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 u32 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 u32 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 u32 synthesize_mmap(struct bench_data *data, struct bench_dso *dso,
 173                           u64 timestamp)
 174{
 175        union perf_event event;
 176        size_t len = offsetof(struct perf_record_mmap2, filename);
 177        u64 *id_hdr_ptr = (void *)&event;
 178        int ts_idx;
 179
 180        len += roundup(strlen(dso->name) + 1, 8) + bench_id_hdr_size;
 181
 182        memset(&event, 0, min(len, sizeof(event.mmap2)));
 183
 184        event.header.type = PERF_RECORD_MMAP2;
 185        event.header.misc = PERF_RECORD_MISC_USER;
 186        event.header.size = len;
 187
 188        event.mmap2.pid = data->pid;
 189        event.mmap2.tid = data->pid;
 190        event.mmap2.maj = MMAP_DEV_MAJOR;
 191        event.mmap2.ino = dso->ino;
 192
 193        strcpy(event.mmap2.filename, dso->name);
 194
 195        event.mmap2.start = dso_map_addr(dso);
 196        event.mmap2.len = 4096;
 197        event.mmap2.prot = PROT_EXEC;
 198
 199        if (len > sizeof(event.mmap2)) {
 200                /* write mmap2 event first */
 201                writen(data->input_pipe[1], &event, len - bench_id_hdr_size);
 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                writen(data->input_pipe[1], id_hdr_ptr, bench_id_hdr_size);
 208        } else {
 209                ts_idx = (len / sizeof(u64)) - 2;
 210                id_hdr_ptr[ts_idx] = timestamp;
 211                writen(data->input_pipe[1], &event, len);
 212        }
 213        return len;
 214}
 215
 216static u32 synthesize_sample(struct bench_data *data, struct bench_dso *dso,
 217                             u64 timestamp)
 218{
 219        union perf_event event;
 220        struct perf_sample sample = {
 221                .tid = data->pid,
 222                .pid = data->pid,
 223                .ip = dso_map_addr(dso),
 224                .time = timestamp,
 225        };
 226
 227        event.header.type = PERF_RECORD_SAMPLE;
 228        event.header.misc = PERF_RECORD_MISC_USER;
 229        event.header.size = perf_event__sample_event_size(&sample, bench_sample_type, 0);
 230
 231        perf_event__synthesize_sample(&event, bench_sample_type, 0, &sample);
 232
 233        return writen(data->input_pipe[1], &event, event.header.size);
 234}
 235
 236static u32 synthesize_flush(struct bench_data *data)
 237{
 238        struct perf_event_header header = {
 239                .size = sizeof(header),
 240                .type = PERF_RECORD_FINISHED_ROUND,
 241        };
 242
 243        return writen(data->input_pipe[1], &header, header.size);
 244}
 245
 246static void *data_reader(void *arg)
 247{
 248        struct bench_data *data = arg;
 249        char buf[8192];
 250        int flag;
 251        int n;
 252
 253        flag = fcntl(data->output_pipe[0], F_GETFL);
 254        fcntl(data->output_pipe[0], F_SETFL, flag | O_NONBLOCK);
 255
 256        /* read out data from child */
 257        while (true) {
 258                n = read(data->output_pipe[0], buf, sizeof(buf));
 259                if (n > 0)
 260                        continue;
 261                if (n == 0)
 262                        break;
 263
 264                if (errno != EINTR && errno != EAGAIN)
 265                        break;
 266
 267                usleep(100);
 268        }
 269
 270        close(data->output_pipe[0]);
 271        return NULL;
 272}
 273
 274static int setup_injection(struct bench_data *data, bool build_id_all)
 275{
 276        int ready_pipe[2];
 277        int dev_null_fd;
 278        char buf;
 279
 280        if (pipe(ready_pipe) < 0)
 281                return -1;
 282
 283        if (pipe(data->input_pipe) < 0)
 284                return -1;
 285
 286        if (pipe(data->output_pipe) < 0)
 287                return -1;
 288
 289        data->pid = fork();
 290        if (data->pid < 0)
 291                return -1;
 292
 293        if (data->pid == 0) {
 294                const char **inject_argv;
 295                int inject_argc = 2;
 296
 297                close(data->input_pipe[1]);
 298                close(data->output_pipe[0]);
 299                close(ready_pipe[0]);
 300
 301                dup2(data->input_pipe[0], STDIN_FILENO);
 302                close(data->input_pipe[0]);
 303                dup2(data->output_pipe[1], STDOUT_FILENO);
 304                close(data->output_pipe[1]);
 305
 306                dev_null_fd = open("/dev/null", O_WRONLY);
 307                if (dev_null_fd < 0)
 308                        exit(1);
 309
 310                dup2(dev_null_fd, STDERR_FILENO);
 311
 312                if (build_id_all)
 313                        inject_argc++;
 314
 315                inject_argv = calloc(inject_argc + 1, sizeof(*inject_argv));
 316                if (inject_argv == NULL)
 317                        exit(1);
 318
 319                inject_argv[0] = strdup("inject");
 320                inject_argv[1] = strdup("-b");
 321                if (build_id_all)
 322                        inject_argv[2] = strdup("--buildid-all");
 323
 324                /* signal that we're ready to go */
 325                close(ready_pipe[1]);
 326
 327                cmd_inject(inject_argc, inject_argv);
 328
 329                exit(0);
 330        }
 331
 332        pthread_create(&data->th, NULL, data_reader, data);
 333
 334        close(ready_pipe[1]);
 335        close(data->input_pipe[0]);
 336        close(data->output_pipe[1]);
 337
 338        /* wait for child ready */
 339        if (read(ready_pipe[0], &buf, 1) < 0)
 340                return -1;
 341        close(ready_pipe[0]);
 342
 343        return 0;
 344}
 345
 346static int inject_build_id(struct bench_data *data, u64 *max_rss)
 347{
 348        int status;
 349        unsigned int i, k;
 350        struct rusage rusage;
 351        u64 len = 0;
 352
 353        /* this makes the child to run */
 354        if (perf_header__write_pipe(data->input_pipe[1]) < 0)
 355                return -1;
 356
 357        len += synthesize_attr(data);
 358        len += synthesize_fork(data);
 359
 360        for (i = 0; i < nr_mmaps; i++) {
 361                int idx = rand() % (nr_dsos - 1);
 362                struct bench_dso *dso = &dsos[idx];
 363                u64 timestamp = rand() % 1000000;
 364
 365                pr_debug2("   [%d] injecting: %s\n", i+1, dso->name);
 366                len += synthesize_mmap(data, dso, timestamp);
 367
 368                for (k = 0; k < nr_samples; k++)
 369                        len += synthesize_sample(data, dso, timestamp + k * 1000);
 370
 371                if ((i + 1) % 10 == 0)
 372                        len += synthesize_flush(data);
 373        }
 374
 375        /* this makes the child to finish */
 376        close(data->input_pipe[1]);
 377
 378        wait4(data->pid, &status, 0, &rusage);
 379        *max_rss = rusage.ru_maxrss;
 380
 381        pr_debug("   Child %d exited with %d\n", data->pid, status);
 382
 383        return 0;
 384}
 385
 386static void do_inject_loop(struct bench_data *data, bool build_id_all)
 387{
 388        unsigned int i;
 389        struct stats time_stats, mem_stats;
 390        double time_average, time_stddev;
 391        double mem_average, mem_stddev;
 392
 393        init_stats(&time_stats);
 394        init_stats(&mem_stats);
 395
 396        pr_debug("  Build-id%s injection benchmark\n", build_id_all ? "-all" : "");
 397
 398        for (i = 0; i < iterations; i++) {
 399                struct timeval start, end, diff;
 400                u64 runtime_us, max_rss;
 401
 402                pr_debug("  Iteration #%d\n", i+1);
 403
 404                if (setup_injection(data, build_id_all) < 0) {
 405                        printf("  Build-id injection setup failed\n");
 406                        break;
 407                }
 408
 409                gettimeofday(&start, NULL);
 410                if (inject_build_id(data, &max_rss) < 0) {
 411                        printf("  Build-id injection failed\n");
 412                        break;
 413                }
 414
 415                gettimeofday(&end, NULL);
 416                timersub(&end, &start, &diff);
 417                runtime_us = diff.tv_sec * USEC_PER_SEC + diff.tv_usec;
 418                update_stats(&time_stats, runtime_us);
 419                update_stats(&mem_stats, max_rss);
 420
 421                pthread_join(data->th, NULL);
 422        }
 423
 424        time_average = avg_stats(&time_stats) / USEC_PER_MSEC;
 425        time_stddev = stddev_stats(&time_stats) / USEC_PER_MSEC;
 426        printf("  Average build-id%s injection took: %.3f msec (+- %.3f msec)\n",
 427               build_id_all ? "-all" : "", time_average, time_stddev);
 428
 429        /* each iteration, it processes MMAP2 + BUILD_ID + nr_samples * SAMPLE */
 430        time_average = avg_stats(&time_stats) / (nr_mmaps * (nr_samples + 2));
 431        time_stddev = stddev_stats(&time_stats) / (nr_mmaps * (nr_samples + 2));
 432        printf("  Average time per event: %.3f usec (+- %.3f usec)\n",
 433                time_average, time_stddev);
 434
 435        mem_average = avg_stats(&mem_stats);
 436        mem_stddev = stddev_stats(&mem_stats);
 437        printf("  Average memory usage: %.0f KB (+- %.0f KB)\n",
 438                mem_average, mem_stddev);
 439}
 440
 441static int do_inject_loops(struct bench_data *data)
 442{
 443
 444        srand(time(NULL));
 445        symbol__init(NULL);
 446
 447        bench_sample_type  = PERF_SAMPLE_IDENTIFIER | PERF_SAMPLE_IP;
 448        bench_sample_type |= PERF_SAMPLE_TID | PERF_SAMPLE_TIME;
 449        bench_id_hdr_size  = 32;
 450
 451        collect_dso();
 452        if (nr_dsos == 0) {
 453                printf("  Cannot collect DSOs for injection\n");
 454                return -1;
 455        }
 456
 457        do_inject_loop(data, false);
 458        do_inject_loop(data, true);
 459
 460        release_dso();
 461        return 0;
 462}
 463
 464int bench_inject_build_id(int argc, const char **argv)
 465{
 466        struct bench_data data;
 467
 468        argc = parse_options(argc, argv, options, bench_usage, 0);
 469        if (argc) {
 470                usage_with_options(bench_usage, options);
 471                exit(EXIT_FAILURE);
 472        }
 473
 474        return do_inject_loops(&data);
 475}
 476
 477