1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * JSON export. 4 * 5 * Copyright (C) 2021, CodeWeavers Inc. <nfraser@codeweavers.com> 6 */ 7 8 #include "data-convert.h" 9 10 #include <fcntl.h> 11 #include <inttypes.h> 12 #include <sys/stat.h> 13 #include <unistd.h> 14 15 #include "linux/compiler.h" 16 #include "linux/err.h" 17 #include "util/auxtrace.h" 18 #include "util/debug.h" 19 #include "util/dso.h" 20 #include "util/event.h" 21 #include "util/evsel.h" 22 #include "util/evlist.h" 23 #include "util/header.h" 24 #include "util/map.h" 25 #include "util/session.h" 26 #include "util/symbol.h" 27 #include "util/thread.h" 28 #include "util/time-utils.h" 29 #include "util/tool.h" 30 31 #ifdef HAVE_LIBTRACEEVENT 32 #include <event-parse.h> 33 #endif 34 35 struct convert_json { 36 struct perf_tool tool; 37 FILE *out; 38 bool first; 39 struct perf_time_interval *ptime_range; 40 int range_size; 41 int range_num; 42 43 u64 events_count; 44 u64 skipped; 45 }; 46 47 // Outputs a JSON-encoded string surrounded by quotes with characters escaped. 48 static void output_json_string(FILE *out, const char *s) 49 { 50 fputc('"', out); 51 while (*s) { 52 switch (*s) { 53 54 // required escapes with special forms as per RFC 8259 55 case '"': fputs("\\\"", out); break; 56 case '\\': fputs("\\\\", out); break; 57 case '\b': fputs("\\b", out); break; 58 case '\f': fputs("\\f", out); break; 59 case '\n': fputs("\\n", out); break; 60 case '\r': fputs("\\r", out); break; 61 case '\t': fputs("\\t", out); break; 62 63 default: 64 // all other control characters must be escaped by hex code 65 if (*s <= 0x1f) 66 fprintf(out, "\\u%04x", *s); 67 else 68 fputc(*s, out); 69 break; 70 } 71 72 ++s; 73 } 74 fputc('"', out); 75 } 76 77 // Outputs an optional comma, newline and indentation to delimit a new value 78 // from the previous one in a JSON object or array. 79 static void output_json_delimiters(FILE *out, bool comma, int depth) 80 { 81 int i; 82 83 if (comma) 84 fputc(',', out); 85 fputc('\n', out); 86 for (i = 0; i < depth; ++i) 87 fputc('\t', out); 88 } 89 90 // Outputs a printf format string (with delimiter) as a JSON value. 91 __printf(4, 5) 92 static void output_json_format(FILE *out, bool comma, int depth, const char *format, ...) 93 { 94 va_list args; 95 96 output_json_delimiters(out, comma, depth); 97 va_start(args, format); 98 vfprintf(out, format, args); 99 va_end(args); 100 } 101 102 // Outputs a JSON key-value pair where the value is a string. 103 static void output_json_key_string(FILE *out, bool comma, int depth, 104 const char *key, const char *value) 105 { 106 output_json_delimiters(out, comma, depth); 107 output_json_string(out, key); 108 fputs(": ", out); 109 output_json_string(out, value); 110 } 111 112 // Outputs a JSON key-value pair where the value is a printf format string. 113 __printf(5, 6) 114 static void output_json_key_format(FILE *out, bool comma, int depth, 115 const char *key, const char *format, ...) 116 { 117 va_list args; 118 119 output_json_delimiters(out, comma, depth); 120 output_json_string(out, key); 121 fputs(": ", out); 122 va_start(args, format); 123 vfprintf(out, format, args); 124 va_end(args); 125 } 126 127 static void output_sample_callchain_entry(const struct perf_tool *tool, 128 u64 ip, struct addr_location *al) 129 { 130 struct convert_json *c = container_of(tool, struct convert_json, tool); 131 FILE *out = c->out; 132 133 output_json_format(out, false, 4, "{"); 134 output_json_key_format(out, false, 5, "ip", "\"0x%" PRIx64 "\"", ip); 135 136 if (al && al->sym && al->sym->namelen) { 137 struct dso *dso = al->map ? map__dso(al->map) : NULL; 138 139 fputc(',', out); 140 output_json_key_string(out, false, 5, "symbol", al->sym->name); 141 142 if (dso) { 143 const char *dso_name = dso__short_name(dso); 144 145 if (dso_name && strlen(dso_name) > 0) { 146 fputc(',', out); 147 output_json_key_string(out, false, 5, "dso", dso_name); 148 } 149 } 150 } 151 152 output_json_format(out, false, 4, "}"); 153 } 154 155 static int process_sample_event(const struct perf_tool *tool, 156 union perf_event *event __maybe_unused, 157 struct perf_sample *sample, 158 struct evsel *evsel __maybe_unused, 159 struct machine *machine) 160 { 161 struct convert_json *c = container_of(tool, struct convert_json, tool); 162 FILE *out = c->out; 163 struct addr_location al; 164 u64 sample_type = __evlist__combined_sample_type(evsel->evlist); 165 u8 cpumode = PERF_RECORD_MISC_USER; 166 167 addr_location__init(&al); 168 if (machine__resolve(machine, &al, sample) < 0) { 169 pr_err("Sample resolution failed!\n"); 170 addr_location__exit(&al); 171 return -1; 172 } 173 174 if (perf_time__ranges_skip_sample(c->ptime_range, c->range_num, sample->time)) { 175 ++c->skipped; 176 return 0; 177 } 178 179 ++c->events_count; 180 181 if (c->first) 182 c->first = false; 183 else 184 fputc(',', out); 185 output_json_format(out, false, 2, "{"); 186 187 output_json_key_format(out, false, 3, "timestamp", "%" PRIi64, sample->time); 188 output_json_key_format(out, true, 3, "pid", "%i", thread__pid(al.thread)); 189 output_json_key_format(out, true, 3, "tid", "%i", thread__tid(al.thread)); 190 191 if ((sample_type & PERF_SAMPLE_CPU)) 192 output_json_key_format(out, true, 3, "cpu", "%i", sample->cpu); 193 else if (thread__cpu(al.thread) >= 0) 194 output_json_key_format(out, true, 3, "cpu", "%i", thread__cpu(al.thread)); 195 196 output_json_key_string(out, true, 3, "comm", thread__comm_str(al.thread)); 197 198 output_json_key_format(out, true, 3, "callchain", "["); 199 if (sample->callchain) { 200 unsigned int i; 201 bool ok; 202 bool first_callchain = true; 203 204 for (i = 0; i < sample->callchain->nr; ++i) { 205 u64 ip = sample->callchain->ips[i]; 206 struct addr_location tal; 207 208 if (ip >= PERF_CONTEXT_MAX) { 209 switch (ip) { 210 case PERF_CONTEXT_HV: 211 cpumode = PERF_RECORD_MISC_HYPERVISOR; 212 break; 213 case PERF_CONTEXT_KERNEL: 214 cpumode = PERF_RECORD_MISC_KERNEL; 215 break; 216 case PERF_CONTEXT_USER: 217 cpumode = PERF_RECORD_MISC_USER; 218 break; 219 default: 220 pr_debug("invalid callchain context: %" 221 PRId64 "\n", (s64) ip); 222 break; 223 } 224 continue; 225 } 226 227 if (first_callchain) 228 first_callchain = false; 229 else 230 fputc(',', out); 231 232 addr_location__init(&tal); 233 ok = thread__find_symbol(al.thread, cpumode, ip, &tal); 234 output_sample_callchain_entry(tool, ip, ok ? &tal : NULL); 235 addr_location__exit(&tal); 236 } 237 } else { 238 output_sample_callchain_entry(tool, sample->ip, &al); 239 } 240 output_json_format(out, false, 3, "]"); 241 242 #ifdef HAVE_LIBTRACEEVENT 243 if (sample->raw_data) { 244 struct tep_event *tp_format = evsel__tp_format(evsel); 245 struct tep_format_field **fields = tp_format ? tep_event_fields(tp_format) : NULL; 246 247 if (fields) { 248 int i = 0; 249 250 while (fields[i]) { 251 struct trace_seq s; 252 253 trace_seq_init(&s); 254 tep_print_field(&s, sample->raw_data, fields[i]); 255 output_json_key_string(out, true, 3, fields[i]->name, s.buffer); 256 257 i++; 258 } 259 free(fields); 260 } 261 } 262 #endif 263 output_json_format(out, false, 2, "}"); 264 addr_location__exit(&al); 265 return 0; 266 } 267 268 static void output_headers(struct perf_session *session, struct convert_json *c) 269 { 270 struct stat st; 271 const struct perf_header *header = &session->header; 272 const struct perf_env *env = perf_session__env(session); 273 int ret; 274 int fd = perf_data__fd(session->data); 275 int i; 276 FILE *out = c->out; 277 278 output_json_key_format(out, false, 2, "header-version", "%u", header->version); 279 280 ret = fstat(fd, &st); 281 if (ret >= 0) { 282 time_t stctime = st.st_mtime; 283 char buf[256]; 284 285 strftime(buf, sizeof(buf), "%FT%TZ", gmtime(&stctime)); 286 output_json_key_string(out, true, 2, "captured-on", buf); 287 } else { 288 pr_debug("Failed to get mtime of source file, not writing captured-on"); 289 } 290 291 output_json_key_format(out, true, 2, "data-offset", "%" PRIu64, header->data_offset); 292 output_json_key_format(out, true, 2, "data-size", "%" PRIu64, header->data_size); 293 output_json_key_format(out, true, 2, "feat-offset", "%" PRIu64, header->feat_offset); 294 295 output_json_key_string(out, true, 2, "hostname", env->hostname); 296 output_json_key_string(out, true, 2, "os-release", env->os_release); 297 output_json_key_string(out, true, 2, "arch", env->arch); 298 299 if (env->cpu_desc) 300 output_json_key_string(out, true, 2, "cpu-desc", env->cpu_desc); 301 302 output_json_key_string(out, true, 2, "cpuid", env->cpuid); 303 output_json_key_format(out, true, 2, "nrcpus-online", "%u", env->nr_cpus_online); 304 output_json_key_format(out, true, 2, "nrcpus-avail", "%u", env->nr_cpus_avail); 305 306 if (env->clock.enabled) { 307 output_json_key_format(out, true, 2, "clockid", 308 "%u", env->clock.clockid); 309 output_json_key_format(out, true, 2, "clock-time", 310 "%" PRIu64, env->clock.clockid_ns); 311 output_json_key_format(out, true, 2, "real-time", 312 "%" PRIu64, env->clock.tod_ns); 313 } 314 315 output_json_key_string(out, true, 2, "perf-version", env->version); 316 317 output_json_key_format(out, true, 2, "cmdline", "["); 318 for (i = 0; i < env->nr_cmdline; i++) { 319 output_json_delimiters(out, i != 0, 3); 320 output_json_string(c->out, env->cmdline_argv[i]); 321 } 322 output_json_format(out, false, 2, "]"); 323 } 324 325 int bt_convert__perf2json(const char *input_name, const char *output_name, 326 struct perf_data_convert_opts *opts __maybe_unused) 327 { 328 struct perf_session *session; 329 int fd; 330 int ret = -1; 331 struct convert_json c = { 332 .first = true, 333 .events_count = 0, 334 .ptime_range = NULL, 335 .range_size = 0, 336 .range_num = 0, 337 .skipped = 0, 338 }; 339 struct perf_data data = { 340 .mode = PERF_DATA_MODE_READ, 341 .path = input_name, 342 .force = opts->force, 343 }; 344 345 perf_tool__init(&c.tool, /*ordered_events=*/true); 346 c.tool.sample = process_sample_event; 347 c.tool.mmap = perf_event__process_mmap; 348 c.tool.mmap2 = perf_event__process_mmap2; 349 c.tool.comm = perf_event__process_comm; 350 c.tool.namespaces = perf_event__process_namespaces; 351 c.tool.cgroup = perf_event__process_cgroup; 352 c.tool.exit = perf_event__process_exit; 353 c.tool.fork = perf_event__process_fork; 354 c.tool.lost = perf_event__process_lost; 355 #ifdef HAVE_LIBTRACEEVENT 356 c.tool.tracing_data = perf_event__process_tracing_data; 357 #endif 358 c.tool.build_id = perf_event__process_build_id; 359 c.tool.id_index = perf_event__process_id_index; 360 c.tool.auxtrace_info = perf_event__process_auxtrace_info; 361 c.tool.auxtrace = perf_event__process_auxtrace; 362 c.tool.event_update = perf_event__process_event_update; 363 c.tool.ordering_requires_timestamps = true; 364 365 if (opts->all) { 366 pr_err("--all is currently unsupported for JSON output.\n"); 367 goto err; 368 } 369 if (opts->tod) { 370 pr_err("--tod is currently unsupported for JSON output.\n"); 371 goto err; 372 } 373 374 fd = open(output_name, O_CREAT | O_WRONLY | (opts->force ? O_TRUNC : O_EXCL), 0666); 375 if (fd == -1) { 376 if (errno == EEXIST) 377 pr_err("Output file exists. Use --force to overwrite it.\n"); 378 else 379 pr_err("Error opening output file!\n"); 380 goto err; 381 } 382 383 c.out = fdopen(fd, "w"); 384 if (!c.out) { 385 fprintf(stderr, "Error opening output file!\n"); 386 close(fd); 387 goto err; 388 } 389 390 session = perf_session__new(&data, &c.tool); 391 if (IS_ERR(session)) { 392 fprintf(stderr, "Error creating perf session!\n"); 393 goto err_fclose; 394 } 395 if (symbol__init(perf_session__env(session)) < 0) { 396 fprintf(stderr, "Symbol init error!\n"); 397 goto err_session_delete; 398 } 399 400 if (opts->time_str) { 401 ret = perf_time__parse_for_ranges(opts->time_str, session, 402 &c.ptime_range, 403 &c.range_size, 404 &c.range_num); 405 if (ret < 0) 406 goto err_session_delete; 407 } 408 409 // The opening brace is printed manually because it isn't delimited from a 410 // previous value (i.e. we don't want a leading newline) 411 fputc('{', c.out); 412 413 // Version number for future-proofing. Most additions should be able to be 414 // done in a backwards-compatible way so this should only need to be bumped 415 // if some major breaking change must be made. 416 output_json_format(c.out, false, 1, "\"linux-perf-json-version\": 1"); 417 418 // Output headers 419 output_json_format(c.out, true, 1, "\"headers\": {"); 420 output_headers(session, &c); 421 output_json_format(c.out, false, 1, "}"); 422 423 // Output samples 424 output_json_format(c.out, true, 1, "\"samples\": ["); 425 perf_session__process_events(session); 426 output_json_format(c.out, false, 1, "]"); 427 output_json_format(c.out, false, 0, "}"); 428 fputc('\n', c.out); 429 430 fprintf(stderr, "[ perf data convert: Converted '%s' into JSON data '%s' ]\n", 431 data.path, output_name); 432 433 fprintf(stderr, 434 "[ perf data convert: Converted and wrote %.3f MB (%" PRIu64 " samples) ]\n", 435 (ftell(c.out)) / 1024.0 / 1024.0, c.events_count); 436 437 if (c.skipped) { 438 fprintf(stderr, "[ perf data convert: Skipped %" PRIu64 " samples ]\n", 439 c.skipped); 440 } 441 442 ret = 0; 443 444 if (c.ptime_range) 445 zfree(&c.ptime_range); 446 447 err_session_delete: 448 perf_session__delete(session); 449 err_fclose: 450 fclose(c.out); 451 err: 452 return ret; 453 } 454