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
23 struct 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 kernel_workload;
44 int user_hist;
45 cpu_set_t hk_cpu_set;
46 struct sched_attr sched_param;
47 struct trace_events *events;
48 char no_irq;
49 char no_thread;
50 char no_header;
51 char no_summary;
52 char no_index;
53 char with_zeros;
54 int bucket_size;
55 int entries;
56 int warmup;
57 int buffer_size;
58 };
59
60 struct timerlat_hist_cpu {
61 int *irq;
62 int *thread;
63 int *user;
64
65 unsigned long long irq_count;
66 unsigned long long thread_count;
67 unsigned long long user_count;
68
69 unsigned long long min_irq;
70 unsigned long long sum_irq;
71 unsigned long long max_irq;
72
73 unsigned long long min_thread;
74 unsigned long long sum_thread;
75 unsigned long long max_thread;
76
77 unsigned long long min_user;
78 unsigned long long sum_user;
79 unsigned long long max_user;
80 };
81
82 struct timerlat_hist_data {
83 struct timerlat_hist_cpu *hist;
84 int entries;
85 int bucket_size;
86 int nr_cpus;
87 };
88
89 /*
90 * timerlat_free_histogram - free runtime data
91 */
92 static void
timerlat_free_histogram(struct timerlat_hist_data * data)93 timerlat_free_histogram(struct timerlat_hist_data *data)
94 {
95 int cpu;
96
97 /* one histogram for IRQ and one for thread, per CPU */
98 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
99 if (data->hist[cpu].irq)
100 free(data->hist[cpu].irq);
101
102 if (data->hist[cpu].thread)
103 free(data->hist[cpu].thread);
104
105 if (data->hist[cpu].user)
106 free(data->hist[cpu].user);
107
108 }
109
110 /* one set of histograms per CPU */
111 if (data->hist)
112 free(data->hist);
113
114 free(data);
115 }
116
117 /*
118 * timerlat_alloc_histogram - alloc runtime data
119 */
120 static struct timerlat_hist_data
timerlat_alloc_histogram(int nr_cpus,int entries,int bucket_size)121 *timerlat_alloc_histogram(int nr_cpus, int entries, int bucket_size)
122 {
123 struct timerlat_hist_data *data;
124 int cpu;
125
126 data = calloc(1, sizeof(*data));
127 if (!data)
128 return NULL;
129
130 data->entries = entries;
131 data->bucket_size = bucket_size;
132 data->nr_cpus = nr_cpus;
133
134 /* one set of histograms per CPU */
135 data->hist = calloc(1, sizeof(*data->hist) * nr_cpus);
136 if (!data->hist)
137 goto cleanup;
138
139 /* one histogram for IRQ and one for thread, per cpu */
140 for (cpu = 0; cpu < nr_cpus; cpu++) {
141 data->hist[cpu].irq = calloc(1, sizeof(*data->hist->irq) * (entries + 1));
142 if (!data->hist[cpu].irq)
143 goto cleanup;
144
145 data->hist[cpu].thread = calloc(1, sizeof(*data->hist->thread) * (entries + 1));
146 if (!data->hist[cpu].thread)
147 goto cleanup;
148
149 data->hist[cpu].user = calloc(1, sizeof(*data->hist->user) * (entries + 1));
150 if (!data->hist[cpu].user)
151 goto cleanup;
152 }
153
154 /* set the min to max */
155 for (cpu = 0; cpu < nr_cpus; cpu++) {
156 data->hist[cpu].min_irq = ~0;
157 data->hist[cpu].min_thread = ~0;
158 data->hist[cpu].min_user = ~0;
159 }
160
161 return data;
162
163 cleanup:
164 timerlat_free_histogram(data);
165 return NULL;
166 }
167
168 /*
169 * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
170 */
171 static void
timerlat_hist_update(struct osnoise_tool * tool,int cpu,unsigned long long context,unsigned long long latency)172 timerlat_hist_update(struct osnoise_tool *tool, int cpu,
173 unsigned long long context,
174 unsigned long long latency)
175 {
176 struct timerlat_hist_params *params = tool->params;
177 struct timerlat_hist_data *data = tool->data;
178 int entries = data->entries;
179 int bucket;
180 int *hist;
181
182 if (params->output_divisor)
183 latency = latency / params->output_divisor;
184
185 bucket = latency / data->bucket_size;
186
187 if (!context) {
188 hist = data->hist[cpu].irq;
189 data->hist[cpu].irq_count++;
190 update_min(&data->hist[cpu].min_irq, &latency);
191 update_sum(&data->hist[cpu].sum_irq, &latency);
192 update_max(&data->hist[cpu].max_irq, &latency);
193 } else if (context == 1) {
194 hist = data->hist[cpu].thread;
195 data->hist[cpu].thread_count++;
196 update_min(&data->hist[cpu].min_thread, &latency);
197 update_sum(&data->hist[cpu].sum_thread, &latency);
198 update_max(&data->hist[cpu].max_thread, &latency);
199 } else { /* user */
200 hist = data->hist[cpu].user;
201 data->hist[cpu].user_count++;
202 update_min(&data->hist[cpu].min_user, &latency);
203 update_sum(&data->hist[cpu].sum_user, &latency);
204 update_max(&data->hist[cpu].max_user, &latency);
205 }
206
207 if (bucket < entries)
208 hist[bucket]++;
209 else
210 hist[entries]++;
211 }
212
213 /*
214 * timerlat_hist_handler - this is the handler for timerlat tracer events
215 */
216 static int
timerlat_hist_handler(struct trace_seq * s,struct tep_record * record,struct tep_event * event,void * data)217 timerlat_hist_handler(struct trace_seq *s, struct tep_record *record,
218 struct tep_event *event, void *data)
219 {
220 struct trace_instance *trace = data;
221 unsigned long long context, latency;
222 struct osnoise_tool *tool;
223 int cpu = record->cpu;
224
225 tool = container_of(trace, struct osnoise_tool, trace);
226
227 tep_get_field_val(s, event, "context", record, &context, 1);
228 tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
229
230 timerlat_hist_update(tool, cpu, context, latency);
231
232 return 0;
233 }
234
235 /*
236 * timerlat_hist_header - print the header of the tracer to the output
237 */
timerlat_hist_header(struct osnoise_tool * tool)238 static void timerlat_hist_header(struct osnoise_tool *tool)
239 {
240 struct timerlat_hist_params *params = tool->params;
241 struct timerlat_hist_data *data = tool->data;
242 struct trace_seq *s = tool->trace.seq;
243 char duration[26];
244 int cpu;
245
246 if (params->no_header)
247 return;
248
249 get_duration(tool->start_time, duration, sizeof(duration));
250 trace_seq_printf(s, "# RTLA timerlat histogram\n");
251 trace_seq_printf(s, "# Time unit is %s (%s)\n",
252 params->output_divisor == 1 ? "nanoseconds" : "microseconds",
253 params->output_divisor == 1 ? "ns" : "us");
254
255 trace_seq_printf(s, "# Duration: %s\n", duration);
256
257 if (!params->no_index)
258 trace_seq_printf(s, "Index");
259
260 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
261 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
262 continue;
263
264 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
265 continue;
266
267 if (!params->no_irq)
268 trace_seq_printf(s, " IRQ-%03d", cpu);
269
270 if (!params->no_thread)
271 trace_seq_printf(s, " Thr-%03d", cpu);
272
273 if (params->user_hist)
274 trace_seq_printf(s, " Usr-%03d", cpu);
275 }
276 trace_seq_printf(s, "\n");
277
278
279 trace_seq_do_printf(s);
280 trace_seq_reset(s);
281 }
282
283 /*
284 * format_summary_value - format a line of summary value (min, max or avg)
285 * of hist data
286 */
format_summary_value(struct trace_seq * seq,int count,unsigned long long val,bool avg)287 static void format_summary_value(struct trace_seq *seq,
288 int count,
289 unsigned long long val,
290 bool avg)
291 {
292 if (count)
293 trace_seq_printf(seq, "%9llu ", avg ? val / count : val);
294 else
295 trace_seq_printf(seq, "%9c ", '-');
296 }
297
298 /*
299 * timerlat_print_summary - print the summary of the hist data to the output
300 */
301 static void
timerlat_print_summary(struct timerlat_hist_params * params,struct trace_instance * trace,struct timerlat_hist_data * data)302 timerlat_print_summary(struct timerlat_hist_params *params,
303 struct trace_instance *trace,
304 struct timerlat_hist_data *data)
305 {
306 int cpu;
307
308 if (params->no_summary)
309 return;
310
311 if (!params->no_index)
312 trace_seq_printf(trace->seq, "count:");
313
314 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
315 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
316 continue;
317
318 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
319 continue;
320
321 if (!params->no_irq)
322 trace_seq_printf(trace->seq, "%9llu ",
323 data->hist[cpu].irq_count);
324
325 if (!params->no_thread)
326 trace_seq_printf(trace->seq, "%9llu ",
327 data->hist[cpu].thread_count);
328
329 if (params->user_hist)
330 trace_seq_printf(trace->seq, "%9llu ",
331 data->hist[cpu].user_count);
332 }
333 trace_seq_printf(trace->seq, "\n");
334
335 if (!params->no_index)
336 trace_seq_printf(trace->seq, "min: ");
337
338 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
339 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
340 continue;
341
342 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
343 continue;
344
345 if (!params->no_irq)
346 format_summary_value(trace->seq,
347 data->hist[cpu].irq_count,
348 data->hist[cpu].min_irq,
349 false);
350
351 if (!params->no_thread)
352 format_summary_value(trace->seq,
353 data->hist[cpu].thread_count,
354 data->hist[cpu].min_thread,
355 false);
356
357 if (params->user_hist)
358 format_summary_value(trace->seq,
359 data->hist[cpu].user_count,
360 data->hist[cpu].min_user,
361 false);
362 }
363 trace_seq_printf(trace->seq, "\n");
364
365 if (!params->no_index)
366 trace_seq_printf(trace->seq, "avg: ");
367
368 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
369 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
370 continue;
371
372 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
373 continue;
374
375 if (!params->no_irq)
376 format_summary_value(trace->seq,
377 data->hist[cpu].irq_count,
378 data->hist[cpu].sum_irq,
379 true);
380
381 if (!params->no_thread)
382 format_summary_value(trace->seq,
383 data->hist[cpu].thread_count,
384 data->hist[cpu].sum_thread,
385 true);
386
387 if (params->user_hist)
388 format_summary_value(trace->seq,
389 data->hist[cpu].user_count,
390 data->hist[cpu].sum_user,
391 true);
392 }
393 trace_seq_printf(trace->seq, "\n");
394
395 if (!params->no_index)
396 trace_seq_printf(trace->seq, "max: ");
397
398 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
399 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
400 continue;
401
402 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
403 continue;
404
405 if (!params->no_irq)
406 format_summary_value(trace->seq,
407 data->hist[cpu].irq_count,
408 data->hist[cpu].max_irq,
409 false);
410
411 if (!params->no_thread)
412 format_summary_value(trace->seq,
413 data->hist[cpu].thread_count,
414 data->hist[cpu].max_thread,
415 false);
416
417 if (params->user_hist)
418 format_summary_value(trace->seq,
419 data->hist[cpu].user_count,
420 data->hist[cpu].max_user,
421 false);
422 }
423 trace_seq_printf(trace->seq, "\n");
424 trace_seq_do_printf(trace->seq);
425 trace_seq_reset(trace->seq);
426 }
427
428 static void
timerlat_print_stats_all(struct timerlat_hist_params * params,struct trace_instance * trace,struct timerlat_hist_data * data)429 timerlat_print_stats_all(struct timerlat_hist_params *params,
430 struct trace_instance *trace,
431 struct timerlat_hist_data *data)
432 {
433 struct timerlat_hist_cpu *cpu_data;
434 struct timerlat_hist_cpu sum;
435 int cpu;
436
437 if (params->no_summary)
438 return;
439
440 memset(&sum, 0, sizeof(sum));
441 sum.min_irq = ~0;
442 sum.min_thread = ~0;
443 sum.min_user = ~0;
444
445 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
446 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
447 continue;
448
449 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
450 continue;
451
452 cpu_data = &data->hist[cpu];
453
454 sum.irq_count += cpu_data->irq_count;
455 update_min(&sum.min_irq, &cpu_data->min_irq);
456 update_sum(&sum.sum_irq, &cpu_data->sum_irq);
457 update_max(&sum.max_irq, &cpu_data->max_irq);
458
459 sum.thread_count += cpu_data->thread_count;
460 update_min(&sum.min_thread, &cpu_data->min_thread);
461 update_sum(&sum.sum_thread, &cpu_data->sum_thread);
462 update_max(&sum.max_thread, &cpu_data->max_thread);
463
464 sum.user_count += cpu_data->user_count;
465 update_min(&sum.min_user, &cpu_data->min_user);
466 update_sum(&sum.sum_user, &cpu_data->sum_user);
467 update_max(&sum.max_user, &cpu_data->max_user);
468 }
469
470 if (!params->no_index)
471 trace_seq_printf(trace->seq, "ALL: ");
472
473 if (!params->no_irq)
474 trace_seq_printf(trace->seq, " IRQ");
475
476 if (!params->no_thread)
477 trace_seq_printf(trace->seq, " Thr");
478
479 if (params->user_hist)
480 trace_seq_printf(trace->seq, " Usr");
481
482 trace_seq_printf(trace->seq, "\n");
483
484 if (!params->no_index)
485 trace_seq_printf(trace->seq, "count:");
486
487 if (!params->no_irq)
488 trace_seq_printf(trace->seq, "%9llu ",
489 sum.irq_count);
490
491 if (!params->no_thread)
492 trace_seq_printf(trace->seq, "%9llu ",
493 sum.thread_count);
494
495 if (params->user_hist)
496 trace_seq_printf(trace->seq, "%9llu ",
497 sum.user_count);
498
499 trace_seq_printf(trace->seq, "\n");
500
501 if (!params->no_index)
502 trace_seq_printf(trace->seq, "min: ");
503
504 if (!params->no_irq)
505 format_summary_value(trace->seq,
506 sum.irq_count,
507 sum.min_irq,
508 false);
509
510 if (!params->no_thread)
511 format_summary_value(trace->seq,
512 sum.thread_count,
513 sum.min_thread,
514 false);
515
516 if (params->user_hist)
517 format_summary_value(trace->seq,
518 sum.user_count,
519 sum.min_user,
520 false);
521
522 trace_seq_printf(trace->seq, "\n");
523
524 if (!params->no_index)
525 trace_seq_printf(trace->seq, "avg: ");
526
527 if (!params->no_irq)
528 format_summary_value(trace->seq,
529 sum.irq_count,
530 sum.sum_irq,
531 true);
532
533 if (!params->no_thread)
534 format_summary_value(trace->seq,
535 sum.thread_count,
536 sum.sum_thread,
537 true);
538
539 if (params->user_hist)
540 format_summary_value(trace->seq,
541 sum.user_count,
542 sum.sum_user,
543 true);
544
545 trace_seq_printf(trace->seq, "\n");
546
547 if (!params->no_index)
548 trace_seq_printf(trace->seq, "max: ");
549
550 if (!params->no_irq)
551 format_summary_value(trace->seq,
552 sum.irq_count,
553 sum.max_irq,
554 false);
555
556 if (!params->no_thread)
557 format_summary_value(trace->seq,
558 sum.thread_count,
559 sum.max_thread,
560 false);
561
562 if (params->user_hist)
563 format_summary_value(trace->seq,
564 sum.user_count,
565 sum.max_user,
566 false);
567
568 trace_seq_printf(trace->seq, "\n");
569 trace_seq_do_printf(trace->seq);
570 trace_seq_reset(trace->seq);
571 }
572
573 /*
574 * timerlat_print_stats - print data for each CPUs
575 */
576 static void
timerlat_print_stats(struct timerlat_hist_params * params,struct osnoise_tool * tool)577 timerlat_print_stats(struct timerlat_hist_params *params, struct osnoise_tool *tool)
578 {
579 struct timerlat_hist_data *data = tool->data;
580 struct trace_instance *trace = &tool->trace;
581 int bucket, cpu;
582 int total;
583
584 timerlat_hist_header(tool);
585
586 for (bucket = 0; bucket < data->entries; bucket++) {
587 total = 0;
588
589 if (!params->no_index)
590 trace_seq_printf(trace->seq, "%-6d",
591 bucket * data->bucket_size);
592
593 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
594 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
595 continue;
596
597 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
598 continue;
599
600 if (!params->no_irq) {
601 total += data->hist[cpu].irq[bucket];
602 trace_seq_printf(trace->seq, "%9d ",
603 data->hist[cpu].irq[bucket]);
604 }
605
606 if (!params->no_thread) {
607 total += data->hist[cpu].thread[bucket];
608 trace_seq_printf(trace->seq, "%9d ",
609 data->hist[cpu].thread[bucket]);
610 }
611
612 if (params->user_hist) {
613 total += data->hist[cpu].user[bucket];
614 trace_seq_printf(trace->seq, "%9d ",
615 data->hist[cpu].user[bucket]);
616 }
617
618 }
619
620 if (total == 0 && !params->with_zeros) {
621 trace_seq_reset(trace->seq);
622 continue;
623 }
624
625 trace_seq_printf(trace->seq, "\n");
626 trace_seq_do_printf(trace->seq);
627 trace_seq_reset(trace->seq);
628 }
629
630 if (!params->no_index)
631 trace_seq_printf(trace->seq, "over: ");
632
633 for (cpu = 0; cpu < data->nr_cpus; cpu++) {
634 if (params->cpus && !CPU_ISSET(cpu, ¶ms->monitored_cpus))
635 continue;
636
637 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
638 continue;
639
640 if (!params->no_irq)
641 trace_seq_printf(trace->seq, "%9d ",
642 data->hist[cpu].irq[data->entries]);
643
644 if (!params->no_thread)
645 trace_seq_printf(trace->seq, "%9d ",
646 data->hist[cpu].thread[data->entries]);
647
648 if (params->user_hist)
649 trace_seq_printf(trace->seq, "%9d ",
650 data->hist[cpu].user[data->entries]);
651 }
652 trace_seq_printf(trace->seq, "\n");
653 trace_seq_do_printf(trace->seq);
654 trace_seq_reset(trace->seq);
655
656 timerlat_print_summary(params, trace, data);
657 timerlat_print_stats_all(params, trace, data);
658 }
659
660 /*
661 * timerlat_hist_usage - prints timerlat top usage message
662 */
timerlat_hist_usage(char * usage)663 static void timerlat_hist_usage(char *usage)
664 {
665 int i;
666
667 char *msg[] = {
668 "",
669 " usage: [rtla] timerlat hist [-h] [-q] [-d s] [-D] [-n] [-a us] [-p us] [-i us] [-T us] [-s us] \\",
670 " [-t[file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
671 " [-P priority] [-E N] [-b N] [--no-irq] [--no-thread] [--no-header] [--no-summary] \\",
672 " [--no-index] [--with-zeros] [--dma-latency us] [-C[=cgroup_name]] [--no-aa] [--dump-task] [-u|-k]",
673 " [--warm-up s]",
674 "",
675 " -h/--help: print this menu",
676 " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
677 " -p/--period us: timerlat period in us",
678 " -i/--irq us: stop trace if the irq latency is higher than the argument in us",
679 " -T/--thread us: stop trace if the thread latency is higher than the argument in us",
680 " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
681 " -c/--cpus cpus: run the tracer only on the given cpus",
682 " -H/--house-keeping cpus: run rtla control threads only on the given cpus",
683 " -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
684 " -d/--duration time[m|h|d]: duration of the session in seconds",
685 " --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)",
686 " -D/--debug: print debug info",
687 " -t/--trace[file]: save the stopped trace to [file|timerlat_trace.txt]",
688 " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
689 " --filter <filter>: enable a trace event filter to the previous -e event",
690 " --trigger <trigger>: enable a trace event trigger to the previous -e event",
691 " -n/--nano: display data in nanoseconds",
692 " --no-aa: disable auto-analysis, reducing rtla timerlat cpu usage",
693 " -b/--bucket-size N: set the histogram bucket size (default 1)",
694 " -E/--entries N: set the number of entries of the histogram (default 256)",
695 " --no-irq: ignore IRQ latencies",
696 " --no-thread: ignore thread latencies",
697 " --no-header: do not print header",
698 " --no-summary: do not print summary",
699 " --no-index: do not print index",
700 " --with-zeros: print zero only entries",
701 " --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency",
702 " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
703 " o:prio - use SCHED_OTHER with prio",
704 " r:prio - use SCHED_RR with prio",
705 " f:prio - use SCHED_FIFO with prio",
706 " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period",
707 " in nanoseconds",
708 " -u/--user-threads: use rtla user-space threads instead of kernel-space timerlat threads",
709 " -k/--kernel-threads: use timerlat kernel-space threads instead of rtla user-space threads",
710 " -U/--user-load: enable timerlat for user-defined user-space workload",
711 " --warm-up s: let the workload run for s seconds before collecting data",
712 " --trace-buffer-size kB: set the per-cpu trace buffer size in kB",
713 NULL,
714 };
715
716 if (usage)
717 fprintf(stderr, "%s\n", usage);
718
719 fprintf(stderr, "rtla timerlat hist: a per-cpu histogram of the timer latency (version %s)\n",
720 VERSION);
721
722 for (i = 0; msg[i]; i++)
723 fprintf(stderr, "%s\n", msg[i]);
724
725 if (usage)
726 exit(EXIT_FAILURE);
727
728 exit(EXIT_SUCCESS);
729 }
730
731 /*
732 * timerlat_hist_parse_args - allocs, parse and fill the cmd line parameters
733 */
734 static struct timerlat_hist_params
timerlat_hist_parse_args(int argc,char * argv[])735 *timerlat_hist_parse_args(int argc, char *argv[])
736 {
737 struct timerlat_hist_params *params;
738 struct trace_events *tevent;
739 int auto_thresh;
740 int retval;
741 int c;
742
743 params = calloc(1, sizeof(*params));
744 if (!params)
745 exit(1);
746
747 /* disabled by default */
748 params->dma_latency = -1;
749
750 /* display data in microseconds */
751 params->output_divisor = 1000;
752 params->bucket_size = 1;
753 params->entries = 256;
754
755 while (1) {
756 static struct option long_options[] = {
757 {"auto", required_argument, 0, 'a'},
758 {"cpus", required_argument, 0, 'c'},
759 {"cgroup", optional_argument, 0, 'C'},
760 {"bucket-size", required_argument, 0, 'b'},
761 {"debug", no_argument, 0, 'D'},
762 {"entries", required_argument, 0, 'E'},
763 {"duration", required_argument, 0, 'd'},
764 {"house-keeping", required_argument, 0, 'H'},
765 {"help", no_argument, 0, 'h'},
766 {"irq", required_argument, 0, 'i'},
767 {"nano", no_argument, 0, 'n'},
768 {"period", required_argument, 0, 'p'},
769 {"priority", required_argument, 0, 'P'},
770 {"stack", required_argument, 0, 's'},
771 {"thread", required_argument, 0, 'T'},
772 {"trace", optional_argument, 0, 't'},
773 {"user-threads", no_argument, 0, 'u'},
774 {"kernel-threads", no_argument, 0, 'k'},
775 {"user-load", no_argument, 0, 'U'},
776 {"event", required_argument, 0, 'e'},
777 {"no-irq", no_argument, 0, '0'},
778 {"no-thread", no_argument, 0, '1'},
779 {"no-header", no_argument, 0, '2'},
780 {"no-summary", no_argument, 0, '3'},
781 {"no-index", no_argument, 0, '4'},
782 {"with-zeros", no_argument, 0, '5'},
783 {"trigger", required_argument, 0, '6'},
784 {"filter", required_argument, 0, '7'},
785 {"dma-latency", required_argument, 0, '8'},
786 {"no-aa", no_argument, 0, '9'},
787 {"dump-task", no_argument, 0, '\1'},
788 {"warm-up", required_argument, 0, '\2'},
789 {"trace-buffer-size", required_argument, 0, '\3'},
790 {0, 0, 0, 0}
791 };
792
793 /* getopt_long stores the option index here. */
794 int option_index = 0;
795
796 c = getopt_long(argc, argv, "a:c:C::b:d:e:E:DhH:i:knp:P:s:t::T:uU0123456:7:8:9\1\2:\3:",
797 long_options, &option_index);
798
799 /* detect the end of the options. */
800 if (c == -1)
801 break;
802
803 switch (c) {
804 case 'a':
805 auto_thresh = get_llong_from_str(optarg);
806
807 /* set thread stop to auto_thresh */
808 params->stop_total_us = auto_thresh;
809 params->stop_us = auto_thresh;
810
811 /* get stack trace */
812 params->print_stack = auto_thresh;
813
814 /* set trace */
815 params->trace_output = "timerlat_trace.txt";
816
817 break;
818 case 'c':
819 retval = parse_cpu_set(optarg, ¶ms->monitored_cpus);
820 if (retval)
821 timerlat_hist_usage("\nInvalid -c cpu list\n");
822 params->cpus = optarg;
823 break;
824 case 'C':
825 params->cgroup = 1;
826 if (!optarg) {
827 /* will inherit this cgroup */
828 params->cgroup_name = NULL;
829 } else if (*optarg == '=') {
830 /* skip the = */
831 params->cgroup_name = ++optarg;
832 }
833 break;
834 case 'b':
835 params->bucket_size = get_llong_from_str(optarg);
836 if ((params->bucket_size == 0) || (params->bucket_size >= 1000000))
837 timerlat_hist_usage("Bucket size needs to be > 0 and <= 1000000\n");
838 break;
839 case 'D':
840 config_debug = 1;
841 break;
842 case 'd':
843 params->duration = parse_seconds_duration(optarg);
844 if (!params->duration)
845 timerlat_hist_usage("Invalid -D duration\n");
846 break;
847 case 'e':
848 tevent = trace_event_alloc(optarg);
849 if (!tevent) {
850 err_msg("Error alloc trace event");
851 exit(EXIT_FAILURE);
852 }
853
854 if (params->events)
855 tevent->next = params->events;
856
857 params->events = tevent;
858 break;
859 case 'E':
860 params->entries = get_llong_from_str(optarg);
861 if ((params->entries < 10) || (params->entries > 9999999))
862 timerlat_hist_usage("Entries must be > 10 and < 9999999\n");
863 break;
864 case 'h':
865 case '?':
866 timerlat_hist_usage(NULL);
867 break;
868 case 'H':
869 params->hk_cpus = 1;
870 retval = parse_cpu_set(optarg, ¶ms->hk_cpu_set);
871 if (retval) {
872 err_msg("Error parsing house keeping CPUs\n");
873 exit(EXIT_FAILURE);
874 }
875 break;
876 case 'i':
877 params->stop_us = get_llong_from_str(optarg);
878 break;
879 case 'k':
880 params->kernel_workload = 1;
881 break;
882 case 'n':
883 params->output_divisor = 1;
884 break;
885 case 'p':
886 params->timerlat_period_us = get_llong_from_str(optarg);
887 if (params->timerlat_period_us > 1000000)
888 timerlat_hist_usage("Period longer than 1 s\n");
889 break;
890 case 'P':
891 retval = parse_prio(optarg, ¶ms->sched_param);
892 if (retval == -1)
893 timerlat_hist_usage("Invalid -P priority");
894 params->set_sched = 1;
895 break;
896 case 's':
897 params->print_stack = get_llong_from_str(optarg);
898 break;
899 case 'T':
900 params->stop_total_us = get_llong_from_str(optarg);
901 break;
902 case 't':
903 if (optarg) {
904 if (optarg[0] == '=')
905 params->trace_output = &optarg[1];
906 else
907 params->trace_output = &optarg[0];
908 } else if (optind < argc && argv[optind][0] != '-')
909 params->trace_output = argv[optind];
910 else
911 params->trace_output = "timerlat_trace.txt";
912 break;
913 case 'u':
914 params->user_workload = 1;
915 /* fallback: -u implies in -U */
916 case 'U':
917 params->user_hist = 1;
918 break;
919 case '0': /* no irq */
920 params->no_irq = 1;
921 break;
922 case '1': /* no thread */
923 params->no_thread = 1;
924 break;
925 case '2': /* no header */
926 params->no_header = 1;
927 break;
928 case '3': /* no summary */
929 params->no_summary = 1;
930 break;
931 case '4': /* no index */
932 params->no_index = 1;
933 break;
934 case '5': /* with zeros */
935 params->with_zeros = 1;
936 break;
937 case '6': /* trigger */
938 if (params->events) {
939 retval = trace_event_add_trigger(params->events, optarg);
940 if (retval) {
941 err_msg("Error adding trigger %s\n", optarg);
942 exit(EXIT_FAILURE);
943 }
944 } else {
945 timerlat_hist_usage("--trigger requires a previous -e\n");
946 }
947 break;
948 case '7': /* filter */
949 if (params->events) {
950 retval = trace_event_add_filter(params->events, optarg);
951 if (retval) {
952 err_msg("Error adding filter %s\n", optarg);
953 exit(EXIT_FAILURE);
954 }
955 } else {
956 timerlat_hist_usage("--filter requires a previous -e\n");
957 }
958 break;
959 case '8':
960 params->dma_latency = get_llong_from_str(optarg);
961 if (params->dma_latency < 0 || params->dma_latency > 10000) {
962 err_msg("--dma-latency needs to be >= 0 and < 10000");
963 exit(EXIT_FAILURE);
964 }
965 break;
966 case '9':
967 params->no_aa = 1;
968 break;
969 case '\1':
970 params->dump_tasks = 1;
971 break;
972 case '\2':
973 params->warmup = get_llong_from_str(optarg);
974 break;
975 case '\3':
976 params->buffer_size = get_llong_from_str(optarg);
977 break;
978 default:
979 timerlat_hist_usage("Invalid option");
980 }
981 }
982
983 if (geteuid()) {
984 err_msg("rtla needs root permission\n");
985 exit(EXIT_FAILURE);
986 }
987
988 if (params->no_irq && params->no_thread)
989 timerlat_hist_usage("no-irq and no-thread set, there is nothing to do here");
990
991 if (params->no_index && !params->with_zeros)
992 timerlat_hist_usage("no-index set with with-zeros is not set - it does not make sense");
993
994 /*
995 * Auto analysis only happens if stop tracing, thus:
996 */
997 if (!params->stop_us && !params->stop_total_us)
998 params->no_aa = 1;
999
1000 if (params->kernel_workload && params->user_workload)
1001 timerlat_hist_usage("--kernel-threads and --user-threads are mutually exclusive!");
1002
1003 return params;
1004 }
1005
1006 /*
1007 * timerlat_hist_apply_config - apply the hist configs to the initialized tool
1008 */
1009 static int
timerlat_hist_apply_config(struct osnoise_tool * tool,struct timerlat_hist_params * params)1010 timerlat_hist_apply_config(struct osnoise_tool *tool, struct timerlat_hist_params *params)
1011 {
1012 int retval, i;
1013
1014 if (!params->sleep_time)
1015 params->sleep_time = 1;
1016
1017 if (params->cpus) {
1018 retval = osnoise_set_cpus(tool->context, params->cpus);
1019 if (retval) {
1020 err_msg("Failed to apply CPUs config\n");
1021 goto out_err;
1022 }
1023 } else {
1024 for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++)
1025 CPU_SET(i, ¶ms->monitored_cpus);
1026 }
1027
1028 if (params->stop_us) {
1029 retval = osnoise_set_stop_us(tool->context, params->stop_us);
1030 if (retval) {
1031 err_msg("Failed to set stop us\n");
1032 goto out_err;
1033 }
1034 }
1035
1036 if (params->stop_total_us) {
1037 retval = osnoise_set_stop_total_us(tool->context, params->stop_total_us);
1038 if (retval) {
1039 err_msg("Failed to set stop total us\n");
1040 goto out_err;
1041 }
1042 }
1043
1044 if (params->timerlat_period_us) {
1045 retval = osnoise_set_timerlat_period_us(tool->context, params->timerlat_period_us);
1046 if (retval) {
1047 err_msg("Failed to set timerlat period\n");
1048 goto out_err;
1049 }
1050 }
1051
1052 if (params->print_stack) {
1053 retval = osnoise_set_print_stack(tool->context, params->print_stack);
1054 if (retval) {
1055 err_msg("Failed to set print stack\n");
1056 goto out_err;
1057 }
1058 }
1059
1060 if (params->hk_cpus) {
1061 retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set),
1062 ¶ms->hk_cpu_set);
1063 if (retval == -1) {
1064 err_msg("Failed to set rtla to the house keeping CPUs\n");
1065 goto out_err;
1066 }
1067 } else if (params->cpus) {
1068 /*
1069 * Even if the user do not set a house-keeping CPU, try to
1070 * move rtla to a CPU set different to the one where the user
1071 * set the workload to run.
1072 *
1073 * No need to check results as this is an automatic attempt.
1074 */
1075 auto_house_keeping(¶ms->monitored_cpus);
1076 }
1077
1078 /*
1079 * If the user did not specify a type of thread, try user-threads first.
1080 * Fall back to kernel threads otherwise.
1081 */
1082 if (!params->kernel_workload && !params->user_hist) {
1083 retval = tracefs_file_exists(NULL, "osnoise/per_cpu/cpu0/timerlat_fd");
1084 if (retval) {
1085 debug_msg("User-space interface detected, setting user-threads\n");
1086 params->user_workload = 1;
1087 params->user_hist = 1;
1088 } else {
1089 debug_msg("User-space interface not detected, setting kernel-threads\n");
1090 params->kernel_workload = 1;
1091 }
1092 }
1093
1094 /*
1095 * Set workload according to type of thread if the kernel supports it.
1096 * On kernels without support, user threads will have already failed
1097 * on missing timerlat_fd, and kernel threads do not need it.
1098 */
1099 retval = osnoise_set_workload(tool->context, params->kernel_workload);
1100 if (retval < -1) {
1101 err_msg("Failed to set OSNOISE_WORKLOAD option\n");
1102 goto out_err;
1103 }
1104
1105 return 0;
1106
1107 out_err:
1108 return -1;
1109 }
1110
1111 /*
1112 * timerlat_init_hist - initialize a timerlat hist tool with parameters
1113 */
1114 static struct osnoise_tool
timerlat_init_hist(struct timerlat_hist_params * params)1115 *timerlat_init_hist(struct timerlat_hist_params *params)
1116 {
1117 struct osnoise_tool *tool;
1118 int nr_cpus;
1119
1120 nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
1121
1122 tool = osnoise_init_tool("timerlat_hist");
1123 if (!tool)
1124 return NULL;
1125
1126 tool->data = timerlat_alloc_histogram(nr_cpus, params->entries, params->bucket_size);
1127 if (!tool->data)
1128 goto out_err;
1129
1130 tool->params = params;
1131
1132 tep_register_event_handler(tool->trace.tep, -1, "ftrace", "timerlat",
1133 timerlat_hist_handler, tool);
1134
1135 return tool;
1136
1137 out_err:
1138 osnoise_destroy_tool(tool);
1139 return NULL;
1140 }
1141
1142 static int stop_tracing;
1143 static struct trace_instance *hist_inst = NULL;
stop_hist(int sig)1144 static void stop_hist(int sig)
1145 {
1146 if (stop_tracing) {
1147 /*
1148 * Stop requested twice in a row; abort event processing and
1149 * exit immediately
1150 */
1151 tracefs_iterate_stop(hist_inst->inst);
1152 return;
1153 }
1154 stop_tracing = 1;
1155 if (hist_inst)
1156 trace_instance_stop(hist_inst);
1157 }
1158
1159 /*
1160 * timerlat_hist_set_signals - handles the signal to stop the tool
1161 */
1162 static void
timerlat_hist_set_signals(struct timerlat_hist_params * params)1163 timerlat_hist_set_signals(struct timerlat_hist_params *params)
1164 {
1165 signal(SIGINT, stop_hist);
1166 if (params->duration) {
1167 signal(SIGALRM, stop_hist);
1168 alarm(params->duration);
1169 }
1170 }
1171
timerlat_hist_main(int argc,char * argv[])1172 int timerlat_hist_main(int argc, char *argv[])
1173 {
1174 struct timerlat_hist_params *params;
1175 struct osnoise_tool *record = NULL;
1176 struct timerlat_u_params params_u;
1177 struct osnoise_tool *tool = NULL;
1178 struct osnoise_tool *aa = NULL;
1179 struct trace_instance *trace;
1180 int dma_latency_fd = -1;
1181 int return_value = 1;
1182 pthread_t timerlat_u;
1183 int retval;
1184
1185 params = timerlat_hist_parse_args(argc, argv);
1186 if (!params)
1187 exit(1);
1188
1189 tool = timerlat_init_hist(params);
1190 if (!tool) {
1191 err_msg("Could not init osnoise hist\n");
1192 goto out_exit;
1193 }
1194
1195 retval = timerlat_hist_apply_config(tool, params);
1196 if (retval) {
1197 err_msg("Could not apply config\n");
1198 goto out_free;
1199 }
1200
1201 trace = &tool->trace;
1202 /*
1203 * Save trace instance into global variable so that SIGINT can stop
1204 * the timerlat tracer.
1205 * Otherwise, rtla could loop indefinitely when overloaded.
1206 */
1207 hist_inst = trace;
1208
1209 retval = enable_timerlat(trace);
1210 if (retval) {
1211 err_msg("Failed to enable timerlat tracer\n");
1212 goto out_free;
1213 }
1214
1215 if (params->set_sched) {
1216 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param);
1217 if (retval) {
1218 err_msg("Failed to set sched parameters\n");
1219 goto out_free;
1220 }
1221 }
1222
1223 if (params->cgroup && !params->user_workload) {
1224 retval = set_comm_cgroup("timerlat/", params->cgroup_name);
1225 if (!retval) {
1226 err_msg("Failed to move threads to cgroup\n");
1227 goto out_free;
1228 }
1229 }
1230
1231 if (params->dma_latency >= 0) {
1232 dma_latency_fd = set_cpu_dma_latency(params->dma_latency);
1233 if (dma_latency_fd < 0) {
1234 err_msg("Could not set /dev/cpu_dma_latency.\n");
1235 goto out_free;
1236 }
1237 }
1238
1239 if (params->trace_output) {
1240 record = osnoise_init_trace_tool("timerlat");
1241 if (!record) {
1242 err_msg("Failed to enable the trace instance\n");
1243 goto out_free;
1244 }
1245
1246 if (params->events) {
1247 retval = trace_events_enable(&record->trace, params->events);
1248 if (retval)
1249 goto out_hist;
1250 }
1251
1252 if (params->buffer_size > 0) {
1253 retval = trace_set_buffer_size(&record->trace, params->buffer_size);
1254 if (retval)
1255 goto out_hist;
1256 }
1257 }
1258
1259 if (!params->no_aa) {
1260 aa = osnoise_init_tool("timerlat_aa");
1261 if (!aa)
1262 goto out_hist;
1263
1264 retval = timerlat_aa_init(aa, params->dump_tasks);
1265 if (retval) {
1266 err_msg("Failed to enable the auto analysis instance\n");
1267 goto out_hist;
1268 }
1269
1270 retval = enable_timerlat(&aa->trace);
1271 if (retval) {
1272 err_msg("Failed to enable timerlat tracer\n");
1273 goto out_hist;
1274 }
1275 }
1276
1277 if (params->user_workload) {
1278 /* rtla asked to stop */
1279 params_u.should_run = 1;
1280 /* all threads left */
1281 params_u.stopped_running = 0;
1282
1283 params_u.set = ¶ms->monitored_cpus;
1284 if (params->set_sched)
1285 params_u.sched_param = ¶ms->sched_param;
1286 else
1287 params_u.sched_param = NULL;
1288
1289 params_u.cgroup_name = params->cgroup_name;
1290
1291 retval = pthread_create(&timerlat_u, NULL, timerlat_u_dispatcher, ¶ms_u);
1292 if (retval)
1293 err_msg("Error creating timerlat user-space threads\n");
1294 }
1295
1296 if (params->warmup > 0) {
1297 debug_msg("Warming up for %d seconds\n", params->warmup);
1298 sleep(params->warmup);
1299 if (stop_tracing)
1300 goto out_hist;
1301 }
1302
1303 /*
1304 * Start the tracers here, after having set all instances.
1305 *
1306 * Let the trace instance start first for the case of hitting a stop
1307 * tracing while enabling other instances. The trace instance is the
1308 * one with most valuable information.
1309 */
1310 if (params->trace_output)
1311 trace_instance_start(&record->trace);
1312 if (!params->no_aa)
1313 trace_instance_start(&aa->trace);
1314 trace_instance_start(trace);
1315
1316 tool->start_time = time(NULL);
1317 timerlat_hist_set_signals(params);
1318
1319 while (!stop_tracing) {
1320 sleep(params->sleep_time);
1321
1322 retval = tracefs_iterate_raw_events(trace->tep,
1323 trace->inst,
1324 NULL,
1325 0,
1326 collect_registered_events,
1327 trace);
1328 if (retval < 0) {
1329 err_msg("Error iterating on events\n");
1330 goto out_hist;
1331 }
1332
1333 if (trace_is_off(&tool->trace, &record->trace))
1334 break;
1335
1336 /* is there still any user-threads ? */
1337 if (params->user_workload) {
1338 if (params_u.stopped_running) {
1339 debug_msg("timerlat user-space threads stopped!\n");
1340 break;
1341 }
1342 }
1343 }
1344
1345 if (params->user_workload && !params_u.stopped_running) {
1346 params_u.should_run = 0;
1347 sleep(1);
1348 }
1349
1350 timerlat_print_stats(params, tool);
1351
1352 return_value = 0;
1353
1354 if (trace_is_off(&tool->trace, &record->trace) && !stop_tracing) {
1355 printf("rtla timerlat hit stop tracing\n");
1356
1357 if (!params->no_aa)
1358 timerlat_auto_analysis(params->stop_us, params->stop_total_us);
1359
1360 if (params->trace_output) {
1361 printf(" Saving trace to %s\n", params->trace_output);
1362 save_trace_to_file(record->trace.inst, params->trace_output);
1363 }
1364 }
1365
1366 out_hist:
1367 timerlat_aa_destroy();
1368 if (dma_latency_fd >= 0)
1369 close(dma_latency_fd);
1370 trace_events_destroy(&record->trace, params->events);
1371 params->events = NULL;
1372 out_free:
1373 timerlat_free_histogram(tool->data);
1374 osnoise_destroy_tool(aa);
1375 osnoise_destroy_tool(record);
1376 osnoise_destroy_tool(tool);
1377 free(params);
1378 out_exit:
1379 exit(return_value);
1380 }
1381