_pipe[1], id_hdr_ptr, bench_id_hdr_size) < 0)
 208                         return -1;
 209
 210                 return len;
 211         }
 212
 213         ts_idx = (len / sizeof(u64)) - 2;
 214         id_hdr_ptr[ts_idx] = timestamp;
 215         return writen(data->input_pipe[1], &event, len);
 216 }
 217
 218 static ssize_t synthesize_sample(struct bench_data *data, struct bench_dso *dso, u64 timestamp)
 219 {
 220         union perf_event event;
 221         struct perf_sample sample = {
 222                 .tid = data->pid,
 223                 .pid = data->pid,
 224                 .ip = dso_map_addr(dso),
 225                 .time = timestamp,
 226         };
 227
 228         event.header.type = PERF_RECORD_SAMPLE;
 229         event.header.misc = PERF_RECORD_MISC_USER;
 230         event.header.size = perf_event__sample_event_size(&sample, bench_sample_type, 0);
 231
 232         perf_event__synthesize_sample(&event, bench_sample_type, 0, &sample);
 233
 234         return writen(data->input_pipe[1], &event, event.header.size);
 235 }
 236
 237 static ssize_t synthesize_flush(struct bench_data *data)
 238 {
 239         struct perf_event_header header = {
 240                 .size = sizeof(header),
 241                 .type = PERF_RECORD_FINISHED_ROUND,
 242         };
 243
 244         return writen(data->input_pipe[1], &header, header.size);
 245 }
 246
 247 static void *data_reader(void *arg)
 248 {
 249         struct bench_data *data = arg;
 250         char buf[8192];
 251         int flag;
 252         int n;
 253
 254         flag = fcntl(data->output_pipe[0], F_GETFL);
 255         fcntl(data->output_pipe[0], F_SETFL, flag | O_NONBLOCK);
 256
 257         /* read out data from child */
 258         while (true) {
 259                 n = read(data->output_pipe[0], buf, sizeof(buf));
 260                 if (n > 0)
 261                         continue;
 262                 if (n == 0)
 263                         break;
 264
 265                 if (errno != EINTR && errno != EAGAIN)
 266                         break;
 267
 268                 usleep(100);
 269         }
 270
 271         close(data->output_pipe[0]);
 272         return NULL;
 273 }
 274
 275 static int setup_injection(struct bench_data *data, bool build_id_all)
 276 {
 277         int ready_pipe[2];
 278         int dev_null_fd;
 279         char buf;
 280
 281         if (pipe(ready_pipe) < 0)
 282                 return -1;
 283
 284         if (pipe(data->input_pipe) < 0)
 285                 return -1;
 286
 287         if (pipe(data->output_pipe) < 0)
 288                 return -1;
 289
 290         data->pid = fork();
 291         if (data->pid < 0)
 292                 return -1;
 293
 294         if (data->pid == 0) {
 295                 const char **inject_argv;
 296                 int inject_argc = 2;
 297
 298                 close(data->input_pipe[1]);
 299                 close(data->output_pipe[0]);
 300                 close(ready_pipe[0]);
 301
 302                 dup2(data->input_pipe[0], STDIN_FILENO);
 303                 close(data->input_pipe[0]);
 304                 dup2(data->output_pipe[1], STDOUT_FILENO);
 305                 close(data->output_pipe[1]);
 306
 307                 dev_null_fd = open("/dev/null", O_WRONLY);
 308                 if (dev_null_fd < 0)
 309                         exit(1);
 310
 311                 dup2(dev_null_fd, STDERR_FILENO);
 312
 313                 if (build_id_all)
 314                         inject_argc++;
 315
 316                 inject_argv = calloc(inject_argc + 1, sizeof(*inject_argv));
 317                 if (inject_argv == NULL)
 318                         exit(1);
 319
 320                 inject_argv[0] = strdup("inject");
 321                 inject_argv[1] = strdup("-b");
 322                 if (build_id_all)
 323                         inject_argv[2] = strdup("--buildid-all");
 324
 325                 /* signal that we're ready to go */
 326                 close(ready_pipe[1]);
 327
 328                 cmd_inject(inject_argc, inject_argv);
 329
 330                 exit(0);
 331         }
 332
 333         pthread_create(&data->th, NULL, data_reader, data);
 334
 335         close(ready_pipe[1]);
 336         close(data->input_pipe[0]);
 337         close(data->output_pipe[1]);
 338
 339         /* wait for child ready */
 340         if (read(ready_pipe[0], &buf, 1) < 0)
 341                 return -1;
 342         close(ready_pipe[0]);
 343
 344         return 0;
 345 }
 346
 347 static int inject_build_id(struct bench_data *data, u64 *max_rss)
 348 {
 349         int status;
 350         unsigned int i, k;
 351         struct rusage rusage;
 352
 353         /* this makes the child to run */
 354         if (perf_header__write_pipe(data->input_pipe[1]) < 0)
 355                 return -1;
 356
 357         if (synthesize_attr(data) < 0)
 358                 return -1;
 359
 360         if (synthesize_fork(data) < 0)
 361                 return -1;
 362
 363         for (i = 0; i < nr_mmaps; i++) {
 364                 int idx = rand() % (nr_dsos - 1);
 365                 struct bench_dso *dso = &dsos[idx];
 366                 u64 timestamp = rand() % 1000000;
 367
 368                 pr_debug2("   [%d] injecting: %s\n", i+1, dso->name);
 369                 if (synthesize_mmap(data, dso, timestamp) < 0)
 370                         return -1;
 371
 372                 for (k = 0; k < nr_samples; k++) {
 373                         if (synthesize_sample(data, dso, timestamp + k * 1000) < 0)
 374                                 return -1;
 375                 }
 376
 377                 if ((i + 1) % 10 == 0) {
 378                         if (synthesize_flush(data) < 0)
 379                                 return -1;
 380                 }
 381         }
 382
 383         /* this makes the child to finish */
 384         close(data->input_pipe[1]);
 385
 386         wait4(data->pid, &status, 0, &rusage);
 387         *max_rss = rusage.ru_maxrss;
 388
 389         pr_debug("   Child %d exited with %d\n", data->pid, status);
 390
 391         return 0;
 392 }
 393
 394 static void do_inject_loop(struct bench_data *data, bool build_id_all)
 395 {
 396         unsigned int i;
 397         struct stats time_stats, mem_stats;
 398         double time_average, time_stddev;
 399         double mem_average, mem_stddev;
 400
 401         init_stats(&time_stats);
 402         init_stats(&mem_stats);
 403
 404         pr_debug("  Build-id%s injection benchmark\n", build_id_all ? "-all" : "");
 405
 406         for (i = 0; i < iterations; i++) {
 407                 struct timeval start, end, diff;
 408                 u64 runtime_us, max_rss;
 409
 410                 pr_debug("  Iteration #%d\n", i+1);
 411
 412                 if (setup_injection(data, build_id_all) < 0) {
 413                         printf("  Build-id injection setup failed\n");
 414                         break;
 415                 }
 416
 417                 gettimeofday(&start, NULL);
 418                 if (inject_build_id(data, &max_rss) < 0) {
 419                         printf("  Build-id injection failed\n");
 420                         break;
 421                 }
 422
 423                 gettimeofday(&end, NULL);
 424                 timersub(&end, &start, &diff);
 425                 runtime_us = diff.tv_sec * USEC_PER_SEC + diff.tv_usec;
 426                 update_stats(&time_stats, runtime_us);
 427                 update_stats(&mem_stats, max_rss);
 428
 429                 pthread_join(data->th, NULL);
 430         }
 431
 432         time_average = avg_stats(&time_stats) / USEC_PER_MSEC;
 433         time_stddev = stddev_stats(&time_stats) / USEC_PER_MSEC;
 434         printf("  Average build-id%s injection took: %.3f msec (+- %.3f msec)\n",
 435                build_id_all ? "-all" : "", time_average, time_stddev);
 436
 437         /* each iteration, it processes MMAP2 + BUILD_ID + nr_samples * SAMPLE */
 438         time_average = avg_stats(&time_stats) / (nr_mmaps * (nr_samples + 2));
 439         time_stddev = stddev_stats(&time_stats) / (nr_mmaps * (nr_samples + 2));
 440         printf("  Average time per event: %.3f usec (+- %.3f usec)\n",
 441                 time_average, time_stddev);
 442
 443         mem_average = avg_stats(&mem_stats);
 444         mem_stddev = stddev_stats(&mem_stats);
 445         printf("  Average memory usage: %.0f KB (+- %.0f KB)\n",
 446                 mem_average, mem_stddev);
 447 }
 448
 449 static int do_inject_loops(struct bench_data *data)
 450 {
 451
 452         srand(time(NULL));
 453         symbol__init(NULL);
 454
 455         bench_sample_type  = PERF_SAMPLE_IDENTIFIER | PERF_SAMPLE_IP;
 456         bench_sample_type |= PERF_SAMPLE_TID | PERF_SAMPLE_TIME;
 457         bench_id_hdr_size  = 32;
 458
 459         collect_dso();
 460         if (nr_dsos == 0) {
 461                 printf("  Cannot collect DSOs for injection\n");
 462                 return -1;
 463         }
 464
 465         do_inject_loop(data, false);
 466         do_inject_loop(data, true);
 467
 468         release_dso();
 469         return 0;
 470 }
 471
 472 int bench_inject_build_id(int argc, const char **argv)
 473 {
 474         struct bench_data data;
 475
 476         argc = parse_options(argc, argv, options, bench_usage, 0);
 477         if (argc) {
 478                 usage_with_options(bench_usage, options);
 479                 exit(EXIT_FAILURE);
 480         }
 481
 482         return do_inject_loops(&data);
 483 }
 484