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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
18struct 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 int dma_latency;
33 struct sched_attr sched_param;
34 struct trace_events *events;
35};
36
37struct timerlat_top_cpu {
38 int irq_count;
39 int thread_count;
40
41 unsigned long long cur_irq;
42 unsigned long long min_irq;
43 unsigned long long sum_irq;
44 unsigned long long max_irq;
45
46 unsigned long long cur_thread;
47 unsigned long long min_thread;
48 unsigned long long sum_thread;
49 unsigned long long max_thread;
50};
51
52struct timerlat_top_data {
53 struct timerlat_top_cpu *cpu_data;
54 int nr_cpus;
55};
56
57/*
58 * timerlat_free_top - free runtime data
59 */
60static void
61timerlat_free_top(struct timerlat_top_data *data)
62{
63 free(data->cpu_data);
64 free(data);
65}
66
67/*
68 * timerlat_alloc_histogram - alloc runtime data
69 */
70static struct timerlat_top_data *timerlat_alloc_top(int nr_cpus)
71{
72 struct timerlat_top_data *data;
73 int cpu;
74
75 data = calloc(1, sizeof(*data));
76 if (!data)
77 return NULL;
78
79 data->nr_cpus = nr_cpus;
80
81 /* one set of histograms per CPU */
82 data->cpu_data = calloc(1, sizeof(*data->cpu_data) * nr_cpus);
83 if (!data->cpu_data)
84 goto cleanup;
85
86 /* set the min to max */
87 for (cpu = 0; cpu < nr_cpus; cpu++) {
88 data->cpu_data[cpu].min_irq = ~0;
89 data->cpu_data[cpu].min_thread = ~0;
90 }
91
92 return data;
93
94cleanup:
95 timerlat_free_top(data);
96 return NULL;
97}
98
99/*
100 * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
101 */
102static void
103timerlat_top_update(struct osnoise_tool *tool, int cpu,
104 unsigned long long thread,
105 unsigned long long latency)
106{
107 struct timerlat_top_data *data = tool->data;
108 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
109
110 if (!thread) {
111 cpu_data->irq_count++;
112 cpu_data->cur_irq = latency;
113 update_min(&cpu_data->min_irq, &latency);
114 update_sum(&cpu_data->sum_irq, &latency);
115 update_max(&cpu_data->max_irq, &latency);
116 } else {
117 cpu_data->thread_count++;
118 cpu_data->cur_thread = latency;
119 update_min(&cpu_data->min_thread, &latency);
120 update_sum(&cpu_data->sum_thread, &latency);
121 update_max(&cpu_data->max_thread, &latency);
122 }
123}
124
125/*
126 * timerlat_top_handler - this is the handler for timerlat tracer events
127 */
128static int
129timerlat_top_handler(struct trace_seq *s, struct tep_record *record,
130 struct tep_event *event, void *context)
131{
132 struct trace_instance *trace = context;
133 unsigned long long latency, thread;
134 struct osnoise_tool *top;
135 int cpu = record->cpu;
136
137 top = container_of(trace, struct osnoise_tool, trace);
138
139 tep_get_field_val(s, event, "context", record, &thread, 1);
140 tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
141
142 timerlat_top_update(top, cpu, thread, latency);
143
144 return 0;
145}
146
147/*
148 * timerlat_top_header - print the header of the tool output
149 */
150static void timerlat_top_header(struct osnoise_tool *top)
151{
152 struct timerlat_top_params *params = top->params;
153 struct trace_seq *s = top->trace.seq;
154 char duration[26];
155
156 get_duration(top->start_time, duration, sizeof(duration));
157
158 trace_seq_printf(s, "\033[2;37;40m");
159 trace_seq_printf(s, " Timer Latency ");
160 trace_seq_printf(s, "\033[0;0;0m");
161 trace_seq_printf(s, "\n");
162
163 trace_seq_printf(s, "%-6s | IRQ Timer Latency (%s) | Thread Timer Latency (%s)\n", duration,
164 params->output_divisor == 1 ? "ns" : "us",
165 params->output_divisor == 1 ? "ns" : "us");
166
167 trace_seq_printf(s, "\033[2;30;47m");
168 trace_seq_printf(s, "CPU COUNT | cur min avg max | cur min avg max");
169 trace_seq_printf(s, "\033[0;0;0m");
170 trace_seq_printf(s, "\n");
171}
172
173/*
174 * timerlat_top_print - prints the output of a given CPU
175 */
176static void timerlat_top_print(struct osnoise_tool *top, int cpu)
177{
178
179 struct timerlat_top_params *params = top->params;
180 struct timerlat_top_data *data = top->data;
181 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
182 int divisor = params->output_divisor;
183 struct trace_seq *s = top->trace.seq;
184
185 if (divisor == 0)
186 return;
187
188 /*
189 * Skip if no data is available: is this cpu offline?
190 */
191 if (!cpu_data->irq_count && !cpu_data->thread_count)
192 return;
193
194 /*
195 * Unless trace is being lost, IRQ counter is always the max.
196 */
197 trace_seq_printf(s, "%3d #%-9d |", cpu, cpu_data->irq_count);
198
199 if (!cpu_data->irq_count) {
200 trace_seq_printf(s, " - ");
201 trace_seq_printf(s, " - ");
202 trace_seq_printf(s, " - ");
203 trace_seq_printf(s, " - |");
204 } else {
205 trace_seq_printf(s, "%9llu ", cpu_data->cur_irq / params->output_divisor);
206 trace_seq_printf(s, "%9llu ", cpu_data->min_irq / params->output_divisor);
207 trace_seq_printf(s, "%9llu ", (cpu_data->sum_irq / cpu_data->irq_count) / divisor);
208 trace_seq_printf(s, "%9llu |", cpu_data->max_irq / divisor);
209 }
210
211 if (!cpu_data->thread_count) {
212 trace_seq_printf(s, " - ");
213 trace_seq_printf(s, " - ");
214 trace_seq_printf(s, " - ");
215 trace_seq_printf(s, " -\n");
216 } else {
217 trace_seq_printf(s, "%9llu ", cpu_data->cur_thread / divisor);
218 trace_seq_printf(s, "%9llu ", cpu_data->min_thread / divisor);
219 trace_seq_printf(s, "%9llu ",
220 (cpu_data->sum_thread / cpu_data->thread_count) / divisor);
221 trace_seq_printf(s, "%9llu\n", cpu_data->max_thread / divisor);
222 }
223}
224
225/*
226 * clear_terminal - clears the output terminal
227 */
228static void clear_terminal(struct trace_seq *seq)
229{
230 if (!config_debug)
231 trace_seq_printf(seq, "\033c");
232}
233
234/*
235 * timerlat_print_stats - print data for all cpus
236 */
237static void
238timerlat_print_stats(struct timerlat_top_params *params, struct osnoise_tool *top)
239{
240 struct trace_instance *trace = &top->trace;
241 static int nr_cpus = -1;
242 int i;
243
244 if (nr_cpus == -1)
245 nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
246
247 if (!params->quiet)
248 clear_terminal(trace->seq);
249
250 timerlat_top_header(top);
251
252 for (i = 0; i < nr_cpus; i++) {
253 if (params->cpus && !params->monitored_cpus[i])
254 continue;
255 timerlat_top_print(top, i);
256 }
257
258 trace_seq_do_printf(trace->seq);
259 trace_seq_reset(trace->seq);
260}
261
262/*
263 * timerlat_top_usage - prints timerlat top usage message
264 */
265static void timerlat_top_usage(char *usage)
266{
267 int i;
268
269 static const char *const msg[] = {
270 "",
271 " usage: rtla timerlat [top] [-h] [-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\",
272 " [[-t[=file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] \\",
273 " [-P priority] [--dma-latency us]",
274 "",
275 " -h/--help: print this menu",
276 " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
277 " -p/--period us: timerlat period in us",
278 " -i/--irq us: stop trace if the irq latency is higher than the argument in us",
279 " -T/--thread us: stop trace if the thread latency is higher than the argument in us",
280 " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
281 " -c/--cpus cpus: run the tracer only on the given cpus",
282 " -d/--duration time[m|h|d]: duration of the session in seconds",
283 " -D/--debug: print debug info",
284 " -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]",
285 " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
286 " --filter <command>: enable a trace event filter to the previous -e event",
287 " --trigger <command>: enable a trace event trigger to the previous -e event",
288 " -n/--nano: display data in nanoseconds",
289 " -q/--quiet print only a summary at the end",
290 " --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency",
291 " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
292 " o:prio - use SCHED_OTHER with prio",
293 " r:prio - use SCHED_RR with prio",
294 " f:prio - use SCHED_FIFO with prio",
295 " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period",
296 " in nanoseconds",
297 NULL,
298 };
299
300 if (usage)
301 fprintf(stderr, "%s\n", usage);
302
303 fprintf(stderr, "rtla timerlat top: a per-cpu summary of the timer latency (version %s)\n",
304 VERSION);
305
306 for (i = 0; msg[i]; i++)
307 fprintf(stderr, "%s\n", msg[i]);
308 exit(1);
309}
310
311/*
312 * timerlat_top_parse_args - allocs, parse and fill the cmd line parameters
313 */
314static struct timerlat_top_params
315*timerlat_top_parse_args(int argc, char **argv)
316{
317 struct timerlat_top_params *params;
318 struct trace_events *tevent;
319 long long auto_thresh;
320 int retval;
321 int c;
322
323 params = calloc(1, sizeof(*params));
324 if (!params)
325 exit(1);
326
327 /* disabled by default */
328 params->dma_latency = -1;
329
330 /* display data in microseconds */
331 params->output_divisor = 1000;
332
333 while (1) {
334 static struct option long_options[] = {
335 {"auto", required_argument, 0, 'a'},
336 {"cpus", required_argument, 0, 'c'},
337 {"debug", no_argument, 0, 'D'},
338 {"duration", required_argument, 0, 'd'},
339 {"event", required_argument, 0, 'e'},
340 {"help", no_argument, 0, 'h'},
341 {"irq", required_argument, 0, 'i'},
342 {"nano", no_argument, 0, 'n'},
343 {"period", required_argument, 0, 'p'},
344 {"priority", required_argument, 0, 'P'},
345 {"quiet", no_argument, 0, 'q'},
346 {"stack", required_argument, 0, 's'},
347 {"thread", required_argument, 0, 'T'},
348 {"trace", optional_argument, 0, 't'},
349 {"trigger", required_argument, 0, '0'},
350 {"filter", required_argument, 0, '1'},
351 {"dma-latency", required_argument, 0, '2'},
352 {0, 0, 0, 0}
353 };
354
355 /* getopt_long stores the option index here. */
356 int option_index = 0;
357
358 c = getopt_long(argc, argv, "a:c:d:De:hi:np:P:qs:t::T:0:1:2:",
359 long_options, &option_index);
360
361 /* detect the end of the options. */
362 if (c == -1)
363 break;
364
365 switch (c) {
366 case 'a':
367 auto_thresh = get_llong_from_str(optarg);
368
369 /* set thread stop to auto_thresh */
370 params->stop_total_us = auto_thresh;
371
372 /* get stack trace */
373 params->print_stack = auto_thresh;
374
375 /* set trace */
376 params->trace_output = "timerlat_trace.txt";
377
378 break;
379 case 'c':
380 retval = parse_cpu_list(optarg, ¶ms->monitored_cpus);
381 if (retval)
382 timerlat_top_usage("\nInvalid -c cpu list\n");
383 params->cpus = optarg;
384 break;
385 case 'D':
386 config_debug = 1;
387 break;
388 case 'd':
389 params->duration = parse_seconds_duration(optarg);
390 if (!params->duration)
391 timerlat_top_usage("Invalid -D duration\n");
392 break;
393 case 'e':
394 tevent = trace_event_alloc(optarg);
395 if (!tevent) {
396 err_msg("Error alloc trace event");
397 exit(EXIT_FAILURE);
398 }
399
400 if (params->events)
401 tevent->next = params->events;
402 params->events = tevent;
403 break;
404 case 'h':
405 case '?':
406 timerlat_top_usage(NULL);
407 break;
408 case 'i':
409 params->stop_us = get_llong_from_str(optarg);
410 break;
411 case 'n':
412 params->output_divisor = 1;
413 break;
414 case 'p':
415 params->timerlat_period_us = get_llong_from_str(optarg);
416 if (params->timerlat_period_us > 1000000)
417 timerlat_top_usage("Period longer than 1 s\n");
418 break;
419 case 'P':
420 retval = parse_prio(optarg, ¶ms->sched_param);
421 if (retval == -1)
422 timerlat_top_usage("Invalid -P priority");
423 params->set_sched = 1;
424 break;
425 case 'q':
426 params->quiet = 1;
427 break;
428 case 's':
429 params->print_stack = get_llong_from_str(optarg);
430 break;
431 case 'T':
432 params->stop_total_us = get_llong_from_str(optarg);
433 break;
434 case 't':
435 if (optarg)
436 /* skip = */
437 params->trace_output = &optarg[1];
438 else
439 params->trace_output = "timerlat_trace.txt";
440 break;
441 case '0': /* trigger */
442 if (params->events) {
443 retval = trace_event_add_trigger(params->events, optarg);
444 if (retval) {
445 err_msg("Error adding trigger %s\n", optarg);
446 exit(EXIT_FAILURE);
447 }
448 } else {
449 timerlat_top_usage("--trigger requires a previous -e\n");
450 }
451 break;
452 case '1': /* filter */
453 if (params->events) {
454 retval = trace_event_add_filter(params->events, optarg);
455 if (retval) {
456 err_msg("Error adding filter %s\n", optarg);
457 exit(EXIT_FAILURE);
458 }
459 } else {
460 timerlat_top_usage("--filter requires a previous -e\n");
461 }
462 break;
463 case '2': /* dma-latency */
464 params->dma_latency = get_llong_from_str(optarg);
465 if (params->dma_latency < 0 || params->dma_latency > 10000) {
466 err_msg("--dma-latency needs to be >= 0 and < 10000");
467 exit(EXIT_FAILURE);
468 }
469 break;
470 default:
471 timerlat_top_usage("Invalid option");
472 }
473 }
474
475 if (geteuid()) {
476 err_msg("rtla needs root permission\n");
477 exit(EXIT_FAILURE);
478 }
479
480 return params;
481}
482
483/*
484 * timerlat_top_apply_config - apply the top configs to the initialized tool
485 */
486static int
487timerlat_top_apply_config(struct osnoise_tool *top, struct timerlat_top_params *params)
488{
489 int retval;
490
491 if (!params->sleep_time)
492 params->sleep_time = 1;
493
494 if (params->cpus) {
495 retval = osnoise_set_cpus(top->context, params->cpus);
496 if (retval) {
497 err_msg("Failed to apply CPUs config\n");
498 goto out_err;
499 }
500 }
501
502 if (params->stop_us) {
503 retval = osnoise_set_stop_us(top->context, params->stop_us);
504 if (retval) {
505 err_msg("Failed to set stop us\n");
506 goto out_err;
507 }
508 }
509
510 if (params->stop_total_us) {
511 retval = osnoise_set_stop_total_us(top->context, params->stop_total_us);
512 if (retval) {
513 err_msg("Failed to set stop total us\n");
514 goto out_err;
515 }
516 }
517
518
519 if (params->timerlat_period_us) {
520 retval = osnoise_set_timerlat_period_us(top->context, params->timerlat_period_us);
521 if (retval) {
522 err_msg("Failed to set timerlat period\n");
523 goto out_err;
524 }
525 }
526
527
528 if (params->print_stack) {
529 retval = osnoise_set_print_stack(top->context, params->print_stack);
530 if (retval) {
531 err_msg("Failed to set print stack\n");
532 goto out_err;
533 }
534 }
535
536 return 0;
537
538out_err:
539 return -1;
540}
541
542/*
543 * timerlat_init_top - initialize a timerlat top tool with parameters
544 */
545static struct osnoise_tool
546*timerlat_init_top(struct timerlat_top_params *params)
547{
548 struct osnoise_tool *top;
549 int nr_cpus;
550
551 nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
552
553 top = osnoise_init_tool("timerlat_top");
554 if (!top)
555 return NULL;
556
557 top->data = timerlat_alloc_top(nr_cpus);
558 if (!top->data)
559 goto out_err;
560
561 top->params = params;
562
563 tep_register_event_handler(top->trace.tep, -1, "ftrace", "timerlat",
564 timerlat_top_handler, top);
565
566 return top;
567
568out_err:
569 osnoise_destroy_tool(top);
570 return NULL;
571}
572
573static int stop_tracing;
574static void stop_top(int sig)
575{
576 stop_tracing = 1;
577}
578
579/*
580 * timerlat_top_set_signals - handles the signal to stop the tool
581 */
582static void
583timerlat_top_set_signals(struct timerlat_top_params *params)
584{
585 signal(SIGINT, stop_top);
586 if (params->duration) {
587 signal(SIGALRM, stop_top);
588 alarm(params->duration);
589 }
590}
591
592int timerlat_top_main(int argc, char *argv[])
593{
594 struct timerlat_top_params *params;
595 struct osnoise_tool *record = NULL;
596 struct osnoise_tool *top = NULL;
597 struct trace_instance *trace;
598 int dma_latency_fd = -1;
599 int return_value = 1;
600 int retval;
601
602 params = timerlat_top_parse_args(argc, argv);
603 if (!params)
604 exit(1);
605
606 top = timerlat_init_top(params);
607 if (!top) {
608 err_msg("Could not init osnoise top\n");
609 goto out_exit;
610 }
611
612 retval = timerlat_top_apply_config(top, params);
613 if (retval) {
614 err_msg("Could not apply config\n");
615 goto out_free;
616 }
617
618 trace = &top->trace;
619
620 retval = enable_timerlat(trace);
621 if (retval) {
622 err_msg("Failed to enable timerlat tracer\n");
623 goto out_free;
624 }
625
626 if (params->set_sched) {
627 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param);
628 if (retval) {
629 err_msg("Failed to set sched parameters\n");
630 goto out_free;
631 }
632 }
633
634 if (params->dma_latency >= 0) {
635 dma_latency_fd = set_cpu_dma_latency(params->dma_latency);
636 if (dma_latency_fd < 0) {
637 err_msg("Could not set /dev/cpu_dma_latency.\n");
638 goto out_free;
639 }
640 }
641
642 trace_instance_start(trace);
643
644 if (params->trace_output) {
645 record = osnoise_init_trace_tool("timerlat");
646 if (!record) {
647 err_msg("Failed to enable the trace instance\n");
648 goto out_free;
649 }
650
651 if (params->events) {
652 retval = trace_events_enable(&record->trace, params->events);
653 if (retval)
654 goto out_top;
655 }
656
657 trace_instance_start(&record->trace);
658 }
659
660 top->start_time = time(NULL);
661 timerlat_top_set_signals(params);
662
663 while (!stop_tracing) {
664 sleep(params->sleep_time);
665
666 retval = tracefs_iterate_raw_events(trace->tep,
667 trace->inst,
668 NULL,
669 0,
670 collect_registered_events,
671 trace);
672 if (retval < 0) {
673 err_msg("Error iterating on events\n");
674 goto out_top;
675 }
676
677 if (!params->quiet)
678 timerlat_print_stats(params, top);
679
680 if (trace_is_off(&top->trace, &record->trace))
681 break;
682
683 }
684
685 timerlat_print_stats(params, top);
686
687 return_value = 0;
688
689 if (trace_is_off(&top->trace, &record->trace)) {
690 printf("rtla timerlat hit stop tracing\n");
691 if (params->trace_output) {
692 printf(" Saving trace to %s\n", params->trace_output);
693 save_trace_to_file(record->trace.inst, params->trace_output);
694 }
695 }
696
697out_top:
698 if (dma_latency_fd >= 0)
699 close(dma_latency_fd);
700 trace_events_destroy(&record->trace, params->events);
701 params->events = NULL;
702out_free:
703 timerlat_free_top(top->data);
704 osnoise_destroy_tool(record);
705 osnoise_destroy_tool(top);
706 free(params);
707out_exit:
708 exit(return_value);
709}
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
24struct 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
51struct 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
72struct 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 */
80static void
81timerlat_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 */
90static 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
115cleanup:
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 */
123static void
124timerlat_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 */
155static int
156timerlat_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 */
181static 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 */
217static 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 */
289static 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 */
298static void
299timerlat_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 */
329static 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
379 if (usage)
380 exit(EXIT_FAILURE);
381
382 exit(EXIT_SUCCESS);
383}
384
385/*
386 * timerlat_top_parse_args - allocs, parse and fill the cmd line parameters
387 */
388static struct timerlat_top_params
389*timerlat_top_parse_args(int argc, char **argv)
390{
391 struct timerlat_top_params *params;
392 struct trace_events *tevent;
393 long long auto_thresh;
394 int retval;
395 int c;
396
397 params = calloc(1, sizeof(*params));
398 if (!params)
399 exit(1);
400
401 /* disabled by default */
402 params->dma_latency = -1;
403
404 /* display data in microseconds */
405 params->output_divisor = 1000;
406
407 while (1) {
408 static struct option long_options[] = {
409 {"auto", required_argument, 0, 'a'},
410 {"cpus", required_argument, 0, 'c'},
411 {"cgroup", optional_argument, 0, 'C'},
412 {"debug", no_argument, 0, 'D'},
413 {"duration", required_argument, 0, 'd'},
414 {"event", required_argument, 0, 'e'},
415 {"help", no_argument, 0, 'h'},
416 {"house-keeping", required_argument, 0, 'H'},
417 {"irq", required_argument, 0, 'i'},
418 {"nano", no_argument, 0, 'n'},
419 {"period", required_argument, 0, 'p'},
420 {"priority", required_argument, 0, 'P'},
421 {"quiet", no_argument, 0, 'q'},
422 {"stack", required_argument, 0, 's'},
423 {"thread", required_argument, 0, 'T'},
424 {"trace", optional_argument, 0, 't'},
425 {"user-threads", no_argument, 0, 'u'},
426 {"trigger", required_argument, 0, '0'},
427 {"filter", required_argument, 0, '1'},
428 {"dma-latency", required_argument, 0, '2'},
429 {"no-aa", no_argument, 0, '3'},
430 {"dump-tasks", no_argument, 0, '4'},
431 {"aa-only", required_argument, 0, '5'},
432 {0, 0, 0, 0}
433 };
434
435 /* getopt_long stores the option index here. */
436 int option_index = 0;
437
438 c = getopt_long(argc, argv, "a:c:C::d:De:hH:i:np:P:qs:t::T:u0:1:2:345:",
439 long_options, &option_index);
440
441 /* detect the end of the options. */
442 if (c == -1)
443 break;
444
445 switch (c) {
446 case 'a':
447 auto_thresh = get_llong_from_str(optarg);
448
449 /* set thread stop to auto_thresh */
450 params->stop_total_us = auto_thresh;
451 params->stop_us = auto_thresh;
452
453 /* get stack trace */
454 params->print_stack = auto_thresh;
455
456 /* set trace */
457 params->trace_output = "timerlat_trace.txt";
458 break;
459 case '5':
460 /* it is here because it is similar to -a */
461 auto_thresh = get_llong_from_str(optarg);
462
463 /* set thread stop to auto_thresh */
464 params->stop_total_us = auto_thresh;
465 params->stop_us = auto_thresh;
466
467 /* get stack trace */
468 params->print_stack = auto_thresh;
469
470 /* set aa_only to avoid parsing the trace */
471 params->aa_only = 1;
472 break;
473 case 'c':
474 retval = parse_cpu_set(optarg, ¶ms->monitored_cpus);
475 if (retval)
476 timerlat_top_usage("\nInvalid -c cpu list\n");
477 params->cpus = optarg;
478 break;
479 case 'C':
480 params->cgroup = 1;
481 if (!optarg) {
482 /* will inherit this cgroup */
483 params->cgroup_name = NULL;
484 } else if (*optarg == '=') {
485 /* skip the = */
486 params->cgroup_name = ++optarg;
487 }
488 break;
489 case 'D':
490 config_debug = 1;
491 break;
492 case 'd':
493 params->duration = parse_seconds_duration(optarg);
494 if (!params->duration)
495 timerlat_top_usage("Invalid -D duration\n");
496 break;
497 case 'e':
498 tevent = trace_event_alloc(optarg);
499 if (!tevent) {
500 err_msg("Error alloc trace event");
501 exit(EXIT_FAILURE);
502 }
503
504 if (params->events)
505 tevent->next = params->events;
506 params->events = tevent;
507 break;
508 case 'h':
509 case '?':
510 timerlat_top_usage(NULL);
511 break;
512 case 'H':
513 params->hk_cpus = 1;
514 retval = parse_cpu_set(optarg, ¶ms->hk_cpu_set);
515 if (retval) {
516 err_msg("Error parsing house keeping CPUs\n");
517 exit(EXIT_FAILURE);
518 }
519 break;
520 case 'i':
521 params->stop_us = get_llong_from_str(optarg);
522 break;
523 case 'n':
524 params->output_divisor = 1;
525 break;
526 case 'p':
527 params->timerlat_period_us = get_llong_from_str(optarg);
528 if (params->timerlat_period_us > 1000000)
529 timerlat_top_usage("Period longer than 1 s\n");
530 break;
531 case 'P':
532 retval = parse_prio(optarg, ¶ms->sched_param);
533 if (retval == -1)
534 timerlat_top_usage("Invalid -P priority");
535 params->set_sched = 1;
536 break;
537 case 'q':
538 params->quiet = 1;
539 break;
540 case 's':
541 params->print_stack = get_llong_from_str(optarg);
542 break;
543 case 'T':
544 params->stop_total_us = get_llong_from_str(optarg);
545 break;
546 case 't':
547 if (optarg)
548 /* skip = */
549 params->trace_output = &optarg[1];
550 else
551 params->trace_output = "timerlat_trace.txt";
552
553 break;
554 case 'u':
555 params->user_top = true;
556 break;
557 case '0': /* trigger */
558 if (params->events) {
559 retval = trace_event_add_trigger(params->events, optarg);
560 if (retval) {
561 err_msg("Error adding trigger %s\n", optarg);
562 exit(EXIT_FAILURE);
563 }
564 } else {
565 timerlat_top_usage("--trigger requires a previous -e\n");
566 }
567 break;
568 case '1': /* filter */
569 if (params->events) {
570 retval = trace_event_add_filter(params->events, optarg);
571 if (retval) {
572 err_msg("Error adding filter %s\n", optarg);
573 exit(EXIT_FAILURE);
574 }
575 } else {
576 timerlat_top_usage("--filter requires a previous -e\n");
577 }
578 break;
579 case '2': /* dma-latency */
580 params->dma_latency = get_llong_from_str(optarg);
581 if (params->dma_latency < 0 || params->dma_latency > 10000) {
582 err_msg("--dma-latency needs to be >= 0 and < 10000");
583 exit(EXIT_FAILURE);
584 }
585 break;
586 case '3': /* no-aa */
587 params->no_aa = 1;
588 break;
589 case '4':
590 params->dump_tasks = 1;
591 break;
592 default:
593 timerlat_top_usage("Invalid option");
594 }
595 }
596
597 if (geteuid()) {
598 err_msg("rtla needs root permission\n");
599 exit(EXIT_FAILURE);
600 }
601
602 /*
603 * Auto analysis only happens if stop tracing, thus:
604 */
605 if (!params->stop_us && !params->stop_total_us)
606 params->no_aa = 1;
607
608 if (params->no_aa && params->aa_only)
609 timerlat_top_usage("--no-aa and --aa-only are mutually exclusive!");
610
611 return params;
612}
613
614/*
615 * timerlat_top_apply_config - apply the top configs to the initialized tool
616 */
617static int
618timerlat_top_apply_config(struct osnoise_tool *top, struct timerlat_top_params *params)
619{
620 int retval;
621 int i;
622
623 if (!params->sleep_time)
624 params->sleep_time = 1;
625
626 if (params->cpus) {
627 retval = osnoise_set_cpus(top->context, params->cpus);
628 if (retval) {
629 err_msg("Failed to apply CPUs config\n");
630 goto out_err;
631 }
632 } else {
633 for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++)
634 CPU_SET(i, ¶ms->monitored_cpus);
635 }
636
637 if (params->stop_us) {
638 retval = osnoise_set_stop_us(top->context, params->stop_us);
639 if (retval) {
640 err_msg("Failed to set stop us\n");
641 goto out_err;
642 }
643 }
644
645 if (params->stop_total_us) {
646 retval = osnoise_set_stop_total_us(top->context, params->stop_total_us);
647 if (retval) {
648 err_msg("Failed to set stop total us\n");
649 goto out_err;
650 }
651 }
652
653
654 if (params->timerlat_period_us) {
655 retval = osnoise_set_timerlat_period_us(top->context, params->timerlat_period_us);
656 if (retval) {
657 err_msg("Failed to set timerlat period\n");
658 goto out_err;
659 }
660 }
661
662
663 if (params->print_stack) {
664 retval = osnoise_set_print_stack(top->context, params->print_stack);
665 if (retval) {
666 err_msg("Failed to set print stack\n");
667 goto out_err;
668 }
669 }
670
671 if (params->hk_cpus) {
672 retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set),
673 ¶ms->hk_cpu_set);
674 if (retval == -1) {
675 err_msg("Failed to set rtla to the house keeping CPUs\n");
676 goto out_err;
677 }
678 } else if (params->cpus) {
679 /*
680 * Even if the user do not set a house-keeping CPU, try to
681 * move rtla to a CPU set different to the one where the user
682 * set the workload to run.
683 *
684 * No need to check results as this is an automatic attempt.
685 */
686 auto_house_keeping(¶ms->monitored_cpus);
687 }
688
689 if (params->user_top) {
690 retval = osnoise_set_workload(top->context, 0);
691 if (retval) {
692 err_msg("Failed to set OSNOISE_WORKLOAD option\n");
693 goto out_err;
694 }
695 }
696
697 return 0;
698
699out_err:
700 return -1;
701}
702
703/*
704 * timerlat_init_top - initialize a timerlat top tool with parameters
705 */
706static struct osnoise_tool
707*timerlat_init_top(struct timerlat_top_params *params)
708{
709 struct osnoise_tool *top;
710 int nr_cpus;
711
712 nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
713
714 top = osnoise_init_tool("timerlat_top");
715 if (!top)
716 return NULL;
717
718 top->data = timerlat_alloc_top(nr_cpus);
719 if (!top->data)
720 goto out_err;
721
722 top->params = params;
723
724 tep_register_event_handler(top->trace.tep, -1, "ftrace", "timerlat",
725 timerlat_top_handler, top);
726
727 return top;
728
729out_err:
730 osnoise_destroy_tool(top);
731 return NULL;
732}
733
734static int stop_tracing;
735static void stop_top(int sig)
736{
737 stop_tracing = 1;
738}
739
740/*
741 * timerlat_top_set_signals - handles the signal to stop the tool
742 */
743static void
744timerlat_top_set_signals(struct timerlat_top_params *params)
745{
746 signal(SIGINT, stop_top);
747 if (params->duration) {
748 signal(SIGALRM, stop_top);
749 alarm(params->duration);
750 }
751}
752
753int timerlat_top_main(int argc, char *argv[])
754{
755 struct timerlat_top_params *params;
756 struct osnoise_tool *record = NULL;
757 struct timerlat_u_params params_u;
758 struct osnoise_tool *top = NULL;
759 struct osnoise_tool *aa = NULL;
760 struct trace_instance *trace;
761 int dma_latency_fd = -1;
762 pthread_t timerlat_u;
763 int return_value = 1;
764 char *max_lat;
765 int retval;
766
767 params = timerlat_top_parse_args(argc, argv);
768 if (!params)
769 exit(1);
770
771 top = timerlat_init_top(params);
772 if (!top) {
773 err_msg("Could not init osnoise top\n");
774 goto out_exit;
775 }
776
777 retval = timerlat_top_apply_config(top, params);
778 if (retval) {
779 err_msg("Could not apply config\n");
780 goto out_free;
781 }
782
783 trace = &top->trace;
784
785 retval = enable_timerlat(trace);
786 if (retval) {
787 err_msg("Failed to enable timerlat tracer\n");
788 goto out_free;
789 }
790
791 if (params->set_sched) {
792 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param);
793 if (retval) {
794 err_msg("Failed to set sched parameters\n");
795 goto out_free;
796 }
797 }
798
799 if (params->cgroup && !params->user_top) {
800 retval = set_comm_cgroup("timerlat/", params->cgroup_name);
801 if (!retval) {
802 err_msg("Failed to move threads to cgroup\n");
803 goto out_free;
804 }
805 }
806
807 if (params->dma_latency >= 0) {
808 dma_latency_fd = set_cpu_dma_latency(params->dma_latency);
809 if (dma_latency_fd < 0) {
810 err_msg("Could not set /dev/cpu_dma_latency.\n");
811 goto out_free;
812 }
813 }
814
815 if (params->trace_output) {
816 record = osnoise_init_trace_tool("timerlat");
817 if (!record) {
818 err_msg("Failed to enable the trace instance\n");
819 goto out_free;
820 }
821
822 if (params->events) {
823 retval = trace_events_enable(&record->trace, params->events);
824 if (retval)
825 goto out_top;
826 }
827 }
828
829 if (!params->no_aa) {
830 if (params->aa_only) {
831 /* as top is not used for display, use it for aa */
832 aa = top;
833 } else {
834 /* otherwise, a new instance is needed */
835 aa = osnoise_init_tool("timerlat_aa");
836 if (!aa)
837 goto out_top;
838 }
839
840 retval = timerlat_aa_init(aa, params->dump_tasks);
841 if (retval) {
842 err_msg("Failed to enable the auto analysis instance\n");
843 goto out_top;
844 }
845
846 /* if it is re-using the main instance, there is no need to start it */
847 if (aa != top) {
848 retval = enable_timerlat(&aa->trace);
849 if (retval) {
850 err_msg("Failed to enable timerlat tracer\n");
851 goto out_top;
852 }
853 }
854 }
855
856 /*
857 * Start the tracers here, after having set all instances.
858 *
859 * Let the trace instance start first for the case of hitting a stop
860 * tracing while enabling other instances. The trace instance is the
861 * one with most valuable information.
862 */
863 if (params->trace_output)
864 trace_instance_start(&record->trace);
865 if (!params->no_aa && aa != top)
866 trace_instance_start(&aa->trace);
867 trace_instance_start(trace);
868
869 top->start_time = time(NULL);
870 timerlat_top_set_signals(params);
871
872 if (params->user_top) {
873 /* rtla asked to stop */
874 params_u.should_run = 1;
875 /* all threads left */
876 params_u.stopped_running = 0;
877
878 params_u.set = ¶ms->monitored_cpus;
879 if (params->set_sched)
880 params_u.sched_param = ¶ms->sched_param;
881 else
882 params_u.sched_param = NULL;
883
884 params_u.cgroup_name = params->cgroup_name;
885
886 retval = pthread_create(&timerlat_u, NULL, timerlat_u_dispatcher, ¶ms_u);
887 if (retval)
888 err_msg("Error creating timerlat user-space threads\n");
889 }
890
891 while (!stop_tracing) {
892 sleep(params->sleep_time);
893
894 if (params->aa_only && !trace_is_off(&top->trace, &record->trace))
895 continue;
896
897 retval = tracefs_iterate_raw_events(trace->tep,
898 trace->inst,
899 NULL,
900 0,
901 collect_registered_events,
902 trace);
903 if (retval < 0) {
904 err_msg("Error iterating on events\n");
905 goto out_top;
906 }
907
908 if (!params->quiet)
909 timerlat_print_stats(params, top);
910
911 if (trace_is_off(&top->trace, &record->trace))
912 break;
913
914 /* is there still any user-threads ? */
915 if (params->user_top) {
916 if (params_u.stopped_running) {
917 debug_msg("timerlat user space threads stopped!\n");
918 break;
919 }
920 }
921 }
922
923 if (params->user_top && !params_u.stopped_running) {
924 params_u.should_run = 0;
925 sleep(1);
926 }
927
928 timerlat_print_stats(params, top);
929
930 return_value = 0;
931
932 if (trace_is_off(&top->trace, &record->trace)) {
933 printf("rtla timerlat hit stop tracing\n");
934
935 if (!params->no_aa)
936 timerlat_auto_analysis(params->stop_us, params->stop_total_us);
937
938 if (params->trace_output) {
939 printf(" Saving trace to %s\n", params->trace_output);
940 save_trace_to_file(record->trace.inst, params->trace_output);
941 }
942 } else if (params->aa_only) {
943 /*
944 * If the trace did not stop with --aa-only, at least print the
945 * max known latency.
946 */
947 max_lat = tracefs_instance_file_read(trace->inst, "tracing_max_latency", NULL);
948 if (max_lat) {
949 printf(" Max latency was %s\n", max_lat);
950 free(max_lat);
951 }
952 }
953
954out_top:
955 timerlat_aa_destroy();
956 if (dma_latency_fd >= 0)
957 close(dma_latency_fd);
958 trace_events_destroy(&record->trace, params->events);
959 params->events = NULL;
960out_free:
961 timerlat_free_top(top->data);
962 if (aa && aa != top)
963 osnoise_destroy_tool(aa);
964 osnoise_destroy_tool(record);
965 osnoise_destroy_tool(top);
966 free(params);
967out_exit:
968 exit(return_value);
969}