1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2021 Red Hat Inc, Daniel Bristot de Oliveira <bristot@kernel.org>
4 */
5
6 #define _GNU_SOURCE
7 #include <getopt.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <signal.h>
11 #include <unistd.h>
12 #include <stdio.h>
13 #include <time.h>
14 #include <errno.h>
15 #include <sched.h>
16 #include <pthread.h>
17
18 #include "utils.h"
19 #include "osnoise.h"
20 #include "timerlat.h"
21 #include "timerlat_aa.h"
22 #include "timerlat_u.h"
23
24 struct timerlat_top_params {
25 char *cpus;
26 cpu_set_t monitored_cpus;
27 char *trace_output;
28 char *cgroup_name;
29 unsigned long long runtime;
30 long long stop_us;
31 long long stop_total_us;
32 long long timerlat_period_us;
33 long long print_stack;
34 int sleep_time;
35 int output_divisor;
36 int duration;
37 int quiet;
38 int set_sched;
39 int dma_latency;
40 int no_aa;
41 int aa_only;
42 int dump_tasks;
43 int cgroup;
44 int hk_cpus;
45 int user_top;
46 int user_workload;
47 int kernel_workload;
48 int pretty_output;
49 int warmup;
50 int buffer_size;
51 cpu_set_t hk_cpu_set;
52 struct sched_attr sched_param;
53 struct trace_events *events;
54 };
55
56 struct timerlat_top_cpu {
57 int irq_count;
58 int thread_count;
59 int user_count;
60
61 unsigned long long cur_irq;
62 unsigned long long min_irq;
63 unsigned long long sum_irq;
64 unsigned long long max_irq;
65
66 unsigned long long cur_thread;
67 unsigned long long min_thread;
68 unsigned long long sum_thread;
69 unsigned long long max_thread;
70
71 unsigned long long cur_user;
72 unsigned long long min_user;
73 unsigned long long sum_user;
74 unsigned long long max_user;
75 };
76
77 struct timerlat_top_data {
78 struct timerlat_top_cpu *cpu_data;
79 int nr_cpus;
80 };
81
82 /*
83 * timerlat_free_top - free runtime data
84 */
85 static void
86 timerlat_free_top(struct timerlat_top_data *data)
87 {
88 free(data->cpu_data);
89 free(data);
90 }
91
92 /*
93 * timerlat_alloc_histogram - alloc runtime data
94 */
95 static struct timerlat_top_data *timerlat_alloc_top(int nr_cpus)
96 {
97 struct timerlat_top_data *data;
98 int cpu;
99
100 data = calloc(1, sizeof(*data));
101 if (!data)
102 return NULL;
103
104 data->nr_cpus = nr_cpus;
105
106 /* one set of histograms per CPU */
107 data->cpu_data = calloc(1, sizeof(*data->cpu_data) * nr_cpus);
108 if (!data->cpu_data)
109 goto cleanup;
110
111 /* set the min to max */
112 for (cpu = 0; cpu < nr_cpus; cpu++) {
113 data->cpu_data[cpu].min_irq = ~0;
114 data->cpu_data[cpu].min_thread = ~0;
115 data->cpu_data[cpu].min_user = ~0;
116 }
117
118 return data;
119
120 cleanup:
121 timerlat_free_top(data);
122 return NULL;
123 }
124
125 static void
126 timerlat_top_reset_sum(struct timerlat_top_cpu *summary)
127 {
128 memset(summary, 0, sizeof(*summary));
129 summary->min_irq = ~0;
130 summary->min_thread = ~0;
131 summary->min_user = ~0;
132 }
133
134 static void
135 timerlat_top_update_sum(struct osnoise_tool *tool, int cpu, struct timerlat_top_cpu *sum)
136 {
137 struct timerlat_top_data *data = tool->data;
138 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
139
140 sum->irq_count += cpu_data->irq_count;
141 update_min(&sum->min_irq, &cpu_data->min_irq);
142 update_sum(&sum->sum_irq, &cpu_data->sum_irq);
143 update_max(&sum->max_irq, &cpu_data->max_irq);
144
145 sum->thread_count += cpu_data->thread_count;
146 update_min(&sum->min_thread, &cpu_data->min_thread);
147 update_sum(&sum->sum_thread, &cpu_data->sum_thread);
148 update_max(&sum->max_thread, &cpu_data->max_thread);
149
150 sum->user_count += cpu_data->user_count;
151 update_min(&sum->min_user, &cpu_data->min_user);
152 update_sum(&sum->sum_user, &cpu_data->sum_user);
153 update_max(&sum->max_user, &cpu_data->max_user);
154 }
155
156 /*
157 * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
158 */
159 static void
160 timerlat_top_update(struct osnoise_tool *tool, int cpu,
161 unsigned long long thread,
162 unsigned long long latency)
163 {
164 struct timerlat_top_data *data = tool->data;
165 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
166
167 if (!thread) {
168 cpu_data->irq_count++;
169 cpu_data->cur_irq = latency;
170 update_min(&cpu_data->min_irq, &latency);
171 update_sum(&cpu_data->sum_irq, &latency);
172 update_max(&cpu_data->max_irq, &latency);
173 } else if (thread == 1) {
174 cpu_data->thread_count++;
175 cpu_data->cur_thread = latency;
176 update_min(&cpu_data->min_thread, &latency);
177 update_sum(&cpu_data->sum_thread, &latency);
178 update_max(&cpu_data->max_thread, &latency);
179 } else {
180 cpu_data->user_count++;
181 cpu_data->cur_user = latency;
182 update_min(&cpu_data->min_user, &latency);
183 update_sum(&cpu_data->sum_user, &latency);
184 update_max(&cpu_data->max_user, &latency);
185 }
186 }
187
188 /*
189 * timerlat_top_handler - this is the handler for timerlat tracer events
190 */
191 static int
192 timerlat_top_handler(struct trace_seq *s, struct tep_record *record,
193 struct tep_event *event, void *context)
194 {
195 struct trace_instance *trace = context;
196 struct timerlat_top_params *params;
197 unsigned long long latency, thread;
198 struct osnoise_tool *top;
199 int cpu = record->cpu;
200
201 top = container_of(trace, struct osnoise_tool, trace);
202 params = top->params;
203
204 if (!params->aa_only) {
205 tep_get_field_val(s, event, "context", record, &thread, 1);
206 tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
207
208 timerlat_top_update(top, cpu, thread, latency);
209 }
210
211 return 0;
212 }
213
214 /*
215 * timerlat_top_header - print the header of the tool output
216 */
217 static void timerlat_top_header(struct timerlat_top_params *params, struct osnoise_tool *top)
218 {
219 struct trace_seq *s = top->trace.seq;
220 char duration[26];
221
222 get_duration(top->start_time, duration, sizeof(duration));
223
224 if (params->pretty_output)
225 trace_seq_printf(s, "\033[2;37;40m");
226
227 trace_seq_printf(s, " Timer Latency ");
228 if (params->user_top)
229 trace_seq_printf(s, " ");
230
231 if (params->pretty_output)
232 trace_seq_printf(s, "\033[0;0;0m");
233 trace_seq_printf(s, "\n");
234
235 trace_seq_printf(s, "%-6s | IRQ Timer Latency (%s) | Thread Timer Latency (%s)", duration,
236 params->output_divisor == 1 ? "ns" : "us",
237 params->output_divisor == 1 ? "ns" : "us");
238
239 if (params->user_top) {
240 trace_seq_printf(s, " | Ret user Timer Latency (%s)",
241 params->output_divisor == 1 ? "ns" : "us");
242 }
243
244 trace_seq_printf(s, "\n");
245 if (params->pretty_output)
246 trace_seq_printf(s, "\033[2;30;47m");
247
248 trace_seq_printf(s, "CPU COUNT | cur min avg max | cur min avg max");
249 if (params->user_top)
250 trace_seq_printf(s, " | cur min avg max");
251
252 if (params->pretty_output)
253 trace_seq_printf(s, "\033[0;0;0m");
254 trace_seq_printf(s, "\n");
255 }
256
257 static const char *no_value = " -";
258
259 /*
260 * timerlat_top_print - prints the output of a given CPU
261 */
262 static void timerlat_top_print(struct osnoise_tool *top, int cpu)
263 {
264
265 struct timerlat_top_params *params = top->params;
266 struct timerlat_top_data *data = top->data;
267 struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
268 int divisor = params->output_divisor;
269 struct trace_seq *s = top->trace.seq;
270
271 if (divisor == 0)
272 return;
273
274 /*
275 * Skip if no data is available: is this cpu offline?
276 */
277 if (!cpu_data->irq_count && !cpu_data->thread_count)
278 return;
279
280 /*
281 * Unless trace is being lost, IRQ counter is always the max.
282 */
283 trace_seq_printf(s, "%3d #%-9d |", cpu, cpu_data->irq_count);
284
285 if (!cpu_data->irq_count) {
286 trace_seq_printf(s, "%s %s %s %s |", no_value, no_value, no_value, no_value);
287 } else {
288 trace_seq_printf(s, "%9llu ", cpu_data->cur_irq / params->output_divisor);
289 trace_seq_printf(s, "%9llu ", cpu_data->min_irq / params->output_divisor);
290 trace_seq_printf(s, "%9llu ", (cpu_data->sum_irq / cpu_data->irq_count) / divisor);
291 trace_seq_printf(s, "%9llu |", cpu_data->max_irq / divisor);
292 }
293
294 if (!cpu_data->thread_count) {
295 trace_seq_printf(s, "%s %s %s %s", no_value, no_value, no_value, no_value);
296 } else {
297 trace_seq_printf(s, "%9llu ", cpu_data->cur_thread / divisor);
298 trace_seq_printf(s, "%9llu ", cpu_data->min_thread / divisor);
299 trace_seq_printf(s, "%9llu ",
300 (cpu_data->sum_thread / cpu_data->thread_count) / divisor);
301 trace_seq_printf(s, "%9llu", cpu_data->max_thread / divisor);
302 }
303
304 if (!params->user_top) {
305 trace_seq_printf(s, "\n");
306 return;
307 }
308
309 trace_seq_printf(s, " |");
310
311 if (!cpu_data->user_count) {
312 trace_seq_printf(s, "%s %s %s %s\n", no_value, no_value, no_value, no_value);
313 } else {
314 trace_seq_printf(s, "%9llu ", cpu_data->cur_user / divisor);
315 trace_seq_printf(s, "%9llu ", cpu_data->min_user / divisor);
316 trace_seq_printf(s, "%9llu ",
317 (cpu_data->sum_user / cpu_data->user_count) / divisor);
318 trace_seq_printf(s, "%9llu\n", cpu_data->max_user / divisor);
319 }
320 }
321
322 /*
323 * timerlat_top_print_sum - prints the summary output
324 */
325 static void
326 timerlat_top_print_sum(struct osnoise_tool *top, struct timerlat_top_cpu *summary)
327 {
328 const char *split = "----------------------------------------";
329 struct timerlat_top_params *params = top->params;
330 unsigned long long count = summary->irq_count;
331 int divisor = params->output_divisor;
332 struct trace_seq *s = top->trace.seq;
333 int e = 0;
334
335 if (divisor == 0)
336 return;
337
338 /*
339 * Skip if no data is available: is this cpu offline?
340 */
341 if (!summary->irq_count && !summary->thread_count)
342 return;
343
344 while (count > 999999) {
345 e++;
346 count /= 10;
347 }
348
349 trace_seq_printf(s, "%.*s|%.*s|%.*s", 15, split, 40, split, 39, split);
350 if (params->user_top)
351 trace_seq_printf(s, "-|%.*s", 39, split);
352 trace_seq_printf(s, "\n");
353
354 trace_seq_printf(s, "ALL #%-6llu e%d |", count, e);
355
356 if (!summary->irq_count) {
357 trace_seq_printf(s, " %s %s %s |", no_value, no_value, no_value);
358 } else {
359 trace_seq_printf(s, " ");
360 trace_seq_printf(s, "%9llu ", summary->min_irq / params->output_divisor);
361 trace_seq_printf(s, "%9llu ", (summary->sum_irq / summary->irq_count) / divisor);
362 trace_seq_printf(s, "%9llu |", summary->max_irq / divisor);
363 }
364
365 if (!summary->thread_count) {
366 trace_seq_printf(s, "%s %s %s %s", no_value, no_value, no_value, no_value);
367 } else {
368 trace_seq_printf(s, " ");
369 trace_seq_printf(s, "%9llu ", summary->min_thread / divisor);
370 trace_seq_printf(s, "%9llu ",
371 (summary->sum_thread / summary->thread_count) / divisor);
372 trace_seq_printf(s, "%9llu", summary->max_thread / divisor);
373 }
374
375 if (!params->user_top) {
376 trace_seq_printf(s, "\n");
377 return;
378 }
379
380 trace_seq_printf(s, " |");
381
382 if (!summary->user_count) {
383 trace_seq_printf(s, " %s %s %s |", no_value, no_value, no_value);
384 } else {
385 trace_seq_printf(s, " ");
386 trace_seq_printf(s, "%9llu ", summary->min_user / divisor);
387 trace_seq_printf(s, "%9llu ",
388 (summary->sum_user / summary->user_count) / divisor);
389 trace_seq_printf(s, "%9llu\n", summary->max_user / divisor);
390 }
391 }
392
393 /*
394 * clear_terminal - clears the output terminal
395 */
396 static void clear_terminal(struct trace_seq *seq)
397 {
398 if (!config_debug)
399 trace_seq_printf(seq, "\033c");
400 }
401
402 /*
403 * timerlat_print_stats - print data for all cpus
404 */
405 static void
406 timerlat_print_stats(struct timerlat_top_params *params, struct osnoise_tool *top)
407 {
408 struct trace_instance *trace = &top->trace;
409 struct timerlat_top_cpu summary;
410 static int nr_cpus = -1;
411 int i;
412
413 if (params->aa_only)
414 return;
415
416 if (nr_cpus == -1)
417 nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
418
419 if (!params->quiet)
420 clear_terminal(trace->seq);
421
422 timerlat_top_reset_sum(&summary);
423
424 timerlat_top_header(params, top);
425
426 for (i = 0; i < nr_cpus; i++) {
427 if (params->cpus && !CPU_ISSET(i, ¶ms->monitored_cpus))
428 continue;
429 timerlat_top_print(top, i);
430 timerlat_top_update_sum(top, i, &summary);
431 }
432
433 timerlat_top_print_sum(top, &summary);
434
435 trace_seq_do_printf(trace->seq);
436 trace_seq_reset(trace->seq);
437 }
438
439 /*
440 * timerlat_top_usage - prints timerlat top usage message
441 */
442 static void timerlat_top_usage(char *usage)
443 {
444 int i;
445
446 static const char *const msg[] = {
447 "",
448 " usage: rtla timerlat [top] [-h] [-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\",
449 " [[-t[file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
450 " [-P priority] [--dma-latency us] [--aa-only us] [-C[=cgroup_name]] [-u|-k] [--warm-up s]",
451 "",
452 " -h/--help: print this menu",
453 " -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
454 " --aa-only us: stop if <us> latency is hit, only printing the auto analysis (reduces CPU usage)",
455 " -p/--period us: timerlat period in us",
456 " -i/--irq us: stop trace if the irq latency is higher than the argument in us",
457 " -T/--thread us: stop trace if the thread latency is higher than the argument in us",
458 " -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
459 " -c/--cpus cpus: run the tracer only on the given cpus",
460 " -H/--house-keeping cpus: run rtla control threads only on the given cpus",
461 " -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
462 " -d/--duration time[s|m|h|d]: duration of the session",
463 " -D/--debug: print debug info",
464 " --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)",
465 " -t/--trace[file]: save the stopped trace to [file|timerlat_trace.txt]",
466 " -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
467 " --filter <command>: enable a trace event filter to the previous -e event",
468 " --trigger <command>: enable a trace event trigger to the previous -e event",
469 " -n/--nano: display data in nanoseconds",
470 " --no-aa: disable auto-analysis, reducing rtla timerlat cpu usage",
471 " -q/--quiet print only a summary at the end",
472 " --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency",
473 " -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
474 " o:prio - use SCHED_OTHER with prio",
475 " r:prio - use SCHED_RR with prio",
476 " f:prio - use SCHED_FIFO with prio",
477 " d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period",
478 " in nanoseconds",
479 " -u/--user-threads: use rtla user-space threads instead of kernel-space timerlat threads",
480 " -k/--kernel-threads: use timerlat kernel-space threads instead of rtla user-space threads",
481 " -U/--user-load: enable timerlat for user-defined user-space workload",
482 " --warm-up s: let the workload run for s seconds before collecting data",
483 " --trace-buffer-size kB: set the per-cpu trace buffer size in kB",
484 NULL,
485 };
486
487 if (usage)
488 fprintf(stderr, "%s\n", usage);
489
490 fprintf(stderr, "rtla timerlat top: a per-cpu summary of the timer latency (version %s)\n",
491 VERSION);
492
493 for (i = 0; msg[i]; i++)
494 fprintf(stderr, "%s\n", msg[i]);
495
496 if (usage)
497 exit(EXIT_FAILURE);
498
499 exit(EXIT_SUCCESS);
500 }
501
502 /*
503 * timerlat_top_parse_args - allocs, parse and fill the cmd line parameters
504 */
505 static struct timerlat_top_params
506 *timerlat_top_parse_args(int argc, char **argv)
507 {
508 struct timerlat_top_params *params;
509 struct trace_events *tevent;
510 long long auto_thresh;
511 int retval;
512 int c;
513
514 params = calloc(1, sizeof(*params));
515 if (!params)
516 exit(1);
517
518 /* disabled by default */
519 params->dma_latency = -1;
520
521 /* display data in microseconds */
522 params->output_divisor = 1000;
523
524 while (1) {
525 static struct option long_options[] = {
526 {"auto", required_argument, 0, 'a'},
527 {"cpus", required_argument, 0, 'c'},
528 {"cgroup", optional_argument, 0, 'C'},
529 {"debug", no_argument, 0, 'D'},
530 {"duration", required_argument, 0, 'd'},
531 {"event", required_argument, 0, 'e'},
532 {"help", no_argument, 0, 'h'},
533 {"house-keeping", required_argument, 0, 'H'},
534 {"irq", required_argument, 0, 'i'},
535 {"nano", no_argument, 0, 'n'},
536 {"period", required_argument, 0, 'p'},
537 {"priority", required_argument, 0, 'P'},
538 {"quiet", no_argument, 0, 'q'},
539 {"stack", required_argument, 0, 's'},
540 {"thread", required_argument, 0, 'T'},
541 {"trace", optional_argument, 0, 't'},
542 {"user-threads", no_argument, 0, 'u'},
543 {"kernel-threads", no_argument, 0, 'k'},
544 {"user-load", no_argument, 0, 'U'},
545 {"trigger", required_argument, 0, ''},
546 {"filter", required_argument, 0, '1'},
547 {"dma-latency", required_argument, 0, '2'},
548 {"no-aa", no_argument, 0, '3'},
549 {"dump-tasks", no_argument, 0, '4'},
550 {"aa-only", required_argument, 0, '5'},
551 {"warm-up", required_argument, 0, '6'},
552 {"trace-buffer-size", required_argument, 0, '7'},
553 {0, 0, 0, 0}
554 };
555
556 /* getopt_long stores the option index here. */
557 int option_index = 0;
558
559 c = getopt_long(argc, argv, "a:c:C::d:De:hH:i:knp:P:qs:t::T:uU0:1:2:345:6:7:",
560 long_options, &option_index);
561
562 /* detect the end of the options. */
563 if (c == -1)
564 break;
565
566 switch (c) {
567 case 'a':
568 auto_thresh = get_llong_from_str(optarg);
569
570 /* set thread stop to auto_thresh */
571 params->stop_total_us = auto_thresh;
572 params->stop_us = auto_thresh;
573
574 /* get stack trace */
575 params->print_stack = auto_thresh;
576
577 /* set trace */
578 params->trace_output = "timerlat_trace.txt";
579 break;
580 case '5':
581 /* it is here because it is similar to -a */
582 auto_thresh = get_llong_from_str(optarg);
583
584 /* set thread stop to auto_thresh */
585 params->stop_total_us = auto_thresh;
586 params->stop_us = auto_thresh;
587
588 /* get stack trace */
589 params->print_stack = auto_thresh;
590
591 /* set aa_only to avoid parsing the trace */
592 params->aa_only = 1;
593 break;
594 case 'c':
595 retval = parse_cpu_set(optarg, ¶ms->monitored_cpus);
596 if (retval)
597 timerlat_top_usage("\nInvalid -c cpu list\n");
598 params->cpus = optarg;
599 break;
600 case 'C':
601 params->cgroup = 1;
602 if (!optarg) {
603 /* will inherit this cgroup */
604 params->cgroup_name = NULL;
605 } else if (*optarg == '=') {
606 /* skip the = */
607 params->cgroup_name = ++optarg;
608 }
609 break;
610 case 'D':
611 config_debug = 1;
612 break;
613 case 'd':
614 params->duration = parse_seconds_duration(optarg);
615 if (!params->duration)
616 timerlat_top_usage("Invalid -d duration\n");
617 break;
618 case 'e':
619 tevent = trace_event_alloc(optarg);
620 if (!tevent) {
621 err_msg("Error alloc trace event");
622 exit(EXIT_FAILURE);
623 }
624
625 if (params->events)
626 tevent->next = params->events;
627 params->events = tevent;
628 break;
629 case 'h':
630 case '?':
631 timerlat_top_usage(NULL);
632 break;
633 case 'H':
634 params->hk_cpus = 1;
635 retval = parse_cpu_set(optarg, ¶ms->hk_cpu_set);
636 if (retval) {
637 err_msg("Error parsing house keeping CPUs\n");
638 exit(EXIT_FAILURE);
639 }
640 break;
641 case 'i':
642 params->stop_us = get_llong_from_str(optarg);
643 break;
644 case 'k':
645 params->kernel_workload = true;
646 break;
647 case 'n':
648 params->output_divisor = 1;
649 break;
650 case 'p':
651 params->timerlat_period_us = get_llong_from_str(optarg);
652 if (params->timerlat_period_us > 1000000)
653 timerlat_top_usage("Period longer than 1 s\n");
654 break;
655 case 'P':
656 retval = parse_prio(optarg, ¶ms->sched_param);
657 if (retval == -1)
658 timerlat_top_usage("Invalid -P priority");
659 params->set_sched = 1;
660 break;
661 case 'q':
662 params->quiet = 1;
663 break;
664 case 's':
665 params->print_stack = get_llong_from_str(optarg);
666 break;
667 case 'T':
668 params->stop_total_us = get_llong_from_str(optarg);
669 break;
670 case 't':
671 if (optarg) {
672 if (optarg[0] == '=')
673 params->trace_output = &optarg[1];
674 else
675 params->trace_output = &optarg[0];
676 } else if (optind < argc && argv[optind][0] != '-')
677 params->trace_output = argv[optind];
678 else
679 params->trace_output = "timerlat_trace.txt";
680
681 break;
682 case 'u':
683 params->user_workload = true;
684 /* fallback: -u implies -U */
685 case 'U':
686 params->user_top = true;
687 break;
688 case '': /* trigger */
689 if (params->events) {
690 retval = trace_event_add_trigger(params->events, optarg);
691 if (retval) {
692 err_msg("Error adding trigger %s\n", optarg);
693 exit(EXIT_FAILURE);
694 }
695 } else {
696 timerlat_top_usage("--trigger requires a previous -e\n");
697 }
698 break;
699 case '1': /* filter */
700 if (params->events) {
701 retval = trace_event_add_filter(params->events, optarg);
702 if (retval) {
703 err_msg("Error adding filter %s\n", optarg);
704 exit(EXIT_FAILURE);
705 }
706 } else {
707 timerlat_top_usage("--filter requires a previous -e\n");
708 }
709 break;
710 case '2': /* dma-latency */
711 params->dma_latency = get_llong_from_str(optarg);
712 if (params->dma_latency < 0 || params->dma_latency > 10000) {
713 err_msg("--dma-latency needs to be >= 0 and < 10000");
714 exit(EXIT_FAILURE);
715 }
716 break;
717 case '3': /* no-aa */
718 params->no_aa = 1;
719 break;
720 case '4':
721 params->dump_tasks = 1;
722 break;
723 case '6':
724 params->warmup = get_llong_from_str(optarg);
725 break;
726 case '7':
727 params->buffer_size = get_llong_from_str(optarg);
728 break;
729 default:
730 timerlat_top_usage("Invalid option");
731 }
732 }
733
734 if (geteuid()) {
735 err_msg("rtla needs root permission\n");
736 exit(EXIT_FAILURE);
737 }
738
739 /*
740 * Auto analysis only happens if stop tracing, thus:
741 */
742 if (!params->stop_us && !params->stop_total_us)
743 params->no_aa = 1;
744
745 if (params->no_aa && params->aa_only)
746 timerlat_top_usage("--no-aa and --aa-only are mutually exclusive!");
747
748 if (params->kernel_workload && params->user_workload)
749 timerlat_top_usage("--kernel-threads and --user-threads are mutually exclusive!");
750
751 return params;
752 }
753
754 /*
755 * timerlat_top_apply_config - apply the top configs to the initialized tool
756 */
757 static int
758 timerlat_top_apply_config(struct osnoise_tool *top, struct timerlat_top_params *params)
759 {
760 int retval;
761 int i;
762
763 if (!params->sleep_time)
764 params->sleep_time = 1;
765
766 if (params->cpus) {
767 retval = osnoise_set_cpus(top->context, params->cpus);
768 if (retval) {
769 err_msg("Failed to apply CPUs config\n");
770 goto out_err;
771 }
772 } else {
773 for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++)
774 CPU_SET(i, ¶ms->monitored_cpus);
775 }
776
777 if (params->stop_us) {
778 retval = osnoise_set_stop_us(top->context, params->stop_us);
779 if (retval) {
780 err_msg("Failed to set stop us\n");
781 goto out_err;
782 }
783 }
784
785 if (params->stop_total_us) {
786 retval = osnoise_set_stop_total_us(top->context, params->stop_total_us);
787 if (retval) {
788 err_msg("Failed to set stop total us\n");
789 goto out_err;
790 }
791 }
792
793
794 if (params->timerlat_period_us) {
795 retval = osnoise_set_timerlat_period_us(top->context, params->timerlat_period_us);
796 if (retval) {
797 err_msg("Failed to set timerlat period\n");
798 goto out_err;
799 }
800 }
801
802
803 if (params->print_stack) {
804 retval = osnoise_set_print_stack(top->context, params->print_stack);
805 if (retval) {
806 err_msg("Failed to set print stack\n");
807 goto out_err;
808 }
809 }
810
811 if (params->hk_cpus) {
812 retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set),
813 ¶ms->hk_cpu_set);
814 if (retval == -1) {
815 err_msg("Failed to set rtla to the house keeping CPUs\n");
816 goto out_err;
817 }
818 } else if (params->cpus) {
819 /*
820 * Even if the user do not set a house-keeping CPU, try to
821 * move rtla to a CPU set different to the one where the user
822 * set the workload to run.
823 *
824 * No need to check results as this is an automatic attempt.
825 */
826 auto_house_keeping(¶ms->monitored_cpus);
827 }
828
829 /*
830 * If the user did not specify a type of thread, try user-threads first.
831 * Fall back to kernel threads otherwise.
832 */
833 if (!params->kernel_workload && !params->user_workload) {
834 retval = tracefs_file_exists(NULL, "osnoise/per_cpu/cpu0/timerlat_fd");
835 if (retval) {
836 debug_msg("User-space interface detected, setting user-threads\n");
837 params->user_workload = 1;
838 params->user_top = 1;
839 } else {
840 debug_msg("User-space interface not detected, setting kernel-threads\n");
841 params->kernel_workload = 1;
842 }
843 }
844
845 if (params->user_top) {
846 retval = osnoise_set_workload(top->context, 0);
847 if (retval) {
848 err_msg("Failed to set OSNOISE_WORKLOAD option\n");
849 goto out_err;
850 }
851 }
852
853 if (isatty(1) && !params->quiet)
854 params->pretty_output = 1;
855
856 return 0;
857
858 out_err:
859 return -1;
860 }
861
862 /*
863 * timerlat_init_top - initialize a timerlat top tool with parameters
864 */
865 static struct osnoise_tool
866 *timerlat_init_top(struct timerlat_top_params *params)
867 {
868 struct osnoise_tool *top;
869 int nr_cpus;
870
871 nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
872
873 top = osnoise_init_tool("timerlat_top");
874 if (!top)
875 return NULL;
876
877 top->data = timerlat_alloc_top(nr_cpus);
878 if (!top->data)
879 goto out_err;
880
881 top->params = params;
882
883 tep_register_event_handler(top->trace.tep, -1, "ftrace", "timerlat",
884 timerlat_top_handler, top);
885
886 return top;
887
888 out_err:
889 osnoise_destroy_tool(top);
890 return NULL;
891 }
892
893 static int stop_tracing;
894 static void stop_top(int sig)
895 {
896 stop_tracing = 1;
897 }
898
899 /*
900 * timerlat_top_set_signals - handles the signal to stop the tool
901 */
902 static void
903 timerlat_top_set_signals(struct timerlat_top_params *params)
904 {
905 signal(SIGINT, stop_top);
906 if (params->duration) {
907 signal(SIGALRM, stop_top);
908 alarm(params->duration);
909 }
910 }
911
912 int timerlat_top_main(int argc, char *argv[])
913 {
914 struct timerlat_top_params *params;
915 struct osnoise_tool *record = NULL;
916 struct timerlat_u_params params_u;
917 struct osnoise_tool *top = NULL;
918 struct osnoise_tool *aa = NULL;
919 struct trace_instance *trace;
920 int dma_latency_fd = -1;
921 pthread_t timerlat_u;
922 int return_value = 1;
923 char *max_lat;
924 int retval;
925
926 params = timerlat_top_parse_args(argc, argv);
927 if (!params)
928 exit(1);
929
930 top = timerlat_init_top(params);
931 if (!top) {
932 err_msg("Could not init osnoise top\n");
933 goto out_exit;
934 }
935
936 retval = timerlat_top_apply_config(top, params);
937 if (retval) {
938 err_msg("Could not apply config\n");
939 goto out_free;
940 }
941
942 trace = &top->trace;
943
944 retval = enable_timerlat(trace);
945 if (retval) {
946 err_msg("Failed to enable timerlat tracer\n");
947 goto out_free;
948 }
949
950 if (params->set_sched) {
951 retval = set_comm_sched_attr("timerlat/", ¶ms->sched_param);
952 if (retval) {
953 err_msg("Failed to set sched parameters\n");
954 goto out_free;
955 }
956 }
957
958 if (params->cgroup && !params->user_top) {
959 retval = set_comm_cgroup("timerlat/", params->cgroup_name);
960 if (!retval) {
961 err_msg("Failed to move threads to cgroup\n");
962 goto out_free;
963 }
964 }
965
966 if (params->dma_latency >= 0) {
967 dma_latency_fd = set_cpu_dma_latency(params->dma_latency);
968 if (dma_latency_fd < 0) {
969 err_msg("Could not set /dev/cpu_dma_latency.\n");
970 goto out_free;
971 }
972 }
973
974 if (params->trace_output) {
975 record = osnoise_init_trace_tool("timerlat");
976 if (!record) {
977 err_msg("Failed to enable the trace instance\n");
978 goto out_free;
979 }
980
981 if (params->events) {
982 retval = trace_events_enable(&record->trace, params->events);
983 if (retval)
984 goto out_top;
985 }
986
987 if (params->buffer_size > 0) {
988 retval = trace_set_buffer_size(&record->trace, params->buffer_size);
989 if (retval)
990 goto out_top;
991 }
992 }
993
994 if (!params->no_aa) {
995 if (params->aa_only) {
996 /* as top is not used for display, use it for aa */
997 aa = top;
998 } else {
999 /* otherwise, a new instance is needed */
1000 aa = osnoise_init_tool("timerlat_aa");
1001 if (!aa)
1002 goto out_top;
1003 }
1004
1005 retval = timerlat_aa_init(aa, params->dump_tasks);
1006 if (retval) {
1007 err_msg("Failed to enable the auto analysis instance\n");
1008 goto out_top;
1009 }
1010
1011 /* if it is re-using the main instance, there is no need to start it */
1012 if (aa != top) {
1013 retval = enable_timerlat(&aa->trace);
1014 if (retval) {
1015 err_msg("Failed to enable timerlat tracer\n");
1016 goto out_top;
1017 }
1018 }
1019 }
1020
1021 if (params->user_workload) {
1022 /* rtla asked to stop */
1023 params_u.should_run = 1;
1024 /* all threads left */
1025 params_u.stopped_running = 0;
1026
1027 params_u.set = ¶ms->monitored_cpus;
1028 if (params->set_sched)
1029 params_u.sched_param = ¶ms->sched_param;
1030 else
1031 params_u.sched_param = NULL;
1032
1033 params_u.cgroup_name = params->cgroup_name;
1034
1035 retval = pthread_create(&timerlat_u, NULL, timerlat_u_dispatcher, ¶ms_u);
1036 if (retval)
1037 err_msg("Error creating timerlat user-space threads\n");
1038 }
1039
1040 if (params->warmup > 0) {
1041 debug_msg("Warming up for %d seconds\n", params->warmup);
1042 sleep(params->warmup);
1043 }
1044
1045 /*
1046 * Start the tracers here, after having set all instances.
1047 *
1048 * Let the trace instance start first for the case of hitting a stop
1049 * tracing while enabling other instances. The trace instance is the
1050 * one with most valuable information.
1051 */
1052 if (params->trace_output)
1053 trace_instance_start(&record->trace);
1054 if (!params->no_aa && aa != top)
1055 trace_instance_start(&aa->trace);
1056 trace_instance_start(trace);
1057
1058 top->start_time = time(NULL);
1059 timerlat_top_set_signals(params);
1060
1061 while (!stop_tracing) {
1062 sleep(params->sleep_time);
1063
1064 if (params->aa_only && !trace_is_off(&top->trace, &record->trace))
1065 continue;
1066
1067 retval = tracefs_iterate_raw_events(trace->tep,
1068 trace->inst,
1069 NULL,
1070 0,
1071 collect_registered_events,
1072 trace);
1073 if (retval < 0) {
1074 err_msg("Error iterating on events\n");
1075 goto out_top;
1076 }
1077
1078 if (!params->quiet)
1079 timerlat_print_stats(params, top);
1080
1081 if (trace_is_off(&top->trace, &record->trace))
1082 break;
1083
1084 /* is there still any user-threads ? */
1085 if (params->user_workload) {
1086 if (params_u.stopped_running) {
1087 debug_msg("timerlat user space threads stopped!\n");
1088 break;
1089 }
1090 }
1091 }
1092
1093 if (params->user_workload && !params_u.stopped_running) {
1094 params_u.should_run = 0;
1095 sleep(1);
1096 }
1097
1098 timerlat_print_stats(params, top);
1099
1100 return_value = 0;
1101
1102 if (trace_is_off(&top->trace, &record->trace)) {
1103 printf("rtla timerlat hit stop tracing\n");
1104
1105 if (!params->no_aa)
1106 timerlat_auto_analysis(params->stop_us, params->stop_total_us);
1107
1108 if (params->trace_output) {
1109 printf(" Saving trace to %s\n", params->trace_output);
1110 save_trace_to_file(record->trace.inst, params->trace_output);
1111 }
1112 } else if (params->aa_only) {
1113 /*
1114 * If the trace did not stop with --aa-only, at least print the
1115 * max known latency.
1116 */
1117 max_lat = tracefs_instance_file_read(trace->inst, "tracing_max_latency", NULL);
1118 if (max_lat) {
1119 printf(" Max latency was %s\n", max_lat);
1120 free(max_lat);
1121 }
1122 }
1123
1124 out_top:
1125 timerlat_aa_destroy();
1126 if (dma_latency_fd >= 0)
1127 close(dma_latency_fd);
1128 trace_events_destroy(&record->trace, params->events);
1129 params->events = NULL;
1130 out_free:
1131 timerlat_free_top(top->data);
1132 if (aa && aa != top)
1133 osnoise_destroy_tool(aa);
1134 osnoise_destroy_tool(record);
1135 osnoise_destroy_tool(top);
1136 free(params);
1137 out_exit:
1138 exit(return_value);
1139 }
1140
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