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_hist;
43 	cpu_set_t		hk_cpu_set;
44 	struct sched_attr	sched_param;
45 	struct trace_events	*events;
46 	char			no_irq;
47 	char			no_thread;
48 	char			no_header;
49 	char			no_summary;
50 	char			no_index;
51 	char			with_zeros;
52 	int			bucket_size;
53 	int			entries;
54 };
55 
56 struct timerlat_hist_cpu {
57 	int			*irq;
58 	int			*thread;
59 	int			*user;
60 
61 	int			irq_count;
62 	int			thread_count;
63 	int			user_count;
64 
65 	unsigned long long	min_irq;
66 	unsigned long long	sum_irq;
67 	unsigned long long	max_irq;
68 
69 	unsigned long long	min_thread;
70 	unsigned long long	sum_thread;
71 	unsigned long long	max_thread;
72 
73 	unsigned long long	min_user;
74 	unsigned long long	sum_user;
75 	unsigned long long	max_user;
76 };
77 
78 struct timerlat_hist_data {
79 	struct timerlat_hist_cpu	*hist;
80 	int				entries;
81 	int				bucket_size;
82 	int				nr_cpus;
83 };
84 
85 /*
86  * timerlat_free_histogram - free runtime data
87  */
88 static void
timerlat_free_histogram(struct timerlat_hist_data * data)89 timerlat_free_histogram(struct timerlat_hist_data *data)
90 {
91 	int cpu;
92 
93 	/* one histogram for IRQ and one for thread, per CPU */
94 	for (cpu = 0; cpu < data->nr_cpus; cpu++) {
95 		if (data->hist[cpu].irq)
96 			free(data->hist[cpu].irq);
97 
98 		if (data->hist[cpu].thread)
99 			free(data->hist[cpu].thread);
100 
101 		if (data->hist[cpu].user)
102 			free(data->hist[cpu].user);
103 
104 	}
105 
106 	/* one set of histograms per CPU */
107 	if (data->hist)
108 		free(data->hist);
109 
110 	free(data);
111 }
112 
113 /*
114  * timerlat_alloc_histogram - alloc runtime data
115  */
116 static struct timerlat_hist_data
timerlat_alloc_histogram(int nr_cpus,int entries,int bucket_size)117 *timerlat_alloc_histogram(int nr_cpus, int entries, int bucket_size)
118 {
119 	struct timerlat_hist_data *data;
120 	int cpu;
121 
122 	data = calloc(1, sizeof(*data));
123 	if (!data)
124 		return NULL;
125 
126 	data->entries = entries;
127 	data->bucket_size = bucket_size;
128 	data->nr_cpus = nr_cpus;
129 
130 	/* one set of histograms per CPU */
131 	data->hist = calloc(1, sizeof(*data->hist) * nr_cpus);
132 	if (!data->hist)
133 		goto cleanup;
134 
135 	/* one histogram for IRQ and one for thread, per cpu */
136 	for (cpu = 0; cpu < nr_cpus; cpu++) {
137 		data->hist[cpu].irq = calloc(1, sizeof(*data->hist->irq) * (entries + 1));
138 		if (!data->hist[cpu].irq)
139 			goto cleanup;
140 
141 		data->hist[cpu].thread = calloc(1, sizeof(*data->hist->thread) * (entries + 1));
142 		if (!data->hist[cpu].thread)
143 			goto cleanup;
144 
145 		data->hist[cpu].user = calloc(1, sizeof(*data->hist->user) * (entries + 1));
146 		if (!data->hist[cpu].user)
147 			goto cleanup;
148 	}
149 
150 	/* set the min to max */
151 	for (cpu = 0; cpu < nr_cpus; cpu++) {
152 		data->hist[cpu].min_irq = ~0;
153 		data->hist[cpu].min_thread = ~0;
154 		data->hist[cpu].min_user = ~0;
155 	}
156 
157 	return data;
158 
159 cleanup:
160 	timerlat_free_histogram(data);
161 	return NULL;
162 }
163 
164 /*
165  * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
166  */
167 static void
timerlat_hist_update(struct osnoise_tool * tool,int cpu,unsigned long long context,unsigned long long latency)168 timerlat_hist_update(struct osnoise_tool *tool, int cpu,
169 		     unsigned long long context,
170 		     unsigned long long latency)
171 {
172 	struct timerlat_hist_params *params = tool->params;
173 	struct timerlat_hist_data *data = tool->data;
174 	int entries = data->entries;
175 	int bucket;
176 	int *hist;
177 
178 	if (params->output_divisor)
179 		latency = latency / params->output_divisor;
180 
181 	bucket = latency / data->bucket_size;
182 
183 	if (!context) {
184 		hist = data->hist[cpu].irq;
185 		data->hist[cpu].irq_count++;
186 		update_min(&data->hist[cpu].min_irq, &latency);
187 		update_sum(&data->hist[cpu].sum_irq, &latency);
188 		update_max(&data->hist[cpu].max_irq, &latency);
189 	} else if (context == 1) {
190 		hist = data->hist[cpu].thread;
191 		data->hist[cpu].thread_count++;
192 		update_min(&data->hist[cpu].min_thread, &latency);
193 		update_sum(&data->hist[cpu].sum_thread, &latency);
194 		update_max(&data->hist[cpu].max_thread, &latency);
195 	} else { /* user */
196 		hist = data->hist[cpu].user;
197 		data->hist[cpu].user_count++;
198 		update_min(&data->hist[cpu].min_user, &latency);
199 		update_sum(&data->hist[cpu].sum_user, &latency);
200 		update_max(&data->hist[cpu].max_user, &latency);
201 	}
202 
203 	if (bucket < entries)
204 		hist[bucket]++;
205 	else
206 		hist[entries]++;
207 }
208 
209 /*
210  * timerlat_hist_handler - this is the handler for timerlat tracer events
211  */
212 static int
timerlat_hist_handler(struct trace_seq * s,struct tep_record * record,struct tep_event * event,void * data)213 timerlat_hist_handler(struct trace_seq *s, struct tep_record *record,
214 		     struct tep_event *event, void *data)
215 {
216 	struct trace_instance *trace = data;
217 	unsigned long long context, latency;
218 	struct osnoise_tool *tool;
219 	int cpu = record->cpu;
220 
221 	tool = container_of(trace, struct osnoise_tool, trace);
222 
223 	tep_get_field_val(s, event, "context", record, &context, 1);
224 	tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
225 
226 	timerlat_hist_update(tool, cpu, context, latency);
227 
228 	return 0;
229 }
230 
231 /*
232  * timerlat_hist_header - print the header of the tracer to the output
233  */
timerlat_hist_header(struct osnoise_tool * tool)234 static void timerlat_hist_header(struct osnoise_tool *tool)
235 {
236 	struct timerlat_hist_params *params = tool->params;
237 	struct timerlat_hist_data *data = tool->data;
238 	struct trace_seq *s = tool->trace.seq;
239 	char duration[26];
240 	int cpu;
241 
242 	if (params->no_header)
243 		return;
244 
245 	get_duration(tool->start_time, duration, sizeof(duration));
246 	trace_seq_printf(s, "# RTLA timerlat histogram\n");
247 	trace_seq_printf(s, "# Time unit is %s (%s)\n",
248 			params->output_divisor == 1 ? "nanoseconds" : "microseconds",
249 			params->output_divisor == 1 ? "ns" : "us");
250 
251 	trace_seq_printf(s, "# Duration: %s\n", duration);
252 
253 	if (!params->no_index)
254 		trace_seq_printf(s, "Index");
255 
256 	for (cpu = 0; cpu < data->nr_cpus; cpu++) {
257 		if (params->cpus && !CPU_ISSET(cpu, &params->monitored_cpus))
258 			continue;
259 
260 		if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
261 			continue;
262 
263 		if (!params->no_irq)
264 			trace_seq_printf(s, "   IRQ-%03d", cpu);
265 
266 		if (!params->no_thread)
267 			trace_seq_printf(s, "   Thr-%03d", cpu);
268 
269 		if (params->user_hist)
270 			trace_seq_printf(s, "   Usr-%03d", cpu);
271 	}
272 	trace_seq_printf(s, "\n");
273 
274 
275 	trace_seq_do_printf(s);
276 	trace_seq_reset(s);
277 }
278 
279 /*
280  * timerlat_print_summary - print the summary of the hist data to the output
281  */
282 static void
timerlat_print_summary(struct timerlat_hist_params * params,struct trace_instance * trace,struct timerlat_hist_data * data)283 timerlat_print_summary(struct timerlat_hist_params *params,
284 		       struct trace_instance *trace,
285 		       struct timerlat_hist_data *data)
286 {
287 	int cpu;
288 
289 	if (params->no_summary)
290 		return;
291 
292 	if (!params->no_index)
293 		trace_seq_printf(trace->seq, "count:");
294 
295 	for (cpu = 0; cpu < data->nr_cpus; cpu++) {
296 		if (params->cpus && !CPU_ISSET(cpu, &params->monitored_cpus))
297 			continue;
298 
299 		if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
300 			continue;
301 
302 		if (!params->no_irq)
303 			trace_seq_printf(trace->seq, "%9d ",
304 					data->hist[cpu].irq_count);
305 
306 		if (!params->no_thread)
307 			trace_seq_printf(trace->seq, "%9d ",
308 					data->hist[cpu].thread_count);
309 
310 		if (params->user_hist)
311 			trace_seq_printf(trace->seq, "%9d ",
312 					 data->hist[cpu].user_count);
313 	}
314 	trace_seq_printf(trace->seq, "\n");
315 
316 	if (!params->no_index)
317 		trace_seq_printf(trace->seq, "min:  ");
318 
319 	for (cpu = 0; cpu < data->nr_cpus; cpu++) {
320 		if (params->cpus && !CPU_ISSET(cpu, &params->monitored_cpus))
321 			continue;
322 
323 		if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
324 			continue;
325 
326 		if (!params->no_irq) {
327 			if (data->hist[cpu].irq_count)
328 				trace_seq_printf(trace->seq, "%9llu ",
329 						data->hist[cpu].min_irq);
330 			else
331 				trace_seq_printf(trace->seq, "        - ");
332 		}
333 
334 		if (!params->no_thread) {
335 			if (data->hist[cpu].thread_count)
336 				trace_seq_printf(trace->seq, "%9llu ",
337 						data->hist[cpu].min_thread);
338 			else
339 				trace_seq_printf(trace->seq, "        - ");
340 		}
341 
342 		if (params->user_hist) {
343 			if (data->hist[cpu].user_count)
344 				trace_seq_printf(trace->seq, "%9llu ",
345 						data->hist[cpu].min_user);
346 			else
347 				trace_seq_printf(trace->seq, "        - ");
348 		}
349 	}
350 	trace_seq_printf(trace->seq, "\n");
351 
352 	if (!params->no_index)
353 		trace_seq_printf(trace->seq, "avg:  ");
354 
355 	for (cpu = 0; cpu < data->nr_cpus; cpu++) {
356 		if (params->cpus && !CPU_ISSET(cpu, &params->monitored_cpus))
357 			continue;
358 
359 		if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
360 			continue;
361 
362 		if (!params->no_irq) {
363 			if (data->hist[cpu].irq_count)
364 				trace_seq_printf(trace->seq, "%9llu ",
365 						 data->hist[cpu].sum_irq / data->hist[cpu].irq_count);
366 			else
367 				trace_seq_printf(trace->seq, "        - ");
368 		}
369 
370 		if (!params->no_thread) {
371 			if (data->hist[cpu].thread_count)
372 				trace_seq_printf(trace->seq, "%9llu ",
373 						 data->hist[cpu].sum_thread / data->hist[cpu].thread_count);
374 			else
375 				trace_seq_printf(trace->seq, "        - ");
376 		}
377 
378 		if (params->user_hist) {
379 			if (data->hist[cpu].user_count)
380 				trace_seq_printf(trace->seq, "%9llu ",
381 						 data->hist[cpu].sum_user / data->hist[cpu].user_count);
382 			else
383 				trace_seq_printf(trace->seq, "        - ");
384 		}
385 	}
386 	trace_seq_printf(trace->seq, "\n");
387 
388 	if (!params->no_index)
389 		trace_seq_printf(trace->seq, "max:  ");
390 
391 	for (cpu = 0; cpu < data->nr_cpus; cpu++) {
392 		if (params->cpus && !CPU_ISSET(cpu, &params->monitored_cpus))
393 			continue;
394 
395 		if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
396 			continue;
397 
398 		if (!params->no_irq) {
399 			if (data->hist[cpu].irq_count)
400 				trace_seq_printf(trace->seq, "%9llu ",
401 						 data->hist[cpu].max_irq);
402 			else
403 				trace_seq_printf(trace->seq, "        - ");
404 		}
405 
406 		if (!params->no_thread) {
407 			if (data->hist[cpu].thread_count)
408 				trace_seq_printf(trace->seq, "%9llu ",
409 						data->hist[cpu].max_thread);
410 			else
411 				trace_seq_printf(trace->seq, "        - ");
412 		}
413 
414 		if (params->user_hist) {
415 			if (data->hist[cpu].user_count)
416 				trace_seq_printf(trace->seq, "%9llu ",
417 						data->hist[cpu].max_user);
418 			else
419 				trace_seq_printf(trace->seq, "        - ");
420 		}
421 	}
422 	trace_seq_printf(trace->seq, "\n");
423 	trace_seq_do_printf(trace->seq);
424 	trace_seq_reset(trace->seq);
425 }
426 
427 /*
428  * timerlat_print_stats - print data for all CPUs
429  */
430 static void
timerlat_print_stats(struct timerlat_hist_params * params,struct osnoise_tool * tool)431 timerlat_print_stats(struct timerlat_hist_params *params, struct osnoise_tool *tool)
432 {
433 	struct timerlat_hist_data *data = tool->data;
434 	struct trace_instance *trace = &tool->trace;
435 	int bucket, cpu;
436 	int total;
437 
438 	timerlat_hist_header(tool);
439 
440 	for (bucket = 0; bucket < data->entries; bucket++) {
441 		total = 0;
442 
443 		if (!params->no_index)
444 			trace_seq_printf(trace->seq, "%-6d",
445 					 bucket * data->bucket_size);
446 
447 		for (cpu = 0; cpu < data->nr_cpus; cpu++) {
448 			if (params->cpus && !CPU_ISSET(cpu, &params->monitored_cpus))
449 				continue;
450 
451 			if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
452 				continue;
453 
454 			if (!params->no_irq) {
455 				total += data->hist[cpu].irq[bucket];
456 				trace_seq_printf(trace->seq, "%9d ",
457 						data->hist[cpu].irq[bucket]);
458 			}
459 
460 			if (!params->no_thread) {
461 				total += data->hist[cpu].thread[bucket];
462 				trace_seq_printf(trace->seq, "%9d ",
463 						data->hist[cpu].thread[bucket]);
464 			}
465 
466 			if (params->user_hist) {
467 				total += data->hist[cpu].user[bucket];
468 				trace_seq_printf(trace->seq, "%9d ",
469 						data->hist[cpu].user[bucket]);
470 			}
471 
472 		}
473 
474 		if (total == 0 && !params->with_zeros) {
475 			trace_seq_reset(trace->seq);
476 			continue;
477 		}
478 
479 		trace_seq_printf(trace->seq, "\n");
480 		trace_seq_do_printf(trace->seq);
481 		trace_seq_reset(trace->seq);
482 	}
483 
484 	if (!params->no_index)
485 		trace_seq_printf(trace->seq, "over: ");
486 
487 	for (cpu = 0; cpu < data->nr_cpus; cpu++) {
488 		if (params->cpus && !CPU_ISSET(cpu, &params->monitored_cpus))
489 			continue;
490 
491 		if (!data->hist[cpu].irq_count && !data->hist[cpu].thread_count)
492 			continue;
493 
494 		if (!params->no_irq)
495 			trace_seq_printf(trace->seq, "%9d ",
496 					 data->hist[cpu].irq[data->entries]);
497 
498 		if (!params->no_thread)
499 			trace_seq_printf(trace->seq, "%9d ",
500 					 data->hist[cpu].thread[data->entries]);
501 
502 		if (params->user_hist)
503 			trace_seq_printf(trace->seq, "%9d ",
504 					 data->hist[cpu].user[data->entries]);
505 	}
506 	trace_seq_printf(trace->seq, "\n");
507 	trace_seq_do_printf(trace->seq);
508 	trace_seq_reset(trace->seq);
509 
510 	timerlat_print_summary(params, trace, data);
511 }
512 
513 /*
514  * timerlat_hist_usage - prints timerlat top usage message
515  */
timerlat_hist_usage(char * usage)516 static void timerlat_hist_usage(char *usage)
517 {
518 	int i;
519 
520 	char *msg[] = {
521 		"",
522 		"  usage: [rtla] timerlat hist [-h] [-q] [-d s] [-D] [-n] [-a us] [-p us] [-i us] [-T us] [-s us] \\",
523 		"         [-t[=file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
524 		"	  [-P priority] [-E N] [-b N] [--no-irq] [--no-thread] [--no-header] [--no-summary] \\",
525 		"	  [--no-index] [--with-zeros] [--dma-latency us] [-C[=cgroup_name]] [--no-aa] [--dump-task] [-u]",
526 		"",
527 		"	  -h/--help: print this menu",
528 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
529 		"	  -p/--period us: timerlat period in us",
530 		"	  -i/--irq us: stop trace if the irq latency is higher than the argument in us",
531 		"	  -T/--thread us: stop trace if the thread latency is higher than the argument in us",
532 		"	  -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
533 		"	  -c/--cpus cpus: run the tracer only on the given cpus",
534 		"	  -H/--house-keeping cpus: run rtla control threads only on the given cpus",
535 		"	  -C/--cgroup[=cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
536 		"	  -d/--duration time[m|h|d]: duration of the session in seconds",
537 		"	     --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)",
538 		"	  -D/--debug: print debug info",
539 		"	  -t/--trace[=file]: save the stopped trace to [file|timerlat_trace.txt]",
540 		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
541 		"	     --filter <filter>: enable a trace event filter to the previous -e event",
542 		"	     --trigger <trigger>: enable a trace event trigger to the previous -e event",
543 		"	  -n/--nano: display data in nanoseconds",
544 		"	     --no-aa: disable auto-analysis, reducing rtla timerlat cpu usage",
545 		"	  -b/--bucket-size N: set the histogram bucket size (default 1)",
546 		"	  -E/--entries N: set the number of entries of the histogram (default 256)",
547 		"	     --no-irq: ignore IRQ latencies",
548 		"	     --no-thread: ignore thread latencies",
549 		"	     --no-header: do not print header",
550 		"	     --no-summary: do not print summary",
551 		"	     --no-index: do not print index",
552 		"	     --with-zeros: print zero only entries",
553 		"	     --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency",
554 		"	  -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
555 		"		o:prio - use SCHED_OTHER with prio",
556 		"		r:prio - use SCHED_RR with prio",
557 		"		f:prio - use SCHED_FIFO with prio",
558 		"		d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period",
559 		"						       in nanoseconds",
560 		"	  -u/--user-threads: use rtla user-space threads instead of in-kernel timerlat threads",
561 		NULL,
562 	};
563 
564 	if (usage)
565 		fprintf(stderr, "%s\n", usage);
566 
567 	fprintf(stderr, "rtla timerlat hist: a per-cpu histogram of the timer latency (version %s)\n",
568 			VERSION);
569 
570 	for (i = 0; msg[i]; i++)
571 		fprintf(stderr, "%s\n", msg[i]);
572 
573 	if (usage)
574 		exit(EXIT_FAILURE);
575 
576 	exit(EXIT_SUCCESS);
577 }
578 
579 /*
580  * timerlat_hist_parse_args - allocs, parse and fill the cmd line parameters
581  */
582 static struct timerlat_hist_params
timerlat_hist_parse_args(int argc,char * argv[])583 *timerlat_hist_parse_args(int argc, char *argv[])
584 {
585 	struct timerlat_hist_params *params;
586 	struct trace_events *tevent;
587 	int auto_thresh;
588 	int retval;
589 	int c;
590 
591 	params = calloc(1, sizeof(*params));
592 	if (!params)
593 		exit(1);
594 
595 	/* disabled by default */
596 	params->dma_latency = -1;
597 
598 	/* display data in microseconds */
599 	params->output_divisor = 1000;
600 	params->bucket_size = 1;
601 	params->entries = 256;
602 
603 	while (1) {
604 		static struct option long_options[] = {
605 			{"auto",		required_argument,	0, 'a'},
606 			{"cpus",		required_argument,	0, 'c'},
607 			{"cgroup",		optional_argument,	0, 'C'},
608 			{"bucket-size",		required_argument,	0, 'b'},
609 			{"debug",		no_argument,		0, 'D'},
610 			{"entries",		required_argument,	0, 'E'},
611 			{"duration",		required_argument,	0, 'd'},
612 			{"house-keeping",	required_argument,	0, 'H'},
613 			{"help",		no_argument,		0, 'h'},
614 			{"irq",			required_argument,	0, 'i'},
615 			{"nano",		no_argument,		0, 'n'},
616 			{"period",		required_argument,	0, 'p'},
617 			{"priority",		required_argument,	0, 'P'},
618 			{"stack",		required_argument,	0, 's'},
619 			{"thread",		required_argument,	0, 'T'},
620 			{"trace",		optional_argument,	0, 't'},
621 			{"user-threads",	no_argument,		0, 'u'},
622 			{"event",		required_argument,	0, 'e'},
623 			{"no-irq",		no_argument,		0, '0'},
624 			{"no-thread",		no_argument,		0, '1'},
625 			{"no-header",		no_argument,		0, '2'},
626 			{"no-summary",		no_argument,		0, '3'},
627 			{"no-index",		no_argument,		0, '4'},
628 			{"with-zeros",		no_argument,		0, '5'},
629 			{"trigger",		required_argument,	0, '6'},
630 			{"filter",		required_argument,	0, '7'},
631 			{"dma-latency",		required_argument,	0, '8'},
632 			{"no-aa",		no_argument,		0, '9'},
633 			{"dump-task",		no_argument,		0, '\1'},
634 			{0, 0, 0, 0}
635 		};
636 
637 		/* getopt_long stores the option index here. */
638 		int option_index = 0;
639 
640 		c = getopt_long(argc, argv, "a:c:C::b:d:e:E:DhH:i:np:P:s:t::T:u0123456:7:8:9\1",
641 				 long_options, &option_index);
642 
643 		/* detect the end of the options. */
644 		if (c == -1)
645 			break;
646 
647 		switch (c) {
648 		case 'a':
649 			auto_thresh = get_llong_from_str(optarg);
650 
651 			/* set thread stop to auto_thresh */
652 			params->stop_total_us = auto_thresh;
653 			params->stop_us = auto_thresh;
654 
655 			/* get stack trace */
656 			params->print_stack = auto_thresh;
657 
658 			/* set trace */
659 			params->trace_output = "timerlat_trace.txt";
660 
661 			break;
662 		case 'c':
663 			retval = parse_cpu_set(optarg, &params->monitored_cpus);
664 			if (retval)
665 				timerlat_hist_usage("\nInvalid -c cpu list\n");
666 			params->cpus = optarg;
667 			break;
668 		case 'C':
669 			params->cgroup = 1;
670 			if (!optarg) {
671 				/* will inherit this cgroup */
672 				params->cgroup_name = NULL;
673 			} else if (*optarg == '=') {
674 				/* skip the = */
675 				params->cgroup_name = ++optarg;
676 			}
677 			break;
678 		case 'b':
679 			params->bucket_size = get_llong_from_str(optarg);
680 			if ((params->bucket_size == 0) || (params->bucket_size >= 1000000))
681 				timerlat_hist_usage("Bucket size needs to be > 0 and <= 1000000\n");
682 			break;
683 		case 'D':
684 			config_debug = 1;
685 			break;
686 		case 'd':
687 			params->duration = parse_seconds_duration(optarg);
688 			if (!params->duration)
689 				timerlat_hist_usage("Invalid -D duration\n");
690 			break;
691 		case 'e':
692 			tevent = trace_event_alloc(optarg);
693 			if (!tevent) {
694 				err_msg("Error alloc trace event");
695 				exit(EXIT_FAILURE);
696 			}
697 
698 			if (params->events)
699 				tevent->next = params->events;
700 
701 			params->events = tevent;
702 			break;
703 		case 'E':
704 			params->entries = get_llong_from_str(optarg);
705 			if ((params->entries < 10) || (params->entries > 9999999))
706 					timerlat_hist_usage("Entries must be > 10 and < 9999999\n");
707 			break;
708 		case 'h':
709 		case '?':
710 			timerlat_hist_usage(NULL);
711 			break;
712 		case 'H':
713 			params->hk_cpus = 1;
714 			retval = parse_cpu_set(optarg, &params->hk_cpu_set);
715 			if (retval) {
716 				err_msg("Error parsing house keeping CPUs\n");
717 				exit(EXIT_FAILURE);
718 			}
719 			break;
720 		case 'i':
721 			params->stop_us = get_llong_from_str(optarg);
722 			break;
723 		case 'n':
724 			params->output_divisor = 1;
725 			break;
726 		case 'p':
727 			params->timerlat_period_us = get_llong_from_str(optarg);
728 			if (params->timerlat_period_us > 1000000)
729 				timerlat_hist_usage("Period longer than 1 s\n");
730 			break;
731 		case 'P':
732 			retval = parse_prio(optarg, &params->sched_param);
733 			if (retval == -1)
734 				timerlat_hist_usage("Invalid -P priority");
735 			params->set_sched = 1;
736 			break;
737 		case 's':
738 			params->print_stack = get_llong_from_str(optarg);
739 			break;
740 		case 'T':
741 			params->stop_total_us = get_llong_from_str(optarg);
742 			break;
743 		case 't':
744 			if (optarg)
745 				/* skip = */
746 				params->trace_output = &optarg[1];
747 			else
748 				params->trace_output = "timerlat_trace.txt";
749 			break;
750 		case 'u':
751 			params->user_hist = 1;
752 			break;
753 		case '0': /* no irq */
754 			params->no_irq = 1;
755 			break;
756 		case '1': /* no thread */
757 			params->no_thread = 1;
758 			break;
759 		case '2': /* no header */
760 			params->no_header = 1;
761 			break;
762 		case '3': /* no summary */
763 			params->no_summary = 1;
764 			break;
765 		case '4': /* no index */
766 			params->no_index = 1;
767 			break;
768 		case '5': /* with zeros */
769 			params->with_zeros = 1;
770 			break;
771 		case '6': /* trigger */
772 			if (params->events) {
773 				retval = trace_event_add_trigger(params->events, optarg);
774 				if (retval) {
775 					err_msg("Error adding trigger %s\n", optarg);
776 					exit(EXIT_FAILURE);
777 				}
778 			} else {
779 				timerlat_hist_usage("--trigger requires a previous -e\n");
780 			}
781 			break;
782 		case '7': /* filter */
783 			if (params->events) {
784 				retval = trace_event_add_filter(params->events, optarg);
785 				if (retval) {
786 					err_msg("Error adding filter %s\n", optarg);
787 					exit(EXIT_FAILURE);
788 				}
789 			} else {
790 				timerlat_hist_usage("--filter requires a previous -e\n");
791 			}
792 			break;
793 		case '8':
794 			params->dma_latency = get_llong_from_str(optarg);
795 			if (params->dma_latency < 0 || params->dma_latency > 10000) {
796 				err_msg("--dma-latency needs to be >= 0 and < 10000");
797 				exit(EXIT_FAILURE);
798 			}
799 			break;
800 		case '9':
801 			params->no_aa = 1;
802 			break;
803 		case '\1':
804 			params->dump_tasks = 1;
805 			break;
806 		default:
807 			timerlat_hist_usage("Invalid option");
808 		}
809 	}
810 
811 	if (geteuid()) {
812 		err_msg("rtla needs root permission\n");
813 		exit(EXIT_FAILURE);
814 	}
815 
816 	if (params->no_irq && params->no_thread)
817 		timerlat_hist_usage("no-irq and no-thread set, there is nothing to do here");
818 
819 	if (params->no_index && !params->with_zeros)
820 		timerlat_hist_usage("no-index set with with-zeros is not set - it does not make sense");
821 
822 	/*
823 	 * Auto analysis only happens if stop tracing, thus:
824 	 */
825 	if (!params->stop_us && !params->stop_total_us)
826 		params->no_aa = 1;
827 
828 	return params;
829 }
830 
831 /*
832  * timerlat_hist_apply_config - apply the hist configs to the initialized tool
833  */
834 static int
timerlat_hist_apply_config(struct osnoise_tool * tool,struct timerlat_hist_params * params)835 timerlat_hist_apply_config(struct osnoise_tool *tool, struct timerlat_hist_params *params)
836 {
837 	int retval, i;
838 
839 	if (!params->sleep_time)
840 		params->sleep_time = 1;
841 
842 	if (params->cpus) {
843 		retval = osnoise_set_cpus(tool->context, params->cpus);
844 		if (retval) {
845 			err_msg("Failed to apply CPUs config\n");
846 			goto out_err;
847 		}
848 	} else {
849 		for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++)
850 			CPU_SET(i, &params->monitored_cpus);
851 	}
852 
853 	if (params->stop_us) {
854 		retval = osnoise_set_stop_us(tool->context, params->stop_us);
855 		if (retval) {
856 			err_msg("Failed to set stop us\n");
857 			goto out_err;
858 		}
859 	}
860 
861 	if (params->stop_total_us) {
862 		retval = osnoise_set_stop_total_us(tool->context, params->stop_total_us);
863 		if (retval) {
864 			err_msg("Failed to set stop total us\n");
865 			goto out_err;
866 		}
867 	}
868 
869 	if (params->timerlat_period_us) {
870 		retval = osnoise_set_timerlat_period_us(tool->context, params->timerlat_period_us);
871 		if (retval) {
872 			err_msg("Failed to set timerlat period\n");
873 			goto out_err;
874 		}
875 	}
876 
877 	if (params->print_stack) {
878 		retval = osnoise_set_print_stack(tool->context, params->print_stack);
879 		if (retval) {
880 			err_msg("Failed to set print stack\n");
881 			goto out_err;
882 		}
883 	}
884 
885 	if (params->hk_cpus) {
886 		retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set),
887 					   &params->hk_cpu_set);
888 		if (retval == -1) {
889 			err_msg("Failed to set rtla to the house keeping CPUs\n");
890 			goto out_err;
891 		}
892 	} else if (params->cpus) {
893 		/*
894 		 * Even if the user do not set a house-keeping CPU, try to
895 		 * move rtla to a CPU set different to the one where the user
896 		 * set the workload to run.
897 		 *
898 		 * No need to check results as this is an automatic attempt.
899 		 */
900 		auto_house_keeping(&params->monitored_cpus);
901 	}
902 
903 	if (params->user_hist) {
904 		retval = osnoise_set_workload(tool->context, 0);
905 		if (retval) {
906 			err_msg("Failed to set OSNOISE_WORKLOAD option\n");
907 			goto out_err;
908 		}
909 	}
910 
911 	return 0;
912 
913 out_err:
914 	return -1;
915 }
916 
917 /*
918  * timerlat_init_hist - initialize a timerlat hist tool with parameters
919  */
920 static struct osnoise_tool
timerlat_init_hist(struct timerlat_hist_params * params)921 *timerlat_init_hist(struct timerlat_hist_params *params)
922 {
923 	struct osnoise_tool *tool;
924 	int nr_cpus;
925 
926 	nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
927 
928 	tool = osnoise_init_tool("timerlat_hist");
929 	if (!tool)
930 		return NULL;
931 
932 	tool->data = timerlat_alloc_histogram(nr_cpus, params->entries, params->bucket_size);
933 	if (!tool->data)
934 		goto out_err;
935 
936 	tool->params = params;
937 
938 	tep_register_event_handler(tool->trace.tep, -1, "ftrace", "timerlat",
939 				   timerlat_hist_handler, tool);
940 
941 	return tool;
942 
943 out_err:
944 	osnoise_destroy_tool(tool);
945 	return NULL;
946 }
947 
948 static int stop_tracing;
stop_hist(int sig)949 static void stop_hist(int sig)
950 {
951 	stop_tracing = 1;
952 }
953 
954 /*
955  * timerlat_hist_set_signals - handles the signal to stop the tool
956  */
957 static void
timerlat_hist_set_signals(struct timerlat_hist_params * params)958 timerlat_hist_set_signals(struct timerlat_hist_params *params)
959 {
960 	signal(SIGINT, stop_hist);
961 	if (params->duration) {
962 		signal(SIGALRM, stop_hist);
963 		alarm(params->duration);
964 	}
965 }
966 
timerlat_hist_main(int argc,char * argv[])967 int timerlat_hist_main(int argc, char *argv[])
968 {
969 	struct timerlat_hist_params *params;
970 	struct osnoise_tool *record = NULL;
971 	struct timerlat_u_params params_u;
972 	struct osnoise_tool *tool = NULL;
973 	struct osnoise_tool *aa = NULL;
974 	struct trace_instance *trace;
975 	int dma_latency_fd = -1;
976 	int return_value = 1;
977 	pthread_t timerlat_u;
978 	int retval;
979 
980 	params = timerlat_hist_parse_args(argc, argv);
981 	if (!params)
982 		exit(1);
983 
984 	tool = timerlat_init_hist(params);
985 	if (!tool) {
986 		err_msg("Could not init osnoise hist\n");
987 		goto out_exit;
988 	}
989 
990 	retval = timerlat_hist_apply_config(tool, params);
991 	if (retval) {
992 		err_msg("Could not apply config\n");
993 		goto out_free;
994 	}
995 
996 	trace = &tool->trace;
997 
998 	retval = enable_timerlat(trace);
999 	if (retval) {
1000 		err_msg("Failed to enable timerlat tracer\n");
1001 		goto out_free;
1002 	}
1003 
1004 	if (params->set_sched) {
1005 		retval = set_comm_sched_attr("timerlat/", &params->sched_param);
1006 		if (retval) {
1007 			err_msg("Failed to set sched parameters\n");
1008 			goto out_free;
1009 		}
1010 	}
1011 
1012 	if (params->cgroup && !params->user_hist) {
1013 		retval = set_comm_cgroup("timerlat/", params->cgroup_name);
1014 		if (!retval) {
1015 			err_msg("Failed to move threads to cgroup\n");
1016 			goto out_free;
1017 		}
1018 	}
1019 
1020 	if (params->dma_latency >= 0) {
1021 		dma_latency_fd = set_cpu_dma_latency(params->dma_latency);
1022 		if (dma_latency_fd < 0) {
1023 			err_msg("Could not set /dev/cpu_dma_latency.\n");
1024 			goto out_free;
1025 		}
1026 	}
1027 
1028 	if (params->trace_output) {
1029 		record = osnoise_init_trace_tool("timerlat");
1030 		if (!record) {
1031 			err_msg("Failed to enable the trace instance\n");
1032 			goto out_free;
1033 		}
1034 
1035 		if (params->events) {
1036 			retval = trace_events_enable(&record->trace, params->events);
1037 			if (retval)
1038 				goto out_hist;
1039 		}
1040 	}
1041 
1042 	if (!params->no_aa) {
1043 		aa = osnoise_init_tool("timerlat_aa");
1044 		if (!aa)
1045 			goto out_hist;
1046 
1047 		retval = timerlat_aa_init(aa, params->dump_tasks);
1048 		if (retval) {
1049 			err_msg("Failed to enable the auto analysis instance\n");
1050 			goto out_hist;
1051 		}
1052 
1053 		retval = enable_timerlat(&aa->trace);
1054 		if (retval) {
1055 			err_msg("Failed to enable timerlat tracer\n");
1056 			goto out_hist;
1057 		}
1058 	}
1059 
1060 	/*
1061 	 * Start the tracers here, after having set all instances.
1062 	 *
1063 	 * Let the trace instance start first for the case of hitting a stop
1064 	 * tracing while enabling other instances. The trace instance is the
1065 	 * one with most valuable information.
1066 	 */
1067 	if (params->trace_output)
1068 		trace_instance_start(&record->trace);
1069 	if (!params->no_aa)
1070 		trace_instance_start(&aa->trace);
1071 	trace_instance_start(trace);
1072 
1073 	tool->start_time = time(NULL);
1074 	timerlat_hist_set_signals(params);
1075 
1076 	if (params->user_hist) {
1077 		/* rtla asked to stop */
1078 		params_u.should_run = 1;
1079 		/* all threads left */
1080 		params_u.stopped_running = 0;
1081 
1082 		params_u.set = &params->monitored_cpus;
1083 		if (params->set_sched)
1084 			params_u.sched_param = &params->sched_param;
1085 		else
1086 			params_u.sched_param = NULL;
1087 
1088 		params_u.cgroup_name = params->cgroup_name;
1089 
1090 		retval = pthread_create(&timerlat_u, NULL, timerlat_u_dispatcher, &params_u);
1091 		if (retval)
1092 			err_msg("Error creating timerlat user-space threads\n");
1093 	}
1094 
1095 	while (!stop_tracing) {
1096 		sleep(params->sleep_time);
1097 
1098 		retval = tracefs_iterate_raw_events(trace->tep,
1099 						    trace->inst,
1100 						    NULL,
1101 						    0,
1102 						    collect_registered_events,
1103 						    trace);
1104 		if (retval < 0) {
1105 			err_msg("Error iterating on events\n");
1106 			goto out_hist;
1107 		}
1108 
1109 		if (trace_is_off(&tool->trace, &record->trace))
1110 			break;
1111 
1112 		/* is there still any user-threads ? */
1113 		if (params->user_hist) {
1114 			if (params_u.stopped_running) {
1115 				debug_msg("timerlat user-space threads stopped!\n");
1116 				break;
1117 			}
1118 		}
1119 	}
1120 	if (params->user_hist && !params_u.stopped_running) {
1121 		params_u.should_run = 0;
1122 		sleep(1);
1123 	}
1124 
1125 	timerlat_print_stats(params, tool);
1126 
1127 	return_value = 0;
1128 
1129 	if (trace_is_off(&tool->trace, &record->trace)) {
1130 		printf("rtla timerlat hit stop tracing\n");
1131 
1132 		if (!params->no_aa)
1133 			timerlat_auto_analysis(params->stop_us, params->stop_total_us);
1134 
1135 		if (params->trace_output) {
1136 			printf("  Saving trace to %s\n", params->trace_output);
1137 			save_trace_to_file(record->trace.inst, params->trace_output);
1138 		}
1139 	}
1140 
1141 out_hist:
1142 	timerlat_aa_destroy();
1143 	if (dma_latency_fd >= 0)
1144 		close(dma_latency_fd);
1145 	trace_events_destroy(&record->trace, params->events);
1146 	params->events = NULL;
1147 out_free:
1148 	timerlat_free_histogram(tool->data);
1149 	osnoise_destroy_tool(aa);
1150 	osnoise_destroy_tool(record);
1151 	osnoise_destroy_tool(tool);
1152 	free(params);
1153 out_exit:
1154 	exit(return_value);
1155 }
1156