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 #define _GNU_SOURCE 7 #include <getopt.h> 8 #include <stdlib.h> 9 #include <string.h> 10 #include <signal.h> 11 #include <unistd.h> 12 #include <stdio.h> 13 #include <time.h> 14 #include <errno.h> 15 #include <sched.h> 16 #include <pthread.h> 17 18 #include "utils.h" 19 #include "osnoise.h" 20 #include "timerlat.h" 21 #include "timerlat_aa.h" 22 #include "timerlat_u.h" 23 24 struct timerlat_top_params { 25 char *cpus; 26 cpu_set_t monitored_cpus; 27 char *trace_output; 28 char *cgroup_name; 29 unsigned long long runtime; 30 long long stop_us; 31 long long stop_total_us; 32 long long timerlat_period_us; 33 long long print_stack; 34 int sleep_time; 35 int output_divisor; 36 int duration; 37 int quiet; 38 int set_sched; 39 int dma_latency; 40 int no_aa; 41 int aa_only; 42 int dump_tasks; 43 int cgroup; 44 int hk_cpus; 45 int user_top; 46 cpu_set_t hk_cpu_set; 47 struct sched_attr sched_param; 48 struct trace_events *events; 49 }; 50 51 struct timerlat_top_cpu { 52 int irq_count; 53 int thread_count; 54 int user_count; 55 56 unsigned long long cur_irq; 57 unsigned long long min_irq; 58 unsigned long long sum_irq; 59 unsigned long long max_irq; 60 61 unsigned long long cur_thread; 62 unsigned long long min_thread; 63 unsigned long long sum_thread; 64 unsigned long long max_thread; 65 66 unsigned long long cur_user; 67 unsigned long long min_user; 68 unsigned long long sum_user; 69 unsigned long long max_user; 70 }; 71 72 struct timerlat_top_data { 73 struct timerlat_top_cpu *cpu_data; 74 int nr_cpus; 75 }; 76 77 /* 78 * timerlat_free_top - free runtime data 79 */ 80 static void 81 timerlat_free_top(struct timerlat_top_data *data) 82 { 83 free(data->cpu_data); 84 free(data); 85 } 86 87 /* 88 * timerlat_alloc_histogram - alloc runtime data 89 */ 90 static struct timerlat_top_data *timerlat_alloc_top(int nr_cpus) 91 { 92 struct timerlat_top_data *data; 93 int cpu; 94 95 data = calloc(1, sizeof(*data)); 96 if (!data) 97 return NULL; 98 99 data->nr_cpus = nr_cpus; 100 101 /* one set of histograms per CPU */ 102 data->cpu_data = calloc(1, sizeof(*data->cpu_data) * nr_cpus); 103 if (!data->cpu_data) 104 goto cleanup; 105 106 /* set the min to max */ 107 for (cpu = 0; cpu < nr_cpus; cpu++) { 108 data->cpu_data[cpu].min_irq = ~0; 109 data->cpu_data[cpu].min_thread = ~0; 110 data->cpu_data[cpu].min_user = ~0; 111 } 112 113 return data; 114 115 cleanup: 116 timerlat_free_top(data); 117 return NULL; 118 } 119 120 /* 121 * timerlat_hist_update - record a new timerlat occurent on cpu, updating data 122 */ 123 static void 124 timerlat_top_update(struct osnoise_tool *tool, int cpu, 125 unsigned long long thread, 126 unsigned long long latency) 127 { 128 struct timerlat_top_data *data = tool->data; 129 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu]; 130 131 if (!thread) { 132 cpu_data->irq_count++; 133 cpu_data->cur_irq = latency; 134 update_min(&cpu_data->min_irq, &latency); 135 update_sum(&cpu_data->sum_irq, &latency); 136 update_max(&cpu_data->max_irq, &latency); 137 } else if (thread == 1) { 138 cpu_data->thread_count++; 139 cpu_data->cur_thread = latency; 140 update_min(&cpu_data->min_thread, &latency); 141 update_sum(&cpu_data->sum_thread, &latency); 142 update_max(&cpu_data->max_thread, &latency); 143 } else { 144 cpu_data->user_count++; 145 cpu_data->cur_user = latency; 146 update_min(&cpu_data->min_user, &latency); 147 update_sum(&cpu_data->sum_user, &latency); 148 update_max(&cpu_data->max_user, &latency); 149 } 150 } 151 152 /* 153 * timerlat_top_handler - this is the handler for timerlat tracer events 154 */ 155 static int 156 timerlat_top_handler(struct trace_seq *s, struct tep_record *record, 157 struct tep_event *event, void *context) 158 { 159 struct trace_instance *trace = context; 160 struct timerlat_top_params *params; 161 unsigned long long latency, thread; 162 struct osnoise_tool *top; 163 int cpu = record->cpu; 164 165 top = container_of(trace, struct osnoise_tool, trace); 166 params = top->params; 167 168 if (!params->aa_only) { 169 tep_get_field_val(s, event, "context", record, &thread, 1); 170 tep_get_field_val(s, event, "timer_latency", record, &latency, 1); 171 172 timerlat_top_update(top, cpu, thread, latency); 173 } 174 175 return 0; 176 } 177 178 /* 179 * timerlat_top_header - print the header of the tool output 180 */ 181 static void timerlat_top_header(struct osnoise_tool *top) 182 { 183 struct timerlat_top_params *params = top->params; 184 struct trace_seq *s = top->trace.seq; 185 char duration[26]; 186 187 get_duration(top->start_time, duration, sizeof(duration)); 188 189 trace_seq_printf(s, "\033[2;37;40m"); 190 trace_seq_printf(s, " Timer Latency "); 191 if (params->user_top) 192 trace_seq_printf(s, " "); 193 trace_seq_printf(s, "\033[0;0;0m"); 194 trace_seq_printf(s, "\n"); 195 196 trace_seq_printf(s, "%-6s | IRQ Timer Latency (%s) | Thread Timer Latency (%s)", duration, 197 params->output_divisor == 1 ? "ns" : "us", 198 params->output_divisor == 1 ? "ns" : "us"); 199 200 if (params->user_top) { 201 trace_seq_printf(s, " | Ret user Timer Latency (%s)", 202 params->output_divisor == 1 ? "ns" : "us"); 203 } 204 205 trace_seq_printf(s, "\n"); 206 trace_seq_printf(s, "\033[2;30;47m"); 207 trace_seq_printf(s, "CPU COUNT | cur min avg max | cur min avg max"); 208 if (params->user_top) 209 trace_seq_printf(s, " | cur min avg max"); 210 trace_seq_printf(s, "\033[0;0;0m"); 211 trace_seq_printf(s, "\n"); 212 } 213 214 static const char *no_value = " -"; 215 216 /* 217 * timerlat_top_print - prints the output of a given CPU 218 */ 219 static void timerlat_top_print(struct osnoise_tool *top, int cpu) 220 { 221 222 struct timerlat_top_params *params = top->params; 223 struct timerlat_top_data *data = top->data; 224 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu]; 225 int divisor = params->output_divisor; 226 struct trace_seq *s = top->trace.seq; 227 228 if (divisor == 0) 229 return; 230 231 /* 232 * Skip if no data is available: is this cpu offline? 233 */ 234 if (!cpu_data->irq_count && !cpu_data->thread_count) 235 return; 236 237 /* 238 * Unless trace is being lost, IRQ counter is always the max. 239 */ 240 trace_seq_printf(s, "%3d #%-9d |", cpu, cpu_data->irq_count); 241 242 if (!cpu_data->irq_count) { 243 trace_seq_printf(s, "%s %s %s %s |", no_value, no_value, no_value, no_value); 244 } else { 245 trace_seq_printf(s, "%9llu ", cpu_data->cur_irq / params->output_divisor); 246 trace_seq_printf(s, "%9llu ", cpu_data->min_irq / params->output_divisor); 247 trace_seq_printf(s, "%9llu ", (cpu_data->sum_irq / cpu_data->irq_count) / divisor); 248 trace_seq_printf(s, "%9llu |", cpu_data->max_irq / divisor); 249 } 250 251 if (!cpu_data->thread_count) { 252 trace_seq_printf(s, "%s %s %s %s", no_value, no_value, no_value, no_value); 253 } else { 254 trace_seq_printf(s, "%9llu ", cpu_data->cur_thread / divisor); 255 trace_seq_printf(s, "%9llu ", cpu_data->min_thread / divisor); 256 trace_seq_printf(s, "%9llu ", 257 (cpu_data->sum_thread / cpu_data->thread_count) / divisor); 258 trace_seq_printf(s, "%9llu", cpu_data->max_thread / divisor); 259 } 260 261 if (!params->user_top) { 262 trace_seq_printf(s, "\n"); 263 return; 264 } 265 266 trace_seq_printf(s, " |"); 267 268 if (!cpu_data->user_count) { 269 trace_seq_printf(s, "%s %s %s %s\n", no_value, no_value, no_value, no_value); 270 } else { 271 trace_seq_printf(s, "%9llu ", cpu_data->cur_user / divisor); 272 trace_seq_printf(s, "%9llu ", cpu_data->min_user / divisor); 273 trace_seq_printf(s, "%9llu ", 274 (cpu_data->sum_user / cpu_data->user_count) / divisor); 275 trace_seq_printf(s, "%9llu\n", cpu_data->max_user / divisor); 276 } 277 } 278 279 /* 280 * clear_terminal - clears the output terminal 281 */ 282 static void clear_terminal(struct trace_seq *seq) 283 { 284 if (!config_debug) 285 trace_seq_printf(seq, "\033c"); 286 } 287 288 /* 289 * timerlat_print_stats - print data for all cpus 290 */ 291 static void 292 timerlat_print_stats(struct timerlat_top_params *params, struct osnoise_tool *top) 293 { 294 struct trace_instance *trace = &top->trace; 295 static int nr_cpus = -1; 296 int i; 297 298 if (params->aa_only) 299 return; 300 301 if (nr_cpus == -1) 302 nr_cpus = sysconf(_SC_NPROCESSORS_CONF); 303 304 if (!params->quiet) 305 clear_terminal(trace->seq); 306 307 timerlat_top_header(top); 308 309 for (i = 0; i < nr_cpus; i++) { 310 if (params->cpus && !CPU_ISSET(i, ¶ms->monitored_cpus)) 311 continue; 312 timerlat_top_print(top, i); 313 } 314 315 trace_seq_do_printf(trace->seq); 316 trace_seq_reset(trace->seq); 317 } 318 319 /* 320 * timerlat_top_usage - prints timerlat top usage message 321 */ 322 static void timerlat_top_usage(char *usage) 323 { 324 int i; 325 326 static const char *const msg[] = { 327 "", 328 " usage: rtla timerlat [top] [-h] [-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\", 329 " [[-t[=file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\", 330 " [-P priority] [--dma-latency us] [--aa-only us] [-C[=cgroup_name]] [-u]", 331 "", 332 " -h/--help: print this menu", 333 " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit", 334 " --aa-only us: stop if <us> latency is hit, only printing the auto analysis (reduces CPU usage)", 335 " -p/--period us: timerlat period in us", 336 " -i/--irq us: stop trace if the irq latency is higher than the argument in us", 337 " -T/--thread us: stop trace if the thread latency is higher than the argument in us", 338 " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us", 339 " -c/--cpus cpus: run the tracer only on the given cpus", 340 " -H/--house-keeping cpus: run rtla control threads only on the given cpus", 341 " -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited", 342 " -d/--duration time[s|m|h|d]: duration of the session", 343 " -D/--debug: print debug info", 344 " --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)", 345 " -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]", 346 " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed", 347 " --filter <command>: enable a trace event filter to the previous -e event", 348 " --trigger <command>: enable a trace event trigger to the previous -e event", 349 " -n/--nano: display data in nanoseconds", 350 " --no-aa: disable auto-analysis, reducing rtla timerlat cpu usage", 351 " -q/--quiet print only a summary at the end", 352 " --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency", 353 " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters", 354 " o:prio - use SCHED_OTHER with prio", 355 " r:prio - use SCHED_RR with prio", 356 " f:prio - use SCHED_FIFO with prio", 357 " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period", 358 " in nanoseconds", 359 " -u/--user-threads: use rtla user-space threads instead of in-kernel timerlat threads", 360 NULL, 361 }; 362 363 if (usage) 364 fprintf(stderr, "%s\n", usage); 365 366 fprintf(stderr, "rtla timerlat top: a per-cpu summary of the timer latency (version %s)\n", 367 VERSION); 368 369 for (i = 0; msg[i]; i++) 370 fprintf(stderr, "%s\n", msg[i]); 371 372 if (usage) 373 exit(EXIT_FAILURE); 374 375 exit(EXIT_SUCCESS); 376 } 377 378 /* 379 * timerlat_top_parse_args - allocs, parse and fill the cmd line parameters 380 */ 381 static struct timerlat_top_params 382 *timerlat_top_parse_args(int argc, char **argv) 383 { 384 struct timerlat_top_params *params; 385 struct trace_events *tevent; 386 long long auto_thresh; 387 int retval; 388 int c; 389 390 params = calloc(1, sizeof(*params)); 391 if (!params) 392 exit(1); 393 394 /* disabled by default */ 395 params->dma_latency = -1; 396 397 /* display data in microseconds */ 398 params->output_divisor = 1000; 399 400 while (1) { 401 static struct option long_options[] = { 402 {"auto", required_argument, 0, 'a'}, 403 {"cpus", required_argument, 0, 'c'}, 404 {"cgroup", optional_argument, 0, 'C'}, 405 {"debug", no_argument, 0, 'D'}, 406 {"duration", required_argument, 0, 'd'}, 407 {"event", required_argument, 0, 'e'}, 408 {"help", no_argument, 0, 'h'}, 409 {"house-keeping", required_argument, 0, 'H'}, 410 {"irq", required_argument, 0, 'i'}, 411 {"nano", no_argument, 0, 'n'}, 412 {"period", required_argument, 0, 'p'}, 413 {"priority", required_argument, 0, 'P'}, 414 {"quiet", no_argument, 0, 'q'}, 415 {"stack", required_argument, 0, 's'}, 416 {"thread", required_argument, 0, 'T'}, 417 {"trace", optional_argument, 0, 't'}, 418 {"user-threads", no_argument, 0, 'u'}, 419 {"trigger", required_argument, 0, '0'}, 420 {"filter", required_argument, 0, '1'}, 421 {"dma-latency", required_argument, 0, '2'}, 422 {"no-aa", no_argument, 0, '3'}, 423 {"dump-tasks", no_argument, 0, '4'}, 424 {"aa-only", required_argument, 0, '5'}, 425 {0, 0, 0, 0} 426 }; 427 428 /* getopt_long stores the option index here. */ 429 int option_index = 0; 430 431 c = getopt_long(argc, argv, "a:c:C::d:De:hH:i:np:P:qs:t::T:u0:1:2:345:", 432 long_options, &option_index); 433 434 /* detect the end of the options. */ 435 if (c == -1) 436 break; 437 438 switch (c) { 439 case 'a': 440 auto_thresh = get_llong_from_str(optarg); 441 442 /* set thread stop to auto_thresh */ 443 params->stop_total_us = auto_thresh; 444 params->stop_us = auto_thresh; 445 446 /* get stack trace */ 447 params->print_stack = auto_thresh; 448 449 /* set trace */ 450 params->trace_output = "timerlat_trace.txt"; 451 break; 452 case '5': 453 /* it is here because it is similar to -a */ 454 auto_thresh = get_llong_from_str(optarg); 455 456 /* set thread stop to auto_thresh */ 457 params->stop_total_us = auto_thresh; 458 params->stop_us = auto_thresh; 459 460 /* get stack trace */ 461 params->print_stack = auto_thresh; 462 463 /* set aa_only to avoid parsing the trace */ 464 params->aa_only = 1; 465 break; 466 case 'c': 467 retval = parse_cpu_set(optarg, ¶ms->monitored_cpus); 468 if (retval) 469 timerlat_top_usage("\nInvalid -c cpu list\n"); 470 params->cpus = optarg; 471 break; 472 case 'C': 473 params->cgroup = 1; 474 if (!optarg) { 475 /* will inherit this cgroup */ 476 params->cgroup_name = NULL; 477 } else if (*optarg == '=') { 478 /* skip the = */ 479 params->cgroup_name = ++optarg; 480 } 481 break; 482 case 'D': 483 config_debug = 1; 484 break; 485 case 'd': 486 params->duration = parse_seconds_duration(optarg); 487 if (!params->duration) 488 timerlat_top_usage("Invalid -d duration\n"); 489 break; 490 case 'e': 491 tevent = trace_event_alloc(optarg); 492 if (!tevent) { 493 err_msg("Error alloc trace event"); 494 exit(EXIT_FAILURE); 495 } 496 497 if (params->events) 498 tevent->next = params->events; 499 params->events = tevent; 500 break; 501 case 'h': 502 case '?': 503 timerlat_top_usage(NULL); 504 break; 505 case 'H': 506 params->hk_cpus = 1; 507 retval = parse_cpu_set(optarg, ¶ms->hk_cpu_set); 508 if (retval) { 509 err_msg("Error parsing house keeping CPUs\n"); 510 exit(EXIT_FAILURE); 511 } 512 break; 513 case 'i': 514 params->stop_us = get_llong_from_str(optarg); 515 break; 516 case 'n': 517 params->output_divisor = 1; 518 break; 519 case 'p': 520 params->timerlat_period_us = get_llong_from_str(optarg); 521 if (params->timerlat_period_us > 1000000) 522 timerlat_top_usage("Period longer than 1 s\n"); 523 break; 524 case 'P': 525 retval = parse_prio(optarg, ¶ms->sched_param); 526 if (retval == -1) 527 timerlat_top_usage("Invalid -P priority"); 528 params->set_sched = 1; 529 break; 530 case 'q': 531 params->quiet = 1; 532 break; 533 case 's': 534 params->print_stack = get_llong_from_str(optarg); 535 break; 536 case 'T': 537 params->stop_total_us = get_llong_from_str(optarg); 538 break; 539 case 't': 540 if (optarg) 541 /* skip = */ 542 params->trace_output = &optarg[1]; 543 else 544 params->trace_output = "timerlat_trace.txt"; 545 546 break; 547 case 'u': 548 params->user_top = true; 549 break; 550 case '0': /* trigger */ 551 if (params->events) { 552 retval = trace_event_add_trigger(params->events, optarg); 553 if (retval) { 554 err_msg("Error adding trigger %s\n", optarg); 555 exit(EXIT_FAILURE); 556 } 557 } else { 558 timerlat_top_usage("--trigger requires a previous -e\n"); 559 } 560 break; 561 case '1': /* filter */ 562 if (params->events) { 563 retval = trace_event_add_filter(params->events, optarg); 564 if (retval) { 565 err_msg("Error adding filter %s\n", optarg); 566 exit(EXIT_FAILURE); 567 } 568 } else { 569 timerlat_top_usage("--filter requires a previous -e\n"); 570 } 571 break; 572 case '2': /* dma-latency */ 573 params->dma_latency = get_llong_from_str(optarg); 574 if (params->dma_latency < 0 || params->dma_latency > 10000) { 575 err_msg("--dma-latency needs to be >= 0 and < 10000"); 576 exit(EXIT_FAILURE); 577 } 578 break; 579 case '3': /* no-aa */ 580 params->no_aa = 1; 581 break; 582 case '4': 583 params->dump_tasks = 1; 584 break; 585 default: 586 timerlat_top_usage("Invalid option"); 587 } 588 } 589 590 if (geteuid()) { 591 err_msg("rtla needs root permission\n"); 592 exit(EXIT_FAILURE); 593 } 594 595 /* 596 * Auto analysis only happens if stop tracing, thus: 597 */ 598 if (!params->stop_us && !params->stop_total_us) 599 params->no_aa = 1; 600 601 if (params->no_aa && params->aa_only) 602 timerlat_top_usage("--no-aa and --aa-only are mutually exclusive!"); 603 604 return params; 605 } 606 607 /* 608 * timerlat_top_apply_config - apply the top configs to the initialized tool 609 */ 610 static int 611 timerlat_top_apply_config(struct osnoise_tool *top, struct timerlat_top_params *params) 612 { 613 int retval; 614 int i; 615 616 if (!params->sleep_time) 617 params->sleep_time = 1; 618 619 if (params->cpus) { 620 retval = osnoise_set_cpus(top->context, params->cpus); 621 if (retval) { 622 err_msg("Failed to apply CPUs config\n"); 623 goto out_err; 624 } 625 } else { 626 for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++) 627 CPU_SET(i, ¶ms->monitored_cpus); 628 } 629 630 if (params->stop_us) { 631 retval = osnoise_set_stop_us(top->context, params->stop_us); 632 if (retval) { 633 err_msg("Failed to set stop us\n"); 634 goto out_err; 635 } 636 } 637 638 if (params->stop_total_us) { 639 retval = osnoise_set_stop_total_us(top->context, params->stop_total_us); 640 if (retval) { 641 err_msg("Failed to set stop total us\n"); 642 goto out_err; 643 } 644 } 645 646 647 if (params->timerlat_period_us) { 648 retval = osnoise_set_timerlat_period_us(top->context, params->timerlat_period_us); 649 if (retval) { 650 err_msg("Failed to set timerlat period\n"); 651 goto out_err; 652 } 653 } 654 655 656 if (params->print_stack) { 657 retval = osnoise_set_print_stack(top->context, params->print_stack); 658 if (retval) { 659 err_msg("Failed to set print stack\n"); 660 goto out_err; 661 } 662 } 663 664 if (params->hk_cpus) { 665 retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set), 666 ¶ms->hk_cpu_set); 667 if (retval == -1) { 668 err_msg("Failed to set rtla to the house keeping CPUs\n"); 669 goto out_err; 670 } 671 } else if (params->cpus) { 672 /* 673 * Even if the user do not set a house-keeping CPU, try to 674 * move rtla to a CPU set different to the one where the user 675 * set the workload to run. 676 * 677 * No need to check results as this is an automatic attempt. 678 */ 679 auto_house_keeping(¶ms->monitored_cpus); 680 } 681 682 if (params->user_top) { 683 retval = osnoise_set_workload(top->context, 0); 684 if (retval) { 685 err_msg("Failed to set OSNOISE_WORKLOAD option\n"); 686 goto out_err; 687 } 688 } 689 690 return 0; 691 692 out_err: 693 return -1; 694 } 695 696 /* 697 * timerlat_init_top - initialize a timerlat top tool with parameters 698 */ 699 static struct osnoise_tool 700 *timerlat_init_top(struct timerlat_top_params *params) 701 { 702 struct osnoise_tool *top; 703 int nr_cpus; 704 705 nr_cpus = sysconf(_SC_NPROCESSORS_CONF); 706 707 top = osnoise_init_tool("timerlat_top"); 708 if (!top) 709 return NULL; 710 711 top->data = timerlat_alloc_top(nr_cpus); 712 if (!top->data) 713 goto out_err; 714 715 top->params = params; 716 717 tep_register_event_handler(top->trace.tep, -1, "ftrace", "timerlat", 718 timerlat_top_handler, top); 719 720 return top; 721 722 out_err: 723 osnoise_destroy_tool(top); 724 return NULL; 725 } 726 727 static int stop_tracing; 728 static void stop_top(int sig) 729 { 730 stop_tracing = 1; 731 } 732 733 /* 734 * timerlat_top_set_signals - handles the signal to stop the tool 735 */ 736 static void 737 timerlat_top_set_signals(struct timerlat_top_params *params) 738 { 739 signal(SIGINT, stop_top); 740 if (params->duration) { 741 signal(SIGALRM, stop_top); 742 alarm(params->duration); 743 } 744 } 745 746 int timerlat_top_main(int argc, char *argv[]) 747 { 748 struct timerlat_top_params *params; 749 struct osnoise_tool *record = NULL; 750 struct timerlat_u_params params_u; 751 struct osnoise_tool *top = NULL; 752 struct osnoise_tool *aa = NULL; 753 struct trace_instance *trace; 754 int dma_latency_fd = -1; 755 pthread_t timerlat_u; 756 int return_value = 1; 757 char *max_lat; 758 int retval; 759 760 params = timerlat_top_parse_args(argc, argv); 761 if (!params) 762 exit(1); 763 764 top = timerlat_init_top(params); 765 if (!top) { 766 err_msg("Could not init osnoise top\n"); 767 goto out_exit; 768 } 769 770 retval = timerlat_top_apply_config(top, params); 771 if (retval) { 772 err_msg("Could not apply config\n"); 773 goto out_free; 774 } 775 776 trace = &top->trace; 777 778 retval = enable_timerlat(trace); 779 if (retval) { 780 err_msg("Failed to enable timerlat tracer\n"); 781 goto out_free; 782 } 783 784 if (params->set_sched) { 785 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param); 786 if (retval) { 787 err_msg("Failed to set sched parameters\n"); 788 goto out_free; 789 } 790 } 791 792 if (params->cgroup && !params->user_top) { 793 retval = set_comm_cgroup("timerlat/", params->cgroup_name); 794 if (!retval) { 795 err_msg("Failed to move threads to cgroup\n"); 796 goto out_free; 797 } 798 } 799 800 if (params->dma_latency >= 0) { 801 dma_latency_fd = set_cpu_dma_latency(params->dma_latency); 802 if (dma_latency_fd < 0) { 803 err_msg("Could not set /dev/cpu_dma_latency.\n"); 804 goto out_free; 805 } 806 } 807 808 if (params->trace_output) { 809 record = osnoise_init_trace_tool("timerlat"); 810 if (!record) { 811 err_msg("Failed to enable the trace instance\n"); 812 goto out_free; 813 } 814 815 if (params->events) { 816 retval = trace_events_enable(&record->trace, params->events); 817 if (retval) 818 goto out_top; 819 } 820 } 821 822 if (!params->no_aa) { 823 if (params->aa_only) { 824 /* as top is not used for display, use it for aa */ 825 aa = top; 826 } else { 827 /* otherwise, a new instance is needed */ 828 aa = osnoise_init_tool("timerlat_aa"); 829 if (!aa) 830 goto out_top; 831 } 832 833 retval = timerlat_aa_init(aa, params->dump_tasks); 834 if (retval) { 835 err_msg("Failed to enable the auto analysis instance\n"); 836 goto out_top; 837 } 838 839 /* if it is re-using the main instance, there is no need to start it */ 840 if (aa != top) { 841 retval = enable_timerlat(&aa->trace); 842 if (retval) { 843 err_msg("Failed to enable timerlat tracer\n"); 844 goto out_top; 845 } 846 } 847 } 848 849 /* 850 * Start the tracers here, after having set all instances. 851 * 852 * Let the trace instance start first for the case of hitting a stop 853 * tracing while enabling other instances. The trace instance is the 854 * one with most valuable information. 855 */ 856 if (params->trace_output) 857 trace_instance_start(&record->trace); 858 if (!params->no_aa && aa != top) 859 trace_instance_start(&aa->trace); 860 trace_instance_start(trace); 861 862 top->start_time = time(NULL); 863 timerlat_top_set_signals(params); 864 865 if (params->user_top) { 866 /* rtla asked to stop */ 867 params_u.should_run = 1; 868 /* all threads left */ 869 params_u.stopped_running = 0; 870 871 params_u.set = ¶ms->monitored_cpus; 872 if (params->set_sched) 873 params_u.sched_param = ¶ms->sched_param; 874 else 875 params_u.sched_param = NULL; 876 877 params_u.cgroup_name = params->cgroup_name; 878 879 retval = pthread_create(&timerlat_u, NULL, timerlat_u_dispatcher, ¶ms_u); 880 if (retval) 881 err_msg("Error creating timerlat user-space threads\n"); 882 } 883 884 while (!stop_tracing) { 885 sleep(params->sleep_time); 886 887 if (params->aa_only && !trace_is_off(&top->trace, &record->trace)) 888 continue; 889 890 retval = tracefs_iterate_raw_events(trace->tep, 891 trace->inst, 892 NULL, 893 0, 894 collect_registered_events, 895 trace); 896 if (retval < 0) { 897 err_msg("Error iterating on events\n"); 898 goto out_top; 899 } 900 901 if (!params->quiet) 902 timerlat_print_stats(params, top); 903 904 if (trace_is_off(&top->trace, &record->trace)) 905 break; 906 907 /* is there still any user-threads ? */ 908 if (params->user_top) { 909 if (params_u.stopped_running) { 910 debug_msg("timerlat user space threads stopped!\n"); 911 break; 912 } 913 } 914 } 915 916 if (params->user_top && !params_u.stopped_running) { 917 params_u.should_run = 0; 918 sleep(1); 919 } 920 921 timerlat_print_stats(params, top); 922 923 return_value = 0; 924 925 if (trace_is_off(&top->trace, &record->trace)) { 926 printf("rtla timerlat hit stop tracing\n"); 927 928 if (!params->no_aa) 929 timerlat_auto_analysis(params->stop_us, params->stop_total_us); 930 931 if (params->trace_output) { 932 printf(" Saving trace to %s\n", params->trace_output); 933 save_trace_to_file(record->trace.inst, params->trace_output); 934 } 935 } else if (params->aa_only) { 936 /* 937 * If the trace did not stop with --aa-only, at least print the 938 * max known latency. 939 */ 940 max_lat = tracefs_instance_file_read(trace->inst, "tracing_max_latency", NULL); 941 if (max_lat) { 942 printf(" Max latency was %s\n", max_lat); 943 free(max_lat); 944 } 945 } 946 947 out_top: 948 timerlat_aa_destroy(); 949 if (dma_latency_fd >= 0) 950 close(dma_latency_fd); 951 trace_events_destroy(&record->trace, params->events); 952 params->events = NULL; 953 out_free: 954 timerlat_free_top(top->data); 955 if (aa && aa != top) 956 osnoise_destroy_tool(aa); 957 osnoise_destroy_tool(record); 958 osnoise_destroy_tool(top); 959 free(params); 960 out_exit: 961 exit(return_value); 962 } 963