tools/perf/builtin-script.c

   1 #include "builtin.h"
   2
   3 #include "perf.h"
   4 #include "util/cache.h"
   5 #include "util/debug.h"
   6 #include "util/exec_cmd.h"
   7 #include "util/header.h"
   8 #include "util/parse-options.h"
   9 #include "util/session.h"
  10 #include "util/symbol.h"
  11 #include "util/thread.h"
  12 #include "util/trace-event.h"
  13 #include "util/parse-options.h"
  14 #include "util/util.h"
  15
  16 static char const               *script_name;
  17 static char const               *generate_script_lang;
  18 static bool                     debug_mode;
  19 static u64                      last_timestamp;
  20 static u64                      nr_unordered;
  21 extern const struct option      record_options[];
  22
  23 static int default_start_script(const char *script __unused,
  24                                 int argc __unused,
  25                                 const char **argv __unused)
  26 {
  27         return 0;
  28 }
  29
  30 static int default_stop_script(void)
  31 {
  32         return 0;
  33 }
  34
  35 static int default_generate_script(const char *outfile __unused)
  36 {
  37         return 0;
  38 }
  39
  40 static struct scripting_ops default_scripting_ops = {
  41         .start_script           = default_start_script,
  42         .stop_script            = default_stop_script,
  43         .process_event          = print_event,
  44         .generate_script        = default_generate_script,
  45 };
  46
  47 static struct scripting_ops     *scripting_ops;
  48
  49 static void setup_scripting(void)
  50 {
  51         setup_perl_scripting();
  52         setup_python_scripting();
  53
  54         scripting_ops = &default_scripting_ops;
  55 }
  56
  57 static int cleanup_scripting(void)
  58 {
  59         pr_debug("\nperf script stopped\n");
  60
  61         return scripting_ops->stop_script();
  62 }
  63
  64 static char const               *input_name = "perf.data";
  65
  66 static int process_sample_event(event_t *event, struct sample_data *sample,
  67                                 struct perf_session *session)
  68 {
  69         struct thread *thread = perf_session__findnew(session, event->ip.pid);
  70
  71         if (thread == NULL) {
  72                 pr_debug("problem processing %d event, skipping it.\n",
  73                          event->header.type);
  74                 return -1;
  75         }
  76
  77         if (session->sample_type & PERF_SAMPLE_RAW) {
  78                 if (debug_mode) {
  79                         if (sample->time < last_timestamp) {
  80                                 pr_err("Samples misordered, previous: %" PRIu64
  81                                         " this: %" PRIu64 "\n", last_timestamp,
  82                                         sample->time);
  83                                 nr_unordered++;
  84                         }
  85                         last_timestamp = sample->time;
  86                         return 0;
  87                 }
  88                 /*
  89                  * FIXME: better resolve from pid from the struct trace_entry
  90                  * field, although it should be the same than this perf
  91                  * event pid
  92                  */
  93                 scripting_ops->process_event(sample->cpu, sample->raw_data,
  94                                              sample->raw_size,
  95                                              sample->time, thread->comm);
  96         }
  97
  98         session->hists.stats.total_period += sample->period;
  99         return 0;
 100 }
 101
 102 static struct perf_event_ops event_ops = {
 103         .sample = process_sample_event,
 104         .comm   = event__process_comm,
 105         .attr   = event__process_attr,
 106         .event_type = event__process_event_type,
 107         .tracing_data = event__process_tracing_data,
 108         .build_id = event__process_build_id,
 109         .ordering_requires_timestamps = true,
 110         .ordered_samples = true,
 111 };
 112
 113 extern volatile int session_done;
 114
 115 static void sig_handler(int sig __unused)
 116 {
 117         session_done = 1;
 118 }
 119
 120 static int __cmd_script(struct perf_session *session)
 121 {
 122         int ret;
 123
 124         signal(SIGINT, sig_handler);
 125
 126         ret = perf_session__process_events(session, &event_ops);
 127
 128         if (debug_mode)
 129                 pr_err("Misordered timestamps: %" PRIu64 "\n", nr_unordered);
 130
 131         return ret;
 132 }
 133
 134 struct script_spec {
 135         struct list_head        node;
 136         struct scripting_ops    *ops;
 137         char                    spec[0];
 138 };
 139
 140 static LIST_HEAD(script_specs);
 141
 142 static struct script_spec *script_spec__new(const char *spec,
 143                                             struct scripting_ops *ops)
 144 {
 145         struct script_spec *s = malloc(sizeof(*s) + strlen(spec) + 1);
 146
 147         if (s != NULL) {
 148                 strcpy(s->spec, spec);
 149                 s->ops = ops;
 150         }
 151
 152         return s;
 153 }
 154
 155 static void script_spec__delete(struct script_spec *s)
 156 {
 157         free(s->spec);
 158         free(s);
 159 }
 160
 161 static void script_spec__add(struct script_spec *s)
 162 {
 163         list_add_tail(&s->node, &script_specs);
 164 }
 165
 166 static struct script_spec *script_spec__find(const char *spec)
 167 {
 168         struct script_spec *s;
 169
 170         list_for_each_entry(s, &script_specs, node)
 171                 if (strcasecmp(s->spec, spec) == 0)
 172                         return s;
 173         return NULL;
 174 }
 175
 176 static struct script_spec *script_spec__findnew(const char *spec,
 177                                                 struct scripting_ops *ops)
 178 {
 179         struct script_spec *s = script_spec__find(spec);
 180
 181         if (s)
 182                 return s;
 183
 184         s = script_spec__new(spec, ops);
 185         if (!s)
 186                 goto out_delete_spec;
 187
 188         script_spec__add(s);
 189
 190         return s;
 191
 192 out_delete_spec:
 193         script_spec__delete(s);
 194
 195         return NULL;
 196 }
 197
 198 int script_spec_register(const char *spec, struct scripting_ops *ops)
 199 {
 200         struct script_spec *s;
 201
 202         s = script_spec__find(spec);
 203         if (s)
 204                 return -1;
 205
 206         s = script_spec__findnew(spec, ops);
 207         if (!s)
 208                 return -1;
 209
 210         return 0;
 211 }
 212
 213 static struct scripting_ops *script_spec__lookup(const char *spec)
 214 {
 215         struct script_spec *s = script_spec__find(spec);
 216         if (!s)
 217                 return NULL;
 218
 219         return s->ops;
 220 }
 221
 222 static void list_available_languages(void)
 223 {
 224         struct script_spec *s;
 225
 226         fprintf(stderr, "\n");
 227         fprintf(stderr, "Scripting language extensions (used in "
 228                 "perf script -s [spec:]script.[spec]):\n\n");
 229
 230         list_for_each_entry(s, &script_specs, node)
 231                 fprintf(stderr, "  %-42s [%s]\n", s->spec, s->ops->name);
 232
 233         fprintf(stderr, "\n");
 234 }
 235
 236 static int parse_scriptname(const struct option *opt __used,
 237                             const char *str, int unset __used)
 238 {
 239         char spec[PATH_MAX];
 240         const char *script, *ext;
 241         int len;
 242
 243         if (strcmp(str, "lang") == 0) {
 244                 list_available_languages();
 245                 exit(0);
 246         }
 247
 248         script = strchr(str, ':');
 249         if (script) {
 250                 len = script - str;
 251                 if (len >= PATH_MAX) {
 252                         fprintf(stderr, "invalid language specifier");
 253                         return -1;
 254                 }
 255                 strncpy(spec, str, len);
 256                 spec[len] = '\0';
 257                 scripting_ops = script_spec__lookup(spec);
 258                 if (!scripting_ops) {
 259                         fprintf(stderr, "invalid language specifier");
 260                         return -1;
 261                 }
 262                 script++;
 263         } else {
 264                 script = str;
 265                 ext = strrchr(script, '.');
 266                 if (!ext) {
 267                         fprintf(stderr, "invalid script extension");
 268                         return -1;
 269                 }
 270                 scripting_ops = script_spec__lookup(++ext);
 271                 if (!scripting_ops) {
 272                         fprintf(stderr, "invalid script extension");
 273                         return -1;
 274                 }
 275         }
 276
 277         script_name = strdup(script);
 278
 279         return 0;
 280 }
 281
 282 /* Helper function for filesystems that return a dent->d_type DT_UNKNOWN */
 283 static int is_directory(const char *base_path, const struct dirent *dent)
 284 {
 285         char path[PATH_MAX];
 286         struct stat st;
 287
 288         sprintf(path, "%s/%s", base_path, dent->d_name);
 289         if (stat(path, &st))
 290                 return 0;
 291
 292         return S_ISDIR(st.st_mode);
 293 }
 294
 295 #define for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next)\
 296         while (!readdir_r(scripts_dir, &lang_dirent, &lang_next) &&     \
 297                lang_next)                                               \
 298                 if ((lang_dirent.d_type == DT_DIR ||                    \
 299                      (lang_dirent.d_type == DT_UNKNOWN &&               \
 300                       is_directory(scripts_path, &lang_dirent))) &&     \
 301                     (strcmp(lang_dirent.d_name, ".")) &&                \
 302                     (strcmp(lang_dirent.d_name, "..")))
 303
 304 #define for_each_script(lang_path, lang_dir, script_dirent, script_next)\
 305         while (!readdir_r(lang_dir, &script_dirent, &script_next) &&    \
 306                script_next)                                             \
 307                 if (script_dirent.d_type != DT_DIR &&                   \
 308                     (script_dirent.d_type != DT_UNKNOWN ||              \
 309                      !is_directory(lang_path, &script_dirent)))
 310
 311
 312 #define RECORD_SUFFIX                   "-record"
 313 #define REPORT_SUFFIX                   "-report"
 314
 315 struct script_desc {
 316         struct list_head        node;
 317         char                    *name;
 318         char                    *half_liner;
 319         char                    *args;
 320 };
 321
 322 static LIST_HEAD(script_descs);
 323
 324 static struct script_desc *script_desc__new(const char *name)
 325 {
 326         struct script_desc *s = zalloc(sizeof(*s));
 327
 328         if (s != NULL && name)
 329                 s->name = strdup(name);
 330
 331         return s;
 332 }
 333
 334 static void script_desc__delete(struct script_desc *s)
 335 {
 336         free(s->name);
 337         free(s->half_liner);
 338         free(s->args);
 339         free(s);
 340 }
 341
 342 static void script_desc__add(struct script_desc *s)
 343 {
 344         list_add_tail(&s->node, &script_descs);
 345 }
 346
 347 static struct script_desc *script_desc__find(const char *name)
 348 {
 349         struct script_desc *s;
 350
 351         list_for_each_entry(s, &script_descs, node)
 352                 if (strcasecmp(s->name, name) == 0)
 353                         return s;
 354         return NULL;
 355 }
 356
 357 static struct script_desc *script_desc__findnew(const char *name)
 358 {
 359         struct script_desc *s = script_desc__find(name);
 360
 361         if (s)
 362                 return s;
 363
 364         s = script_desc__new(name);
 365         if (!s)
 366                 goto out_delete_desc;
 367
 368         script_desc__add(s);
 369
 370         return s;
 371
 372 out_delete_desc:
 373         script_desc__delete(s);
 374
 375         return NULL;
 376 }
 377
 378 static const char *ends_with(const char *str, const char *suffix)
 379 {
 380         size_t suffix_len = strlen(suffix);
 381         const char *p = str;
 382
 383         if (strlen(str) > suffix_len) {
 384                 p = str + strlen(str) - suffix_len;
 385                 if (!strncmp(p, suffix, suffix_len))
 386                         return p;
 387         }
 388
 389         return NULL;
 390 }
 391
 392 static char *ltrim(char *str)
 393 {
 394         int len = strlen(str);
 395
 396         while (len && isspace(*str)) {
 397                 len--;
 398                 str++;
 399         }
 400
 401         return str;
 402 }
 403
 404 static int read_script_info(struct script_desc *desc, const char *filename)
 405 {
 406         char line[BUFSIZ], *p;
 407         FILE *fp;
 408
 409         fp = fopen(filename, "r");
 410         if (!fp)
 411                 return -1;
 412
 413         while (fgets(line, sizeof(line), fp)) {
 414                 p = ltrim(line);
 415                 if (strlen(p) == 0)
 416                         continue;
 417                 if (*p != '#')
 418                         continue;
 419                 p++;
 420                 if (strlen(p) && *p == '!')
 421                         continue;
 422
 423                 p = ltrim(p);
 424                 if (strlen(p) && p[strlen(p) - 1] == '\n')
 425                         p[strlen(p) - 1] = '\0';
 426
 427                 if (!strncmp(p, "description:", strlen("description:"))) {
 428                         p += strlen("description:");
 429                         desc->half_liner = strdup(ltrim(p));
 430                         continue;
 431                 }
 432
 433                 if (!strncmp(p, "args:", strlen("args:"))) {
 434                         p += strlen("args:");
 435                         desc->args = strdup(ltrim(p));
 436                         continue;
 437                 }
 438         }
 439
 440         fclose(fp);
 441
 442         return 0;
 443 }
 444
 445 static int list_available_scripts(const struct option *opt __used,
 446                                   const char *s __used, int unset __used)
 447 {
 448         struct dirent *script_next, *lang_next, script_dirent, lang_dirent;
 449         char scripts_path[MAXPATHLEN];
 450         DIR *scripts_dir, *lang_dir;
 451         char script_path[MAXPATHLEN];
 452         char lang_path[MAXPATHLEN];
 453         struct script_desc *desc;
 454         char first_half[BUFSIZ];
 455         char *script_root;
 456         char *str;
 457
 458         snprintf(scripts_path, MAXPATHLEN, "%s/scripts", perf_exec_path());
 459
 460         scripts_dir = opendir(scripts_path);
 461         if (!scripts_dir)
 462                 return -1;
 463
 464         for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next) {
 465                 snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
 466                          lang_dirent.d_name);
 467                 lang_dir = opendir(lang_path);
 468                 if (!lang_dir)
 469                         continue;
 470
 471                 for_each_script(lang_path, lang_dir, script_dirent, script_next) {
 472                         script_root = strdup(script_dirent.d_name);
 473                         str = (char *)ends_with(script_root, REPORT_SUFFIX);
 474                         if (str) {
 475                                 *str = '\0';
 476                                 desc = script_desc__findnew(script_root);
 477                                 snprintf(script_path, MAXPATHLEN, "%s/%s",
 478                                          lang_path, script_dirent.d_name);
 479                                 read_script_info(desc, script_path);
 480                         }
 481                         free(script_root);
 482                 }
 483         }
 484
 485         fprintf(stdout, "List of available trace scripts:\n");
 486         list_for_each_entry(desc, &script_descs, node) {
 487                 sprintf(first_half, "%s %s", desc->name,
 488                         desc->args ? desc->args : "");
 489                 fprintf(stdout, "  %-36s %s\n", first_half,
 490                         desc->half_liner ? desc->half_liner : "");
 491         }
 492
 493         exit(0);
 494 }
 495
 496 static char *get_script_path(const char *script_root, const char *suffix)
 497 {
 498         struct dirent *script_next, *lang_next, script_dirent, lang_dirent;
 499         char scripts_path[MAXPATHLEN];
 500         char script_path[MAXPATHLEN];
 501         DIR *scripts_dir, *lang_dir;
 502         char lang_path[MAXPATHLEN];
 503         char *str, *__script_root;
 504         char *path = NULL;
 505
 506         snprintf(scripts_path, MAXPATHLEN, "%s/scripts", perf_exec_path());
 507
 508         scripts_dir = opendir(scripts_path);
 509         if (!scripts_dir)
 510                 return NULL;
 511
 512         for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next) {
 513                 snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
 514                          lang_dirent.d_name);
 515                 lang_dir = opendir(lang_path);
 516                 if (!lang_dir)
 517                         continue;
 518
 519                 for_each_script(lang_path, lang_dir, script_dirent, script_next) {
 520                         __script_root = strdup(script_dirent.d_name);
 521                         str = (char *)ends_with(__script_root, suffix);
 522                         if (str) {
 523                                 *str = '\0';
 524                                 if (strcmp(__script_root, script_root))
 525                                         continue;
 526                                 snprintf(script_path, MAXPATHLEN, "%s/%s",
 527                                          lang_path, script_dirent.d_name);
 528                                 path = strdup(script_path);
 529                                 free(__script_root);
 530                                 break;
 531                         }
 532                         free(__script_root);
 533                 }
 534         }
 535
 536         return path;
 537 }
 538
 539 static bool is_top_script(const char *script_path)
 540 {
 541         return ends_with(script_path, "top") == NULL ? false : true;
 542 }
 543
 544 static int has_required_arg(char *script_path)
 545 {
 546         struct script_desc *desc;
 547         int n_args = 0;
 548         char *p;
 549
 550         desc = script_desc__new(NULL);
 551
 552         if (read_script_info(desc, script_path))
 553                 goto out;
 554
 555         if (!desc->args)
 556                 goto out;
 557
 558         for (p = desc->args; *p; p++)
 559                 if (*p == '<')
 560                         n_args++;
 561 out:
 562         script_desc__delete(desc);
 563
 564         return n_args;
 565 }
 566
 567 static const char * const script_usage[] = {
 568         "perf script [<options>]",
 569         "perf script [<options>] record <script> [<record-options>] <command>",
 570         "perf script [<options>] report <script> [script-args]",
 571         "perf script [<options>] <script> [<record-options>] <command>",
 572         "perf script [<options>] <top-script> [script-args]",
 573         NULL
 574 };
 575
 576 static const struct option options[] = {
 577         OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 578                     "dump raw trace in ASCII"),
 579         OPT_INCR('v', "verbose", &verbose,
 580                     "be more verbose (show symbol address, etc)"),
 581         OPT_BOOLEAN('L', "Latency", &latency_format,
 582                     "show latency attributes (irqs/preemption disabled, etc)"),
 583         OPT_CALLBACK_NOOPT('l', "list", NULL, NULL, "list available scripts",
 584                            list_available_scripts),
 585         OPT_CALLBACK('s', "script", NULL, "name",
 586                      "script file name (lang:script name, script name, or *)",
 587                      parse_scriptname),
 588         OPT_STRING('g', "gen-script", &generate_script_lang, "lang",
 589                    "generate perf-script.xx script in specified language"),
 590         OPT_STRING('i', "input", &input_name, "file",
 591                     "input file name"),
 592         OPT_BOOLEAN('d', "debug-mode", &debug_mode,
 593                    "do various checks like samples ordering and lost events"),
 594
 595         OPT_END()
 596 };
 597
 598 static bool have_cmd(int argc, const char **argv)
 599 {
 600         char **__argv = malloc(sizeof(const char *) * argc);
 601
 602         if (!__argv)
 603                 die("malloc");
 604         memcpy(__argv, argv, sizeof(const char *) * argc);
 605         argc = parse_options(argc, (const char **)__argv, record_options,
 606                              NULL, PARSE_OPT_STOP_AT_NON_OPTION);
 607         free(__argv);
 608
 609         return argc != 0;
 610 }
 611
 612 int cmd_script(int argc, const char **argv, const char *prefix __used)
 613 {
 614         char *rec_script_path = NULL;
 615         char *rep_script_path = NULL;
 616         struct perf_session *session;
 617         char *script_path = NULL;
 618         const char **__argv;
 619         bool system_wide;
 620         int i, j, err;
 621
 622         setup_scripting();
 623
 624         argc = parse_options(argc, argv, options, script_usage,
 625                              PARSE_OPT_STOP_AT_NON_OPTION);
 626
 627         if (argc > 1 && !strncmp(argv[0], "rec", strlen("rec"))) {
 628                 rec_script_path = get_script_path(argv[1], RECORD_SUFFIX);
 629                 if (!rec_script_path)
 630                         return cmd_record(argc, argv, NULL);
 631         }
 632
 633         if (argc > 1 && !strncmp(argv[0], "rep", strlen("rep"))) {
 634                 rep_script_path = get_script_path(argv[1], REPORT_SUFFIX);
 635                 if (!rep_script_path) {
 636                         fprintf(stderr,
 637                                 "Please specify a valid report script"
 638                                 "(see 'perf script -l' for listing)\n");
 639                         return -1;
 640                 }
 641         }
 642
 643         /* make sure PERF_EXEC_PATH is set for scripts */
 644         perf_set_argv_exec_path(perf_exec_path());
 645
 646         if (argc && !script_name && !rec_script_path && !rep_script_path) {
 647                 int live_pipe[2];
 648                 int rep_args;
 649                 pid_t pid;
 650
 651                 rec_script_path = get_script_path(argv[0], RECORD_SUFFIX);
 652                 rep_script_path = get_script_path(argv[0], REPORT_SUFFIX);
 653
 654                 if (!rec_script_path && !rep_script_path) {
 655                         fprintf(stderr, " Couldn't find script %s\n\n See perf"
 656                                 " script -l for available scripts.\n", argv[0]);
 657                         usage_with_options(script_usage, options);
 658                 }
 659
 660                 if (is_top_script(argv[0])) {
 661                         rep_args = argc - 1;
 662                 } else {
 663                         int rec_args;
 664
 665                         rep_args = has_required_arg(rep_script_path);
 666                         rec_args = (argc - 1) - rep_args;
 667                         if (rec_args < 0) {
 668                                 fprintf(stderr, " %s script requires options."
 669                                         "\n\n See perf script -l for available "
 670                                         "scripts and options.\n", argv[0]);
 671                                 usage_with_options(script_usage, options);
 672                         }
 673                 }
 674
 675                 if (pipe(live_pipe) < 0) {
 676                         perror("failed to create pipe");
 677                         exit(-1);
 678                 }
 679
 680                 pid = fork();
 681                 if (pid < 0) {
 682                         perror("failed to fork");
 683                         exit(-1);
 684                 }
 685
 686                 if (!pid) {
 687                         system_wide = true;
 688                         j = 0;
 689
 690                         dup2(live_pipe[1], 1);
 691                         close(live_pipe[0]);
 692
 693                         if (!is_top_script(argv[0]))
 694                                 system_wide = !have_cmd(argc - rep_args,
 695                                                         &argv[rep_args]);
 696
 697                         __argv = malloc((argc + 6) * sizeof(const char *));
 698                         if (!__argv)
 699                                 die("malloc");
 700
 701                         __argv[j++] = "/bin/sh";
 702                         __argv[j++] = rec_script_path;
 703                         if (system_wide)
 704                                 __argv[j++] = "-a";
 705                         __argv[j++] = "-q";
 706                         __argv[j++] = "-o";
 707                         __argv[j++] = "-";
 708                         for (i = rep_args + 1; i < argc; i++)
 709                                 __argv[j++] = argv[i];
 710                         __argv[j++] = NULL;
 711
 712                         execvp("/bin/sh", (char **)__argv);
 713                         free(__argv);
 714                         exit(-1);
 715                 }
 716
 717                 dup2(live_pipe[0], 0);
 718                 close(live_pipe[1]);
 719
 720                 __argv = malloc((argc + 4) * sizeof(const char *));
 721                 if (!__argv)
 722                         die("malloc");
 723                 j = 0;
 724                 __argv[j++] = "/bin/sh";
 725                 __argv[j++] = rep_script_path;
 726                 for (i = 1; i < rep_args + 1; i++)
 727                         __argv[j++] = argv[i];
 728                 __argv[j++] = "-i";
 729                 __argv[j++] = "-";
 730                 __argv[j++] = NULL;
 731
 732                 execvp("/bin/sh", (char **)__argv);
 733                 free(__argv);
 734                 exit(-1);
 735         }
 736
 737         if (rec_script_path)
 738                 script_path = rec_script_path;
 739         if (rep_script_path)
 740                 script_path = rep_script_path;
 741
 742         if (script_path) {
 743                 system_wide = false;
 744                 j = 0;
 745
 746                 if (rec_script_path)
 747                         system_wide = !have_cmd(argc - 1, &argv[1]);
 748
 749                 __argv = malloc((argc + 2) * sizeof(const char *));
 750                 if (!__argv)
 751                         die("malloc");
 752                 __argv[j++] = "/bin/sh";
 753                 __argv[j++] = script_path;
 754                 if (system_wide)
 755                         __argv[j++] = "-a";
 756                 for (i = 2; i < argc; i++)
 757                         __argv[j++] = argv[i];
 758                 __argv[j++] = NULL;
 759
 760                 execvp("/bin/sh", (char **)__argv);
 761                 free(__argv);
 762                 exit(-1);
 763         }
 764
 765         if (symbol__init() < 0)
 766                 return -1;
 767         if (!script_name)
 768                 setup_pager();
 769
 770         session = perf_session__new(input_name, O_RDONLY, 0, false, &event_ops);
 771         if (session == NULL)
 772                 return -ENOMEM;
 773
 774         if (strcmp(input_name, "-") &&
 775             !perf_session__has_traces(session, "record -R"))
 776                 return -EINVAL;
 777
 778         if (generate_script_lang) {
 779                 struct stat perf_stat;
 780
 781                 int input = open(input_name, O_RDONLY);
 782                 if (input < 0) {
 783                         perror("failed to open file");
 784                         exit(-1);
 785                 }
 786
 787                 err = fstat(input, &perf_stat);
 788                 if (err < 0) {
 789                         perror("failed to stat file");
 790                         exit(-1);
 791                 }
 792
 793                 if (!perf_stat.st_size) {
 794                         fprintf(stderr, "zero-sized file, nothing to do!\n");
 795                         exit(0);
 796                 }
 797
 798                 scripting_ops = script_spec__lookup(generate_script_lang);
 799                 if (!scripting_ops) {
 800                         fprintf(stderr, "invalid language specifier");
 801                         return -1;
 802                 }
 803
 804                 err = scripting_ops->generate_script("perf-script");
 805                 goto out;
 806         }
 807
 808         if (script_name) {
 809                 err = scripting_ops->start_script(script_name, argc, argv);
 810                 if (err)
 811                         goto out;
 812                 pr_debug("perf script started with script %s\n\n", script_name);
 813         }
 814
 815         err = __cmd_script(session);
 816
 817         perf_session__delete(session);
 818         cleanup_scripting();
 819 out:
 820         return err;
 821 }