1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira <bristot@kernel.org> 4 */ 5 6 #include <getopt.h> 7 #include <stdlib.h> 8 #include <string.h> 9 #include <signal.h> 10 #include <unistd.h> 11 #include <stdio.h> 12 #include <time.h> 13 14 #include "utils.h" 15 #include "osnoise.h" 16 #include "timerlat.h" 17 18 struct timerlat_top_params { 19 char *cpus; 20 char *monitored_cpus; 21 char *trace_output; 22 unsigned long long runtime; 23 long long stop_us; 24 long long stop_total_us; 25 long long timerlat_period_us; 26 long long print_stack; 27 int sleep_time; 28 int output_divisor; 29 int duration; 30 int quiet; 31 int set_sched; 32 struct sched_attr sched_param; 33 }; 34 35 struct timerlat_top_cpu { 36 int irq_count; 37 int thread_count; 38 39 unsigned long long cur_irq; 40 unsigned long long min_irq; 41 unsigned long long sum_irq; 42 unsigned long long max_irq; 43 44 unsigned long long cur_thread; 45 unsigned long long min_thread; 46 unsigned long long sum_thread; 47 unsigned long long max_thread; 48 }; 49 50 struct timerlat_top_data { 51 struct timerlat_top_cpu *cpu_data; 52 int nr_cpus; 53 }; 54 55 /* 56 * timerlat_free_top - free runtime data 57 */ 58 static void 59 timerlat_free_top(struct timerlat_top_data *data) 60 { 61 free(data->cpu_data); 62 free(data); 63 } 64 65 /* 66 * timerlat_alloc_histogram - alloc runtime data 67 */ 68 static struct timerlat_top_data *timerlat_alloc_top(int nr_cpus) 69 { 70 struct timerlat_top_data *data; 71 int cpu; 72 73 data = calloc(1, sizeof(*data)); 74 if (!data) 75 return NULL; 76 77 data->nr_cpus = nr_cpus; 78 79 /* one set of histograms per CPU */ 80 data->cpu_data = calloc(1, sizeof(*data->cpu_data) * nr_cpus); 81 if (!data->cpu_data) 82 goto cleanup; 83 84 /* set the min to max */ 85 for (cpu = 0; cpu < nr_cpus; cpu++) { 86 data->cpu_data[cpu].min_irq = ~0; 87 data->cpu_data[cpu].min_thread = ~0; 88 } 89 90 return data; 91 92 cleanup: 93 timerlat_free_top(data); 94 return NULL; 95 } 96 97 /* 98 * timerlat_hist_update - record a new timerlat occurent on cpu, updating data 99 */ 100 static void 101 timerlat_top_update(struct osnoise_tool *tool, int cpu, 102 unsigned long long thread, 103 unsigned long long latency) 104 { 105 struct timerlat_top_data *data = tool->data; 106 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu]; 107 108 if (!thread) { 109 cpu_data->irq_count++; 110 cpu_data->cur_irq = latency; 111 update_min(&cpu_data->min_irq, &latency); 112 update_sum(&cpu_data->sum_irq, &latency); 113 update_max(&cpu_data->max_irq, &latency); 114 } else { 115 cpu_data->thread_count++; 116 cpu_data->cur_thread = latency; 117 update_min(&cpu_data->min_thread, &latency); 118 update_sum(&cpu_data->sum_thread, &latency); 119 update_max(&cpu_data->max_thread, &latency); 120 } 121 } 122 123 /* 124 * timerlat_top_handler - this is the handler for timerlat tracer events 125 */ 126 static int 127 timerlat_top_handler(struct trace_seq *s, struct tep_record *record, 128 struct tep_event *event, void *context) 129 { 130 struct trace_instance *trace = context; 131 unsigned long long latency, thread; 132 struct osnoise_tool *top; 133 int cpu = record->cpu; 134 135 top = container_of(trace, struct osnoise_tool, trace); 136 137 tep_get_field_val(s, event, "context", record, &thread, 1); 138 tep_get_field_val(s, event, "timer_latency", record, &latency, 1); 139 140 timerlat_top_update(top, cpu, thread, latency); 141 142 return 0; 143 } 144 145 /* 146 * timerlat_top_header - print the header of the tool output 147 */ 148 static void timerlat_top_header(struct osnoise_tool *top) 149 { 150 struct timerlat_top_params *params = top->params; 151 struct trace_seq *s = top->trace.seq; 152 char duration[26]; 153 154 get_duration(top->start_time, duration, sizeof(duration)); 155 156 trace_seq_printf(s, "\033[2;37;40m"); 157 trace_seq_printf(s, " Timer Latency "); 158 trace_seq_printf(s, "\033[0;0;0m"); 159 trace_seq_printf(s, "\n"); 160 161 trace_seq_printf(s, "%-6s | IRQ Timer Latency (%s) | Thread Timer Latency (%s)\n", duration, 162 params->output_divisor == 1 ? "ns" : "us", 163 params->output_divisor == 1 ? "ns" : "us"); 164 165 trace_seq_printf(s, "\033[2;30;47m"); 166 trace_seq_printf(s, "CPU COUNT | cur min avg max | cur min avg max"); 167 trace_seq_printf(s, "\033[0;0;0m"); 168 trace_seq_printf(s, "\n"); 169 } 170 171 /* 172 * timerlat_top_print - prints the output of a given CPU 173 */ 174 static void timerlat_top_print(struct osnoise_tool *top, int cpu) 175 { 176 177 struct timerlat_top_params *params = top->params; 178 struct timerlat_top_data *data = top->data; 179 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu]; 180 int divisor = params->output_divisor; 181 struct trace_seq *s = top->trace.seq; 182 183 if (divisor == 0) 184 return; 185 186 /* 187 * Skip if no data is available: is this cpu offline? 188 */ 189 if (!cpu_data->irq_count && !cpu_data->thread_count) 190 return; 191 192 /* 193 * Unless trace is being lost, IRQ counter is always the max. 194 */ 195 trace_seq_printf(s, "%3d #%-9d |", cpu, cpu_data->irq_count); 196 197 if (!cpu_data->irq_count) { 198 trace_seq_printf(s, " - "); 199 trace_seq_printf(s, " - "); 200 trace_seq_printf(s, " - "); 201 trace_seq_printf(s, " - |"); 202 } else { 203 trace_seq_printf(s, "%9llu ", cpu_data->cur_irq / params->output_divisor); 204 trace_seq_printf(s, "%9llu ", cpu_data->min_irq / params->output_divisor); 205 trace_seq_printf(s, "%9llu ", (cpu_data->sum_irq / cpu_data->irq_count) / divisor); 206 trace_seq_printf(s, "%9llu |", cpu_data->max_irq / divisor); 207 } 208 209 if (!cpu_data->thread_count) { 210 trace_seq_printf(s, " - "); 211 trace_seq_printf(s, " - "); 212 trace_seq_printf(s, " - "); 213 trace_seq_printf(s, " -\n"); 214 } else { 215 trace_seq_printf(s, "%9llu ", cpu_data->cur_thread / divisor); 216 trace_seq_printf(s, "%9llu ", cpu_data->min_thread / divisor); 217 trace_seq_printf(s, "%9llu ", 218 (cpu_data->sum_thread / cpu_data->thread_count) / divisor); 219 trace_seq_printf(s, "%9llu\n", cpu_data->max_thread / divisor); 220 } 221 } 222 223 /* 224 * clear_terminal - clears the output terminal 225 */ 226 static void clear_terminal(struct trace_seq *seq) 227 { 228 if (!config_debug) 229 trace_seq_printf(seq, "\033c"); 230 } 231 232 /* 233 * timerlat_print_stats - print data for all cpus 234 */ 235 static void 236 timerlat_print_stats(struct timerlat_top_params *params, struct osnoise_tool *top) 237 { 238 struct trace_instance *trace = &top->trace; 239 static int nr_cpus = -1; 240 int i; 241 242 if (nr_cpus == -1) 243 nr_cpus = sysconf(_SC_NPROCESSORS_CONF); 244 245 if (!params->quiet) 246 clear_terminal(trace->seq); 247 248 timerlat_top_header(top); 249 250 for (i = 0; i < nr_cpus; i++) { 251 if (params->cpus && !params->monitored_cpus[i]) 252 continue; 253 timerlat_top_print(top, i); 254 } 255 256 trace_seq_do_printf(trace->seq); 257 trace_seq_reset(trace->seq); 258 } 259 260 /* 261 * timerlat_top_usage - prints timerlat top usage message 262 */ 263 static void timerlat_top_usage(char *usage) 264 { 265 int i; 266 267 static const char *const msg[] = { 268 "", 269 " usage: rtla timerlat [top] [-h] [-q] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] [-t[=file]] \\", 270 " [-c cpu-list] [-P priority]", 271 "", 272 " -h/--help: print this menu", 273 " -p/--period us: timerlat period in us", 274 " -i/--irq us: stop trace if the irq latency is higher than the argument in us", 275 " -T/--thread us: stop trace if the thread latency is higher than the argument in us", 276 " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us", 277 " -c/--cpus cpus: run the tracer only on the given cpus", 278 " -d/--duration time[m|h|d]: duration of the session in seconds", 279 " -D/--debug: print debug info", 280 " -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]", 281 " -n/--nano: display data in nanoseconds", 282 " -q/--quiet print only a summary at the end", 283 " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters", 284 " o:prio - use SCHED_OTHER with prio", 285 " r:prio - use SCHED_RR with prio", 286 " f:prio - use SCHED_FIFO with prio", 287 " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period", 288 " in nanoseconds", 289 NULL, 290 }; 291 292 if (usage) 293 fprintf(stderr, "%s\n", usage); 294 295 fprintf(stderr, "rtla timerlat top: a per-cpu summary of the timer latency (version %s)\n", 296 VERSION); 297 298 for (i = 0; msg[i]; i++) 299 fprintf(stderr, "%s\n", msg[i]); 300 exit(1); 301 } 302 303 /* 304 * timerlat_top_parse_args - allocs, parse and fill the cmd line parameters 305 */ 306 static struct timerlat_top_params 307 *timerlat_top_parse_args(int argc, char **argv) 308 { 309 struct timerlat_top_params *params; 310 int retval; 311 int c; 312 313 params = calloc(1, sizeof(*params)); 314 if (!params) 315 exit(1); 316 317 /* display data in microseconds */ 318 params->output_divisor = 1000; 319 320 while (1) { 321 static struct option long_options[] = { 322 {"cpus", required_argument, 0, 'c'}, 323 {"debug", no_argument, 0, 'D'}, 324 {"duration", required_argument, 0, 'd'}, 325 {"help", no_argument, 0, 'h'}, 326 {"irq", required_argument, 0, 'i'}, 327 {"nano", no_argument, 0, 'n'}, 328 {"period", required_argument, 0, 'p'}, 329 {"priority", required_argument, 0, 'P'}, 330 {"quiet", no_argument, 0, 'q'}, 331 {"stack", required_argument, 0, 's'}, 332 {"thread", required_argument, 0, 'T'}, 333 {"trace", optional_argument, 0, 't'}, 334 {0, 0, 0, 0} 335 }; 336 337 /* getopt_long stores the option index here. */ 338 int option_index = 0; 339 340 c = getopt_long(argc, argv, "c:d:Dhi:np:P:qs:t::T:", 341 long_options, &option_index); 342 343 /* detect the end of the options. */ 344 if (c == -1) 345 break; 346 347 switch (c) { 348 case 'c': 349 retval = parse_cpu_list(optarg, ¶ms->monitored_cpus); 350 if (retval) 351 timerlat_top_usage("\nInvalid -c cpu list\n"); 352 params->cpus = optarg; 353 break; 354 case 'D': 355 config_debug = 1; 356 break; 357 case 'd': 358 params->duration = parse_seconds_duration(optarg); 359 if (!params->duration) 360 timerlat_top_usage("Invalid -D duration\n"); 361 break; 362 case 'h': 363 case '?': 364 timerlat_top_usage(NULL); 365 break; 366 case 'i': 367 params->stop_us = get_llong_from_str(optarg); 368 break; 369 case 'n': 370 params->output_divisor = 1; 371 break; 372 case 'p': 373 params->timerlat_period_us = get_llong_from_str(optarg); 374 if (params->timerlat_period_us > 1000000) 375 timerlat_top_usage("Period longer than 1 s\n"); 376 break; 377 case 'P': 378 retval = parse_prio(optarg, ¶ms->sched_param); 379 if (retval == -1) 380 timerlat_top_usage("Invalid -P priority"); 381 params->set_sched = 1; 382 break; 383 case 'q': 384 params->quiet = 1; 385 break; 386 case 's': 387 params->print_stack = get_llong_from_str(optarg); 388 break; 389 case 'T': 390 params->stop_total_us = get_llong_from_str(optarg); 391 break; 392 case 't': 393 if (optarg) 394 /* skip = */ 395 params->trace_output = &optarg[1]; 396 else 397 params->trace_output = "timerlat_trace.txt"; 398 break; 399 default: 400 timerlat_top_usage("Invalid option"); 401 } 402 } 403 404 if (geteuid()) { 405 err_msg("rtla needs root permission\n"); 406 exit(EXIT_FAILURE); 407 } 408 409 return params; 410 } 411 412 /* 413 * timerlat_top_apply_config - apply the top configs to the initialized tool 414 */ 415 static int 416 timerlat_top_apply_config(struct osnoise_tool *top, struct timerlat_top_params *params) 417 { 418 int retval; 419 420 if (!params->sleep_time) 421 params->sleep_time = 1; 422 423 if (params->cpus) { 424 retval = osnoise_set_cpus(top->context, params->cpus); 425 if (retval) { 426 err_msg("Failed to apply CPUs config\n"); 427 goto out_err; 428 } 429 } 430 431 if (params->stop_us) { 432 retval = osnoise_set_stop_us(top->context, params->stop_us); 433 if (retval) { 434 err_msg("Failed to set stop us\n"); 435 goto out_err; 436 } 437 } 438 439 if (params->stop_total_us) { 440 retval = osnoise_set_stop_total_us(top->context, params->stop_total_us); 441 if (retval) { 442 err_msg("Failed to set stop total us\n"); 443 goto out_err; 444 } 445 } 446 447 448 if (params->timerlat_period_us) { 449 retval = osnoise_set_timerlat_period_us(top->context, params->timerlat_period_us); 450 if (retval) { 451 err_msg("Failed to set timerlat period\n"); 452 goto out_err; 453 } 454 } 455 456 457 if (params->print_stack) { 458 retval = osnoise_set_print_stack(top->context, params->print_stack); 459 if (retval) { 460 err_msg("Failed to set print stack\n"); 461 goto out_err; 462 } 463 } 464 465 return 0; 466 467 out_err: 468 return -1; 469 } 470 471 /* 472 * timerlat_init_top - initialize a timerlat top tool with parameters 473 */ 474 static struct osnoise_tool 475 *timerlat_init_top(struct timerlat_top_params *params) 476 { 477 struct osnoise_tool *top; 478 int nr_cpus; 479 480 nr_cpus = sysconf(_SC_NPROCESSORS_CONF); 481 482 top = osnoise_init_tool("timerlat_top"); 483 if (!top) 484 return NULL; 485 486 top->data = timerlat_alloc_top(nr_cpus); 487 if (!top->data) 488 goto out_err; 489 490 top->params = params; 491 492 tep_register_event_handler(top->trace.tep, -1, "ftrace", "timerlat", 493 timerlat_top_handler, top); 494 495 return top; 496 497 out_err: 498 osnoise_destroy_tool(top); 499 return NULL; 500 } 501 502 static int stop_tracing; 503 static void stop_top(int sig) 504 { 505 stop_tracing = 1; 506 } 507 508 /* 509 * timerlat_top_set_signals - handles the signal to stop the tool 510 */ 511 static void 512 timerlat_top_set_signals(struct timerlat_top_params *params) 513 { 514 signal(SIGINT, stop_top); 515 if (params->duration) { 516 signal(SIGALRM, stop_top); 517 alarm(params->duration); 518 } 519 } 520 521 int timerlat_top_main(int argc, char *argv[]) 522 { 523 struct timerlat_top_params *params; 524 struct trace_instance *trace; 525 struct osnoise_tool *record; 526 struct osnoise_tool *top; 527 int return_value = 1; 528 int retval; 529 530 params = timerlat_top_parse_args(argc, argv); 531 if (!params) 532 exit(1); 533 534 top = timerlat_init_top(params); 535 if (!top) { 536 err_msg("Could not init osnoise top\n"); 537 goto out_exit; 538 } 539 540 retval = timerlat_top_apply_config(top, params); 541 if (retval) { 542 err_msg("Could not apply config\n"); 543 goto out_top; 544 } 545 546 trace = &top->trace; 547 548 retval = enable_timerlat(trace); 549 if (retval) { 550 err_msg("Failed to enable timerlat tracer\n"); 551 goto out_top; 552 } 553 554 if (params->set_sched) { 555 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param); 556 if (retval) { 557 err_msg("Failed to set sched parameters\n"); 558 goto out_top; 559 } 560 } 561 562 trace_instance_start(trace); 563 564 if (params->trace_output) { 565 record = osnoise_init_trace_tool("timerlat"); 566 if (!record) { 567 err_msg("Failed to enable the trace instance\n"); 568 goto out_top; 569 } 570 trace_instance_start(&record->trace); 571 } 572 573 top->start_time = time(NULL); 574 timerlat_top_set_signals(params); 575 576 while (!stop_tracing) { 577 sleep(params->sleep_time); 578 579 retval = tracefs_iterate_raw_events(trace->tep, 580 trace->inst, 581 NULL, 582 0, 583 collect_registered_events, 584 trace); 585 if (retval < 0) { 586 err_msg("Error iterating on events\n"); 587 goto out_top; 588 } 589 590 if (!params->quiet) 591 timerlat_print_stats(params, top); 592 593 if (!tracefs_trace_is_on(trace->inst)) 594 break; 595 596 }; 597 598 timerlat_print_stats(params, top); 599 600 return_value = 0; 601 602 if (!tracefs_trace_is_on(trace->inst)) { 603 printf("rtla timelat hit stop tracing\n"); 604 if (params->trace_output) { 605 printf(" Saving trace to %s\n", params->trace_output); 606 save_trace_to_file(record->trace.inst, params->trace_output); 607 } 608 } 609 610 out_top: 611 timerlat_free_top(top->data); 612 osnoise_destroy_tool(top); 613 if (params->trace_output) 614 osnoise_destroy_tool(record); 615 free(params); 616 out_exit: 617 exit(return_value); 618 } 619