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Linux kernel mirror (for testing)
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linux
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 <sched.h>
15#include <pthread.h>
16
17#include "utils.h"
18#include "osnoise.h"
19#include "timerlat.h"
20#include "timerlat_aa.h"
21#include "timerlat_u.h"
22
23struct timerlat_hist_params {
24 char *cpus;
25 cpu_set_t monitored_cpus;
26 char *trace_output;
27 char *cgroup_name;
28 unsigned long long runtime;
29 long long stop_us;
30 long long stop_total_us;
31 long long timerlat_period_us;
32 long long print_stack;
33 int sleep_time;
34 int output_divisor;
35 int duration;
36 int set_sched;
37 int dma_latency;
38 int cgroup;
39 int hk_cpus;
40 int no_aa;
41 int dump_tasks;
42 int user_workload;
43 int user_hist;
44 cpu_set_t hk_cpu_set;
45 struct sched_attr sched_param;
46 struct trace_events *events;
47 char no_irq;
48 char no_thread;
49 char no_header;
50 char no_summary;
51 char no_index;
52 char with_zeros;
53 int bucket_size;
54 int entries;
55};
56
57struct timerlat_hist_cpu {
58 int *irq;
59 int *thread;
60 int *user;
61
62 int irq_count;
63 int thread_count;
64 int user_count;
65
66 unsigned long long min_irq;
67 unsigned long long sum_irq;
68 unsigned long long max_irq;
69
70 unsigned long long min_thread;
71 unsigned long long sum_thread;
72 unsigned long long max_thread;
73
74 unsigned long long min_user;
75 unsigned long long sum_user;
76 unsigned long long max_user;
77};
78
79struct timerlat_hist_data {
80 struct timerlat_hist_cpu *hist;
81 int entries;
82 int bucket_size;
83 int nr_cpus;
84};
85
86/*
87 * timerlat_free_histogram - free runtime data
88 */
89static void
90timerlat_free_histogram(struct timerlat_hist_data *data)
91{
92 int cpu;
93
94 /* one histogram for IRQ and one for thread, per CPU */
95 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
96 if (data->hist[cpu].irq)
97 free(data->hist[cpu].irq);
98
99 if (data->hist[cpu].thread)
100 free(data->hist[cpu].thread);
101
102 if (data->hist[cpu].user)
103 free(data->hist[cpu].user);
104
105 }
106
107 /* one set of histograms per CPU */
108 if (data->hist)
109 free(data->hist);
110
111 free(data);
112}
113
114/*
115 * timerlat_alloc_histogram - alloc runtime data
116 */
117static struct timerlat_hist_data
118*timerlat_alloc_histogram(int nr_cpus, int entries, int bucket_size)
119{
120 struct timerlat_hist_data *data;
121 int cpu;
122
123 data = calloc(1, sizeof(*data));
124 if (!data)
125 return NULL;
126
127 data->entries = entries;
128 data->bucket_size = bucket_size;
129 data->nr_cpus = nr_cpus;
130
131 /* one set of histograms per CPU */
132 data->hist = calloc(1, sizeof(*data->hist) * nr_cpus);
133 if (!data->hist)
134 goto cleanup;
135
136 /* one histogram for IRQ and one for thread, per cpu */
137 for (cpu = 0; cpu < nr_cpus; cpu++) {
138 data->hist[cpu].irq = calloc(1, sizeof(*data->hist->irq) * (entries + 1));
139 if (!data->hist[cpu].irq)
140 goto cleanup;
141
142 data->hist[cpu].thread = calloc(1, sizeof(*data->hist->thread) * (entries + 1));
143 if (!data->hist[cpu].thread)
144 goto cleanup;
145
146 data->hist[cpu].user = calloc(1, sizeof(*data->hist->user) * (entries + 1));
147 if (!data->hist[cpu].user)
148 goto cleanup;
149 }
150
151 /* set the min to max */
152 for (cpu = 0; cpu < nr_cpus; cpu++) {
153 data->hist[cpu].min_irq = ~0;
154 data->hist[cpu].min_thread = ~0;
155 data->hist[cpu].min_user = ~0;
156 }
157
158 return data;
159
160cleanup:
161 timerlat_free_histogram(data);
162 return NULL;
163}
164
165/*
166 * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
167 */
168static void
169timerlat_hist_update(struct osnoise_tool *tool, int cpu,
170 unsigned long long context,
171 unsigned long long latency)
172{
173 struct timerlat_hist_params *params = tool->params;
174 struct timerlat_hist_data *data = tool->data;
175 int entries = data->entries;
176 int bucket;
177 int *hist;
178
179 if (params->output_divisor)
180 latency = latency / params->output_divisor;
181
182 bucket = latency / data->bucket_size;
183
184 if (!context) {
185 hist = data->hist[cpu].irq;
186 data->hist[cpu].irq_count++;
187 update_min(&data->hist[cpu].min_irq, &latency);
188 update_sum(&data->hist[cpu].sum_irq, &latency);
189 update_max(&data->hist[cpu].max_irq, &latency);
190 } else if (context == 1) {
191 hist = data->hist[cpu].thread;
192 data->hist[cpu].thread_count++;
193 update_min(&data->hist[cpu].min_thread, &latency);
194 update_sum(&data->hist[cpu].sum_thread, &latency);
195 update_max(&data->hist[cpu].max_thread, &latency);
196 } else { /* user */
197 hist = data->hist[cpu].user;
198 data->hist[cpu].user_count++;
199 update_min(&data->hist[cpu].min_user, &latency);
200 update_sum(&data->hist[cpu].sum_user, &latency);
201 update_max(&data->hist[cpu].max_user, &latency);
202 }
203
204 if (bucket < entries)
205 hist[bucket]++;
206 else
207 hist[entries]++;
208}
209
210/*
211 * timerlat_hist_handler - this is the handler for timerlat tracer events
212 */
213static int
214timerlat_hist_handler(struct trace_seq *s, struct tep_record *record,
215 struct tep_event *event, void *data)
216{
217 struct trace_instance *trace = data;
218 unsigned long long context, latency;
219 struct osnoise_tool *tool;
220 int cpu = record->cpu;
221
222 tool = container_of(trace, struct osnoise_tool, trace);
223
224 tep_get_field_val(s, event, "context", record, &context, 1);
225 tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
226
227 timerlat_hist_update(tool, cpu, context, latency);
228
229 return 0;
230}
231
232/*
233 * timerlat_hist_header - print the header of the tracer to the output
234 */
235static void timerlat_hist_header(struct osnoise_tool *tool)
236{
237 struct timerlat_hist_params *params = tool->params;
238 struct timerlat_hist_data *data = tool->data;
239 struct trace_seq *s = tool->trace.seq;
240 char duration[26];
241 int cpu;
242
243 if (params->no_header)
244 return;
245
246 get_duration(tool->start_time, duration, sizeof(duration));
247 trace_seq_printf(s, "# RTLA timerlat histogram\n");
248 trace_seq_printf(s, "# Time unit is %s (%s)\n",
249 params->output_divisor == 1 ? "nanoseconds" : "microseconds",
250 params->output_divisor == 1 ? "ns" : "us");
251
252 trace_seq_printf(s, "# Duration: %s\n", duration);
253
254 if (!params->no_index)
255 trace_seq_printf(s, "Index");
256
257 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
258 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
259 continue;
260
261 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
262 continue;
263
264 if (!params->no_irq)
265 trace_seq_printf(s, " IRQ-%03d", cpu);
266
267 if (!params->no_thread)
268 trace_seq_printf(s, " Thr-%03d", cpu);
269
270 if (params->user_hist)
271 trace_seq_printf(s, " Usr-%03d", cpu);
272 }
273 trace_seq_printf(s, "\n");
274
275
276 trace_seq_do_printf(s);
277 trace_seq_reset(s);
278}
279
280/*
281 * timerlat_print_summary - print the summary of the hist data to the output
282 */
283static void
284timerlat_print_summary(struct timerlat_hist_params *params,
285 struct trace_instance *trace,
286 struct timerlat_hist_data *data)
287{
288 int cpu;
289
290 if (params->no_summary)
291 return;
292
293 if (!params->no_index)
294 trace_seq_printf(trace->seq, "count:");
295
296 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
297 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
298 continue;
299
300 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
301 continue;
302
303 if (!params->no_irq)
304 trace_seq_printf(trace->seq, "%9d ",
305 data->hist[cpu].irq_count);
306
307 if (!params->no_thread)
308 trace_seq_printf(trace->seq, "%9d ",
309 data->hist[cpu].thread_count);
310
311 if (params->user_hist)
312 trace_seq_printf(trace->seq, "%9d ",
313 data->hist[cpu].user_count);
314 }
315 trace_seq_printf(trace->seq, "\n");
316
317 if (!params->no_index)
318 trace_seq_printf(trace->seq, "min: ");
319
320 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
321 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
322 continue;
323
324 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
325 continue;
326
327 if (!params->no_irq)
328 trace_seq_printf(trace->seq, "%9llu ",
329 data->hist[cpu].min_irq);
330
331 if (!params->no_thread)
332 trace_seq_printf(trace->seq, "%9llu ",
333 data->hist[cpu].min_thread);
334
335 if (params->user_hist)
336 trace_seq_printf(trace->seq, "%9llu ",
337 data->hist[cpu].min_user);
338 }
339 trace_seq_printf(trace->seq, "\n");
340
341 if (!params->no_index)
342 trace_seq_printf(trace->seq, "avg: ");
343
344 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
345 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
346 continue;
347
348 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
349 continue;
350
351 if (!params->no_irq) {
352 if (data->hist[cpu].irq_count)
353 trace_seq_printf(trace->seq, "%9llu ",
354 data->hist[cpu].sum_irq / data->hist[cpu].irq_count);
355 else
356 trace_seq_printf(trace->seq, " - ");
357 }
358
359 if (!params->no_thread) {
360 if (data->hist[cpu].thread_count)
361 trace_seq_printf(trace->seq, "%9llu ",
362 data->hist[cpu].sum_thread / data->hist[cpu].thread_count);
363 else
364 trace_seq_printf(trace->seq, " - ");
365 }
366
367 if (params->user_hist) {
368 if (data->hist[cpu].user_count)
369 trace_seq_printf(trace->seq, "%9llu ",
370 data->hist[cpu].sum_user / data->hist[cpu].user_count);
371 else
372 trace_seq_printf(trace->seq, " - ");
373 }
374 }
375 trace_seq_printf(trace->seq, "\n");
376
377 if (!params->no_index)
378 trace_seq_printf(trace->seq, "max: ");
379
380 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
381 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
382 continue;
383
384 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
385 continue;
386
387 if (!params->no_irq)
388 trace_seq_printf(trace->seq, "%9llu ",
389 data->hist[cpu].max_irq);
390
391 if (!params->no_thread)
392 trace_seq_printf(trace->seq, "%9llu ",
393 data->hist[cpu].max_thread);
394
395 if (params->user_hist)
396 trace_seq_printf(trace->seq, "%9llu ",
397 data->hist[cpu].max_user);
398 }
399 trace_seq_printf(trace->seq, "\n");
400 trace_seq_do_printf(trace->seq);
401 trace_seq_reset(trace->seq);
402}
403
404/*
405 * timerlat_print_stats - print data for all CPUs
406 */
407static void
408timerlat_print_stats(struct timerlat_hist_params *params, struct osnoise_tool *tool)
409{
410 struct timerlat_hist_data *data = tool->data;
411 struct trace_instance *trace = &tool->trace;
412 int bucket, cpu;
413 int total;
414
415 timerlat_hist_header(tool);
416
417 for (bucket = 0; bucket < data->entries; bucket++) {
418 total = 0;
419
420 if (!params->no_index)
421 trace_seq_printf(trace->seq, "%-6d",
422 bucket * data->bucket_size);
423
424 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
425 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
426 continue;
427
428 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
429 continue;
430
431 if (!params->no_irq) {
432 total += data->hist[cpu].irq[bucket];
433 trace_seq_printf(trace->seq, "%9d ",
434 data->hist[cpu].irq[bucket]);
435 }
436
437 if (!params->no_thread) {
438 total += data->hist[cpu].thread[bucket];
439 trace_seq_printf(trace->seq, "%9d ",
440 data->hist[cpu].thread[bucket]);
441 }
442
443 if (params->user_hist) {
444 total += data->hist[cpu].user[bucket];
445 trace_seq_printf(trace->seq, "%9d ",
446 data->hist[cpu].user[bucket]);
447 }
448
449 }
450
451 if (total == 0 && !params->with_zeros) {
452 trace_seq_reset(trace->seq);
453 continue;
454 }
455
456 trace_seq_printf(trace->seq, "\n");
457 trace_seq_do_printf(trace->seq);
458 trace_seq_reset(trace->seq);
459 }
460
461 if (!params->no_index)
462 trace_seq_printf(trace->seq, "over: ");
463
464 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
465 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
466 continue;
467
468 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
469 continue;
470
471 if (!params->no_irq)
472 trace_seq_printf(trace->seq, "%9d ",
473 data->hist[cpu].irq[data->entries]);
474
475 if (!params->no_thread)
476 trace_seq_printf(trace->seq, "%9d ",
477 data->hist[cpu].thread[data->entries]);
478
479 if (params->user_hist)
480 trace_seq_printf(trace->seq, "%9d ",
481 data->hist[cpu].user[data->entries]);
482 }
483 trace_seq_printf(trace->seq, "\n");
484 trace_seq_do_printf(trace->seq);
485 trace_seq_reset(trace->seq);
486
487 timerlat_print_summary(params, trace, data);
488}
489
490/*
491 * timerlat_hist_usage - prints timerlat top usage message
492 */
493static void timerlat_hist_usage(char *usage)
494{
495 int i;
496
497 char *msg[] = {
498 "",
499 " usage: [rtla] timerlat hist [-h] [-q] [-d s] [-D] [-n] [-a us] [-p us] [-i us] [-T us] [-s us] \\",
500 " [-t[=file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
501 " [-P priority] [-E N] [-b N] [--no-irq] [--no-thread] [--no-header] [--no-summary] \\",
502 " [--no-index] [--with-zeros] [--dma-latency us] [-C[=cgroup_name]] [--no-aa] [--dump-task] [-u]",
503 "",
504 " -h/--help: print this menu",
505 " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
506 " -p/--period us: timerlat period in us",
507 " -i/--irq us: stop trace if the irq latency is higher than the argument in us",
508 " -T/--thread us: stop trace if the thread latency is higher than the argument in us",
509 " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
510 " -c/--cpus cpus: run the tracer only on the given cpus",
511 " -H/--house-keeping cpus: run rtla control threads only on the given cpus",
512 " -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
513 " -d/--duration time[m|h|d]: duration of the session in seconds",
514 " --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)",
515 " -D/--debug: print debug info",
516 " -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]",
517 " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
518 " --filter <filter>: enable a trace event filter to the previous -e event",
519 " --trigger <trigger>: enable a trace event trigger to the previous -e event",
520 " -n/--nano: display data in nanoseconds",
521 " --no-aa: disable auto-analysis, reducing rtla timerlat cpu usage",
522 " -b/--bucket-size N: set the histogram bucket size (default 1)",
523 " -E/--entries N: set the number of entries of the histogram (default 256)",
524 " --no-irq: ignore IRQ latencies",
525 " --no-thread: ignore thread latencies",
526 " --no-header: do not print header",
527 " --no-summary: do not print summary",
528 " --no-index: do not print index",
529 " --with-zeros: print zero only entries",
530 " --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency",
531 " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
532 " o:prio - use SCHED_OTHER with prio",
533 " r:prio - use SCHED_RR with prio",
534 " f:prio - use SCHED_FIFO with prio",
535 " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period",
536 " in nanoseconds",
537 " -u/--user-threads: use rtla user-space threads instead of in-kernel timerlat threads",
538 " -U/--user-load: enable timerlat for user-defined user-space workload",
539 NULL,
540 };
541
542 if (usage)
543 fprintf(stderr, "%s\n", usage);
544
545 fprintf(stderr, "rtla timerlat hist: a per-cpu histogram of the timer latency (version %s)\n",
546 VERSION);
547
548 for (i = 0; msg[i]; i++)
549 fprintf(stderr, "%s\n", msg[i]);
550
551 if (usage)
552 exit(EXIT_FAILURE);
553
554 exit(EXIT_SUCCESS);
555}
556
557/*
558 * timerlat_hist_parse_args - allocs, parse and fill the cmd line parameters
559 */
560static struct timerlat_hist_params
561*timerlat_hist_parse_args(int argc, char *argv[])
562{
563 struct timerlat_hist_params *params;
564 struct trace_events *tevent;
565 int auto_thresh;
566 int retval;
567 int c;
568
569 params = calloc(1, sizeof(*params));
570 if (!params)
571 exit(1);
572
573 /* disabled by default */
574 params->dma_latency = -1;
575
576 /* display data in microseconds */
577 params->output_divisor = 1000;
578 params->bucket_size = 1;
579 params->entries = 256;
580
581 while (1) {
582 static struct option long_options[] = {
583 {"auto", required_argument, 0, 'a'},
584 {"cpus", required_argument, 0, 'c'},
585 {"cgroup", optional_argument, 0, 'C'},
586 {"bucket-size", required_argument, 0, 'b'},
587 {"debug", no_argument, 0, 'D'},
588 {"entries", required_argument, 0, 'E'},
589 {"duration", required_argument, 0, 'd'},
590 {"house-keeping", required_argument, 0, 'H'},
591 {"help", no_argument, 0, 'h'},
592 {"irq", required_argument, 0, 'i'},
593 {"nano", no_argument, 0, 'n'},
594 {"period", required_argument, 0, 'p'},
595 {"priority", required_argument, 0, 'P'},
596 {"stack", required_argument, 0, 's'},
597 {"thread", required_argument, 0, 'T'},
598 {"trace", optional_argument, 0, 't'},
599 {"user-threads", no_argument, 0, 'u'},
600 {"user-load", no_argument, 0, 'U'},
601 {"event", required_argument, 0, 'e'},
602 {"no-irq", no_argument, 0, '0'},
603 {"no-thread", no_argument, 0, '1'},
604 {"no-header", no_argument, 0, '2'},
605 {"no-summary", no_argument, 0, '3'},
606 {"no-index", no_argument, 0, '4'},
607 {"with-zeros", no_argument, 0, '5'},
608 {"trigger", required_argument, 0, '6'},
609 {"filter", required_argument, 0, '7'},
610 {"dma-latency", required_argument, 0, '8'},
611 {"no-aa", no_argument, 0, '9'},
612 {"dump-task", no_argument, 0, '\1'},
613 {0, 0, 0, 0}
614 };
615
616 /* getopt_long stores the option index here. */
617 int option_index = 0;
618
619 c = getopt_long(argc, argv, "a:c:C::b:d:e:E:DhH:i:np:P:s:t::T:uU0123456:7:8:9\1",
620 long_options, &option_index);
621
622 /* detect the end of the options. */
623 if (c == -1)
624 break;
625
626 switch (c) {
627 case 'a':
628 auto_thresh = get_llong_from_str(optarg);
629
630 /* set thread stop to auto_thresh */
631 params->stop_total_us = auto_thresh;
632 params->stop_us = auto_thresh;
633
634 /* get stack trace */
635 params->print_stack = auto_thresh;
636
637 /* set trace */
638 params->trace_output = "timerlat_trace.txt";
639
640 break;
641 case 'c':
642 retval = parse_cpu_set(optarg, ¶ms->monitored_cpus);
643 if (retval)
644 timerlat_hist_usage("\nInvalid -c cpu list\n");
645 params->cpus = optarg;
646 break;
647 case 'C':
648 params->cgroup = 1;
649 if (!optarg) {
650 /* will inherit this cgroup */
651 params->cgroup_name = NULL;
652 } else if (*optarg == '=') {
653 /* skip the = */
654 params->cgroup_name = ++optarg;
655 }
656 break;
657 case 'b':
658 params->bucket_size = get_llong_from_str(optarg);
659 if ((params->bucket_size == 0) || (params->bucket_size >= 1000000))
660 timerlat_hist_usage("Bucket size needs to be > 0 and <= 1000000\n");
661 break;
662 case 'D':
663 config_debug = 1;
664 break;
665 case 'd':
666 params->duration = parse_seconds_duration(optarg);
667 if (!params->duration)
668 timerlat_hist_usage("Invalid -D duration\n");
669 break;
670 case 'e':
671 tevent = trace_event_alloc(optarg);
672 if (!tevent) {
673 err_msg("Error alloc trace event");
674 exit(EXIT_FAILURE);
675 }
676
677 if (params->events)
678 tevent->next = params->events;
679
680 params->events = tevent;
681 break;
682 case 'E':
683 params->entries = get_llong_from_str(optarg);
684 if ((params->entries < 10) || (params->entries > 9999999))
685 timerlat_hist_usage("Entries must be > 10 and < 9999999\n");
686 break;
687 case 'h':
688 case '?':
689 timerlat_hist_usage(NULL);
690 break;
691 case 'H':
692 params->hk_cpus = 1;
693 retval = parse_cpu_set(optarg, ¶ms->hk_cpu_set);
694 if (retval) {
695 err_msg("Error parsing house keeping CPUs\n");
696 exit(EXIT_FAILURE);
697 }
698 break;
699 case 'i':
700 params->stop_us = get_llong_from_str(optarg);
701 break;
702 case 'n':
703 params->output_divisor = 1;
704 break;
705 case 'p':
706 params->timerlat_period_us = get_llong_from_str(optarg);
707 if (params->timerlat_period_us > 1000000)
708 timerlat_hist_usage("Period longer than 1 s\n");
709 break;
710 case 'P':
711 retval = parse_prio(optarg, ¶ms->sched_param);
712 if (retval == -1)
713 timerlat_hist_usage("Invalid -P priority");
714 params->set_sched = 1;
715 break;
716 case 's':
717 params->print_stack = get_llong_from_str(optarg);
718 break;
719 case 'T':
720 params->stop_total_us = get_llong_from_str(optarg);
721 break;
722 case 't':
723 if (optarg)
724 /* skip = */
725 params->trace_output = &optarg[1];
726 else
727 params->trace_output = "timerlat_trace.txt";
728 break;
729 case 'u':
730 params->user_workload = 1;
731 /* fallback: -u implies in -U */
732 case 'U':
733 params->user_hist = 1;
734 break;
735 case '0': /* no irq */
736 params->no_irq = 1;
737 break;
738 case '1': /* no thread */
739 params->no_thread = 1;
740 break;
741 case '2': /* no header */
742 params->no_header = 1;
743 break;
744 case '3': /* no summary */
745 params->no_summary = 1;
746 break;
747 case '4': /* no index */
748 params->no_index = 1;
749 break;
750 case '5': /* with zeros */
751 params->with_zeros = 1;
752 break;
753 case '6': /* trigger */
754 if (params->events) {
755 retval = trace_event_add_trigger(params->events, optarg);
756 if (retval) {
757 err_msg("Error adding trigger %s\n", optarg);
758 exit(EXIT_FAILURE);
759 }
760 } else {
761 timerlat_hist_usage("--trigger requires a previous -e\n");
762 }
763 break;
764 case '7': /* filter */
765 if (params->events) {
766 retval = trace_event_add_filter(params->events, optarg);
767 if (retval) {
768 err_msg("Error adding filter %s\n", optarg);
769 exit(EXIT_FAILURE);
770 }
771 } else {
772 timerlat_hist_usage("--filter requires a previous -e\n");
773 }
774 break;
775 case '8':
776 params->dma_latency = get_llong_from_str(optarg);
777 if (params->dma_latency < 0 || params->dma_latency > 10000) {
778 err_msg("--dma-latency needs to be >= 0 and < 10000");
779 exit(EXIT_FAILURE);
780 }
781 break;
782 case '9':
783 params->no_aa = 1;
784 break;
785 case '\1':
786 params->dump_tasks = 1;
787 break;
788 default:
789 timerlat_hist_usage("Invalid option");
790 }
791 }
792
793 if (geteuid()) {
794 err_msg("rtla needs root permission\n");
795 exit(EXIT_FAILURE);
796 }
797
798 if (params->no_irq && params->no_thread)
799 timerlat_hist_usage("no-irq and no-thread set, there is nothing to do here");
800
801 if (params->no_index && !params->with_zeros)
802 timerlat_hist_usage("no-index set with with-zeros is not set - it does not make sense");
803
804 /*
805 * Auto analysis only happens if stop tracing, thus:
806 */
807 if (!params->stop_us && !params->stop_total_us)
808 params->no_aa = 1;
809
810 return params;
811}
812
813/*
814 * timerlat_hist_apply_config - apply the hist configs to the initialized tool
815 */
816static int
817timerlat_hist_apply_config(struct osnoise_tool *tool, struct timerlat_hist_params *params)
818{
819 int retval, i;
820
821 if (!params->sleep_time)
822 params->sleep_time = 1;
823
824 if (params->cpus) {
825 retval = osnoise_set_cpus(tool->context, params->cpus);
826 if (retval) {
827 err_msg("Failed to apply CPUs config\n");
828 goto out_err;
829 }
830 } else {
831 for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++)
832 CPU_SET(i, ¶ms->monitored_cpus);
833 }
834
835 if (params->stop_us) {
836 retval = osnoise_set_stop_us(tool->context, params->stop_us);
837 if (retval) {
838 err_msg("Failed to set stop us\n");
839 goto out_err;
840 }
841 }
842
843 if (params->stop_total_us) {
844 retval = osnoise_set_stop_total_us(tool->context, params->stop_total_us);
845 if (retval) {
846 err_msg("Failed to set stop total us\n");
847 goto out_err;
848 }
849 }
850
851 if (params->timerlat_period_us) {
852 retval = osnoise_set_timerlat_period_us(tool->context, params->timerlat_period_us);
853 if (retval) {
854 err_msg("Failed to set timerlat period\n");
855 goto out_err;
856 }
857 }
858
859 if (params->print_stack) {
860 retval = osnoise_set_print_stack(tool->context, params->print_stack);
861 if (retval) {
862 err_msg("Failed to set print stack\n");
863 goto out_err;
864 }
865 }
866
867 if (params->hk_cpus) {
868 retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set),
869 ¶ms->hk_cpu_set);
870 if (retval == -1) {
871 err_msg("Failed to set rtla to the house keeping CPUs\n");
872 goto out_err;
873 }
874 } else if (params->cpus) {
875 /*
876 * Even if the user do not set a house-keeping CPU, try to
877 * move rtla to a CPU set different to the one where the user
878 * set the workload to run.
879 *
880 * No need to check results as this is an automatic attempt.
881 */
882 auto_house_keeping(¶ms->monitored_cpus);
883 }
884
885 if (params->user_hist) {
886 retval = osnoise_set_workload(tool->context, 0);
887 if (retval) {
888 err_msg("Failed to set OSNOISE_WORKLOAD option\n");
889 goto out_err;
890 }
891 }
892
893 return 0;
894
895out_err:
896 return -1;
897}
898
899/*
900 * timerlat_init_hist - initialize a timerlat hist tool with parameters
901 */
902static struct osnoise_tool
903*timerlat_init_hist(struct timerlat_hist_params *params)
904{
905 struct osnoise_tool *tool;
906 int nr_cpus;
907
908 nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
909
910 tool = osnoise_init_tool("timerlat_hist");
911 if (!tool)
912 return NULL;
913
914 tool->data = timerlat_alloc_histogram(nr_cpus, params->entries, params->bucket_size);
915 if (!tool->data)
916 goto out_err;
917
918 tool->params = params;
919
920 tep_register_event_handler(tool->trace.tep, -1, "ftrace", "timerlat",
921 timerlat_hist_handler, tool);
922
923 return tool;
924
925out_err:
926 osnoise_destroy_tool(tool);
927 return NULL;
928}
929
930static int stop_tracing;
931static void stop_hist(int sig)
932{
933 stop_tracing = 1;
934}
935
936/*
937 * timerlat_hist_set_signals - handles the signal to stop the tool
938 */
939static void
940timerlat_hist_set_signals(struct timerlat_hist_params *params)
941{
942 signal(SIGINT, stop_hist);
943 if (params->duration) {
944 signal(SIGALRM, stop_hist);
945 alarm(params->duration);
946 }
947}
948
949int timerlat_hist_main(int argc, char *argv[])
950{
951 struct timerlat_hist_params *params;
952 struct osnoise_tool *record = NULL;
953 struct timerlat_u_params params_u;
954 struct osnoise_tool *tool = NULL;
955 struct osnoise_tool *aa = NULL;
956 struct trace_instance *trace;
957 int dma_latency_fd = -1;
958 int return_value = 1;
959 pthread_t timerlat_u;
960 int retval;
961
962 params = timerlat_hist_parse_args(argc, argv);
963 if (!params)
964 exit(1);
965
966 tool = timerlat_init_hist(params);
967 if (!tool) {
968 err_msg("Could not init osnoise hist\n");
969 goto out_exit;
970 }
971
972 retval = timerlat_hist_apply_config(tool, params);
973 if (retval) {
974 err_msg("Could not apply config\n");
975 goto out_free;
976 }
977
978 trace = &tool->trace;
979
980 retval = enable_timerlat(trace);
981 if (retval) {
982 err_msg("Failed to enable timerlat tracer\n");
983 goto out_free;
984 }
985
986 if (params->set_sched) {
987 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param);
988 if (retval) {
989 err_msg("Failed to set sched parameters\n");
990 goto out_free;
991 }
992 }
993
994 if (params->cgroup && !params->user_workload) {
995 retval = set_comm_cgroup("timerlat/", params->cgroup_name);
996 if (!retval) {
997 err_msg("Failed to move threads to cgroup\n");
998 goto out_free;
999 }
1000 }
1001
1002 if (params->dma_latency >= 0) {
1003 dma_latency_fd = set_cpu_dma_latency(params->dma_latency);
1004 if (dma_latency_fd < 0) {
1005 err_msg("Could not set /dev/cpu_dma_latency.\n");
1006 goto out_free;
1007 }
1008 }
1009
1010 if (params->trace_output) {
1011 record = osnoise_init_trace_tool("timerlat");
1012 if (!record) {
1013 err_msg("Failed to enable the trace instance\n");
1014 goto out_free;
1015 }
1016
1017 if (params->events) {
1018 retval = trace_events_enable(&record->trace, params->events);
1019 if (retval)
1020 goto out_hist;
1021 }
1022 }
1023
1024 if (!params->no_aa) {
1025 aa = osnoise_init_tool("timerlat_aa");
1026 if (!aa)
1027 goto out_hist;
1028
1029 retval = timerlat_aa_init(aa, params->dump_tasks);
1030 if (retval) {
1031 err_msg("Failed to enable the auto analysis instance\n");
1032 goto out_hist;
1033 }
1034
1035 retval = enable_timerlat(&aa->trace);
1036 if (retval) {
1037 err_msg("Failed to enable timerlat tracer\n");
1038 goto out_hist;
1039 }
1040 }
1041
1042 /*
1043 * Start the tracers here, after having set all instances.
1044 *
1045 * Let the trace instance start first for the case of hitting a stop
1046 * tracing while enabling other instances. The trace instance is the
1047 * one with most valuable information.
1048 */
1049 if (params->trace_output)
1050 trace_instance_start(&record->trace);
1051 if (!params->no_aa)
1052 trace_instance_start(&aa->trace);
1053 trace_instance_start(trace);
1054
1055 tool->start_time = time(NULL);
1056 timerlat_hist_set_signals(params);
1057
1058 if (params->user_workload) {
1059 /* rtla asked to stop */
1060 params_u.should_run = 1;
1061 /* all threads left */
1062 params_u.stopped_running = 0;
1063
1064 params_u.set = ¶ms->monitored_cpus;
1065 if (params->set_sched)
1066 params_u.sched_param = ¶ms->sched_param;
1067 else
1068 params_u.sched_param = NULL;
1069
1070 params_u.cgroup_name = params->cgroup_name;
1071
1072 retval = pthread_create(&timerlat_u, NULL, timerlat_u_dispatcher, ¶ms_u);
1073 if (retval)
1074 err_msg("Error creating timerlat user-space threads\n");
1075 }
1076
1077 while (!stop_tracing) {
1078 sleep(params->sleep_time);
1079
1080 retval = tracefs_iterate_raw_events(trace->tep,
1081 trace->inst,
1082 NULL,
1083 0,
1084 collect_registered_events,
1085 trace);
1086 if (retval < 0) {
1087 err_msg("Error iterating on events\n");
1088 goto out_hist;
1089 }
1090
1091 if (trace_is_off(&tool->trace, &record->trace))
1092 break;
1093
1094 /* is there still any user-threads ? */
1095 if (params->user_workload) {
1096 if (params_u.stopped_running) {
1097 debug_msg("timerlat user-space threads stopped!\n");
1098 break;
1099 }
1100 }
1101 }
1102 if (params->user_workload && !params_u.stopped_running) {
1103 params_u.should_run = 0;
1104 sleep(1);
1105 }
1106
1107 timerlat_print_stats(params, tool);
1108
1109 return_value = 0;
1110
1111 if (trace_is_off(&tool->trace, &record->trace)) {
1112 printf("rtla timerlat hit stop tracing\n");
1113
1114 if (!params->no_aa)
1115 timerlat_auto_analysis(params->stop_us, params->stop_total_us);
1116
1117 if (params->trace_output) {
1118 printf(" Saving trace to %s\n", params->trace_output);
1119 save_trace_to_file(record->trace.inst, params->trace_output);
1120 }
1121 }
1122
1123out_hist:
1124 timerlat_aa_destroy();
1125 if (dma_latency_fd >= 0)
1126 close(dma_latency_fd);
1127 trace_events_destroy(&record->trace, params->events);
1128 params->events = NULL;
1129out_free:
1130 timerlat_free_histogram(tool->data);
1131 osnoise_destroy_tool(aa);
1132 osnoise_destroy_tool(record);
1133 osnoise_destroy_tool(tool);
1134 free(params);
1135out_exit:
1136 exit(return_value);
1137}