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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira <[email protected]>
4 */
5
6#define _GNU_SOURCE
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#include <sched.h>
14#include <pthread.h>
15
16#include "timerlat.h"
17#include "timerlat_aa.h"
18#include "timerlat_bpf.h"
19#include "cli.h"
20#include "common.h"
21
22struct timerlat_hist_cpu {
23 int *irq;
24 int *thread;
25 int *user;
26
27 unsigned long long irq_count;
28 unsigned long long thread_count;
29 unsigned long long user_count;
30
31 unsigned long long min_irq;
32 unsigned long long sum_irq;
33 unsigned long long max_irq;
34
35 unsigned long long min_thread;
36 unsigned long long sum_thread;
37 unsigned long long max_thread;
38
39 unsigned long long min_user;
40 unsigned long long sum_user;
41 unsigned long long max_user;
42};
43
44struct timerlat_hist_data {
45 struct timerlat_hist_cpu *hist;
46 int entries;
47 int bucket_size;
48};
49
50/*
51 * timerlat_free_histogram - free runtime data
52 */
53static void
54timerlat_free_histogram(struct timerlat_hist_data *data)
55{
56 int cpu;
57
58 /* one histogram for IRQ and one for thread, per CPU */
59 for (cpu = 0; cpu < nr_cpus; cpu++) {
60 if (data->hist[cpu].irq)
61 free(data->hist[cpu].irq);
62
63 if (data->hist[cpu].thread)
64 free(data->hist[cpu].thread);
65
66 if (data->hist[cpu].user)
67 free(data->hist[cpu].user);
68
69 }
70
71 /* one set of histograms per CPU */
72 if (data->hist)
73 free(data->hist);
74}
75
76static void timerlat_free_histogram_tool(struct osnoise_tool *tool)
77{
78 timerlat_free_histogram(tool->data);
79 timerlat_free(tool);
80}
81
82/*
83 * timerlat_alloc_histogram - alloc runtime data
84 */
85static struct timerlat_hist_data
86*timerlat_alloc_histogram(int entries, int bucket_size)
87{
88 struct timerlat_hist_data *data;
89 int cpu;
90
91 data = calloc(1, sizeof(*data));
92 if (!data)
93 return NULL;
94
95 data->entries = entries;
96 data->bucket_size = bucket_size;
97
98 /* one set of histograms per CPU */
99 data->hist = calloc(1, sizeof(*data->hist) * nr_cpus);
100 if (!data->hist)
101 goto cleanup;
102
103 /* one histogram for IRQ and one for thread, per cpu */
104 for (cpu = 0; cpu < nr_cpus; cpu++) {
105 data->hist[cpu].irq = calloc(1, sizeof(*data->hist->irq) * (entries + 1));
106 if (!data->hist[cpu].irq)
107 goto cleanup;
108
109 data->hist[cpu].thread = calloc(1, sizeof(*data->hist->thread) * (entries + 1));
110 if (!data->hist[cpu].thread)
111 goto cleanup;
112
113 data->hist[cpu].user = calloc(1, sizeof(*data->hist->user) * (entries + 1));
114 if (!data->hist[cpu].user)
115 goto cleanup;
116 }
117
118 /* set the min to max */
119 for (cpu = 0; cpu < nr_cpus; cpu++) {
120 data->hist[cpu].min_irq = ~0;
121 data->hist[cpu].min_thread = ~0;
122 data->hist[cpu].min_user = ~0;
123 }
124
125 return data;
126
127cleanup:
128 timerlat_free_histogram(data);
129 return NULL;
130}
131
132/*
133 * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
134 */
135static void
136timerlat_hist_update(struct osnoise_tool *tool, int cpu,
137 unsigned long long context,
138 unsigned long long latency)
139{
140 struct timerlat_params *params = to_timerlat_params(tool->params);
141 struct timerlat_hist_data *data = tool->data;
142 int entries = data->entries;
143 int bucket;
144 int *hist;
145
146 if (params->common.output_divisor)
147 latency = latency / params->common.output_divisor;
148
149 bucket = latency / data->bucket_size;
150
151 if (!context) {
152 hist = data->hist[cpu].irq;
153 data->hist[cpu].irq_count++;
154 update_min(&data->hist[cpu].min_irq, &latency);
155 update_sum(&data->hist[cpu].sum_irq, &latency);
156 update_max(&data->hist[cpu].max_irq, &latency);
157 } else if (context == 1) {
158 hist = data->hist[cpu].thread;
159 data->hist[cpu].thread_count++;
160 update_min(&data->hist[cpu].min_thread, &latency);
161 update_sum(&data->hist[cpu].sum_thread, &latency);
162 update_max(&data->hist[cpu].max_thread, &latency);
163 } else { /* user */
164 hist = data->hist[cpu].user;
165 data->hist[cpu].user_count++;
166 update_min(&data->hist[cpu].min_user, &latency);
167 update_sum(&data->hist[cpu].sum_user, &latency);
168 update_max(&data->hist[cpu].max_user, &latency);
169 }
170
171 if (bucket < entries)
172 hist[bucket]++;
173 else
174 hist[entries]++;
175}
176
177/*
178 * timerlat_hist_handler - this is the handler for timerlat tracer events
179 */
180static int
181timerlat_hist_handler(struct trace_seq *s, struct tep_record *record,
182 struct tep_event *event, void *data)
183{
184 struct trace_instance *trace = data;
185 unsigned long long context, latency;
186 struct osnoise_tool *tool;
187 int cpu = record->cpu;
188
189 tool = container_of(trace, struct osnoise_tool, trace);
190
191 tep_get_field_val(s, event, "context", record, &context, 1);
192 tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
193
194 timerlat_hist_update(tool, cpu, context, latency);
195
196 return 0;
197}
198
199/*
200 * timerlat_hist_bpf_pull_data - copy data from BPF maps into userspace
201 */
202static int timerlat_hist_bpf_pull_data(struct osnoise_tool *tool)
203{
204 struct timerlat_hist_data *data = tool->data;
205 int i, j, err;
206 long long value_irq[nr_cpus],
207 value_thread[nr_cpus],
208 value_user[nr_cpus];
209
210 /* Pull histogram */
211 for (i = 0; i < data->entries; i++) {
212 err = timerlat_bpf_get_hist_value(i, value_irq, value_thread,
213 value_user);
214 if (err)
215 return err;
216 for (j = 0; j < nr_cpus; j++) {
217 data->hist[j].irq[i] = value_irq[j];
218 data->hist[j].thread[i] = value_thread[j];
219 data->hist[j].user[i] = value_user[j];
220 }
221 }
222
223 /* Pull summary */
224 err = timerlat_bpf_get_summary_value(SUMMARY_COUNT,
225 value_irq, value_thread, value_user);
226 if (err)
227 return err;
228 for (i = 0; i < nr_cpus; i++) {
229 data->hist[i].irq_count = value_irq[i];
230 data->hist[i].thread_count = value_thread[i];
231 data->hist[i].user_count = value_user[i];
232 }
233
234 err = timerlat_bpf_get_summary_value(SUMMARY_MIN,
235 value_irq, value_thread, value_user);
236 if (err)
237 return err;
238 for (i = 0; i < nr_cpus; i++) {
239 data->hist[i].min_irq = value_irq[i];
240 data->hist[i].min_thread = value_thread[i];
241 data->hist[i].min_user = value_user[i];
242 }
243
244 err = timerlat_bpf_get_summary_value(SUMMARY_MAX,
245 value_irq, value_thread, value_user);
246 if (err)
247 return err;
248 for (i = 0; i < nr_cpus; i++) {
249 data->hist[i].max_irq = value_irq[i];
250 data->hist[i].max_thread = value_thread[i];
251 data->hist[i].max_user = value_user[i];
252 }
253
254 err = timerlat_bpf_get_summary_value(SUMMARY_SUM,
255 value_irq, value_thread, value_user);
256 if (err)
257 return err;
258 for (i = 0; i < nr_cpus; i++) {
259 data->hist[i].sum_irq = value_irq[i];
260 data->hist[i].sum_thread = value_thread[i];
261 data->hist[i].sum_user = value_user[i];
262 }
263
264 err = timerlat_bpf_get_summary_value(SUMMARY_OVERFLOW,
265 value_irq, value_thread, value_user);
266 if (err)
267 return err;
268 for (i = 0; i < nr_cpus; i++) {
269 data->hist[i].irq[data->entries] = value_irq[i];
270 data->hist[i].thread[data->entries] = value_thread[i];
271 data->hist[i].user[data->entries] = value_user[i];
272 }
273
274 return 0;
275}
276
277/*
278 * timerlat_hist_header - print the header of the tracer to the output
279 */
280static void timerlat_hist_header(struct osnoise_tool *tool)
281{
282 struct timerlat_params *params = to_timerlat_params(tool->params);
283 struct timerlat_hist_data *data = tool->data;
284 struct trace_seq *s = tool->trace.seq;
285 char duration[26];
286 int cpu;
287
288 if (params->common.hist.no_header)
289 return;
290
291 get_duration(tool->start_time, duration, sizeof(duration));
292 trace_seq_printf(s, "# RTLA timerlat histogram\n");
293 trace_seq_printf(s, "# Time unit is %s (%s)\n",
294 params->common.output_divisor == 1 ? "nanoseconds" : "microseconds",
295 params->common.output_divisor == 1 ? "ns" : "us");
296
297 trace_seq_printf(s, "# Duration: %s\n", duration);
298
299 if (!params->common.hist.no_index)
300 trace_seq_printf(s, "Index");
301
302 for_each_monitored_cpu(cpu, &params->common) {
303
304 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
305 continue;
306
307 if (!params->common.hist.no_irq)
308 trace_seq_printf(s, " IRQ-%03d", cpu);
309
310 if (!params->common.hist.no_thread)
311 trace_seq_printf(s, " Thr-%03d", cpu);
312
313 if (params->common.user_data)
314 trace_seq_printf(s, " Usr-%03d", cpu);
315 }
316 trace_seq_printf(s, "\n");
317
318
319 trace_seq_do_printf(s);
320 trace_seq_reset(s);
321}
322
323/*
324 * format_summary_value - format a line of summary value (min, max or avg)
325 * of hist data
326 */
327static void format_summary_value(struct trace_seq *seq,
328 int count,
329 unsigned long long val,
330 bool avg)
331{
332 if (count)
333 trace_seq_printf(seq, "%9llu ", avg ? val / count : val);
334 else
335 trace_seq_printf(seq, "%9c ", '-');
336}
337
338/*
339 * timerlat_print_summary - print the summary of the hist data to the output
340 */
341static void
342timerlat_print_summary(struct timerlat_params *params,
343 struct trace_instance *trace,
344 struct timerlat_hist_data *data)
345{
346 int cpu;
347
348 if (params->common.hist.no_summary)
349 return;
350
351 if (!params->common.hist.no_index)
352 trace_seq_printf(trace->seq, "count:");
353
354 for_each_monitored_cpu(cpu, &params->common) {
355
356 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
357 continue;
358
359 if (!params->common.hist.no_irq)
360 trace_seq_printf(trace->seq, "%9llu ",
361 data->hist[cpu].irq_count);
362
363 if (!params->common.hist.no_thread)
364 trace_seq_printf(trace->seq, "%9llu ",
365 data->hist[cpu].thread_count);
366
367 if (params->common.user_data)
368 trace_seq_printf(trace->seq, "%9llu ",
369 data->hist[cpu].user_count);
370 }
371 trace_seq_printf(trace->seq, "\n");
372
373 if (!params->common.hist.no_index)
374 trace_seq_printf(trace->seq, "min: ");
375
376 for_each_monitored_cpu(cpu, &params->common) {
377
378 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
379 continue;
380
381 if (!params->common.hist.no_irq)
382 format_summary_value(trace->seq,
383 data->hist[cpu].irq_count,
384 data->hist[cpu].min_irq,
385 false);
386
387 if (!params->common.hist.no_thread)
388 format_summary_value(trace->seq,
389 data->hist[cpu].thread_count,
390 data->hist[cpu].min_thread,
391 false);
392
393 if (params->common.user_data)
394 format_summary_value(trace->seq,
395 data->hist[cpu].user_count,
396 data->hist[cpu].min_user,
397 false);
398 }
399 trace_seq_printf(trace->seq, "\n");
400
401 if (!params->common.hist.no_index)
402 trace_seq_printf(trace->seq, "avg: ");
403
404 for_each_monitored_cpu(cpu, &params->common) {
405
406 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
407 continue;
408
409 if (!params->common.hist.no_irq)
410 format_summary_value(trace->seq,
411 data->hist[cpu].irq_count,
412 data->hist[cpu].sum_irq,
413 true);
414
415 if (!params->common.hist.no_thread)
416 format_summary_value(trace->seq,
417 data->hist[cpu].thread_count,
418 data->hist[cpu].sum_thread,
419 true);
420
421 if (params->common.user_data)
422 format_summary_value(trace->seq,
423 data->hist[cpu].user_count,
424 data->hist[cpu].sum_user,
425 true);
426 }
427 trace_seq_printf(trace->seq, "\n");
428
429 if (!params->common.hist.no_index)
430 trace_seq_printf(trace->seq, "max: ");
431
432 for_each_monitored_cpu(cpu, &params->common) {
433
434 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
435 continue;
436
437 if (!params->common.hist.no_irq)
438 format_summary_value(trace->seq,
439 data->hist[cpu].irq_count,
440 data->hist[cpu].max_irq,
441 false);
442
443 if (!params->common.hist.no_thread)
444 format_summary_value(trace->seq,
445 data->hist[cpu].thread_count,
446 data->hist[cpu].max_thread,
447 false);
448
449 if (params->common.user_data)
450 format_summary_value(trace->seq,
451 data->hist[cpu].user_count,
452 data->hist[cpu].max_user,
453 false);
454 }
455 trace_seq_printf(trace->seq, "\n");
456 trace_seq_do_printf(trace->seq);
457 trace_seq_reset(trace->seq);
458}
459
460static void
461timerlat_print_stats_all(struct timerlat_params *params,
462 struct trace_instance *trace,
463 struct timerlat_hist_data *data)
464{
465 struct timerlat_hist_cpu *cpu_data;
466 struct timerlat_hist_cpu sum;
467 int cpu;
468
469 if (params->common.hist.no_summary)
470 return;
471
472 memset(&sum, 0, sizeof(sum));
473 sum.min_irq = ~0;
474 sum.min_thread = ~0;
475 sum.min_user = ~0;
476
477 for_each_monitored_cpu(cpu, &params->common) {
478
479 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
480 continue;
481
482 cpu_data = &data->hist[cpu];
483
484 sum.irq_count += cpu_data->irq_count;
485 update_min(&sum.min_irq, &cpu_data->min_irq);
486 update_sum(&sum.sum_irq, &cpu_data->sum_irq);
487 update_max(&sum.max_irq, &cpu_data->max_irq);
488
489 sum.thread_count += cpu_data->thread_count;
490 update_min(&sum.min_thread, &cpu_data->min_thread);
491 update_sum(&sum.sum_thread, &cpu_data->sum_thread);
492 update_max(&sum.max_thread, &cpu_data->max_thread);
493
494 sum.user_count += cpu_data->user_count;
495 update_min(&sum.min_user, &cpu_data->min_user);
496 update_sum(&sum.sum_user, &cpu_data->sum_user);
497 update_max(&sum.max_user, &cpu_data->max_user);
498 }
499
500 if (!params->common.hist.no_index)
501 trace_seq_printf(trace->seq, "ALL: ");
502
503 if (!params->common.hist.no_irq)
504 trace_seq_printf(trace->seq, " IRQ");
505
506 if (!params->common.hist.no_thread)
507 trace_seq_printf(trace->seq, " Thr");
508
509 if (params->common.user_data)
510 trace_seq_printf(trace->seq, " Usr");
511
512 trace_seq_printf(trace->seq, "\n");
513
514 if (!params->common.hist.no_index)
515 trace_seq_printf(trace->seq, "count:");
516
517 if (!params->common.hist.no_irq)
518 trace_seq_printf(trace->seq, "%9llu ",
519 sum.irq_count);
520
521 if (!params->common.hist.no_thread)
522 trace_seq_printf(trace->seq, "%9llu ",
523 sum.thread_count);
524
525 if (params->common.user_data)
526 trace_seq_printf(trace->seq, "%9llu ",
527 sum.user_count);
528
529 trace_seq_printf(trace->seq, "\n");
530
531 if (!params->common.hist.no_index)
532 trace_seq_printf(trace->seq, "min: ");
533
534 if (!params->common.hist.no_irq)
535 format_summary_value(trace->seq,
536 sum.irq_count,
537 sum.min_irq,
538 false);
539
540 if (!params->common.hist.no_thread)
541 format_summary_value(trace->seq,
542 sum.thread_count,
543 sum.min_thread,
544 false);
545
546 if (params->common.user_data)
547 format_summary_value(trace->seq,
548 sum.user_count,
549 sum.min_user,
550 false);
551
552 trace_seq_printf(trace->seq, "\n");
553
554 if (!params->common.hist.no_index)
555 trace_seq_printf(trace->seq, "avg: ");
556
557 if (!params->common.hist.no_irq)
558 format_summary_value(trace->seq,
559 sum.irq_count,
560 sum.sum_irq,
561 true);
562
563 if (!params->common.hist.no_thread)
564 format_summary_value(trace->seq,
565 sum.thread_count,
566 sum.sum_thread,
567 true);
568
569 if (params->common.user_data)
570 format_summary_value(trace->seq,
571 sum.user_count,
572 sum.sum_user,
573 true);
574
575 trace_seq_printf(trace->seq, "\n");
576
577 if (!params->common.hist.no_index)
578 trace_seq_printf(trace->seq, "max: ");
579
580 if (!params->common.hist.no_irq)
581 format_summary_value(trace->seq,
582 sum.irq_count,
583 sum.max_irq,
584 false);
585
586 if (!params->common.hist.no_thread)
587 format_summary_value(trace->seq,
588 sum.thread_count,
589 sum.max_thread,
590 false);
591
592 if (params->common.user_data)
593 format_summary_value(trace->seq,
594 sum.user_count,
595 sum.max_user,
596 false);
597
598 trace_seq_printf(trace->seq, "\n");
599 trace_seq_do_printf(trace->seq);
600 trace_seq_reset(trace->seq);
601}
602
603/*
604 * timerlat_print_stats - print data for each CPUs
605 */
606static void
607timerlat_print_stats(struct osnoise_tool *tool)
608{
609 struct timerlat_params *params = to_timerlat_params(tool->params);
610 struct timerlat_hist_data *data = tool->data;
611 struct trace_instance *trace = &tool->trace;
612 int bucket, cpu;
613 int total;
614
615 timerlat_hist_header(tool);
616
617 for (bucket = 0; bucket < data->entries; bucket++) {
618 total = 0;
619
620 if (!params->common.hist.no_index)
621 trace_seq_printf(trace->seq, "%-6d",
622 bucket * data->bucket_size);
623
624 for_each_monitored_cpu(cpu, &params->common) {
625
626 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
627 continue;
628
629 if (!params->common.hist.no_irq) {
630 total += data->hist[cpu].irq[bucket];
631 trace_seq_printf(trace->seq, "%9d ",
632 data->hist[cpu].irq[bucket]);
633 }
634
635 if (!params->common.hist.no_thread) {
636 total += data->hist[cpu].thread[bucket];
637 trace_seq_printf(trace->seq, "%9d ",
638 data->hist[cpu].thread[bucket]);
639 }
640
641 if (params->common.user_data) {
642 total += data->hist[cpu].user[bucket];
643 trace_seq_printf(trace->seq, "%9d ",
644 data->hist[cpu].user[bucket]);
645 }
646
647 }
648
649 if (total == 0 && !params->common.hist.with_zeros) {
650 trace_seq_reset(trace->seq);
651 continue;
652 }
653
654 trace_seq_printf(trace->seq, "\n");
655 trace_seq_do_printf(trace->seq);
656 trace_seq_reset(trace->seq);
657 }
658
659 if (!params->common.hist.no_index)
660 trace_seq_printf(trace->seq, "over: ");
661
662 for_each_monitored_cpu(cpu, &params->common) {
663
664 if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
665 continue;
666
667 if (!params->common.hist.no_irq)
668 trace_seq_printf(trace->seq, "%9d ",
669 data->hist[cpu].irq[data->entries]);
670
671 if (!params->common.hist.no_thread)
672 trace_seq_printf(trace->seq, "%9d ",
673 data->hist[cpu].thread[data->entries]);
674
675 if (params->common.user_data)
676 trace_seq_printf(trace->seq, "%9d ",
677 data->hist[cpu].user[data->entries]);
678 }
679 trace_seq_printf(trace->seq, "\n");
680 trace_seq_do_printf(trace->seq);
681 trace_seq_reset(trace->seq);
682
683 timerlat_print_summary(params, trace, data);
684 timerlat_print_stats_all(params, trace, data);
685 osnoise_report_missed_events(tool);
686}
687
688/*
689 * timerlat_hist_apply_config - apply the hist configs to the initialized tool
690 */
691static int
692timerlat_hist_apply_config(struct osnoise_tool *tool)
693{
694 struct timerlat_params *params = to_timerlat_params(tool->params);
695 int retval;
696
697 retval = timerlat_apply_config(tool, params);
698 if (retval)
699 goto out_err;
700
701 return 0;
702
703out_err:
704 return -1;
705}
706
707/*
708 * timerlat_init_hist - initialize a timerlat hist tool with parameters
709 */
710static struct osnoise_tool
711*timerlat_init_hist(struct common_params *params)
712{
713 struct osnoise_tool *tool;
714
715 tool = osnoise_init_tool("timerlat_hist");
716 if (!tool)
717 return NULL;
718
719 tool->data = timerlat_alloc_histogram(params->hist.entries,
720 params->hist.bucket_size);
721 if (!tool->data)
722 goto out_err;
723
724 tep_register_event_handler(tool->trace.tep, -1, "ftrace", "timerlat",
725 timerlat_hist_handler, tool);
726
727 return tool;
728
729out_err:
730 osnoise_destroy_tool(tool);
731 return NULL;
732}
733
734static int timerlat_hist_bpf_main_loop(struct osnoise_tool *tool)
735{
736 int retval;
737
738 while (!stop_tracing) {
739 timerlat_bpf_wait(-1);
740
741 if (!stop_tracing) {
742 /* Threshold overflow, perform actions on threshold */
743 retval = common_threshold_handler(tool);
744 if (retval)
745 return retval;
746
747 if (!should_continue_tracing(tool->params))
748 break;
749
750 if (timerlat_bpf_restart_tracing()) {
751 err_msg("Error restarting BPF trace\n");
752 return -1;
753 }
754 }
755 }
756 timerlat_bpf_detach();
757
758 retval = timerlat_hist_bpf_pull_data(tool);
759 if (retval)
760 err_msg("Error pulling BPF data\n");
761
762 return retval;
763}
764
765static int timerlat_hist_main(struct osnoise_tool *tool)
766{
767 struct timerlat_params *params = to_timerlat_params(tool->params);
768 int retval;
769
770 if (params->mode == TRACING_MODE_TRACEFS)
771 retval = hist_main_loop(tool);
772 else
773 retval = timerlat_hist_bpf_main_loop(tool);
774
775 return retval;
776}
777
778struct tool_ops timerlat_hist_ops = {
779 .tracer = "timerlat",
780 .comm_prefix = "timerlat/",
781 .parse_args = timerlat_hist_parse_args,
782 .init_tool = timerlat_init_hist,
783 .apply_config = timerlat_hist_apply_config,
784 .enable = timerlat_enable,
785 .main = timerlat_hist_main,
786 .print_stats = timerlat_print_stats,
787 .analyze = timerlat_analyze,
788 .free = timerlat_free_histogram_tool,
789};