linux/tools/perf/bench/inject-buildid.c
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   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
  31static unsigned int iterations = 100;
  32static unsigned int nr_mmaps   = 100;
  33static unsigned int nr_samples = 100;  /* samples per mmap */
  34
  35static u64 bench_sample_type;
  36static u16 bench_id_hdr_size;
  37
  38struct bench_data {
  39        int                     pid;
  40        int                     input_pipe[2];
  41        int                     output_pipe[2];
  42        pthread_t               th;
  43};
  44
  45struct bench_dso {
  46        struct list_head        list;
  47        char                    *name;
  48        int                     ino;
  49};
  50
  51static int nr_dsos;
  52static struct bench_dso *dsos;
  53
  54extern int cmd_inject(int argc, const char *argv[]);
  55
  56static 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
  68static 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 */
  78static 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
 104static 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
 118static 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 */
 131static u64 dso_map_addr(struct bench_dso *dso)
 132{
 133        return 0x400000ULL + dso->ino * 8192ULL;
 134}
 135
 136static 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
 154static 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
 172static 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
 218static 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
 237static 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
 247static 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
 275static 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
 347static 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
 394static 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
 449static 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
 472int 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
 485