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 /* 215 * timerlat_top_print - prints the output of a given CPU 216 */ 217 static void timerlat_top_print(struct osnoise_tool *top, int cpu) 218 { 219 220 struct timerlat_top_params *params = top->params; 221 struct timerlat_top_data *data = top->data; 222 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu]; 223 int divisor = params->output_divisor; 224 struct trace_seq *s = top->trace.seq; 225 226 if (divisor == 0) 227 return; 228 229 /* 230 * Skip if no data is available: is this cpu offline? 231 */ 232 if (!cpu_data->irq_count && !cpu_data->thread_count) 233 return; 234 235 /* 236 * Unless trace is being lost, IRQ counter is always the max. 237 */ 238 trace_seq_printf(s, "%3d #%-9d |", cpu, cpu_data->irq_count); 239 240 if (!cpu_data->irq_count) { 241 trace_seq_printf(s, " - "); 242 trace_seq_printf(s, " - "); 243 trace_seq_printf(s, " - "); 244 trace_seq_printf(s, " - |"); 245 } else { 246 trace_seq_printf(s, "%9llu ", cpu_data->cur_irq / params->output_divisor); 247 trace_seq_printf(s, "%9llu ", cpu_data->min_irq / params->output_divisor); 248 trace_seq_printf(s, "%9llu ", (cpu_data->sum_irq / cpu_data->irq_count) / divisor); 249 trace_seq_printf(s, "%9llu |", cpu_data->max_irq / divisor); 250 } 251 252 if (!cpu_data->thread_count) { 253 trace_seq_printf(s, " - "); 254 trace_seq_printf(s, " - "); 255 trace_seq_printf(s, " - "); 256 trace_seq_printf(s, " -\n"); 257 } else { 258 trace_seq_printf(s, "%9llu ", cpu_data->cur_thread / divisor); 259 trace_seq_printf(s, "%9llu ", cpu_data->min_thread / divisor); 260 trace_seq_printf(s, "%9llu ", 261 (cpu_data->sum_thread / cpu_data->thread_count) / divisor); 262 trace_seq_printf(s, "%9llu", cpu_data->max_thread / divisor); 263 } 264 265 if (!params->user_top) { 266 trace_seq_printf(s, "\n"); 267 return; 268 } 269 270 trace_seq_printf(s, " |"); 271 272 if (!cpu_data->user_count) { 273 trace_seq_printf(s, " - "); 274 trace_seq_printf(s, " - "); 275 trace_seq_printf(s, " - "); 276 trace_seq_printf(s, " -\n"); 277 } else { 278 trace_seq_printf(s, "%9llu ", cpu_data->cur_user / divisor); 279 trace_seq_printf(s, "%9llu ", cpu_data->min_user / divisor); 280 trace_seq_printf(s, "%9llu ", 281 (cpu_data->sum_user / cpu_data->user_count) / divisor); 282 trace_seq_printf(s, "%9llu\n", cpu_data->max_user / divisor); 283 } 284 } 285 286 /* 287 * clear_terminal - clears the output terminal 288 */ 289 static void clear_terminal(struct trace_seq *seq) 290 { 291 if (!config_debug) 292 trace_seq_printf(seq, "\033c"); 293 } 294 295 /* 296 * timerlat_print_stats - print data for all cpus 297 */ 298 static void 299 timerlat_print_stats(struct timerlat_top_params *params, struct osnoise_tool *top) 300 { 301 struct trace_instance *trace = &top->trace; 302 static int nr_cpus = -1; 303 int i; 304 305 if (params->aa_only) 306 return; 307 308 if (nr_cpus == -1) 309 nr_cpus = sysconf(_SC_NPROCESSORS_CONF); 310 311 if (!params->quiet) 312 clear_terminal(trace->seq); 313 314 timerlat_top_header(top); 315 316 for (i = 0; i < nr_cpus; i++) { 317 if (params->cpus && !CPU_ISSET(i, ¶ms->monitored_cpus)) 318 continue; 319 timerlat_top_print(top, i); 320 } 321 322 trace_seq_do_printf(trace->seq); 323 trace_seq_reset(trace->seq); 324 } 325 326 /* 327 * timerlat_top_usage - prints timerlat top usage message 328 */ 329 static void timerlat_top_usage(char *usage) 330 { 331 int i; 332 333 static const char *const msg[] = { 334 "", 335 " usage: rtla timerlat [top] [-h] [-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\", 336 " [[-t[=file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\", 337 " [-P priority] [--dma-latency us] [--aa-only us] [-C[=cgroup_name]] [-u]", 338 "", 339 " -h/--help: print this menu", 340 " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit", 341 " --aa-only us: stop if <us> latency is hit, only printing the auto analysis (reduces CPU usage)", 342 " -p/--period us: timerlat period in us", 343 " -i/--irq us: stop trace if the irq latency is higher than the argument in us", 344 " -T/--thread us: stop trace if the thread latency is higher than the argument in us", 345 " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us", 346 " -c/--cpus cpus: run the tracer only on the given cpus", 347 " -H/--house-keeping cpus: run rtla control threads only on the given cpus", 348 " -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited", 349 " -d/--duration time[m|h|d]: duration of the session in seconds", 350 " -D/--debug: print debug info", 351 " --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)", 352 " -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]", 353 " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed", 354 " --filter <command>: enable a trace event filter to the previous -e event", 355 " --trigger <command>: enable a trace event trigger to the previous -e event", 356 " -n/--nano: display data in nanoseconds", 357 " --no-aa: disable auto-analysis, reducing rtla timerlat cpu usage", 358 " -q/--quiet print only a summary at the end", 359 " --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency", 360 " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters", 361 " o:prio - use SCHED_OTHER with prio", 362 " r:prio - use SCHED_RR with prio", 363 " f:prio - use SCHED_FIFO with prio", 364 " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period", 365 " in nanoseconds", 366 " -u/--user-threads: use rtla user-space threads instead of in-kernel timerlat threads", 367 NULL, 368 }; 369 370 if (usage) 371 fprintf(stderr, "%s\n", usage); 372 373 fprintf(stderr, "rtla timerlat top: a per-cpu summary of the timer latency (version %s)\n", 374 VERSION); 375 376 for (i = 0; msg[i]; i++) 377 fprintf(stderr, "%s\n", msg[i]); 378 exit(1); 379 } 380 381 /* 382 * timerlat_top_parse_args - allocs, parse and fill the cmd line parameters 383 */ 384 static struct timerlat_top_params 385 *timerlat_top_parse_args(int argc, char **argv) 386 { 387 struct timerlat_top_params *params; 388 struct trace_events *tevent; 389 long long auto_thresh; 390 int retval; 391 int c; 392 393 params = calloc(1, sizeof(*params)); 394 if (!params) 395 exit(1); 396 397 /* disabled by default */ 398 params->dma_latency = -1; 399 400 /* display data in microseconds */ 401 params->output_divisor = 1000; 402 403 while (1) { 404 static struct option long_options[] = { 405 {"auto", required_argument, 0, 'a'}, 406 {"cpus", required_argument, 0, 'c'}, 407 {"cgroup", optional_argument, 0, 'C'}, 408 {"debug", no_argument, 0, 'D'}, 409 {"duration", required_argument, 0, 'd'}, 410 {"event", required_argument, 0, 'e'}, 411 {"help", no_argument, 0, 'h'}, 412 {"house-keeping", required_argument, 0, 'H'}, 413 {"irq", required_argument, 0, 'i'}, 414 {"nano", no_argument, 0, 'n'}, 415 {"period", required_argument, 0, 'p'}, 416 {"priority", required_argument, 0, 'P'}, 417 {"quiet", no_argument, 0, 'q'}, 418 {"stack", required_argument, 0, 's'}, 419 {"thread", required_argument, 0, 'T'}, 420 {"trace", optional_argument, 0, 't'}, 421 {"user-threads", no_argument, 0, 'u'}, 422 {"trigger", required_argument, 0, '0'}, 423 {"filter", required_argument, 0, '1'}, 424 {"dma-latency", required_argument, 0, '2'}, 425 {"no-aa", no_argument, 0, '3'}, 426 {"dump-tasks", no_argument, 0, '4'}, 427 {"aa-only", required_argument, 0, '5'}, 428 {0, 0, 0, 0} 429 }; 430 431 /* getopt_long stores the option index here. */ 432 int option_index = 0; 433 434 c = getopt_long(argc, argv, "a:c:C::d:De:hH:i:np:P:qs:t::T:u0:1:2:345:", 435 long_options, &option_index); 436 437 /* detect the end of the options. */ 438 if (c == -1) 439 break; 440 441 switch (c) { 442 case 'a': 443 auto_thresh = get_llong_from_str(optarg); 444 445 /* set thread stop to auto_thresh */ 446 params->stop_total_us = auto_thresh; 447 params->stop_us = auto_thresh; 448 449 /* get stack trace */ 450 params->print_stack = auto_thresh; 451 452 /* set trace */ 453 params->trace_output = "timerlat_trace.txt"; 454 break; 455 case '5': 456 /* it is here because it is similar to -a */ 457 auto_thresh = get_llong_from_str(optarg); 458 459 /* set thread stop to auto_thresh */ 460 params->stop_total_us = auto_thresh; 461 params->stop_us = auto_thresh; 462 463 /* get stack trace */ 464 params->print_stack = auto_thresh; 465 466 /* set aa_only to avoid parsing the trace */ 467 params->aa_only = 1; 468 break; 469 case 'c': 470 retval = parse_cpu_set(optarg, ¶ms->monitored_cpus); 471 if (retval) 472 timerlat_top_usage("\nInvalid -c cpu list\n"); 473 params->cpus = optarg; 474 break; 475 case 'C': 476 params->cgroup = 1; 477 if (!optarg) { 478 /* will inherit this cgroup */ 479 params->cgroup_name = NULL; 480 } else if (*optarg == '=') { 481 /* skip the = */ 482 params->cgroup_name = ++optarg; 483 } 484 break; 485 case 'D': 486 config_debug = 1; 487 break; 488 case 'd': 489 params->duration = parse_seconds_duration(optarg); 490 if (!params->duration) 491 timerlat_top_usage("Invalid -D duration\n"); 492 break; 493 case 'e': 494 tevent = trace_event_alloc(optarg); 495 if (!tevent) { 496 err_msg("Error alloc trace event"); 497 exit(EXIT_FAILURE); 498 } 499 500 if (params->events) 501 tevent->next = params->events; 502 params->events = tevent; 503 break; 504 case 'h': 505 case '?': 506 timerlat_top_usage(NULL); 507 break; 508 case 'H': 509 params->hk_cpus = 1; 510 retval = parse_cpu_set(optarg, ¶ms->hk_cpu_set); 511 if (retval) { 512 err_msg("Error parsing house keeping CPUs\n"); 513 exit(EXIT_FAILURE); 514 } 515 break; 516 case 'i': 517 params->stop_us = get_llong_from_str(optarg); 518 break; 519 case 'n': 520 params->output_divisor = 1; 521 break; 522 case 'p': 523 params->timerlat_period_us = get_llong_from_str(optarg); 524 if (params->timerlat_period_us > 1000000) 525 timerlat_top_usage("Period longer than 1 s\n"); 526 break; 527 case 'P': 528 retval = parse_prio(optarg, ¶ms->sched_param); 529 if (retval == -1) 530 timerlat_top_usage("Invalid -P priority"); 531 params->set_sched = 1; 532 break; 533 case 'q': 534 params->quiet = 1; 535 break; 536 case 's': 537 params->print_stack = get_llong_from_str(optarg); 538 break; 539 case 'T': 540 params->stop_total_us = get_llong_from_str(optarg); 541 break; 542 case 't': 543 if (optarg) 544 /* skip = */ 545 params->trace_output = &optarg[1]; 546 else 547 params->trace_output = "timerlat_trace.txt"; 548 549 break; 550 case 'u': 551 params->user_top = true; 552 break; 553 case '0': /* trigger */ 554 if (params->events) { 555 retval = trace_event_add_trigger(params->events, optarg); 556 if (retval) { 557 err_msg("Error adding trigger %s\n", optarg); 558 exit(EXIT_FAILURE); 559 } 560 } else { 561 timerlat_top_usage("--trigger requires a previous -e\n"); 562 } 563 break; 564 case '1': /* filter */ 565 if (params->events) { 566 retval = trace_event_add_filter(params->events, optarg); 567 if (retval) { 568 err_msg("Error adding filter %s\n", optarg); 569 exit(EXIT_FAILURE); 570 } 571 } else { 572 timerlat_top_usage("--filter requires a previous -e\n"); 573 } 574 break; 575 case '2': /* dma-latency */ 576 params->dma_latency = get_llong_from_str(optarg); 577 if (params->dma_latency < 0 || params->dma_latency > 10000) { 578 err_msg("--dma-latency needs to be >= 0 and < 10000"); 579 exit(EXIT_FAILURE); 580 } 581 break; 582 case '3': /* no-aa */ 583 params->no_aa = 1; 584 break; 585 case '4': 586 params->dump_tasks = 1; 587 break; 588 default: 589 timerlat_top_usage("Invalid option"); 590 } 591 } 592 593 if (geteuid()) { 594 err_msg("rtla needs root permission\n"); 595 exit(EXIT_FAILURE); 596 } 597 598 /* 599 * Auto analysis only happens if stop tracing, thus: 600 */ 601 if (!params->stop_us && !params->stop_total_us) 602 params->no_aa = 1; 603 604 if (params->no_aa && params->aa_only) 605 timerlat_top_usage("--no-aa and --aa-only are mutually exclusive!"); 606 607 return params; 608 } 609 610 /* 611 * timerlat_top_apply_config - apply the top configs to the initialized tool 612 */ 613 static int 614 timerlat_top_apply_config(struct osnoise_tool *top, struct timerlat_top_params *params) 615 { 616 int retval; 617 int i; 618 619 if (!params->sleep_time) 620 params->sleep_time = 1; 621 622 if (params->cpus) { 623 retval = osnoise_set_cpus(top->context, params->cpus); 624 if (retval) { 625 err_msg("Failed to apply CPUs config\n"); 626 goto out_err; 627 } 628 } else { 629 for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++) 630 CPU_SET(i, ¶ms->monitored_cpus); 631 } 632 633 if (params->stop_us) { 634 retval = osnoise_set_stop_us(top->context, params->stop_us); 635 if (retval) { 636 err_msg("Failed to set stop us\n"); 637 goto out_err; 638 } 639 } 640 641 if (params->stop_total_us) { 642 retval = osnoise_set_stop_total_us(top->context, params->stop_total_us); 643 if (retval) { 644 err_msg("Failed to set stop total us\n"); 645 goto out_err; 646 } 647 } 648 649 650 if (params->timerlat_period_us) { 651 retval = osnoise_set_timerlat_period_us(top->context, params->timerlat_period_us); 652 if (retval) { 653 err_msg("Failed to set timerlat period\n"); 654 goto out_err; 655 } 656 } 657 658 659 if (params->print_stack) { 660 retval = osnoise_set_print_stack(top->context, params->print_stack); 661 if (retval) { 662 err_msg("Failed to set print stack\n"); 663 goto out_err; 664 } 665 } 666 667 if (params->hk_cpus) { 668 retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set), 669 ¶ms->hk_cpu_set); 670 if (retval == -1) { 671 err_msg("Failed to set rtla to the house keeping CPUs\n"); 672 goto out_err; 673 } 674 } else if (params->cpus) { 675 /* 676 * Even if the user do not set a house-keeping CPU, try to 677 * move rtla to a CPU set different to the one where the user 678 * set the workload to run. 679 * 680 * No need to check results as this is an automatic attempt. 681 */ 682 auto_house_keeping(¶ms->monitored_cpus); 683 } 684 685 if (params->user_top) { 686 retval = osnoise_set_workload(top->context, 0); 687 if (retval) { 688 err_msg("Failed to set OSNOISE_WORKLOAD option\n"); 689 goto out_err; 690 } 691 } 692 693 return 0; 694 695 out_err: 696 return -1; 697 } 698 699 /* 700 * timerlat_init_top - initialize a timerlat top tool with parameters 701 */ 702 static struct osnoise_tool 703 *timerlat_init_top(struct timerlat_top_params *params) 704 { 705 struct osnoise_tool *top; 706 int nr_cpus; 707 708 nr_cpus = sysconf(_SC_NPROCESSORS_CONF); 709 710 top = osnoise_init_tool("timerlat_top"); 711 if (!top) 712 return NULL; 713 714 top->data = timerlat_alloc_top(nr_cpus); 715 if (!top->data) 716 goto out_err; 717 718 top->params = params; 719 720 tep_register_event_handler(top->trace.tep, -1, "ftrace", "timerlat", 721 timerlat_top_handler, top); 722 723 return top; 724 725 out_err: 726 osnoise_destroy_tool(top); 727 return NULL; 728 } 729 730 static int stop_tracing; 731 static void stop_top(int sig) 732 { 733 stop_tracing = 1; 734 } 735 736 /* 737 * timerlat_top_set_signals - handles the signal to stop the tool 738 */ 739 static void 740 timerlat_top_set_signals(struct timerlat_top_params *params) 741 { 742 signal(SIGINT, stop_top); 743 if (params->duration) { 744 signal(SIGALRM, stop_top); 745 alarm(params->duration); 746 } 747 } 748 749 int timerlat_top_main(int argc, char *argv[]) 750 { 751 struct timerlat_top_params *params; 752 struct osnoise_tool *record = NULL; 753 struct timerlat_u_params params_u; 754 struct osnoise_tool *top = NULL; 755 struct osnoise_tool *aa = NULL; 756 struct trace_instance *trace; 757 int dma_latency_fd = -1; 758 pthread_t timerlat_u; 759 int return_value = 1; 760 char *max_lat; 761 int retval; 762 763 params = timerlat_top_parse_args(argc, argv); 764 if (!params) 765 exit(1); 766 767 top = timerlat_init_top(params); 768 if (!top) { 769 err_msg("Could not init osnoise top\n"); 770 goto out_exit; 771 } 772 773 retval = timerlat_top_apply_config(top, params); 774 if (retval) { 775 err_msg("Could not apply config\n"); 776 goto out_free; 777 } 778 779 trace = &top->trace; 780 781 retval = enable_timerlat(trace); 782 if (retval) { 783 err_msg("Failed to enable timerlat tracer\n"); 784 goto out_free; 785 } 786 787 if (params->set_sched) { 788 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param); 789 if (retval) { 790 err_msg("Failed to set sched parameters\n"); 791 goto out_free; 792 } 793 } 794 795 if (params->cgroup && !params->user_top) { 796 retval = set_comm_cgroup("timerlat/", params->cgroup_name); 797 if (!retval) { 798 err_msg("Failed to move threads to cgroup\n"); 799 goto out_free; 800 } 801 } 802 803 if (params->dma_latency >= 0) { 804 dma_latency_fd = set_cpu_dma_latency(params->dma_latency); 805 if (dma_latency_fd < 0) { 806 err_msg("Could not set /dev/cpu_dma_latency.\n"); 807 goto out_free; 808 } 809 } 810 811 if (params->trace_output) { 812 record = osnoise_init_trace_tool("timerlat"); 813 if (!record) { 814 err_msg("Failed to enable the trace instance\n"); 815 goto out_free; 816 } 817 818 if (params->events) { 819 retval = trace_events_enable(&record->trace, params->events); 820 if (retval) 821 goto out_top; 822 } 823 } 824 825 if (!params->no_aa) { 826 if (params->aa_only) { 827 /* as top is not used for display, use it for aa */ 828 aa = top; 829 } else { 830 /* otherwise, a new instance is needed */ 831 aa = osnoise_init_tool("timerlat_aa"); 832 if (!aa) 833 goto out_top; 834 } 835 836 retval = timerlat_aa_init(aa, params->dump_tasks); 837 if (retval) { 838 err_msg("Failed to enable the auto analysis instance\n"); 839 goto out_top; 840 } 841 842 /* if it is re-using the main instance, there is no need to start it */ 843 if (aa != top) { 844 retval = enable_timerlat(&aa->trace); 845 if (retval) { 846 err_msg("Failed to enable timerlat tracer\n"); 847 goto out_top; 848 } 849 } 850 } 851 852 /* 853 * Start the tracers here, after having set all instances. 854 * 855 * Let the trace instance start first for the case of hitting a stop 856 * tracing while enabling other instances. The trace instance is the 857 * one with most valuable information. 858 */ 859 if (params->trace_output) 860 trace_instance_start(&record->trace); 861 if (!params->no_aa && aa != top) 862 trace_instance_start(&aa->trace); 863 trace_instance_start(trace); 864 865 top->start_time = time(NULL); 866 timerlat_top_set_signals(params); 867 868 if (params->user_top) { 869 /* rtla asked to stop */ 870 params_u.should_run = 1; 871 /* all threads left */ 872 params_u.stopped_running = 0; 873 874 params_u.set = ¶ms->monitored_cpus; 875 if (params->set_sched) 876 params_u.sched_param = ¶ms->sched_param; 877 else 878 params_u.sched_param = NULL; 879 880 params_u.cgroup_name = params->cgroup_name; 881 882 retval = pthread_create(&timerlat_u, NULL, timerlat_u_dispatcher, ¶ms_u); 883 if (retval) 884 err_msg("Error creating timerlat user-space threads\n"); 885 } 886 887 while (!stop_tracing) { 888 sleep(params->sleep_time); 889 890 if (params->aa_only && !trace_is_off(&top->trace, &record->trace)) 891 continue; 892 893 retval = tracefs_iterate_raw_events(trace->tep, 894 trace->inst, 895 NULL, 896 0, 897 collect_registered_events, 898 trace); 899 if (retval < 0) { 900 err_msg("Error iterating on events\n"); 901 goto out_top; 902 } 903 904 if (!params->quiet) 905 timerlat_print_stats(params, top); 906 907 if (trace_is_off(&top->trace, &record->trace)) 908 break; 909 910 /* is there still any user-threads ? */ 911 if (params->user_top) { 912 if (params_u.stopped_running) { 913 debug_msg("timerlat user space threads stopped!\n"); 914 break; 915 } 916 } 917 } 918 919 if (params->user_top && !params_u.stopped_running) { 920 params_u.should_run = 0; 921 sleep(1); 922 } 923 924 timerlat_print_stats(params, top); 925 926 return_value = 0; 927 928 if (trace_is_off(&top->trace, &record->trace)) { 929 printf("rtla timerlat hit stop tracing\n"); 930 931 if (!params->no_aa) 932 timerlat_auto_analysis(params->stop_us, params->stop_total_us); 933 934 if (params->trace_output) { 935 printf(" Saving trace to %s\n", params->trace_output); 936 save_trace_to_file(record->trace.inst, params->trace_output); 937 } 938 } else if (params->aa_only) { 939 /* 940 * If the trace did not stop with --aa-only, at least print the 941 * max known latency. 942 */ 943 max_lat = tracefs_instance_file_read(trace->inst, "tracing_max_latency", NULL); 944 if (max_lat) { 945 printf(" Max latency was %s\n", max_lat); 946 free(max_lat); 947 } 948 } 949 950 out_top: 951 timerlat_aa_destroy(); 952 if (dma_latency_fd >= 0) 953 close(dma_latency_fd); 954 trace_events_destroy(&record->trace, params->events); 955 params->events = NULL; 956 out_free: 957 timerlat_free_top(top->data); 958 if (aa && aa != top) 959 osnoise_destroy_tool(aa); 960 osnoise_destroy_tool(record); 961 osnoise_destroy_tool(top); 962 free(params); 963 out_exit: 964 exit(return_value); 965 } 966