1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira <bristot@kernel.org>
4 */
5
6 #include <getopt.h>
7 #include <stdlib.h>
8 #include <string.h>
9 #include <signal.h>
10 #include <unistd.h>
11 #include <stdio.h>
12 #include <time.h>
13
14 #include "utils.h"
15 #include "osnoise.h"
16 #include "timerlat.h"
17
18 struct timerlat_hist_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 set_sched;
31 int dma_latency;
32 struct sched_attr sched_param;
33 struct trace_events *events;
34
35 char no_irq;
36 char no_thread;
37 char no_header;
38 char no_summary;
39 char no_index;
40 char with_zeros;
41 int bucket_size;
42 int entries;
43 };
44
45 struct timerlat_hist_cpu {
46 int *irq;
47 int *thread;
48
49 int irq_count;
50 int thread_count;
51
52 unsigned long long min_irq;
53 unsigned long long sum_irq;
54 unsigned long long max_irq;
55
56 unsigned long long min_thread;
57 unsigned long long sum_thread;
58 unsigned long long max_thread;
59 };
60
61 struct timerlat_hist_data {
62 struct timerlat_hist_cpu *hist;
63 int entries;
64 int bucket_size;
65 int nr_cpus;
66 };
67
68 /*
69 * timerlat_free_histogram - free runtime data
70 */
71 static void
timerlat_free_histogram(struct timerlat_hist_data * data)72 timerlat_free_histogram(struct timerlat_hist_data *data)
73 {
74 int cpu;
75
76 /* one histogram for IRQ and one for thread, per CPU */
77 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
78 if (data->hist[cpu].irq)
79 free(data->hist[cpu].irq);
80
81 if (data->hist[cpu].thread)
82 free(data->hist[cpu].thread);
83 }
84
85 /* one set of histograms per CPU */
86 if (data->hist)
87 free(data->hist);
88
89 free(data);
90 }
91
92 /*
93 * timerlat_alloc_histogram - alloc runtime data
94 */
95 static struct timerlat_hist_data
timerlat_alloc_histogram(int nr_cpus,int entries,int bucket_size)96 *timerlat_alloc_histogram(int nr_cpus, int entries, int bucket_size)
97 {
98 struct timerlat_hist_data *data;
99 int cpu;
100
101 data = calloc(1, sizeof(*data));
102 if (!data)
103 return NULL;
104
105 data->entries = entries;
106 data->bucket_size = bucket_size;
107 data->nr_cpus = nr_cpus;
108
109 /* one set of histograms per CPU */
110 data->hist = calloc(1, sizeof(*data->hist) * nr_cpus);
111 if (!data->hist)
112 goto cleanup;
113
114 /* one histogram for IRQ and one for thread, per cpu */
115 for (cpu = 0; cpu < nr_cpus; cpu++) {
116 data->hist[cpu].irq = calloc(1, sizeof(*data->hist->irq) * (entries + 1));
117 if (!data->hist[cpu].irq)
118 goto cleanup;
119 data->hist[cpu].thread = calloc(1, sizeof(*data->hist->thread) * (entries + 1));
120 if (!data->hist[cpu].thread)
121 goto cleanup;
122 }
123
124 /* set the min to max */
125 for (cpu = 0; cpu < nr_cpus; cpu++) {
126 data->hist[cpu].min_irq = ~0;
127 data->hist[cpu].min_thread = ~0;
128 }
129
130 return data;
131
132 cleanup:
133 timerlat_free_histogram(data);
134 return NULL;
135 }
136
137 /*
138 * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
139 */
140 static void
timerlat_hist_update(struct osnoise_tool * tool,int cpu,unsigned long long thread,unsigned long long latency)141 timerlat_hist_update(struct osnoise_tool *tool, int cpu,
142 unsigned long long thread,
143 unsigned long long latency)
144 {
145 struct timerlat_hist_params *params = tool->params;
146 struct timerlat_hist_data *data = tool->data;
147 int entries = data->entries;
148 int bucket;
149 int *hist;
150
151 if (params->output_divisor)
152 latency = latency / params->output_divisor;
153
154 bucket = latency / data->bucket_size;
155
156 if (!thread) {
157 hist = data->hist[cpu].irq;
158 data->hist[cpu].irq_count++;
159 update_min(&data->hist[cpu].min_irq, &latency);
160 update_sum(&data->hist[cpu].sum_irq, &latency);
161 update_max(&data->hist[cpu].max_irq, &latency);
162 } else {
163 hist = data->hist[cpu].thread;
164 data->hist[cpu].thread_count++;
165 update_min(&data->hist[cpu].min_thread, &latency);
166 update_sum(&data->hist[cpu].sum_thread, &latency);
167 update_max(&data->hist[cpu].max_thread, &latency);
168 }
169
170 if (bucket < entries)
171 hist[bucket]++;
172 else
173 hist[entries]++;
174 }
175
176 /*
177 * timerlat_hist_handler - this is the handler for timerlat tracer events
178 */
179 static int
timerlat_hist_handler(struct trace_seq * s,struct tep_record * record,struct tep_event * event,void * data)180 timerlat_hist_handler(struct trace_seq *s, struct tep_record *record,
181 struct tep_event *event, void *data)
182 {
183 struct trace_instance *trace = data;
184 unsigned long long thread, latency;
185 struct osnoise_tool *tool;
186 int cpu = record->cpu;
187
188 tool = container_of(trace, struct osnoise_tool, trace);
189
190 tep_get_field_val(s, event, "context", record, &thread, 1);
191 tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
192
193 timerlat_hist_update(tool, cpu, thread, latency);
194
195 return 0;
196 }
197
198 /*
199 * timerlat_hist_header - print the header of the tracer to the output
200 */
timerlat_hist_header(struct osnoise_tool * tool)201 static void timerlat_hist_header(struct osnoise_tool *tool)
202 {
203 struct timerlat_hist_params *params = tool->params;
204 struct timerlat_hist_data *data = tool->data;
205 struct trace_seq *s = tool->trace.seq;
206 char duration[26];
207 int cpu;
208
209 if (params->no_header)
210 return;
211
212 get_duration(tool->start_time, duration, sizeof(duration));
213 trace_seq_printf(s, "# RTLA timerlat histogram\n");
214 trace_seq_printf(s, "# Time unit is %s (%s)\n",
215 params->output_divisor == 1 ? "nanoseconds" : "microseconds",
216 params->output_divisor == 1 ? "ns" : "us");
217
218 trace_seq_printf(s, "# Duration: %s\n", duration);
219
220 if (!params->no_index)
221 trace_seq_printf(s, "Index");
222
223 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
224 if (params->cpus && !params->monitored_cpus[cpu])
225 continue;
226
227 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
228 continue;
229
230 if (!params->no_irq)
231 trace_seq_printf(s, " IRQ-%03d", cpu);
232
233 if (!params->no_thread)
234 trace_seq_printf(s, " Thr-%03d", cpu);
235 }
236 trace_seq_printf(s, "\n");
237
238
239 trace_seq_do_printf(s);
240 trace_seq_reset(s);
241 }
242
243 /*
244 * timerlat_print_summary - print the summary of the hist data to the output
245 */
246 static void
timerlat_print_summary(struct timerlat_hist_params * params,struct trace_instance * trace,struct timerlat_hist_data * data)247 timerlat_print_summary(struct timerlat_hist_params *params,
248 struct trace_instance *trace,
249 struct timerlat_hist_data *data)
250 {
251 int cpu;
252
253 if (params->no_summary)
254 return;
255
256 if (!params->no_index)
257 trace_seq_printf(trace->seq, "count:");
258
259 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
260 if (params->cpus && !params->monitored_cpus[cpu])
261 continue;
262
263 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
264 continue;
265
266 if (!params->no_irq)
267 trace_seq_printf(trace->seq, "%9d ",
268 data->hist[cpu].irq_count);
269
270 if (!params->no_thread)
271 trace_seq_printf(trace->seq, "%9d ",
272 data->hist[cpu].thread_count);
273 }
274 trace_seq_printf(trace->seq, "\n");
275
276 if (!params->no_index)
277 trace_seq_printf(trace->seq, "min: ");
278
279 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
280 if (params->cpus && !params->monitored_cpus[cpu])
281 continue;
282
283 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
284 continue;
285
286 if (!params->no_irq)
287 trace_seq_printf(trace->seq, "%9llu ",
288 data->hist[cpu].min_irq);
289
290 if (!params->no_thread)
291 trace_seq_printf(trace->seq, "%9llu ",
292 data->hist[cpu].min_thread);
293 }
294 trace_seq_printf(trace->seq, "\n");
295
296 if (!params->no_index)
297 trace_seq_printf(trace->seq, "avg: ");
298
299 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
300 if (params->cpus && !params->monitored_cpus[cpu])
301 continue;
302
303 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
304 continue;
305
306 if (!params->no_irq) {
307 if (data->hist[cpu].irq_count)
308 trace_seq_printf(trace->seq, "%9llu ",
309 data->hist[cpu].sum_irq / data->hist[cpu].irq_count);
310 else
311 trace_seq_printf(trace->seq, " - ");
312 }
313
314 if (!params->no_thread) {
315 if (data->hist[cpu].thread_count)
316 trace_seq_printf(trace->seq, "%9llu ",
317 data->hist[cpu].sum_thread / data->hist[cpu].thread_count);
318 else
319 trace_seq_printf(trace->seq, " - ");
320 }
321 }
322 trace_seq_printf(trace->seq, "\n");
323
324 if (!params->no_index)
325 trace_seq_printf(trace->seq, "max: ");
326
327 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
328 if (params->cpus && !params->monitored_cpus[cpu])
329 continue;
330
331 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
332 continue;
333
334 if (!params->no_irq)
335 trace_seq_printf(trace->seq, "%9llu ",
336 data->hist[cpu].max_irq);
337
338 if (!params->no_thread)
339 trace_seq_printf(trace->seq, "%9llu ",
340 data->hist[cpu].max_thread);
341 }
342 trace_seq_printf(trace->seq, "\n");
343 trace_seq_do_printf(trace->seq);
344 trace_seq_reset(trace->seq);
345 }
346
347 /*
348 * timerlat_print_stats - print data for all CPUs
349 */
350 static void
timerlat_print_stats(struct timerlat_hist_params * params,struct osnoise_tool * tool)351 timerlat_print_stats(struct timerlat_hist_params *params, struct osnoise_tool *tool)
352 {
353 struct timerlat_hist_data *data = tool->data;
354 struct trace_instance *trace = &tool->trace;
355 int bucket, cpu;
356 int total;
357
358 timerlat_hist_header(tool);
359
360 for (bucket = 0; bucket < data->entries; bucket++) {
361 total = 0;
362
363 if (!params->no_index)
364 trace_seq_printf(trace->seq, "%-6d",
365 bucket * data->bucket_size);
366
367 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
368 if (params->cpus && !params->monitored_cpus[cpu])
369 continue;
370
371 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
372 continue;
373
374 if (!params->no_irq) {
375 total += data->hist[cpu].irq[bucket];
376 trace_seq_printf(trace->seq, "%9d ",
377 data->hist[cpu].irq[bucket]);
378 }
379
380 if (!params->no_thread) {
381 total += data->hist[cpu].thread[bucket];
382 trace_seq_printf(trace->seq, "%9d ",
383 data->hist[cpu].thread[bucket]);
384 }
385
386 }
387
388 if (total == 0 && !params->with_zeros) {
389 trace_seq_reset(trace->seq);
390 continue;
391 }
392
393 trace_seq_printf(trace->seq, "\n");
394 trace_seq_do_printf(trace->seq);
395 trace_seq_reset(trace->seq);
396 }
397
398 if (!params->no_index)
399 trace_seq_printf(trace->seq, "over: ");
400
401 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
402 if (params->cpus && !params->monitored_cpus[cpu])
403 continue;
404
405 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
406 continue;
407
408 if (!params->no_irq)
409 trace_seq_printf(trace->seq, "%9d ",
410 data->hist[cpu].irq[data->entries]);
411
412 if (!params->no_thread)
413 trace_seq_printf(trace->seq, "%9d ",
414 data->hist[cpu].thread[data->entries]);
415 }
416 trace_seq_printf(trace->seq, "\n");
417 trace_seq_do_printf(trace->seq);
418 trace_seq_reset(trace->seq);
419
420 timerlat_print_summary(params, trace, data);
421 }
422
423 /*
424 * timerlat_hist_usage - prints timerlat top usage message
425 */
timerlat_hist_usage(char * usage)426 static void timerlat_hist_usage(char *usage)
427 {
428 int i;
429
430 char *msg[] = {
431 "",
432 " usage: [rtla] timerlat hist [-h] [-q] [-d s] [-D] [-n] [-a us] [-p us] [-i us] [-T us] [-s us] \\",
433 " [-t[=file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] \\",
434 " [-P priority] [-E N] [-b N] [--no-irq] [--no-thread] [--no-header] [--no-summary] \\",
435 " [--no-index] [--with-zeros] [--dma-latency us]",
436 "",
437 " -h/--help: print this menu",
438 " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
439 " -p/--period us: timerlat period in us",
440 " -i/--irq us: stop trace if the irq latency is higher than the argument in us",
441 " -T/--thread us: stop trace if the thread latency is higher than the argument in us",
442 " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
443 " -c/--cpus cpus: run the tracer only on the given cpus",
444 " -d/--duration time[m|h|d]: duration of the session in seconds",
445 " -D/--debug: print debug info",
446 " -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]",
447 " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
448 " --filter <filter>: enable a trace event filter to the previous -e event",
449 " --trigger <trigger>: enable a trace event trigger to the previous -e event",
450 " -n/--nano: display data in nanoseconds",
451 " -b/--bucket-size N: set the histogram bucket size (default 1)",
452 " -E/--entries N: set the number of entries of the histogram (default 256)",
453 " --no-irq: ignore IRQ latencies",
454 " --no-thread: ignore thread latencies",
455 " --no-header: do not print header",
456 " --no-summary: do not print summary",
457 " --no-index: do not print index",
458 " --with-zeros: print zero only entries",
459 " --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency",
460 " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
461 " o:prio - use SCHED_OTHER with prio",
462 " r:prio - use SCHED_RR with prio",
463 " f:prio - use SCHED_FIFO with prio",
464 " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period",
465 " in nanoseconds",
466 NULL,
467 };
468
469 if (usage)
470 fprintf(stderr, "%s\n", usage);
471
472 fprintf(stderr, "rtla timerlat hist: a per-cpu histogram of the timer latency (version %s)\n",
473 VERSION);
474
475 for (i = 0; msg[i]; i++)
476 fprintf(stderr, "%s\n", msg[i]);
477
478 if (usage)
479 exit(EXIT_FAILURE);
480
481 exit(EXIT_SUCCESS);
482 }
483
484 /*
485 * timerlat_hist_parse_args - allocs, parse and fill the cmd line parameters
486 */
487 static struct timerlat_hist_params
timerlat_hist_parse_args(int argc,char * argv[])488 *timerlat_hist_parse_args(int argc, char *argv[])
489 {
490 struct timerlat_hist_params *params;
491 struct trace_events *tevent;
492 int auto_thresh;
493 int retval;
494 int c;
495
496 params = calloc(1, sizeof(*params));
497 if (!params)
498 exit(1);
499
500 /* disabled by default */
501 params->dma_latency = -1;
502
503 /* display data in microseconds */
504 params->output_divisor = 1000;
505 params->bucket_size = 1;
506 params->entries = 256;
507
508 while (1) {
509 static struct option long_options[] = {
510 {"auto", required_argument, 0, 'a'},
511 {"cpus", required_argument, 0, 'c'},
512 {"bucket-size", required_argument, 0, 'b'},
513 {"debug", no_argument, 0, 'D'},
514 {"entries", required_argument, 0, 'E'},
515 {"duration", required_argument, 0, 'd'},
516 {"help", no_argument, 0, 'h'},
517 {"irq", required_argument, 0, 'i'},
518 {"nano", no_argument, 0, 'n'},
519 {"period", required_argument, 0, 'p'},
520 {"priority", required_argument, 0, 'P'},
521 {"stack", required_argument, 0, 's'},
522 {"thread", required_argument, 0, 'T'},
523 {"trace", optional_argument, 0, 't'},
524 {"event", required_argument, 0, 'e'},
525 {"no-irq", no_argument, 0, '0'},
526 {"no-thread", no_argument, 0, '1'},
527 {"no-header", no_argument, 0, '2'},
528 {"no-summary", no_argument, 0, '3'},
529 {"no-index", no_argument, 0, '4'},
530 {"with-zeros", no_argument, 0, '5'},
531 {"trigger", required_argument, 0, '6'},
532 {"filter", required_argument, 0, '7'},
533 {"dma-latency", required_argument, 0, '8'},
534 {0, 0, 0, 0}
535 };
536
537 /* getopt_long stores the option index here. */
538 int option_index = 0;
539
540 c = getopt_long(argc, argv, "a:c:b:d:e:E:Dhi:np:P:s:t::T:0123456:7:8:",
541 long_options, &option_index);
542
543 /* detect the end of the options. */
544 if (c == -1)
545 break;
546
547 switch (c) {
548 case 'a':
549 auto_thresh = get_llong_from_str(optarg);
550
551 /* set thread stop to auto_thresh */
552 params->stop_total_us = auto_thresh;
553
554 /* get stack trace */
555 params->print_stack = auto_thresh;
556
557 /* set trace */
558 params->trace_output = "timerlat_trace.txt";
559
560 break;
561 case 'c':
562 retval = parse_cpu_list(optarg, ¶ms->monitored_cpus);
563 if (retval)
564 timerlat_hist_usage("\nInvalid -c cpu list\n");
565 params->cpus = optarg;
566 break;
567 case 'b':
568 params->bucket_size = get_llong_from_str(optarg);
569 if ((params->bucket_size == 0) || (params->bucket_size >= 1000000))
570 timerlat_hist_usage("Bucket size needs to be > 0 and <= 1000000\n");
571 break;
572 case 'D':
573 config_debug = 1;
574 break;
575 case 'd':
576 params->duration = parse_seconds_duration(optarg);
577 if (!params->duration)
578 timerlat_hist_usage("Invalid -D duration\n");
579 break;
580 case 'e':
581 tevent = trace_event_alloc(optarg);
582 if (!tevent) {
583 err_msg("Error alloc trace event");
584 exit(EXIT_FAILURE);
585 }
586
587 if (params->events)
588 tevent->next = params->events;
589
590 params->events = tevent;
591 break;
592 case 'E':
593 params->entries = get_llong_from_str(optarg);
594 if ((params->entries < 10) || (params->entries > 9999999))
595 timerlat_hist_usage("Entries must be > 10 and < 9999999\n");
596 break;
597 case 'h':
598 case '?':
599 timerlat_hist_usage(NULL);
600 break;
601 case 'i':
602 params->stop_us = get_llong_from_str(optarg);
603 break;
604 case 'n':
605 params->output_divisor = 1;
606 break;
607 case 'p':
608 params->timerlat_period_us = get_llong_from_str(optarg);
609 if (params->timerlat_period_us > 1000000)
610 timerlat_hist_usage("Period longer than 1 s\n");
611 break;
612 case 'P':
613 retval = parse_prio(optarg, ¶ms->sched_param);
614 if (retval == -1)
615 timerlat_hist_usage("Invalid -P priority");
616 params->set_sched = 1;
617 break;
618 case 's':
619 params->print_stack = get_llong_from_str(optarg);
620 break;
621 case 'T':
622 params->stop_total_us = get_llong_from_str(optarg);
623 break;
624 case 't':
625 if (optarg)
626 /* skip = */
627 params->trace_output = &optarg[1];
628 else
629 params->trace_output = "timerlat_trace.txt";
630 break;
631 case '0': /* no irq */
632 params->no_irq = 1;
633 break;
634 case '1': /* no thread */
635 params->no_thread = 1;
636 break;
637 case '2': /* no header */
638 params->no_header = 1;
639 break;
640 case '3': /* no summary */
641 params->no_summary = 1;
642 break;
643 case '4': /* no index */
644 params->no_index = 1;
645 break;
646 case '5': /* with zeros */
647 params->with_zeros = 1;
648 break;
649 case '6': /* trigger */
650 if (params->events) {
651 retval = trace_event_add_trigger(params->events, optarg);
652 if (retval) {
653 err_msg("Error adding trigger %s\n", optarg);
654 exit(EXIT_FAILURE);
655 }
656 } else {
657 timerlat_hist_usage("--trigger requires a previous -e\n");
658 }
659 break;
660 case '7': /* filter */
661 if (params->events) {
662 retval = trace_event_add_filter(params->events, optarg);
663 if (retval) {
664 err_msg("Error adding filter %s\n", optarg);
665 exit(EXIT_FAILURE);
666 }
667 } else {
668 timerlat_hist_usage("--filter requires a previous -e\n");
669 }
670 break;
671 case '8':
672 params->dma_latency = get_llong_from_str(optarg);
673 if (params->dma_latency < 0 || params->dma_latency > 10000) {
674 err_msg("--dma-latency needs to be >= 0 and < 10000");
675 exit(EXIT_FAILURE);
676 }
677 break;
678 default:
679 timerlat_hist_usage("Invalid option");
680 }
681 }
682
683 if (geteuid()) {
684 err_msg("rtla needs root permission\n");
685 exit(EXIT_FAILURE);
686 }
687
688 if (params->no_irq && params->no_thread)
689 timerlat_hist_usage("no-irq and no-thread set, there is nothing to do here");
690
691 if (params->no_index && !params->with_zeros)
692 timerlat_hist_usage("no-index set with with-zeros is not set - it does not make sense");
693
694 return params;
695 }
696
697 /*
698 * timerlat_hist_apply_config - apply the hist configs to the initialized tool
699 */
700 static int
timerlat_hist_apply_config(struct osnoise_tool * tool,struct timerlat_hist_params * params)701 timerlat_hist_apply_config(struct osnoise_tool *tool, struct timerlat_hist_params *params)
702 {
703 int retval;
704
705 if (!params->sleep_time)
706 params->sleep_time = 1;
707
708 if (params->cpus) {
709 retval = osnoise_set_cpus(tool->context, params->cpus);
710 if (retval) {
711 err_msg("Failed to apply CPUs config\n");
712 goto out_err;
713 }
714 }
715
716 if (params->stop_us) {
717 retval = osnoise_set_stop_us(tool->context, params->stop_us);
718 if (retval) {
719 err_msg("Failed to set stop us\n");
720 goto out_err;
721 }
722 }
723
724 if (params->stop_total_us) {
725 retval = osnoise_set_stop_total_us(tool->context, params->stop_total_us);
726 if (retval) {
727 err_msg("Failed to set stop total us\n");
728 goto out_err;
729 }
730 }
731
732 if (params->timerlat_period_us) {
733 retval = osnoise_set_timerlat_period_us(tool->context, params->timerlat_period_us);
734 if (retval) {
735 err_msg("Failed to set timerlat period\n");
736 goto out_err;
737 }
738 }
739
740 if (params->print_stack) {
741 retval = osnoise_set_print_stack(tool->context, params->print_stack);
742 if (retval) {
743 err_msg("Failed to set print stack\n");
744 goto out_err;
745 }
746 }
747
748 return 0;
749
750 out_err:
751 return -1;
752 }
753
754 /*
755 * timerlat_init_hist - initialize a timerlat hist tool with parameters
756 */
757 static struct osnoise_tool
timerlat_init_hist(struct timerlat_hist_params * params)758 *timerlat_init_hist(struct timerlat_hist_params *params)
759 {
760 struct osnoise_tool *tool;
761 int nr_cpus;
762
763 nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
764
765 tool = osnoise_init_tool("timerlat_hist");
766 if (!tool)
767 return NULL;
768
769 tool->data = timerlat_alloc_histogram(nr_cpus, params->entries, params->bucket_size);
770 if (!tool->data)
771 goto out_err;
772
773 tool->params = params;
774
775 tep_register_event_handler(tool->trace.tep, -1, "ftrace", "timerlat",
776 timerlat_hist_handler, tool);
777
778 return tool;
779
780 out_err:
781 osnoise_destroy_tool(tool);
782 return NULL;
783 }
784
785 static int stop_tracing;
stop_hist(int sig)786 static void stop_hist(int sig)
787 {
788 stop_tracing = 1;
789 }
790
791 /*
792 * timerlat_hist_set_signals - handles the signal to stop the tool
793 */
794 static void
timerlat_hist_set_signals(struct timerlat_hist_params * params)795 timerlat_hist_set_signals(struct timerlat_hist_params *params)
796 {
797 signal(SIGINT, stop_hist);
798 if (params->duration) {
799 signal(SIGALRM, stop_hist);
800 alarm(params->duration);
801 }
802 }
803
timerlat_hist_main(int argc,char * argv[])804 int timerlat_hist_main(int argc, char *argv[])
805 {
806 struct timerlat_hist_params *params;
807 struct osnoise_tool *record = NULL;
808 struct osnoise_tool *tool = NULL;
809 struct trace_instance *trace;
810 int dma_latency_fd = -1;
811 int return_value = 1;
812 int retval;
813
814 params = timerlat_hist_parse_args(argc, argv);
815 if (!params)
816 exit(1);
817
818 tool = timerlat_init_hist(params);
819 if (!tool) {
820 err_msg("Could not init osnoise hist\n");
821 goto out_exit;
822 }
823
824 retval = timerlat_hist_apply_config(tool, params);
825 if (retval) {
826 err_msg("Could not apply config\n");
827 goto out_free;
828 }
829
830 trace = &tool->trace;
831
832 retval = enable_timerlat(trace);
833 if (retval) {
834 err_msg("Failed to enable timerlat tracer\n");
835 goto out_free;
836 }
837
838 if (params->set_sched) {
839 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param);
840 if (retval) {
841 err_msg("Failed to set sched parameters\n");
842 goto out_free;
843 }
844 }
845
846 if (params->dma_latency >= 0) {
847 dma_latency_fd = set_cpu_dma_latency(params->dma_latency);
848 if (dma_latency_fd < 0) {
849 err_msg("Could not set /dev/cpu_dma_latency.\n");
850 goto out_free;
851 }
852 }
853
854 trace_instance_start(trace);
855
856 if (params->trace_output) {
857 record = osnoise_init_trace_tool("timerlat");
858 if (!record) {
859 err_msg("Failed to enable the trace instance\n");
860 goto out_free;
861 }
862
863 if (params->events) {
864 retval = trace_events_enable(&record->trace, params->events);
865 if (retval)
866 goto out_hist;
867 }
868
869 trace_instance_start(&record->trace);
870 }
871
872 tool->start_time = time(NULL);
873 timerlat_hist_set_signals(params);
874
875 while (!stop_tracing) {
876 sleep(params->sleep_time);
877
878 retval = tracefs_iterate_raw_events(trace->tep,
879 trace->inst,
880 NULL,
881 0,
882 collect_registered_events,
883 trace);
884 if (retval < 0) {
885 err_msg("Error iterating on events\n");
886 goto out_hist;
887 }
888
889 if (trace_is_off(&tool->trace, &record->trace))
890 break;
891 }
892
893 timerlat_print_stats(params, tool);
894
895 return_value = 0;
896
897 if (trace_is_off(&tool->trace, &record->trace)) {
898 printf("rtla timerlat hit stop tracing\n");
899 if (params->trace_output) {
900 printf(" Saving trace to %s\n", params->trace_output);
901 save_trace_to_file(record->trace.inst, params->trace_output);
902 }
903 }
904
905 out_hist:
906 if (dma_latency_fd >= 0)
907 close(dma_latency_fd);
908 trace_events_destroy(&record->trace, params->events);
909 params->events = NULL;
910 out_free:
911 timerlat_free_histogram(tool->data);
912 osnoise_destroy_tool(record);
913 osnoise_destroy_tool(tool);
914 free(params);
915 out_exit:
916 exit(return_value);
917 }
918