xref: /linux/tools/tracing/rtla/src/timerlat_top.c (revision b693b51e0829b96a5c43f45c3fba3d11f6f09d2f)
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 #include "common.h"
21 
22 struct timerlat_top_cpu {
23 	unsigned long long	irq_count;
24 	unsigned long long	thread_count;
25 	unsigned long long	user_count;
26 
27 	unsigned long long	cur_irq;
28 	unsigned long long	min_irq;
29 	unsigned long long	sum_irq;
30 	unsigned long long	max_irq;
31 
32 	unsigned long long	cur_thread;
33 	unsigned long long	min_thread;
34 	unsigned long long	sum_thread;
35 	unsigned long long	max_thread;
36 
37 	unsigned long long	cur_user;
38 	unsigned long long	min_user;
39 	unsigned long long	sum_user;
40 	unsigned long long	max_user;
41 };
42 
43 struct timerlat_top_data {
44 	struct timerlat_top_cpu	*cpu_data;
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(void)
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 	/* one set of histograms per CPU */
75 	data->cpu_data = calloc(1, sizeof(*data->cpu_data) * nr_cpus);
76 	if (!data->cpu_data)
77 		goto cleanup;
78 
79 	/* set the min to max */
80 	for (cpu = 0; cpu < nr_cpus; cpu++) {
81 		data->cpu_data[cpu].min_irq = ~0;
82 		data->cpu_data[cpu].min_thread = ~0;
83 		data->cpu_data[cpu].min_user = ~0;
84 	}
85 
86 	return data;
87 
88 cleanup:
89 	timerlat_free_top(data);
90 	return NULL;
91 }
92 
93 static void
94 timerlat_top_reset_sum(struct timerlat_top_cpu *summary)
95 {
96 	memset(summary, 0, sizeof(*summary));
97 	summary->min_irq = ~0;
98 	summary->min_thread = ~0;
99 	summary->min_user = ~0;
100 }
101 
102 static void
103 timerlat_top_update_sum(struct osnoise_tool *tool, int cpu, struct timerlat_top_cpu *sum)
104 {
105 	struct timerlat_top_data *data = tool->data;
106 	struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
107 
108 	sum->irq_count += cpu_data->irq_count;
109 	update_min(&sum->min_irq, &cpu_data->min_irq);
110 	update_sum(&sum->sum_irq, &cpu_data->sum_irq);
111 	update_max(&sum->max_irq, &cpu_data->max_irq);
112 
113 	sum->thread_count += cpu_data->thread_count;
114 	update_min(&sum->min_thread, &cpu_data->min_thread);
115 	update_sum(&sum->sum_thread, &cpu_data->sum_thread);
116 	update_max(&sum->max_thread, &cpu_data->max_thread);
117 
118 	sum->user_count += cpu_data->user_count;
119 	update_min(&sum->min_user, &cpu_data->min_user);
120 	update_sum(&sum->sum_user, &cpu_data->sum_user);
121 	update_max(&sum->max_user, &cpu_data->max_user);
122 }
123 
124 /*
125  * timerlat_hist_update - record a new timerlat occurent on cpu, updating data
126  */
127 static void
128 timerlat_top_update(struct osnoise_tool *tool, int cpu,
129 		    unsigned long long thread,
130 		    unsigned long long latency)
131 {
132 	struct timerlat_params *params = to_timerlat_params(tool->params);
133 	struct timerlat_top_data *data = tool->data;
134 	struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
135 
136 	if (params->common.output_divisor)
137 		latency = latency / params->common.output_divisor;
138 
139 	if (!thread) {
140 		cpu_data->irq_count++;
141 		cpu_data->cur_irq = latency;
142 		update_min(&cpu_data->min_irq, &latency);
143 		update_sum(&cpu_data->sum_irq, &latency);
144 		update_max(&cpu_data->max_irq, &latency);
145 	} else if (thread == 1) {
146 		cpu_data->thread_count++;
147 		cpu_data->cur_thread = latency;
148 		update_min(&cpu_data->min_thread, &latency);
149 		update_sum(&cpu_data->sum_thread, &latency);
150 		update_max(&cpu_data->max_thread, &latency);
151 	} else {
152 		cpu_data->user_count++;
153 		cpu_data->cur_user = latency;
154 		update_min(&cpu_data->min_user, &latency);
155 		update_sum(&cpu_data->sum_user, &latency);
156 		update_max(&cpu_data->max_user, &latency);
157 	}
158 }
159 
160 /*
161  * timerlat_top_handler - this is the handler for timerlat tracer events
162  */
163 static int
164 timerlat_top_handler(struct trace_seq *s, struct tep_record *record,
165 		     struct tep_event *event, void *context)
166 {
167 	struct trace_instance *trace = context;
168 	unsigned long long latency, thread;
169 	struct osnoise_tool *top;
170 	int cpu = record->cpu;
171 
172 	top = container_of(trace, struct osnoise_tool, trace);
173 
174 	if (!top->params->aa_only) {
175 		tep_get_field_val(s, event, "context", record, &thread, 1);
176 		tep_get_field_val(s, event, "timer_latency", record, &latency, 1);
177 
178 		timerlat_top_update(top, cpu, thread, latency);
179 	}
180 
181 	return 0;
182 }
183 
184 /*
185  * timerlat_top_bpf_pull_data - copy data from BPF maps into userspace
186  */
187 static int timerlat_top_bpf_pull_data(struct osnoise_tool *tool)
188 {
189 	struct timerlat_top_data *data = tool->data;
190 	int i, err;
191 	long long value_irq[nr_cpus],
192 		  value_thread[nr_cpus],
193 		  value_user[nr_cpus];
194 
195 	/* Pull summary */
196 	err = timerlat_bpf_get_summary_value(SUMMARY_CURRENT,
197 					     value_irq, value_thread, value_user);
198 	if (err)
199 		return err;
200 	for (i = 0; i < nr_cpus; i++) {
201 		data->cpu_data[i].cur_irq = value_irq[i];
202 		data->cpu_data[i].cur_thread = value_thread[i];
203 		data->cpu_data[i].cur_user = value_user[i];
204 	}
205 
206 	err = timerlat_bpf_get_summary_value(SUMMARY_COUNT,
207 					     value_irq, value_thread, value_user);
208 	if (err)
209 		return err;
210 	for (i = 0; i < nr_cpus; i++) {
211 		data->cpu_data[i].irq_count = value_irq[i];
212 		data->cpu_data[i].thread_count = value_thread[i];
213 		data->cpu_data[i].user_count = value_user[i];
214 	}
215 
216 	err = timerlat_bpf_get_summary_value(SUMMARY_MIN,
217 					     value_irq, value_thread, value_user);
218 	if (err)
219 		return err;
220 	for (i = 0; i < nr_cpus; i++) {
221 		data->cpu_data[i].min_irq = value_irq[i];
222 		data->cpu_data[i].min_thread = value_thread[i];
223 		data->cpu_data[i].min_user = value_user[i];
224 	}
225 
226 	err = timerlat_bpf_get_summary_value(SUMMARY_MAX,
227 					     value_irq, value_thread, value_user);
228 	if (err)
229 		return err;
230 	for (i = 0; i < nr_cpus; i++) {
231 		data->cpu_data[i].max_irq = value_irq[i];
232 		data->cpu_data[i].max_thread = value_thread[i];
233 		data->cpu_data[i].max_user = value_user[i];
234 	}
235 
236 	err = timerlat_bpf_get_summary_value(SUMMARY_SUM,
237 					     value_irq, value_thread, value_user);
238 	if (err)
239 		return err;
240 	for (i = 0; i < nr_cpus; i++) {
241 		data->cpu_data[i].sum_irq = value_irq[i];
242 		data->cpu_data[i].sum_thread = value_thread[i];
243 		data->cpu_data[i].sum_user = value_user[i];
244 	}
245 
246 	return 0;
247 }
248 
249 /*
250  * timerlat_top_header - print the header of the tool output
251  */
252 static void timerlat_top_header(struct timerlat_params *params, struct osnoise_tool *top)
253 {
254 	struct trace_seq *s = top->trace.seq;
255 	bool pretty = params->common.pretty_output;
256 	char duration[26];
257 
258 	get_duration(top->start_time, duration, sizeof(duration));
259 
260 	if (pretty)
261 		trace_seq_printf(s, "\033[2;37;40m");
262 
263 	trace_seq_printf(s, "                                     Timer Latency                                              ");
264 	if (params->common.user_data)
265 		trace_seq_printf(s, "                                         ");
266 
267 	if (pretty)
268 		trace_seq_printf(s, "\033[0;0;0m");
269 	trace_seq_printf(s, "\n");
270 
271 	trace_seq_printf(s, "%-6s   |          IRQ Timer Latency (%s)        |         Thread Timer Latency (%s)", duration,
272 			params->common.output_divisor == 1 ? "ns" : "us",
273 			params->common.output_divisor == 1 ? "ns" : "us");
274 
275 	if (params->common.user_data) {
276 		trace_seq_printf(s, "      |    Ret user Timer Latency (%s)",
277 				params->common.output_divisor == 1 ? "ns" : "us");
278 	}
279 
280 	trace_seq_printf(s, "\n");
281 	if (pretty)
282 		trace_seq_printf(s, "\033[2;30;47m");
283 
284 	trace_seq_printf(s, "CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max");
285 	if (params->common.user_data)
286 		trace_seq_printf(s, " |      cur       min       avg       max");
287 
288 	if (pretty)
289 		trace_seq_printf(s, "\033[0;0;0m");
290 	trace_seq_printf(s, "\n");
291 }
292 
293 static const char *no_value = "        -";
294 
295 /*
296  * timerlat_top_print - prints the output of a given CPU
297  */
298 static void timerlat_top_print(struct osnoise_tool *top, int cpu)
299 {
300 	struct timerlat_params *params = to_timerlat_params(top->params);
301 	struct timerlat_top_data *data = top->data;
302 	struct timerlat_top_cpu *cpu_data = &data->cpu_data[cpu];
303 	struct trace_seq *s = top->trace.seq;
304 
305 	/*
306 	 * Skip if no data is available: is this cpu offline?
307 	 */
308 	if (!cpu_data->irq_count && !cpu_data->thread_count)
309 		return;
310 
311 	/*
312 	 * Unless trace is being lost, IRQ counter is always the max.
313 	 */
314 	trace_seq_printf(s, "%3d #%-9llu |", cpu, cpu_data->irq_count);
315 
316 	if (!cpu_data->irq_count) {
317 		trace_seq_printf(s, "%s %s %s %s |", no_value, no_value, no_value, no_value);
318 	} else {
319 		trace_seq_printf(s, "%9llu ", cpu_data->cur_irq);
320 		trace_seq_printf(s, "%9llu ", cpu_data->min_irq);
321 		trace_seq_printf(s, "%9llu ", cpu_data->sum_irq / cpu_data->irq_count);
322 		trace_seq_printf(s, "%9llu |", cpu_data->max_irq);
323 	}
324 
325 	if (!cpu_data->thread_count) {
326 		trace_seq_printf(s, "%s %s %s %s", no_value, no_value, no_value, no_value);
327 	} else {
328 		trace_seq_printf(s, "%9llu ", cpu_data->cur_thread);
329 		trace_seq_printf(s, "%9llu ", cpu_data->min_thread);
330 		trace_seq_printf(s, "%9llu ",
331 				cpu_data->sum_thread / cpu_data->thread_count);
332 		trace_seq_printf(s, "%9llu", cpu_data->max_thread);
333 	}
334 
335 	if (!params->common.user_data) {
336 		trace_seq_printf(s, "\n");
337 		return;
338 	}
339 
340 	trace_seq_printf(s, " |");
341 
342 	if (!cpu_data->user_count) {
343 		trace_seq_printf(s, "%s %s %s %s\n", no_value, no_value, no_value, no_value);
344 	} else {
345 		trace_seq_printf(s, "%9llu ", cpu_data->cur_user);
346 		trace_seq_printf(s, "%9llu ", cpu_data->min_user);
347 		trace_seq_printf(s, "%9llu ",
348 				cpu_data->sum_user / cpu_data->user_count);
349 		trace_seq_printf(s, "%9llu\n", cpu_data->max_user);
350 	}
351 }
352 
353 /*
354  * timerlat_top_print_sum - prints the summary output
355  */
356 static void
357 timerlat_top_print_sum(struct osnoise_tool *top, struct timerlat_top_cpu *summary)
358 {
359 	const char *split = "----------------------------------------";
360 	struct timerlat_params *params = to_timerlat_params(top->params);
361 	unsigned long long count = summary->irq_count;
362 	struct trace_seq *s = top->trace.seq;
363 	int e = 0;
364 
365 	/*
366 	 * Skip if no data is available: is this cpu offline?
367 	 */
368 	if (!summary->irq_count && !summary->thread_count)
369 		return;
370 
371 	while (count > 999999) {
372 		e++;
373 		count /= 10;
374 	}
375 
376 	trace_seq_printf(s, "%.*s|%.*s|%.*s", 15, split, 40, split, 39, split);
377 	if (params->common.user_data)
378 		trace_seq_printf(s, "-|%.*s", 39, split);
379 	trace_seq_printf(s, "\n");
380 
381 	trace_seq_printf(s, "ALL #%-6llu e%d |", count, e);
382 
383 	if (!summary->irq_count) {
384 		trace_seq_printf(s, "          %s %s %s |", no_value, no_value, no_value);
385 	} else {
386 		trace_seq_printf(s, "          ");
387 		trace_seq_printf(s, "%9llu ", summary->min_irq);
388 		trace_seq_printf(s, "%9llu ", summary->sum_irq / summary->irq_count);
389 		trace_seq_printf(s, "%9llu |", summary->max_irq);
390 	}
391 
392 	if (!summary->thread_count) {
393 		trace_seq_printf(s, "%s %s %s %s", no_value, no_value, no_value, no_value);
394 	} else {
395 		trace_seq_printf(s, "          ");
396 		trace_seq_printf(s, "%9llu ", summary->min_thread);
397 		trace_seq_printf(s, "%9llu ",
398 				summary->sum_thread / summary->thread_count);
399 		trace_seq_printf(s, "%9llu", summary->max_thread);
400 	}
401 
402 	if (!params->common.user_data) {
403 		trace_seq_printf(s, "\n");
404 		return;
405 	}
406 
407 	trace_seq_printf(s, " |");
408 
409 	if (!summary->user_count) {
410 		trace_seq_printf(s, "          %s %s %s |", no_value, no_value, no_value);
411 	} else {
412 		trace_seq_printf(s, "          ");
413 		trace_seq_printf(s, "%9llu ", summary->min_user);
414 		trace_seq_printf(s, "%9llu ",
415 				summary->sum_user / summary->user_count);
416 		trace_seq_printf(s, "%9llu\n", summary->max_user);
417 	}
418 }
419 
420 /*
421  * clear_terminal - clears the output terminal
422  */
423 static void clear_terminal(struct trace_seq *seq)
424 {
425 	if (!config_debug)
426 		trace_seq_printf(seq, "\033c");
427 }
428 
429 /*
430  * timerlat_print_stats - print data for all cpus
431  */
432 static void
433 timerlat_print_stats(struct osnoise_tool *top)
434 {
435 	struct timerlat_params *params = to_timerlat_params(top->params);
436 	struct trace_instance *trace = &top->trace;
437 	struct timerlat_top_cpu summary;
438 	int i;
439 
440 	if (params->common.aa_only)
441 		return;
442 
443 	if (!params->common.quiet)
444 		clear_terminal(trace->seq);
445 
446 	timerlat_top_reset_sum(&summary);
447 
448 	timerlat_top_header(params, top);
449 
450 	for_each_monitored_cpu(i, &params->common) {
451 		timerlat_top_print(top, i);
452 		timerlat_top_update_sum(top, i, &summary);
453 	}
454 
455 	timerlat_top_print_sum(top, &summary);
456 
457 	trace_seq_do_printf(trace->seq);
458 	trace_seq_reset(trace->seq);
459 	osnoise_report_missed_events(top);
460 }
461 
462 /*
463  * timerlat_top_usage - prints timerlat top usage message
464  */
465 static void timerlat_top_usage(void)
466 {
467 	static const char *const msg_start[] = {
468 		"[-q] [-a us] [-d s] [-D] [-n] [-p us] [-i us] [-T us] [-s us] \\",
469 		"	  [[-t [file]] [-e sys[:event]] [--filter <filter>] [--trigger <trigger>] [-c cpu-list] [-H cpu-list]\\",
470 		"	  [-P priority] [--dma-latency us] [--aa-only us] [-C [cgroup_name]] [-u|-k] [--warm-up s] [--deepest-idle-state n]",
471 		NULL,
472 	};
473 
474 	static const char *const msg_opts[] = {
475 		"	  -a/--auto: set automatic trace mode, stopping the session if argument in us latency is hit",
476 		"	     --aa-only us: stop if <us> latency is hit, only printing the auto analysis (reduces CPU usage)",
477 		"	  -p/--period us: timerlat period in us",
478 		"	  -i/--irq us: stop trace if the irq latency is higher than the argument in us",
479 		"	  -T/--thread us: stop trace if the thread latency is higher than the argument in us",
480 		"	  -s/--stack us: save the stack trace at the IRQ if a thread latency is higher than the argument in us",
481 		"	  -c/--cpus cpus: run the tracer only on the given cpus",
482 		"	  -H/--house-keeping cpus: run rtla control threads only on the given cpus",
483 		"	  -C/--cgroup [cgroup_name]: set cgroup, if no cgroup_name is passed, the rtla's cgroup will be inherited",
484 		"	  -d/--duration time[s|m|h|d]: duration of the session",
485 		"	  -D/--debug: print debug info",
486 		"	     --dump-tasks: prints the task running on all CPUs if stop conditions are met (depends on !--no-aa)",
487 		"	  -t/--trace [file]: save the stopped trace to [file|timerlat_trace.txt]",
488 		"	  -e/--event <sys:event>: enable the <sys:event> in the trace instance, multiple -e are allowed",
489 		"	     --filter <command>: enable a trace event filter to the previous -e event",
490 		"	     --trigger <command>: enable a trace event trigger to the previous -e event",
491 		"	  -n/--nano: display data in nanoseconds",
492 		"	     --no-aa: disable auto-analysis, reducing rtla timerlat cpu usage",
493 		"	  -q/--quiet print only a summary at the end",
494 		"	     --dma-latency us: set /dev/cpu_dma_latency latency <us> to reduce exit from idle latency",
495 		"	  -P/--priority o:prio|r:prio|f:prio|d:runtime:period : set scheduling parameters",
496 		"		o:prio - use SCHED_OTHER with prio",
497 		"		r:prio - use SCHED_RR with prio",
498 		"		f:prio - use SCHED_FIFO with prio",
499 		"		d:runtime[us|ms|s]:period[us|ms|s] - use SCHED_DEADLINE with runtime and period",
500 		"						       in nanoseconds",
501 		"	  -u/--user-threads: use rtla user-space threads instead of kernel-space timerlat threads",
502 		"	  -k/--kernel-threads: use timerlat kernel-space threads instead of rtla user-space threads",
503 		"	  -U/--user-load: enable timerlat for user-defined user-space workload",
504 		"	     --warm-up s: let the workload run for s seconds before collecting data",
505 		"	     --trace-buffer-size kB: set the per-cpu trace buffer size in kB",
506 		"	     --deepest-idle-state n: only go down to idle state n on cpus used by timerlat to reduce exit from idle latency",
507 		"	     --on-threshold <action>: define action to be executed at latency threshold, multiple are allowed",
508 		"	     --on-end: define action to be executed at measurement end, multiple are allowed",
509 		"	     --bpf-action <program>: load and execute BPF program when latency threshold is exceeded",
510 		"	     --stack-format <format>: set the stack format (truncate, skip, full)",
511 		NULL,
512 	};
513 
514 	common_usage("timerlat", "top", "a per-cpu summary of the timer latency",
515 		     msg_start, msg_opts);
516 }
517 
518 /*
519  * timerlat_top_parse_args - allocs, parse and fill the cmd line parameters
520  */
521 static struct common_params
522 *timerlat_top_parse_args(int argc, char **argv)
523 {
524 	struct timerlat_params *params;
525 	long long auto_thresh;
526 	int retval;
527 	int c;
528 	char *trace_output = NULL;
529 
530 	params = calloc_fatal(1, sizeof(*params));
531 
532 	actions_init(&params->common.threshold_actions);
533 	actions_init(&params->common.end_actions);
534 
535 	/* disabled by default */
536 	params->dma_latency = -1;
537 
538 	/* disabled by default */
539 	params->deepest_idle_state = -2;
540 
541 	/* display data in microseconds */
542 	params->common.output_divisor = 1000;
543 
544 	/* default to BPF mode */
545 	params->mode = TRACING_MODE_BPF;
546 
547 	/* default to truncate stack format */
548 	params->stack_format = STACK_FORMAT_TRUNCATE;
549 
550 	while (1) {
551 		static struct option long_options[] = {
552 			COMMON_OPTIONS,
553 			{"auto",		required_argument,	0, 'a'},
554 			{"help",		no_argument,		0, 'h'},
555 			{"irq",			required_argument,	0, 'i'},
556 			{"nano",		no_argument,		0, 'n'},
557 			{"period",		required_argument,	0, 'p'},
558 			{"quiet",		no_argument,		0, 'q'},
559 			{"stack",		required_argument,	0, 's'},
560 			{"thread",		required_argument,	0, 'T'},
561 			{"trace",		optional_argument,	0, 't'},
562 			{"user-threads",	no_argument,		0, 'u'},
563 			{"kernel-threads",	no_argument,		0, 'k'},
564 			{"user-load",		no_argument,		0, 'U'},
565 			{"trigger",		required_argument,	0, '0'},
566 			{"filter",		required_argument,	0, '1'},
567 			{"dma-latency",		required_argument,	0, '2'},
568 			{"no-aa",		no_argument,		0, '3'},
569 			{"dump-tasks",		no_argument,		0, '4'},
570 			{"aa-only",		required_argument,	0, '5'},
571 			{"warm-up",		required_argument,	0, '6'},
572 			{"trace-buffer-size",	required_argument,	0, '7'},
573 			{"deepest-idle-state",	required_argument,	0, '8'},
574 			{"on-threshold",	required_argument,	0, '9'},
575 			{"on-end",		required_argument,	0, '\1'},
576 			{"bpf-action",		required_argument,	0, '\2'},
577 			{"stack-format",	required_argument,	0, '\3'},
578 			{0, 0, 0, 0}
579 		};
580 
581 		c = getopt_auto(argc, argv, long_options);
582 
583 		if (set_common_option(c, argc, argv, &params->common))
584 			continue;
585 
586 		/* detect the end of the options. */
587 		if (c == -1)
588 			break;
589 
590 		switch (c) {
591 		case 'a':
592 			auto_thresh = get_llong_from_str(optarg);
593 
594 			/* set thread stop to auto_thresh */
595 			params->common.stop_total_us = auto_thresh;
596 			params->common.stop_us = auto_thresh;
597 
598 			/* get stack trace */
599 			params->print_stack = auto_thresh;
600 
601 			/* set trace */
602 			if (!trace_output)
603 				trace_output = "timerlat_trace.txt";
604 
605 			break;
606 		case '5':
607 			/* it is here because it is similar to -a */
608 			auto_thresh = get_llong_from_str(optarg);
609 
610 			/* set thread stop to auto_thresh */
611 			params->common.stop_total_us = auto_thresh;
612 			params->common.stop_us = auto_thresh;
613 
614 			/* get stack trace */
615 			params->print_stack = auto_thresh;
616 
617 			/* set aa_only to avoid parsing the trace */
618 			params->common.aa_only = 1;
619 			break;
620 		case 'h':
621 		case '?':
622 			timerlat_top_usage();
623 			break;
624 		case 'i':
625 			params->common.stop_us = get_llong_from_str(optarg);
626 			break;
627 		case 'k':
628 			params->common.kernel_workload = true;
629 			break;
630 		case 'n':
631 			params->common.output_divisor = 1;
632 			break;
633 		case 'p':
634 			params->timerlat_period_us = get_llong_from_str(optarg);
635 			if (params->timerlat_period_us > 1000000)
636 				fatal("Period longer than 1 s");
637 			break;
638 		case 'q':
639 			params->common.quiet = 1;
640 			break;
641 		case 's':
642 			params->print_stack = get_llong_from_str(optarg);
643 			break;
644 		case 'T':
645 			params->common.stop_total_us = get_llong_from_str(optarg);
646 			break;
647 		case 't':
648 			trace_output = parse_optional_arg(argc, argv);
649 			if (!trace_output)
650 				trace_output = "timerlat_trace.txt";
651 			break;
652 		case 'u':
653 			params->common.user_workload = true;
654 			/* fallback: -u implies -U */
655 		case 'U':
656 			params->common.user_data = true;
657 			break;
658 		case '0': /* trigger */
659 			if (params->common.events)
660 				trace_event_add_trigger(params->common.events, optarg);
661 			else
662 				fatal("--trigger requires a previous -e");
663 			break;
664 		case '1': /* filter */
665 			if (params->common.events)
666 				trace_event_add_filter(params->common.events, optarg);
667 			else
668 				fatal("--filter requires a previous -e");
669 			break;
670 		case '2': /* dma-latency */
671 			params->dma_latency = get_llong_from_str(optarg);
672 			if (params->dma_latency < 0 || params->dma_latency > 10000)
673 				fatal("--dma-latency needs to be >= 0 and < 10000");
674 			break;
675 		case '3': /* no-aa */
676 			params->no_aa = 1;
677 			break;
678 		case '4':
679 			params->dump_tasks = 1;
680 			break;
681 		case '6':
682 			params->common.warmup = get_llong_from_str(optarg);
683 			break;
684 		case '7':
685 			params->common.buffer_size = get_llong_from_str(optarg);
686 			break;
687 		case '8':
688 			params->deepest_idle_state = get_llong_from_str(optarg);
689 			break;
690 		case '9':
691 			retval = actions_parse(&params->common.threshold_actions, optarg,
692 					       "timerlat_trace.txt");
693 			if (retval)
694 				fatal("Invalid action %s", optarg);
695 			break;
696 		case '\1':
697 			retval = actions_parse(&params->common.end_actions, optarg,
698 					       "timerlat_trace.txt");
699 			if (retval)
700 				fatal("Invalid action %s", optarg);
701 			break;
702 		case '\2':
703 			params->bpf_action_program = optarg;
704 			break;
705 		case '\3':
706 			params->stack_format = parse_stack_format(optarg);
707 			if (params->stack_format == -1)
708 				fatal("Invalid --stack-format option");
709 			break;
710 		default:
711 			fatal("Invalid option");
712 		}
713 	}
714 
715 	if (trace_output)
716 		actions_add_trace_output(&params->common.threshold_actions, trace_output);
717 
718 	if (geteuid())
719 		fatal("rtla needs root permission");
720 
721 	/*
722 	 * Auto analysis only happens if stop tracing, thus:
723 	 */
724 	if (!params->common.stop_us && !params->common.stop_total_us)
725 		params->no_aa = 1;
726 
727 	if (params->no_aa && params->common.aa_only)
728 		fatal("--no-aa and --aa-only are mutually exclusive!");
729 
730 	if (params->common.kernel_workload && params->common.user_workload)
731 		fatal("--kernel-threads and --user-threads are mutually exclusive!");
732 
733 	/*
734 	 * If auto-analysis or trace output is enabled, switch from BPF mode to
735 	 * mixed mode
736 	 */
737 	if (params->mode == TRACING_MODE_BPF &&
738 	    (params->common.threshold_actions.present[ACTION_TRACE_OUTPUT] ||
739 	     params->common.end_actions.present[ACTION_TRACE_OUTPUT] ||
740 	     !params->no_aa))
741 		params->mode = TRACING_MODE_MIXED;
742 
743 	return &params->common;
744 }
745 
746 /*
747  * timerlat_top_apply_config - apply the top configs to the initialized tool
748  */
749 static int
750 timerlat_top_apply_config(struct osnoise_tool *top)
751 {
752 	struct timerlat_params *params = to_timerlat_params(top->params);
753 	int retval;
754 
755 	retval = timerlat_apply_config(top, params);
756 	if (retval)
757 		goto out_err;
758 
759 	if (isatty(STDOUT_FILENO) && !params->common.quiet)
760 		params->common.pretty_output = 1;
761 
762 	return 0;
763 
764 out_err:
765 	return -1;
766 }
767 
768 /*
769  * timerlat_init_top - initialize a timerlat top tool with parameters
770  */
771 static struct osnoise_tool
772 *timerlat_init_top(struct common_params *params)
773 {
774 	struct osnoise_tool *top;
775 
776 	top = osnoise_init_tool("timerlat_top");
777 	if (!top)
778 		return NULL;
779 
780 	top->data = timerlat_alloc_top();
781 	if (!top->data)
782 		goto out_err;
783 
784 	tep_register_event_handler(top->trace.tep, -1, "ftrace", "timerlat",
785 				   timerlat_top_handler, top);
786 
787 	return top;
788 
789 out_err:
790 	osnoise_destroy_tool(top);
791 	return NULL;
792 }
793 
794 /*
795  * timerlat_top_bpf_main_loop - main loop to process events (BPF variant)
796  */
797 static int
798 timerlat_top_bpf_main_loop(struct osnoise_tool *tool)
799 {
800 	const struct common_params *params = tool->params;
801 	int retval, wait_retval;
802 
803 	if (params->aa_only) {
804 		/* Auto-analysis only, just wait for stop tracing */
805 		timerlat_bpf_wait(-1);
806 		return 0;
807 	}
808 
809 	/* Pull and display data in a loop */
810 	while (!stop_tracing) {
811 		wait_retval = timerlat_bpf_wait(params->quiet ? -1 :
812 						params->sleep_time);
813 
814 		retval = timerlat_top_bpf_pull_data(tool);
815 		if (retval) {
816 			err_msg("Error pulling BPF data\n");
817 			return retval;
818 		}
819 
820 		if (!params->quiet)
821 			timerlat_print_stats(tool);
822 
823 		if (wait_retval != 0) {
824 			/* Stopping requested by tracer */
825 			retval = common_threshold_handler(tool);
826 			if (retval)
827 				return retval;
828 
829 			if (!should_continue_tracing(tool->params))
830 				break;
831 
832 			if (timerlat_bpf_restart_tracing()) {
833 				err_msg("Error restarting BPF trace\n");
834 				return -1;
835 			}
836 		}
837 
838 		/* is there still any user-threads ? */
839 		if (params->user_workload) {
840 			if (params->user.stopped_running) {
841 				debug_msg("timerlat user space threads stopped!\n");
842 				break;
843 			}
844 		}
845 	}
846 
847 	return 0;
848 }
849 
850 static int timerlat_top_main_loop(struct osnoise_tool *tool)
851 {
852 	struct timerlat_params *params = to_timerlat_params(tool->params);
853 	int retval;
854 
855 	if (params->mode == TRACING_MODE_TRACEFS) {
856 		retval = top_main_loop(tool);
857 	} else {
858 		retval = timerlat_top_bpf_main_loop(tool);
859 		timerlat_bpf_detach();
860 	}
861 
862 	return retval;
863 }
864 
865 struct tool_ops timerlat_top_ops = {
866 	.tracer = "timerlat",
867 	.comm_prefix = "timerlat/",
868 	.parse_args = timerlat_top_parse_args,
869 	.init_tool = timerlat_init_top,
870 	.apply_config = timerlat_top_apply_config,
871 	.enable = timerlat_enable,
872 	.main = timerlat_top_main_loop,
873 	.print_stats = timerlat_print_stats,
874 	.analyze = timerlat_analyze,
875 	.free = timerlat_free_top_tool,
876 };
877