xref: /linux/tools/tracing/rtla/src/timerlat_top.c (revision f3cc3e4b5116929ebff27c3b0a565b34ae4969b3)
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 "timerlat.h"
18 #include "timerlat_aa.h"
19 #include "timerlat_bpf.h"
20 
21 struct timerlat_top_cpu {
22 	unsigned long long	irq_count;
23 	unsigned long long	thread_count;
24 	unsigned long long	user_count;
25 
26 	unsigned long long	cur_irq;
27 	unsigned long long	min_irq;
28 	unsigned long long	sum_irq;
29 	unsigned long long	max_irq;
30 
31 	unsigned long long	cur_thread;
32 	unsigned long long	min_thread;
33 	unsigned long long	sum_thread;
34 	unsigned long long	max_thread;
35 
36 	unsigned long long	cur_user;
37 	unsigned long long	min_user;
38 	unsigned long long	sum_user;
39 	unsigned long long	max_user;
40 };
41 
42 struct timerlat_top_data {
43 	struct timerlat_top_cpu	*cpu_data;
44 	int			nr_cpus;
45 };
46 
47 /*
48  * timerlat_free_top - free runtime data
49  */
50 static void timerlat_free_top(struct timerlat_top_data *data)
51 {
52 	free(data->cpu_data);
53 	free(data);
54 }
55 
56 static void timerlat_free_top_tool(struct osnoise_tool *tool)
57 {
58 	timerlat_free_top(tool->data);
59 	timerlat_free(tool);
60 }
61 
62 /*
63  * timerlat_alloc_histogram - alloc runtime data
64  */
65 static struct timerlat_top_data *timerlat_alloc_top(int nr_cpus)
66 {
67 	struct timerlat_top_data *data;
68 	int cpu;
69 
70 	data = calloc(1, sizeof(*data));
71 	if (!data)
72 		return NULL;
73 
74 	data->nr_cpus = nr_cpus;
75 
76 	/* one set of histograms per CPU */
77 	data->cpu_data = calloc(1, sizeof(*data->cpu_data) * nr_cpus);
78 	if (!data->cpu_data)
79 		goto cleanup;
80 
81 	/* set the min to max */
82 	for (cpu = 0; cpu < nr_cpus; cpu++) {
83 		data->cpu_data[cpu].min_irq = ~0;
84 		data->cpu_data[cpu].min_thread = ~0;
85 		data->cpu_data[cpu].min_user = ~0;
86 	}
87 
88 	return data;
89 
90 cleanup:
91 	timerlat_free_top(data);
92 	return NULL;
93 }
94 
95 static void
96 timerlat_top_reset_sum(struct timerlat_top_cpu *summary)
97 {
98 	memset(summary, 0, sizeof(*summary));
99 	summary->min_irq = ~0;
100 	summary->min_thread = ~0;
101 	summary->min_user = ~0;
102 }
103 
104 static void
105 timerlat_top_update_sum(struct osnoise_tool *tool, int cpu, struct timerlat_top_cpu *sum)
106 {
107 	struct timerlat_top_data *data = tool->data;
108 	struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
109 
110 	sum->irq_count += cpu_data->irq_count;
111 	update_min(&sum->min_irq, &cpu_data->min_irq);
112 	update_sum(&sum->sum_irq, &cpu_data->sum_irq);
113 	update_max(&sum->max_irq, &cpu_data->max_irq);
114 
115 	sum->thread_count += cpu_data->thread_count;
116 	update_min(&sum->min_thread, &cpu_data->min_thread);
117 	update_sum(&sum->sum_thread, &cpu_data->sum_thread);
118 	update_max(&sum->max_thread, &cpu_data->max_thread);
119 
120 	sum->user_count += cpu_data->user_count;
121 	update_min(&sum->min_user, &cpu_data->min_user);
122 	update_sum(&sum->sum_user, &cpu_data->sum_user);
123 	update_max(&sum->max_user, &cpu_data->max_user);
124 }
125 
126 /*
127  * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
128  */
129 static void
130 timerlat_top_update(struct osnoise_tool *tool, int cpu,
131 		    unsigned long long thread,
132 		    unsigned long long latency)
133 {
134 	struct timerlat_params *params = to_timerlat_params(tool->params);
135 	struct timerlat_top_data *data = tool->data;
136 	struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
137 
138 	if (params->common.output_divisor)
139 		latency = latency / params->common.output_divisor;
140 
141 	if (!thread) {
142 		cpu_data->irq_count++;
143 		cpu_data->cur_irq = latency;
144 		update_min(&cpu_data->min_irq, &latency);
145 		update_sum(&cpu_data->sum_irq, &latency);
146 		update_max(&cpu_data->max_irq, &latency);
147 	} else if (thread == 1) {
148 		cpu_data->thread_count++;
149 		cpu_data->cur_thread = latency;
150 		update_min(&cpu_data->min_thread, &latency);
151 		update_sum(&cpu_data->sum_thread, &latency);
152 		update_max(&cpu_data->max_thread, &latency);
153 	} else {
154 		cpu_data->user_count++;
155 		cpu_data->cur_user = latency;
156 		update_min(&cpu_data->min_user, &latency);
157 		update_sum(&cpu_data->sum_user, &latency);
158 		update_max(&cpu_data->max_user, &latency);
159 	}
160 }
161 
162 /*
163  * timerlat_top_handler - this is the handler for timerlat tracer events
164  */
165 static int
166 timerlat_top_handler(struct trace_seq *s, struct tep_record *record,
167 		     struct tep_event *event, void *context)
168 {
169 	struct trace_instance *trace = context;
170 	unsigned long long latency, thread;
171 	struct osnoise_tool *top;
172 	int cpu = record->cpu;
173 
174 	top = container_of(trace, struct osnoise_tool, trace);
175 
176 	if (!top->params->aa_only) {
177 		tep_get_field_val(s, event, "context", record, &thread, 1);
178 		tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
179 
180 		timerlat_top_update(top, cpu, thread, latency);
181 	}
182 
183 	return 0;
184 }
185 
186 /*
187  * timerlat_top_bpf_pull_data - copy data from BPF maps into userspace
188  */
189 static int timerlat_top_bpf_pull_data(struct osnoise_tool *tool)
190 {
191 	struct timerlat_top_data *data = tool->data;
192 	int i, err;
193 	long long value_irq[data->nr_cpus],
194 		  value_thread[data->nr_cpus],
195 		  value_user[data->nr_cpus];
196 
197 	/* Pull summary */
198 	err = timerlat_bpf_get_summary_value(SUMMARY_CURRENT,
199 					     value_irq, value_thread, value_user,
200 					     data->nr_cpus);
201 	if (err)
202 		return err;
203 	for (i = 0; i < data->nr_cpus; i++) {
204 		data->cpu_data[i].cur_irq = value_irq[i];
205 		data->cpu_data[i].cur_thread = value_thread[i];
206 		data->cpu_data[i].cur_user = value_user[i];
207 	}
208 
209 	err = timerlat_bpf_get_summary_value(SUMMARY_COUNT,
210 					     value_irq, value_thread, value_user,
211 					     data->nr_cpus);
212 	if (err)
213 		return err;
214 	for (i = 0; i < data->nr_cpus; i++) {
215 		data->cpu_data[i].irq_count = value_irq[i];
216 		data->cpu_data[i].thread_count = value_thread[i];
217 		data->cpu_data[i].user_count = value_user[i];
218 	}
219 
220 	err = timerlat_bpf_get_summary_value(SUMMARY_MIN,
221 					     value_irq, value_thread, value_user,
222 					     data->nr_cpus);
223 	if (err)
224 		return err;
225 	for (i = 0; i < data->nr_cpus; i++) {
226 		data->cpu_data[i].min_irq = value_irq[i];
227 		data->cpu_data[i].min_thread = value_thread[i];
228 		data->cpu_data[i].min_user = value_user[i];
229 	}
230 
231 	err = timerlat_bpf_get_summary_value(SUMMARY_MAX,
232 					     value_irq, value_thread, value_user,
233 					     data->nr_cpus);
234 	if (err)
235 		return err;
236 	for (i = 0; i < data->nr_cpus; i++) {
237 		data->cpu_data[i].max_irq = value_irq[i];
238 		data->cpu_data[i].max_thread = value_thread[i];
239 		data->cpu_data[i].max_user = value_user[i];
240 	}
241 
242 	err = timerlat_bpf_get_summary_value(SUMMARY_SUM,
243 					     value_irq, value_thread, value_user,
244 					     data->nr_cpus);
245 	if (err)
246 		return err;
247 	for (i = 0; i < data->nr_cpus; i++) {
248 		data->cpu_data[i].sum_irq = value_irq[i];
249 		data->cpu_data[i].sum_thread = value_thread[i];
250 		data->cpu_data[i].sum_user = value_user[i];
251 	}
252 
253 	return 0;
254 }
255 
256 /*
257  * timerlat_top_header - print the header of the tool output
258  */
259 static void timerlat_top_header(struct timerlat_params *params, struct osnoise_tool *top)
260 {
261 	struct trace_seq *s = top->trace.seq;
262 	bool pretty = params->common.pretty_output;
263 	char duration[26];
264 
265 	get_duration(top->start_time, duration, sizeof(duration));
266 
267 	if (pretty)
268 		trace_seq_printf(s, "\033[2;37;40m");
269 
270 	trace_seq_printf(s, "                                     Timer Latency                                              ");
271 	if (params->common.user_data)
272 		trace_seq_printf(s, "                                         ");
273 
274 	if (pretty)
275 		trace_seq_printf(s, "\033[0;0;0m");
276 	trace_seq_printf(s, "\n");
277 
278 	trace_seq_printf(s, "%-6s   |          IRQ Timer Latency (%s)        |         Thread Timer Latency (%s)", duration,
279 			params->common.output_divisor == 1 ? "ns" : "us",
280 			params->common.output_divisor == 1 ? "ns" : "us");
281 
282 	if (params->common.user_data) {
283 		trace_seq_printf(s, "      |    Ret user Timer Latency (%s)",
284 				params->common.output_divisor == 1 ? "ns" : "us");
285 	}
286 
287 	trace_seq_printf(s, "\n");
288 	if (pretty)
289 		trace_seq_printf(s, "\033[2;30;47m");
290 
291 	trace_seq_printf(s, "CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max");
292 	if (params->common.user_data)
293 		trace_seq_printf(s, " |      cur       min       avg       max");
294 
295 	if (pretty)
296 		trace_seq_printf(s, "\033[0;0;0m");
297 	trace_seq_printf(s, "\n");
298 }
299 
300 static const char *no_value = "        -";
301 
302 /*
303  * timerlat_top_print - prints the output of a given CPU
304  */
305 static void timerlat_top_print(struct osnoise_tool *top, int cpu)
306 {
307 	struct timerlat_params *params = to_timerlat_params(top->params);
308 	struct timerlat_top_data *data = top->data;
309 	struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
310 	struct trace_seq *s = top->trace.seq;
311 
312 	/*
313 	 * Skip if no data is available: is this cpu offline?
314 	 */
315 	if (!cpu_data->irq_count && !cpu_data->thread_count)
316 		return;
317 
318 	/*
319 	 * Unless trace is being lost, IRQ counter is always the max.
320 	 */
321 	trace_seq_printf(s, "%3d #%-9llu |", cpu, cpu_data->irq_count);
322 
323 	if (!cpu_data->irq_count) {
324 		trace_seq_printf(s, "%s %s %s %s |", no_value, no_value, no_value, no_value);
325 	} else {
326 		trace_seq_printf(s, "%9llu ", cpu_data->cur_irq);
327 		trace_seq_printf(s, "%9llu ", cpu_data->min_irq);
328 		trace_seq_printf(s, "%9llu ", cpu_data->sum_irq / cpu_data->irq_count);
329 		trace_seq_printf(s, "%9llu |", cpu_data->max_irq);
330 	}
331 
332 	if (!cpu_data->thread_count) {
333 		trace_seq_printf(s, "%s %s %s %s", no_value, no_value, no_value, no_value);
334 	} else {
335 		trace_seq_printf(s, "%9llu ", cpu_data->cur_thread);
336 		trace_seq_printf(s, "%9llu ", cpu_data->min_thread);
337 		trace_seq_printf(s, "%9llu ",
338 				cpu_data->sum_thread / cpu_data->thread_count);
339 		trace_seq_printf(s, "%9llu", cpu_data->max_thread);
340 	}
341 
342 	if (!params->common.user_data) {
343 		trace_seq_printf(s, "\n");
344 		return;
345 	}
346 
347 	trace_seq_printf(s, " |");
348 
349 	if (!cpu_data->user_count) {
350 		trace_seq_printf(s, "%s %s %s %s\n", no_value, no_value, no_value, no_value);
351 	} else {
352 		trace_seq_printf(s, "%9llu ", cpu_data->cur_user);
353 		trace_seq_printf(s, "%9llu ", cpu_data->min_user);
354 		trace_seq_printf(s, "%9llu ",
355 				cpu_data->sum_user / cpu_data->user_count);
356 		trace_seq_printf(s, "%9llu\n", cpu_data->max_user);
357 	}
358 }
359 
360 /*
361  * timerlat_top_print_sum - prints the summary output
362  */
363 static void
364 timerlat_top_print_sum(struct osnoise_tool *top, struct timerlat_top_cpu *summary)
365 {
366 	const char *split = "----------------------------------------";
367 	struct timerlat_params *params = to_timerlat_params(top->params);
368 	unsigned long long count = summary->irq_count;
369 	struct trace_seq *s = top->trace.seq;
370 	int e = 0;
371 
372 	/*
373 	 * Skip if no data is available: is this cpu offline?
374 	 */
375 	if (!summary->irq_count && !summary->thread_count)
376 		return;
377 
378 	while (count > 999999) {
379 		e++;
380 		count /= 10;
381 	}
382 
383 	trace_seq_printf(s, "%.*s|%.*s|%.*s", 15, split, 40, split, 39, split);
384 	if (params->common.user_data)
385 		trace_seq_printf(s, "-|%.*s", 39, split);
386 	trace_seq_printf(s, "\n");
387 
388 	trace_seq_printf(s, "ALL #%-6llu e%d |", count, e);
389 
390 	if (!summary->irq_count) {
391 		trace_seq_printf(s, "          %s %s %s |", no_value, no_value, no_value);
392 	} else {
393 		trace_seq_printf(s, "          ");
394 		trace_seq_printf(s, "%9llu ", summary->min_irq);
395 		trace_seq_printf(s, "%9llu ", summary->sum_irq / summary->irq_count);
396 		trace_seq_printf(s, "%9llu |", summary->max_irq);
397 	}
398 
399 	if (!summary->thread_count) {
400 		trace_seq_printf(s, "%s %s %s %s", no_value, no_value, no_value, no_value);
401 	} else {
402 		trace_seq_printf(s, "          ");
403 		trace_seq_printf(s, "%9llu ", summary->min_thread);
404 		trace_seq_printf(s, "%9llu ",
405 				summary->sum_thread / summary->thread_count);
406 		trace_seq_printf(s, "%9llu", summary->max_thread);
407 	}
408 
409 	if (!params->common.user_data) {
410 		trace_seq_printf(s, "\n");
411 		return;
412 	}
413 
414 	trace_seq_printf(s, " |");
415 
416 	if (!summary->user_count) {
417 		trace_seq_printf(s, "          %s %s %s |", no_value, no_value, no_value);
418 	} else {
419 		trace_seq_printf(s, "          ");
420 		trace_seq_printf(s, "%9llu ", summary->min_user);
421 		trace_seq_printf(s, "%9llu ",
422 				summary->sum_user / summary->user_count);
423 		trace_seq_printf(s, "%9llu\n", summary->max_user);
424 	}
425 }
426 
427 /*
428  * clear_terminal - clears the output terminal
429  */
430 static void clear_terminal(struct trace_seq *seq)
431 {
432 	if (!config_debug)
433 		trace_seq_printf(seq, "\033c");
434 }
435 
436 /*
437  * timerlat_print_stats - print data for all cpus
438  */
439 static void
440 timerlat_print_stats(struct osnoise_tool *top)
441 {
442 	struct timerlat_params *params = to_timerlat_params(top->params);
443 	struct trace_instance *trace = &top->trace;
444 	struct timerlat_top_cpu summary;
445 	static int nr_cpus = -1;
446 	int i;
447 
448 	if (params->common.aa_only)
449 		return;
450 
451 	if (nr_cpus == -1)
452 		nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
453 
454 	if (!params->common.quiet)
455 		clear_terminal(trace->seq);
456 
457 	timerlat_top_reset_sum(&summary);
458 
459 	timerlat_top_header(params, top);
460 
461 	for_each_monitored_cpu(i, nr_cpus, &params->common) {
462 		timerlat_top_print(top, i);
463 		timerlat_top_update_sum(top, i, &summary);
464 	}
465 
466 	timerlat_top_print_sum(top, &summary);
467 
468 	trace_seq_do_printf(trace->seq);
469 	trace_seq_reset(trace->seq);
470 	osnoise_report_missed_events(top);
471 }
472 
473 /*
474  * timerlat_top_usage - prints timerlat top usage message
475  */
476 static void timerlat_top_usage(void)
477 {
478 	static const char *const msg_start[] = {
479 		"[-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\",
480 		"	  [[-t [file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
481 		"	  [-P priority] [--dma-latency us] [--aa-only us] [-C [cgroup_name]] [-u|-k] [--warm-up s] [--deepest-idle-state n]",
482 		NULL,
483 	};
484 
485 	static const char *const msg_opts[] = {
486 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
487 		"	     --aa-only us: stop if <us> latency is hit, only printing the auto analysis (reduces CPU usage)",
488 		"	  -p/--period us: timerlat period in us",
489 		"	  -i/--irq us: stop trace if the irq latency is higher than the argument in us",
490 		"	  -T/--thread us: stop trace if the thread latency is higher than the argument in us",
491 		"	  -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
492 		"	  -c/--cpus cpus: run the tracer only on the given cpus",
493 		"	  -H/--house-keeping cpus: run rtla control threads only on the given cpus",
494 		"	  -C/--cgroup [cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
495 		"	  -d/--duration time[s|m|h|d]: duration of the session",
496 		"	  -D/--debug: print debug info",
497 		"	     --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)",
498 		"	  -t/--trace [file]: save the stopped trace to [file|timerlat_trace.txt]",
499 		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
500 		"	     --filter <command>: enable a trace event filter to the previous -e event",
501 		"	     --trigger <command>: enable a trace event trigger to the previous -e event",
502 		"	  -n/--nano: display data in nanoseconds",
503 		"	     --no-aa: disable auto-analysis, reducing rtla timerlat cpu usage",
504 		"	  -q/--quiet print only a summary at the end",
505 		"	     --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency",
506 		"	  -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
507 		"		o:prio - use SCHED_OTHER with prio",
508 		"		r:prio - use SCHED_RR with prio",
509 		"		f:prio - use SCHED_FIFO with prio",
510 		"		d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period",
511 		"						       in nanoseconds",
512 		"	  -u/--user-threads: use rtla user-space threads instead of kernel-space timerlat threads",
513 		"	  -k/--kernel-threads: use timerlat kernel-space threads instead of rtla user-space threads",
514 		"	  -U/--user-load: enable timerlat for user-defined user-space workload",
515 		"	     --warm-up s: let the workload run for s seconds before collecting data",
516 		"	     --trace-buffer-size kB: set the per-cpu trace buffer size in kB",
517 		"	     --deepest-idle-state n: only go down to idle state n on cpus used by timerlat to reduce exit from idle latency",
518 		"	     --on-threshold <action>: define action to be executed at latency threshold, multiple are allowed",
519 		"	     --on-end: define action to be executed at measurement end, multiple are allowed",
520 		"	     --bpf-action <program>: load and execute BPF program when latency threshold is exceeded",
521 		NULL,
522 	};
523 
524 	common_usage("timerlat", "top", "a per-cpu summary of the timer latency",
525 		     msg_start, msg_opts);
526 }
527 
528 /*
529  * timerlat_top_parse_args - allocs, parse and fill the cmd line parameters
530  */
531 static struct common_params
532 *timerlat_top_parse_args(int argc, char **argv)
533 {
534 	struct timerlat_params *params;
535 	long long auto_thresh;
536 	int retval;
537 	int c;
538 	char *trace_output = NULL;
539 
540 	params = calloc(1, sizeof(*params));
541 	if (!params)
542 		exit(1);
543 
544 	actions_init(&params->common.threshold_actions);
545 	actions_init(&params->common.end_actions);
546 
547 	/* disabled by default */
548 	params->dma_latency = -1;
549 
550 	/* disabled by default */
551 	params->deepest_idle_state = -2;
552 
553 	/* display data in microseconds */
554 	params->common.output_divisor = 1000;
555 
556 	/* default to BPF mode */
557 	params->mode = TRACING_MODE_BPF;
558 
559 	while (1) {
560 		static struct option long_options[] = {
561 			{"auto",		required_argument,	0, 'a'},
562 			{"help",		no_argument,		0, 'h'},
563 			{"irq",			required_argument,	0, 'i'},
564 			{"nano",		no_argument,		0, 'n'},
565 			{"period",		required_argument,	0, 'p'},
566 			{"quiet",		no_argument,		0, 'q'},
567 			{"stack",		required_argument,	0, 's'},
568 			{"thread",		required_argument,	0, 'T'},
569 			{"trace",		optional_argument,	0, 't'},
570 			{"user-threads",	no_argument,		0, 'u'},
571 			{"kernel-threads",	no_argument,		0, 'k'},
572 			{"user-load",		no_argument,		0, 'U'},
573 			{"trigger",		required_argument,	0, '0'},
574 			{"filter",		required_argument,	0, '1'},
575 			{"dma-latency",		required_argument,	0, '2'},
576 			{"no-aa",		no_argument,		0, '3'},
577 			{"dump-tasks",		no_argument,		0, '4'},
578 			{"aa-only",		required_argument,	0, '5'},
579 			{"warm-up",		required_argument,	0, '6'},
580 			{"trace-buffer-size",	required_argument,	0, '7'},
581 			{"deepest-idle-state",	required_argument,	0, '8'},
582 			{"on-threshold",	required_argument,	0, '9'},
583 			{"on-end",		required_argument,	0, '\1'},
584 			{"bpf-action",		required_argument,	0, '\2'},
585 			{0, 0, 0, 0}
586 		};
587 
588 		if (common_parse_options(argc, argv, &params->common))
589 			continue;
590 
591 		c = getopt_long(argc, argv, "a:hi:knp:qs:t::T:uU0:1:2:345:6:7:",
592 				 long_options, NULL);
593 
594 		/* detect the end of the options. */
595 		if (c == -1)
596 			break;
597 
598 		switch (c) {
599 		case 'a':
600 			auto_thresh = get_llong_from_str(optarg);
601 
602 			/* set thread stop to auto_thresh */
603 			params->common.stop_total_us = auto_thresh;
604 			params->common.stop_us = auto_thresh;
605 
606 			/* get stack trace */
607 			params->print_stack = auto_thresh;
608 
609 			/* set trace */
610 			if (!trace_output)
611 				trace_output = "timerlat_trace.txt";
612 
613 			break;
614 		case '5':
615 			/* it is here because it is similar to -a */
616 			auto_thresh = get_llong_from_str(optarg);
617 
618 			/* set thread stop to auto_thresh */
619 			params->common.stop_total_us = auto_thresh;
620 			params->common.stop_us = auto_thresh;
621 
622 			/* get stack trace */
623 			params->print_stack = auto_thresh;
624 
625 			/* set aa_only to avoid parsing the trace */
626 			params->common.aa_only = 1;
627 			break;
628 		case 'h':
629 		case '?':
630 			timerlat_top_usage();
631 			break;
632 		case 'i':
633 			params->common.stop_us = get_llong_from_str(optarg);
634 			break;
635 		case 'k':
636 			params->common.kernel_workload = true;
637 			break;
638 		case 'n':
639 			params->common.output_divisor = 1;
640 			break;
641 		case 'p':
642 			params->timerlat_period_us = get_llong_from_str(optarg);
643 			if (params->timerlat_period_us > 1000000)
644 				fatal("Period longer than 1 s");
645 			break;
646 		case 'q':
647 			params->common.quiet = 1;
648 			break;
649 		case 's':
650 			params->print_stack = get_llong_from_str(optarg);
651 			break;
652 		case 'T':
653 			params->common.stop_total_us = get_llong_from_str(optarg);
654 			break;
655 		case 't':
656 			trace_output = parse_optional_arg(argc, argv);
657 			if (!trace_output)
658 				trace_output = "timerlat_trace.txt";
659 			break;
660 		case 'u':
661 			params->common.user_workload = true;
662 			/* fallback: -u implies -U */
663 		case 'U':
664 			params->common.user_data = true;
665 			break;
666 		case '0': /* trigger */
667 			if (params->common.events) {
668 				retval = trace_event_add_trigger(params->common.events, optarg);
669 				if (retval)
670 					fatal("Error adding trigger %s", optarg);
671 			} else {
672 				fatal("--trigger requires a previous -e");
673 			}
674 			break;
675 		case '1': /* filter */
676 			if (params->common.events) {
677 				retval = trace_event_add_filter(params->common.events, optarg);
678 				if (retval)
679 					fatal("Error adding filter %s", optarg);
680 			} else {
681 				fatal("--filter requires a previous -e");
682 			}
683 			break;
684 		case '2': /* dma-latency */
685 			params->dma_latency = get_llong_from_str(optarg);
686 			if (params->dma_latency < 0 || params->dma_latency > 10000)
687 				fatal("--dma-latency needs to be >= 0 and < 10000");
688 			break;
689 		case '3': /* no-aa */
690 			params->no_aa = 1;
691 			break;
692 		case '4':
693 			params->dump_tasks = 1;
694 			break;
695 		case '6':
696 			params->common.warmup = get_llong_from_str(optarg);
697 			break;
698 		case '7':
699 			params->common.buffer_size = get_llong_from_str(optarg);
700 			break;
701 		case '8':
702 			params->deepest_idle_state = get_llong_from_str(optarg);
703 			break;
704 		case '9':
705 			retval = actions_parse(&params->common.threshold_actions, optarg,
706 					       "timerlat_trace.txt");
707 			if (retval)
708 				fatal("Invalid action %s", optarg);
709 			break;
710 		case '\1':
711 			retval = actions_parse(&params->common.end_actions, optarg,
712 					       "timerlat_trace.txt");
713 			if (retval)
714 				fatal("Invalid action %s", optarg);
715 			break;
716 		case '\2':
717 			params->bpf_action_program = optarg;
718 			break;
719 		default:
720 			fatal("Invalid option");
721 		}
722 	}
723 
724 	if (trace_output)
725 		actions_add_trace_output(&params->common.threshold_actions, trace_output);
726 
727 	if (geteuid())
728 		fatal("rtla needs root permission");
729 
730 	/*
731 	 * Auto analysis only happens if stop tracing, thus:
732 	 */
733 	if (!params->common.stop_us && !params->common.stop_total_us)
734 		params->no_aa = 1;
735 
736 	if (params->no_aa && params->common.aa_only)
737 		fatal("--no-aa and --aa-only are mutually exclusive!");
738 
739 	if (params->common.kernel_workload && params->common.user_workload)
740 		fatal("--kernel-threads and --user-threads are mutually exclusive!");
741 
742 	/*
743 	 * If auto-analysis or trace output is enabled, switch from BPF mode to
744 	 * mixed mode
745 	 */
746 	if (params->mode == TRACING_MODE_BPF &&
747 	    (params->common.threshold_actions.present[ACTION_TRACE_OUTPUT] ||
748 	     params->common.end_actions.present[ACTION_TRACE_OUTPUT] ||
749 	     !params->no_aa))
750 		params->mode = TRACING_MODE_MIXED;
751 
752 	return &params->common;
753 }
754 
755 /*
756  * timerlat_top_apply_config - apply the top configs to the initialized tool
757  */
758 static int
759 timerlat_top_apply_config(struct osnoise_tool *top)
760 {
761 	struct timerlat_params *params = to_timerlat_params(top->params);
762 	int retval;
763 
764 	retval = timerlat_apply_config(top, params);
765 	if (retval)
766 		goto out_err;
767 
768 	if (isatty(STDOUT_FILENO) && !params->common.quiet)
769 		params->common.pretty_output = 1;
770 
771 	return 0;
772 
773 out_err:
774 	return -1;
775 }
776 
777 /*
778  * timerlat_init_top - initialize a timerlat top tool with parameters
779  */
780 static struct osnoise_tool
781 *timerlat_init_top(struct common_params *params)
782 {
783 	struct osnoise_tool *top;
784 	int nr_cpus;
785 
786 	nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
787 
788 	top = osnoise_init_tool("timerlat_top");
789 	if (!top)
790 		return NULL;
791 
792 	top->data = timerlat_alloc_top(nr_cpus);
793 	if (!top->data)
794 		goto out_err;
795 
796 	tep_register_event_handler(top->trace.tep, -1, "ftrace", "timerlat",
797 				   timerlat_top_handler, top);
798 
799 	return top;
800 
801 out_err:
802 	osnoise_destroy_tool(top);
803 	return NULL;
804 }
805 
806 /*
807  * timerlat_top_bpf_main_loop - main loop to process events (BPF variant)
808  */
809 static int
810 timerlat_top_bpf_main_loop(struct osnoise_tool *tool)
811 {
812 	struct timerlat_params *params = to_timerlat_params(tool->params);
813 	int retval, wait_retval;
814 
815 	if (params->common.aa_only) {
816 		/* Auto-analysis only, just wait for stop tracing */
817 		timerlat_bpf_wait(-1);
818 		return 0;
819 	}
820 
821 	/* Pull and display data in a loop */
822 	while (!stop_tracing) {
823 		wait_retval = timerlat_bpf_wait(params->common.quiet ? -1 :
824 						params->common.sleep_time);
825 
826 		retval = timerlat_top_bpf_pull_data(tool);
827 		if (retval) {
828 			err_msg("Error pulling BPF data\n");
829 			return retval;
830 		}
831 
832 		if (!params->common.quiet)
833 			timerlat_print_stats(tool);
834 
835 		if (wait_retval != 0) {
836 			/* Stopping requested by tracer */
837 			actions_perform(&params->common.threshold_actions);
838 
839 			if (!params->common.threshold_actions.continue_flag)
840 				/* continue flag not set, break */
841 				break;
842 
843 			/* continue action reached, re-enable tracing */
844 			if (tool->record)
845 				trace_instance_start(&tool->record->trace);
846 			if (tool->aa)
847 				trace_instance_start(&tool->aa->trace);
848 			timerlat_bpf_restart_tracing();
849 		}
850 
851 		/* is there still any user-threads ? */
852 		if (params->common.user_workload) {
853 			if (params->common.user.stopped_running) {
854 				debug_msg("timerlat user space threads stopped!\n");
855 				break;
856 			}
857 		}
858 	}
859 
860 	return 0;
861 }
862 
863 static int timerlat_top_main_loop(struct osnoise_tool *tool)
864 {
865 	struct timerlat_params *params = to_timerlat_params(tool->params);
866 	int retval;
867 
868 	if (params->mode == TRACING_MODE_TRACEFS) {
869 		retval = top_main_loop(tool);
870 	} else {
871 		retval = timerlat_top_bpf_main_loop(tool);
872 		timerlat_bpf_detach();
873 	}
874 
875 	return retval;
876 }
877 
878 struct tool_ops timerlat_top_ops = {
879 	.tracer = "timerlat",
880 	.comm_prefix = "timerlat/",
881 	.parse_args = timerlat_top_parse_args,
882 	.init_tool = timerlat_init_top,
883 	.apply_config = timerlat_top_apply_config,
884 	.enable = timerlat_enable,
885 	.main = timerlat_top_main_loop,
886 	.print_stats = timerlat_print_stats,
887 	.analyze = timerlat_analyze,
888 	.free = timerlat_free_top_tool,
889 };
890