xref: /linux/tools/perf/builtin-ftrace.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * builtin-ftrace.c
4  *
5  * Copyright (c) 2013  LG Electronics,  Namhyung Kim <namhyung@kernel.org>
6  * Copyright (c) 2020  Changbin Du <changbin.du@gmail.com>, significant enhancement.
7  */
8 
9 #include "builtin.h"
10 
11 #include <errno.h>
12 #include <unistd.h>
13 #include <signal.h>
14 #include <stdlib.h>
15 #include <fcntl.h>
16 #include <inttypes.h>
17 #include <math.h>
18 #include <poll.h>
19 #include <ctype.h>
20 #include <linux/capability.h>
21 #include <linux/string.h>
22 
23 #include "debug.h"
24 #include <subcmd/pager.h>
25 #include <subcmd/parse-options.h>
26 #include <api/io.h>
27 #include <api/fs/tracing_path.h>
28 #include "evlist.h"
29 #include "target.h"
30 #include "cpumap.h"
31 #include "hashmap.h"
32 #include "thread_map.h"
33 #include "strfilter.h"
34 #include "util/cap.h"
35 #include "util/config.h"
36 #include "util/ftrace.h"
37 #include "util/stat.h"
38 #include "util/units.h"
39 #include "util/parse-sublevel-options.h"
40 
41 #define DEFAULT_TRACER  "function_graph"
42 
43 static volatile sig_atomic_t workload_exec_errno;
44 static volatile sig_atomic_t done;
45 
sig_handler(int sig __maybe_unused)46 static void sig_handler(int sig __maybe_unused)
47 {
48 	done = true;
49 }
50 
51 /*
52  * evlist__prepare_workload will send a SIGUSR1 if the fork fails, since
53  * we asked by setting its exec_error to the function below,
54  * ftrace__workload_exec_failed_signal.
55  *
56  * XXX We need to handle this more appropriately, emitting an error, etc.
57  */
ftrace__workload_exec_failed_signal(int signo __maybe_unused,siginfo_t * info __maybe_unused,void * ucontext __maybe_unused)58 static void ftrace__workload_exec_failed_signal(int signo __maybe_unused,
59 						siginfo_t *info __maybe_unused,
60 						void *ucontext __maybe_unused)
61 {
62 	workload_exec_errno = info->si_value.sival_int;
63 	done = true;
64 }
65 
check_ftrace_capable(void)66 static bool check_ftrace_capable(void)
67 {
68 	bool used_root;
69 
70 	if (perf_cap__capable(CAP_PERFMON, &used_root))
71 		return true;
72 
73 	if (!used_root && perf_cap__capable(CAP_SYS_ADMIN, &used_root))
74 		return true;
75 
76 	pr_err("ftrace only works for %s!\n",
77 		used_root ? "root"
78 			  : "users with the CAP_PERFMON or CAP_SYS_ADMIN capability"
79 		);
80 	return false;
81 }
82 
is_ftrace_supported(void)83 static bool is_ftrace_supported(void)
84 {
85 	char *file;
86 	bool supported = false;
87 
88 	file = get_tracing_file("set_ftrace_pid");
89 	if (!file) {
90 		pr_debug("cannot get tracing file set_ftrace_pid\n");
91 		return false;
92 	}
93 
94 	if (!access(file, F_OK))
95 		supported = true;
96 
97 	put_tracing_file(file);
98 	return supported;
99 }
100 
__write_tracing_file(const char * name,const char * val,bool append)101 static int __write_tracing_file(const char *name, const char *val, bool append)
102 {
103 	char *file;
104 	int fd, ret = -1;
105 	ssize_t size = strlen(val);
106 	int flags = O_WRONLY;
107 	char errbuf[512];
108 	char *val_copy;
109 
110 	file = get_tracing_file(name);
111 	if (!file) {
112 		pr_debug("cannot get tracing file: %s\n", name);
113 		return -1;
114 	}
115 
116 	if (append)
117 		flags |= O_APPEND;
118 	else
119 		flags |= O_TRUNC;
120 
121 	fd = open(file, flags);
122 	if (fd < 0) {
123 		pr_debug("cannot open tracing file: %s: %s\n",
124 			 name, str_error_r(errno, errbuf, sizeof(errbuf)));
125 		goto out;
126 	}
127 
128 	/*
129 	 * Copy the original value and append a '\n'. Without this,
130 	 * the kernel can hide possible errors.
131 	 */
132 	val_copy = strdup(val);
133 	if (!val_copy)
134 		goto out_close;
135 	val_copy[size] = '\n';
136 
137 	if (write(fd, val_copy, size + 1) == size + 1)
138 		ret = 0;
139 	else
140 		pr_debug("write '%s' to tracing/%s failed: %s\n",
141 			 val, name, str_error_r(errno, errbuf, sizeof(errbuf)));
142 
143 	free(val_copy);
144 out_close:
145 	close(fd);
146 out:
147 	put_tracing_file(file);
148 	return ret;
149 }
150 
write_tracing_file(const char * name,const char * val)151 static int write_tracing_file(const char *name, const char *val)
152 {
153 	return __write_tracing_file(name, val, false);
154 }
155 
append_tracing_file(const char * name,const char * val)156 static int append_tracing_file(const char *name, const char *val)
157 {
158 	return __write_tracing_file(name, val, true);
159 }
160 
read_tracing_file_to_stdout(const char * name)161 static int read_tracing_file_to_stdout(const char *name)
162 {
163 	char buf[4096];
164 	char *file;
165 	int fd;
166 	int ret = -1;
167 
168 	file = get_tracing_file(name);
169 	if (!file) {
170 		pr_debug("cannot get tracing file: %s\n", name);
171 		return -1;
172 	}
173 
174 	fd = open(file, O_RDONLY);
175 	if (fd < 0) {
176 		pr_debug("cannot open tracing file: %s: %s\n",
177 			 name, str_error_r(errno, buf, sizeof(buf)));
178 		goto out;
179 	}
180 
181 	/* read contents to stdout */
182 	while (true) {
183 		int n = read(fd, buf, sizeof(buf));
184 		if (n == 0)
185 			break;
186 		else if (n < 0)
187 			goto out_close;
188 
189 		if (fwrite(buf, n, 1, stdout) != 1)
190 			goto out_close;
191 	}
192 	ret = 0;
193 
194 out_close:
195 	close(fd);
196 out:
197 	put_tracing_file(file);
198 	return ret;
199 }
200 
read_tracing_file_by_line(const char * name,void (* cb)(char * str,void * arg),void * cb_arg)201 static int read_tracing_file_by_line(const char *name,
202 				     void (*cb)(char *str, void *arg),
203 				     void *cb_arg)
204 {
205 	char *line = NULL;
206 	size_t len = 0;
207 	char *file;
208 	FILE *fp;
209 
210 	file = get_tracing_file(name);
211 	if (!file) {
212 		pr_debug("cannot get tracing file: %s\n", name);
213 		return -1;
214 	}
215 
216 	fp = fopen(file, "r");
217 	if (fp == NULL) {
218 		pr_debug("cannot open tracing file: %s\n", name);
219 		put_tracing_file(file);
220 		return -1;
221 	}
222 
223 	while (getline(&line, &len, fp) != -1) {
224 		cb(line, cb_arg);
225 	}
226 
227 	if (line)
228 		free(line);
229 
230 	fclose(fp);
231 	put_tracing_file(file);
232 	return 0;
233 }
234 
write_tracing_file_int(const char * name,int value)235 static int write_tracing_file_int(const char *name, int value)
236 {
237 	char buf[16];
238 
239 	snprintf(buf, sizeof(buf), "%d", value);
240 	if (write_tracing_file(name, buf) < 0)
241 		return -1;
242 
243 	return 0;
244 }
245 
write_tracing_option_file(const char * name,const char * val)246 static int write_tracing_option_file(const char *name, const char *val)
247 {
248 	char *file;
249 	int ret;
250 
251 	if (asprintf(&file, "options/%s", name) < 0)
252 		return -1;
253 
254 	ret = __write_tracing_file(file, val, false);
255 	free(file);
256 	return ret;
257 }
258 
259 static int reset_tracing_cpu(void);
260 static void reset_tracing_filters(void);
261 
reset_tracing_options(struct perf_ftrace * ftrace __maybe_unused)262 static void reset_tracing_options(struct perf_ftrace *ftrace __maybe_unused)
263 {
264 	write_tracing_option_file("function-fork", "0");
265 	write_tracing_option_file("func_stack_trace", "0");
266 	write_tracing_option_file("sleep-time", "1");
267 	write_tracing_option_file("funcgraph-irqs", "1");
268 	write_tracing_option_file("funcgraph-proc", "0");
269 	write_tracing_option_file("funcgraph-abstime", "0");
270 	write_tracing_option_file("funcgraph-tail", "0");
271 	write_tracing_option_file("latency-format", "0");
272 	write_tracing_option_file("irq-info", "0");
273 }
274 
reset_tracing_files(struct perf_ftrace * ftrace __maybe_unused)275 static int reset_tracing_files(struct perf_ftrace *ftrace __maybe_unused)
276 {
277 	if (write_tracing_file("tracing_on", "0") < 0)
278 		return -1;
279 
280 	if (write_tracing_file("current_tracer", "nop") < 0)
281 		return -1;
282 
283 	if (write_tracing_file("set_ftrace_pid", " ") < 0)
284 		return -1;
285 
286 	if (reset_tracing_cpu() < 0)
287 		return -1;
288 
289 	if (write_tracing_file("max_graph_depth", "0") < 0)
290 		return -1;
291 
292 	if (write_tracing_file("tracing_thresh", "0") < 0)
293 		return -1;
294 
295 	reset_tracing_filters();
296 	reset_tracing_options(ftrace);
297 	return 0;
298 }
299 
set_tracing_pid(struct perf_ftrace * ftrace)300 static int set_tracing_pid(struct perf_ftrace *ftrace)
301 {
302 	int i;
303 	char buf[16];
304 
305 	if (target__has_cpu(&ftrace->target))
306 		return 0;
307 
308 	for (i = 0; i < perf_thread_map__nr(ftrace->evlist->core.threads); i++) {
309 		scnprintf(buf, sizeof(buf), "%d",
310 			  perf_thread_map__pid(ftrace->evlist->core.threads, i));
311 		if (append_tracing_file("set_ftrace_pid", buf) < 0)
312 			return -1;
313 	}
314 	return 0;
315 }
316 
set_tracing_cpumask(struct perf_cpu_map * cpumap)317 static int set_tracing_cpumask(struct perf_cpu_map *cpumap)
318 {
319 	char *cpumask;
320 	size_t mask_size;
321 	int ret;
322 	int last_cpu;
323 
324 	last_cpu = perf_cpu_map__cpu(cpumap, perf_cpu_map__nr(cpumap) - 1).cpu;
325 	mask_size = last_cpu / 4 + 2; /* one more byte for EOS */
326 	mask_size += last_cpu / 32; /* ',' is needed for every 32th cpus */
327 
328 	cpumask = malloc(mask_size);
329 	if (cpumask == NULL) {
330 		pr_debug("failed to allocate cpu mask\n");
331 		return -1;
332 	}
333 
334 	cpu_map__snprint_mask(cpumap, cpumask, mask_size);
335 
336 	ret = write_tracing_file("tracing_cpumask", cpumask);
337 
338 	free(cpumask);
339 	return ret;
340 }
341 
set_tracing_cpu(struct perf_ftrace * ftrace)342 static int set_tracing_cpu(struct perf_ftrace *ftrace)
343 {
344 	struct perf_cpu_map *cpumap = ftrace->evlist->core.user_requested_cpus;
345 
346 	if (!target__has_cpu(&ftrace->target))
347 		return 0;
348 
349 	return set_tracing_cpumask(cpumap);
350 }
351 
set_tracing_func_stack_trace(struct perf_ftrace * ftrace)352 static int set_tracing_func_stack_trace(struct perf_ftrace *ftrace)
353 {
354 	if (!ftrace->func_stack_trace)
355 		return 0;
356 
357 	if (write_tracing_option_file("func_stack_trace", "1") < 0)
358 		return -1;
359 
360 	return 0;
361 }
362 
set_tracing_func_irqinfo(struct perf_ftrace * ftrace)363 static int set_tracing_func_irqinfo(struct perf_ftrace *ftrace)
364 {
365 	if (!ftrace->func_irq_info)
366 		return 0;
367 
368 	if (write_tracing_option_file("irq-info", "1") < 0)
369 		return -1;
370 
371 	return 0;
372 }
373 
reset_tracing_cpu(void)374 static int reset_tracing_cpu(void)
375 {
376 	struct perf_cpu_map *cpumap = perf_cpu_map__new_online_cpus();
377 	int ret;
378 
379 	ret = set_tracing_cpumask(cpumap);
380 	perf_cpu_map__put(cpumap);
381 	return ret;
382 }
383 
__set_tracing_filter(const char * filter_file,struct list_head * funcs)384 static int __set_tracing_filter(const char *filter_file, struct list_head *funcs)
385 {
386 	struct filter_entry *pos;
387 
388 	list_for_each_entry(pos, funcs, list) {
389 		if (append_tracing_file(filter_file, pos->name) < 0)
390 			return -1;
391 	}
392 
393 	return 0;
394 }
395 
set_tracing_filters(struct perf_ftrace * ftrace)396 static int set_tracing_filters(struct perf_ftrace *ftrace)
397 {
398 	int ret;
399 
400 	ret = __set_tracing_filter("set_ftrace_filter", &ftrace->filters);
401 	if (ret < 0)
402 		return ret;
403 
404 	ret = __set_tracing_filter("set_ftrace_notrace", &ftrace->notrace);
405 	if (ret < 0)
406 		return ret;
407 
408 	ret = __set_tracing_filter("set_graph_function", &ftrace->graph_funcs);
409 	if (ret < 0)
410 		return ret;
411 
412 	/* old kernels do not have this filter */
413 	__set_tracing_filter("set_graph_notrace", &ftrace->nograph_funcs);
414 
415 	return ret;
416 }
417 
reset_tracing_filters(void)418 static void reset_tracing_filters(void)
419 {
420 	write_tracing_file("set_ftrace_filter", " ");
421 	write_tracing_file("set_ftrace_notrace", " ");
422 	write_tracing_file("set_graph_function", " ");
423 	write_tracing_file("set_graph_notrace", " ");
424 }
425 
set_tracing_depth(struct perf_ftrace * ftrace)426 static int set_tracing_depth(struct perf_ftrace *ftrace)
427 {
428 	if (ftrace->graph_depth == 0)
429 		return 0;
430 
431 	if (ftrace->graph_depth < 0) {
432 		pr_err("invalid graph depth: %d\n", ftrace->graph_depth);
433 		return -1;
434 	}
435 
436 	if (write_tracing_file_int("max_graph_depth", ftrace->graph_depth) < 0)
437 		return -1;
438 
439 	return 0;
440 }
441 
set_tracing_percpu_buffer_size(struct perf_ftrace * ftrace)442 static int set_tracing_percpu_buffer_size(struct perf_ftrace *ftrace)
443 {
444 	int ret;
445 
446 	if (ftrace->percpu_buffer_size == 0)
447 		return 0;
448 
449 	ret = write_tracing_file_int("buffer_size_kb",
450 				     ftrace->percpu_buffer_size / 1024);
451 	if (ret < 0)
452 		return ret;
453 
454 	return 0;
455 }
456 
set_tracing_trace_inherit(struct perf_ftrace * ftrace)457 static int set_tracing_trace_inherit(struct perf_ftrace *ftrace)
458 {
459 	if (!ftrace->inherit)
460 		return 0;
461 
462 	if (write_tracing_option_file("function-fork", "1") < 0)
463 		return -1;
464 
465 	return 0;
466 }
467 
set_tracing_sleep_time(struct perf_ftrace * ftrace)468 static int set_tracing_sleep_time(struct perf_ftrace *ftrace)
469 {
470 	if (!ftrace->graph_nosleep_time)
471 		return 0;
472 
473 	if (write_tracing_option_file("sleep-time", "0") < 0)
474 		return -1;
475 
476 	return 0;
477 }
478 
set_tracing_funcgraph_irqs(struct perf_ftrace * ftrace)479 static int set_tracing_funcgraph_irqs(struct perf_ftrace *ftrace)
480 {
481 	if (!ftrace->graph_noirqs)
482 		return 0;
483 
484 	if (write_tracing_option_file("funcgraph-irqs", "0") < 0)
485 		return -1;
486 
487 	return 0;
488 }
489 
set_tracing_funcgraph_verbose(struct perf_ftrace * ftrace)490 static int set_tracing_funcgraph_verbose(struct perf_ftrace *ftrace)
491 {
492 	if (!ftrace->graph_verbose)
493 		return 0;
494 
495 	if (write_tracing_option_file("funcgraph-proc", "1") < 0)
496 		return -1;
497 
498 	if (write_tracing_option_file("funcgraph-abstime", "1") < 0)
499 		return -1;
500 
501 	if (write_tracing_option_file("latency-format", "1") < 0)
502 		return -1;
503 
504 	return 0;
505 }
506 
set_tracing_funcgraph_tail(struct perf_ftrace * ftrace)507 static int set_tracing_funcgraph_tail(struct perf_ftrace *ftrace)
508 {
509 	if (!ftrace->graph_tail)
510 		return 0;
511 
512 	if (write_tracing_option_file("funcgraph-tail", "1") < 0)
513 		return -1;
514 
515 	return 0;
516 }
517 
set_tracing_thresh(struct perf_ftrace * ftrace)518 static int set_tracing_thresh(struct perf_ftrace *ftrace)
519 {
520 	int ret;
521 
522 	if (ftrace->graph_thresh == 0)
523 		return 0;
524 
525 	ret = write_tracing_file_int("tracing_thresh", ftrace->graph_thresh);
526 	if (ret < 0)
527 		return ret;
528 
529 	return 0;
530 }
531 
set_tracing_options(struct perf_ftrace * ftrace)532 static int set_tracing_options(struct perf_ftrace *ftrace)
533 {
534 	if (set_tracing_pid(ftrace) < 0) {
535 		pr_err("failed to set ftrace pid\n");
536 		return -1;
537 	}
538 
539 	if (set_tracing_cpu(ftrace) < 0) {
540 		pr_err("failed to set tracing cpumask\n");
541 		return -1;
542 	}
543 
544 	if (set_tracing_func_stack_trace(ftrace) < 0) {
545 		pr_err("failed to set tracing option func_stack_trace\n");
546 		return -1;
547 	}
548 
549 	if (set_tracing_func_irqinfo(ftrace) < 0) {
550 		pr_err("failed to set tracing option irq-info\n");
551 		return -1;
552 	}
553 
554 	if (set_tracing_filters(ftrace) < 0) {
555 		pr_err("failed to set tracing filters\n");
556 		return -1;
557 	}
558 
559 	if (set_tracing_depth(ftrace) < 0) {
560 		pr_err("failed to set graph depth\n");
561 		return -1;
562 	}
563 
564 	if (set_tracing_percpu_buffer_size(ftrace) < 0) {
565 		pr_err("failed to set tracing per-cpu buffer size\n");
566 		return -1;
567 	}
568 
569 	if (set_tracing_trace_inherit(ftrace) < 0) {
570 		pr_err("failed to set tracing option function-fork\n");
571 		return -1;
572 	}
573 
574 	if (set_tracing_sleep_time(ftrace) < 0) {
575 		pr_err("failed to set tracing option sleep-time\n");
576 		return -1;
577 	}
578 
579 	if (set_tracing_funcgraph_irqs(ftrace) < 0) {
580 		pr_err("failed to set tracing option funcgraph-irqs\n");
581 		return -1;
582 	}
583 
584 	if (set_tracing_funcgraph_verbose(ftrace) < 0) {
585 		pr_err("failed to set tracing option funcgraph-proc/funcgraph-abstime\n");
586 		return -1;
587 	}
588 
589 	if (set_tracing_thresh(ftrace) < 0) {
590 		pr_err("failed to set tracing thresh\n");
591 		return -1;
592 	}
593 
594 	if (set_tracing_funcgraph_tail(ftrace) < 0) {
595 		pr_err("failed to set tracing option funcgraph-tail\n");
596 		return -1;
597 	}
598 
599 	return 0;
600 }
601 
select_tracer(struct perf_ftrace * ftrace)602 static void select_tracer(struct perf_ftrace *ftrace)
603 {
604 	bool graph = !list_empty(&ftrace->graph_funcs) ||
605 		     !list_empty(&ftrace->nograph_funcs);
606 	bool func = !list_empty(&ftrace->filters) ||
607 		    !list_empty(&ftrace->notrace);
608 
609 	/* The function_graph has priority over function tracer. */
610 	if (graph)
611 		ftrace->tracer = "function_graph";
612 	else if (func)
613 		ftrace->tracer = "function";
614 	/* Otherwise, the default tracer is used. */
615 
616 	pr_debug("%s tracer is used\n", ftrace->tracer);
617 }
618 
__cmd_ftrace(struct perf_ftrace * ftrace)619 static int __cmd_ftrace(struct perf_ftrace *ftrace)
620 {
621 	char *trace_file;
622 	int trace_fd;
623 	char buf[4096];
624 	struct pollfd pollfd = {
625 		.events = POLLIN,
626 	};
627 
628 	select_tracer(ftrace);
629 
630 	if (reset_tracing_files(ftrace) < 0) {
631 		pr_err("failed to reset ftrace\n");
632 		goto out;
633 	}
634 
635 	/* reset ftrace buffer */
636 	if (write_tracing_file("trace", "0") < 0)
637 		goto out;
638 
639 	if (set_tracing_options(ftrace) < 0)
640 		goto out_reset;
641 
642 	if (write_tracing_file("current_tracer", ftrace->tracer) < 0) {
643 		pr_err("failed to set current_tracer to %s\n", ftrace->tracer);
644 		goto out_reset;
645 	}
646 
647 	setup_pager();
648 
649 	trace_file = get_tracing_file("trace_pipe");
650 	if (!trace_file) {
651 		pr_err("failed to open trace_pipe\n");
652 		goto out_reset;
653 	}
654 
655 	trace_fd = open(trace_file, O_RDONLY);
656 
657 	put_tracing_file(trace_file);
658 
659 	if (trace_fd < 0) {
660 		pr_err("failed to open trace_pipe\n");
661 		goto out_reset;
662 	}
663 
664 	fcntl(trace_fd, F_SETFL, O_NONBLOCK);
665 	pollfd.fd = trace_fd;
666 
667 	/* display column headers */
668 	read_tracing_file_to_stdout("trace");
669 
670 	if (!ftrace->target.initial_delay) {
671 		if (write_tracing_file("tracing_on", "1") < 0) {
672 			pr_err("can't enable tracing\n");
673 			goto out_close_fd;
674 		}
675 	}
676 
677 	evlist__start_workload(ftrace->evlist);
678 
679 	if (ftrace->target.initial_delay > 0) {
680 		usleep(ftrace->target.initial_delay * 1000);
681 		if (write_tracing_file("tracing_on", "1") < 0) {
682 			pr_err("can't enable tracing\n");
683 			goto out_close_fd;
684 		}
685 	}
686 
687 	while (!done) {
688 		if (poll(&pollfd, 1, -1) < 0)
689 			break;
690 
691 		if (pollfd.revents & POLLIN) {
692 			int n = read(trace_fd, buf, sizeof(buf));
693 			if (n < 0)
694 				break;
695 			if (fwrite(buf, n, 1, stdout) != 1)
696 				break;
697 			/* flush output since stdout is in full buffering mode due to pager */
698 			fflush(stdout);
699 		}
700 	}
701 
702 	write_tracing_file("tracing_on", "0");
703 
704 	if (workload_exec_errno) {
705 		const char *emsg = str_error_r(workload_exec_errno, buf, sizeof(buf));
706 		/* flush stdout first so below error msg appears at the end. */
707 		fflush(stdout);
708 		pr_err("workload failed: %s\n", emsg);
709 		goto out_close_fd;
710 	}
711 
712 	/* read remaining buffer contents */
713 	while (true) {
714 		int n = read(trace_fd, buf, sizeof(buf));
715 		if (n <= 0)
716 			break;
717 		if (fwrite(buf, n, 1, stdout) != 1)
718 			break;
719 	}
720 
721 out_close_fd:
722 	close(trace_fd);
723 out_reset:
724 	reset_tracing_files(ftrace);
725 out:
726 	return (done && !workload_exec_errno) ? 0 : -1;
727 }
728 
make_histogram(int buckets[],char * buf,size_t len,char * linebuf,bool use_nsec)729 static void make_histogram(int buckets[], char *buf, size_t len, char *linebuf,
730 			   bool use_nsec)
731 {
732 	char *p, *q;
733 	char *unit;
734 	double num;
735 	int i;
736 
737 	/* ensure NUL termination */
738 	buf[len] = '\0';
739 
740 	/* handle data line by line */
741 	for (p = buf; (q = strchr(p, '\n')) != NULL; p = q + 1) {
742 		*q = '\0';
743 		/* move it to the line buffer */
744 		strcat(linebuf, p);
745 
746 		/*
747 		 * parse trace output to get function duration like in
748 		 *
749 		 * # tracer: function_graph
750 		 * #
751 		 * # CPU  DURATION                  FUNCTION CALLS
752 		 * # |     |   |                     |   |   |   |
753 		 *  1) + 10.291 us   |  do_filp_open();
754 		 *  1)   4.889 us    |  do_filp_open();
755 		 *  1)   6.086 us    |  do_filp_open();
756 		 *
757 		 */
758 		if (linebuf[0] == '#')
759 			goto next;
760 
761 		/* ignore CPU */
762 		p = strchr(linebuf, ')');
763 		if (p == NULL)
764 			p = linebuf;
765 
766 		while (*p && !isdigit(*p) && (*p != '|'))
767 			p++;
768 
769 		/* no duration */
770 		if (*p == '\0' || *p == '|')
771 			goto next;
772 
773 		num = strtod(p, &unit);
774 		if (!unit || strncmp(unit, " us", 3))
775 			goto next;
776 
777 		if (use_nsec)
778 			num *= 1000;
779 
780 		i = log2(num);
781 		if (i < 0)
782 			i = 0;
783 		if (i >= NUM_BUCKET)
784 			i = NUM_BUCKET - 1;
785 
786 		buckets[i]++;
787 
788 next:
789 		/* empty the line buffer for the next output  */
790 		linebuf[0] = '\0';
791 	}
792 
793 	/* preserve any remaining output (before newline) */
794 	strcat(linebuf, p);
795 }
796 
display_histogram(int buckets[],bool use_nsec)797 static void display_histogram(int buckets[], bool use_nsec)
798 {
799 	int i;
800 	int total = 0;
801 	int bar_total = 46;  /* to fit in 80 column */
802 	char bar[] = "###############################################";
803 	int bar_len;
804 
805 	for (i = 0; i < NUM_BUCKET; i++)
806 		total += buckets[i];
807 
808 	if (total == 0) {
809 		printf("No data found\n");
810 		return;
811 	}
812 
813 	printf("# %14s | %10s | %-*s |\n",
814 	       "  DURATION    ", "COUNT", bar_total, "GRAPH");
815 
816 	bar_len = buckets[0] * bar_total / total;
817 	printf("  %4d - %-4d %s | %10d | %.*s%*s |\n",
818 	       0, 1, "us", buckets[0], bar_len, bar, bar_total - bar_len, "");
819 
820 	for (i = 1; i < NUM_BUCKET - 1; i++) {
821 		int start = (1 << (i - 1));
822 		int stop = 1 << i;
823 		const char *unit = use_nsec ? "ns" : "us";
824 
825 		if (start >= 1024) {
826 			start >>= 10;
827 			stop >>= 10;
828 			unit = use_nsec ? "us" : "ms";
829 		}
830 		bar_len = buckets[i] * bar_total / total;
831 		printf("  %4d - %-4d %s | %10d | %.*s%*s |\n",
832 		       start, stop, unit, buckets[i], bar_len, bar,
833 		       bar_total - bar_len, "");
834 	}
835 
836 	bar_len = buckets[NUM_BUCKET - 1] * bar_total / total;
837 	printf("  %4d - %-4s %s | %10d | %.*s%*s |\n",
838 	       1, "...", use_nsec ? "ms" : " s", buckets[NUM_BUCKET - 1],
839 	       bar_len, bar, bar_total - bar_len, "");
840 
841 }
842 
prepare_func_latency(struct perf_ftrace * ftrace)843 static int prepare_func_latency(struct perf_ftrace *ftrace)
844 {
845 	char *trace_file;
846 	int fd;
847 
848 	if (ftrace->target.use_bpf)
849 		return perf_ftrace__latency_prepare_bpf(ftrace);
850 
851 	if (reset_tracing_files(ftrace) < 0) {
852 		pr_err("failed to reset ftrace\n");
853 		return -1;
854 	}
855 
856 	/* reset ftrace buffer */
857 	if (write_tracing_file("trace", "0") < 0)
858 		return -1;
859 
860 	if (set_tracing_options(ftrace) < 0)
861 		return -1;
862 
863 	/* force to use the function_graph tracer to track duration */
864 	if (write_tracing_file("current_tracer", "function_graph") < 0) {
865 		pr_err("failed to set current_tracer to function_graph\n");
866 		return -1;
867 	}
868 
869 	trace_file = get_tracing_file("trace_pipe");
870 	if (!trace_file) {
871 		pr_err("failed to open trace_pipe\n");
872 		return -1;
873 	}
874 
875 	fd = open(trace_file, O_RDONLY);
876 	if (fd < 0)
877 		pr_err("failed to open trace_pipe\n");
878 
879 	put_tracing_file(trace_file);
880 	return fd;
881 }
882 
start_func_latency(struct perf_ftrace * ftrace)883 static int start_func_latency(struct perf_ftrace *ftrace)
884 {
885 	if (ftrace->target.use_bpf)
886 		return perf_ftrace__latency_start_bpf(ftrace);
887 
888 	if (write_tracing_file("tracing_on", "1") < 0) {
889 		pr_err("can't enable tracing\n");
890 		return -1;
891 	}
892 
893 	return 0;
894 }
895 
stop_func_latency(struct perf_ftrace * ftrace)896 static int stop_func_latency(struct perf_ftrace *ftrace)
897 {
898 	if (ftrace->target.use_bpf)
899 		return perf_ftrace__latency_stop_bpf(ftrace);
900 
901 	write_tracing_file("tracing_on", "0");
902 	return 0;
903 }
904 
read_func_latency(struct perf_ftrace * ftrace,int buckets[])905 static int read_func_latency(struct perf_ftrace *ftrace, int buckets[])
906 {
907 	if (ftrace->target.use_bpf)
908 		return perf_ftrace__latency_read_bpf(ftrace, buckets);
909 
910 	return 0;
911 }
912 
cleanup_func_latency(struct perf_ftrace * ftrace)913 static int cleanup_func_latency(struct perf_ftrace *ftrace)
914 {
915 	if (ftrace->target.use_bpf)
916 		return perf_ftrace__latency_cleanup_bpf(ftrace);
917 
918 	reset_tracing_files(ftrace);
919 	return 0;
920 }
921 
__cmd_latency(struct perf_ftrace * ftrace)922 static int __cmd_latency(struct perf_ftrace *ftrace)
923 {
924 	int trace_fd;
925 	char buf[4096];
926 	char line[256];
927 	struct pollfd pollfd = {
928 		.events = POLLIN,
929 	};
930 	int buckets[NUM_BUCKET] = { };
931 
932 	trace_fd = prepare_func_latency(ftrace);
933 	if (trace_fd < 0)
934 		goto out;
935 
936 	fcntl(trace_fd, F_SETFL, O_NONBLOCK);
937 	pollfd.fd = trace_fd;
938 
939 	if (start_func_latency(ftrace) < 0)
940 		goto out;
941 
942 	evlist__start_workload(ftrace->evlist);
943 
944 	line[0] = '\0';
945 	while (!done) {
946 		if (poll(&pollfd, 1, -1) < 0)
947 			break;
948 
949 		if (pollfd.revents & POLLIN) {
950 			int n = read(trace_fd, buf, sizeof(buf) - 1);
951 			if (n < 0)
952 				break;
953 
954 			make_histogram(buckets, buf, n, line, ftrace->use_nsec);
955 		}
956 	}
957 
958 	stop_func_latency(ftrace);
959 
960 	if (workload_exec_errno) {
961 		const char *emsg = str_error_r(workload_exec_errno, buf, sizeof(buf));
962 		pr_err("workload failed: %s\n", emsg);
963 		goto out;
964 	}
965 
966 	/* read remaining buffer contents */
967 	while (!ftrace->target.use_bpf) {
968 		int n = read(trace_fd, buf, sizeof(buf) - 1);
969 		if (n <= 0)
970 			break;
971 		make_histogram(buckets, buf, n, line, ftrace->use_nsec);
972 	}
973 
974 	read_func_latency(ftrace, buckets);
975 
976 	display_histogram(buckets, ftrace->use_nsec);
977 
978 out:
979 	close(trace_fd);
980 	cleanup_func_latency(ftrace);
981 
982 	return (done && !workload_exec_errno) ? 0 : -1;
983 }
984 
profile_hash(long func,void * ctx __maybe_unused)985 static size_t profile_hash(long func, void *ctx __maybe_unused)
986 {
987 	return str_hash((char *)func);
988 }
989 
profile_equal(long func1,long func2,void * ctx __maybe_unused)990 static bool profile_equal(long func1, long func2, void *ctx __maybe_unused)
991 {
992 	return !strcmp((char *)func1, (char *)func2);
993 }
994 
prepare_func_profile(struct perf_ftrace * ftrace)995 static int prepare_func_profile(struct perf_ftrace *ftrace)
996 {
997 	ftrace->tracer = "function_graph";
998 	ftrace->graph_tail = 1;
999 
1000 	ftrace->profile_hash = hashmap__new(profile_hash, profile_equal, NULL);
1001 	if (ftrace->profile_hash == NULL)
1002 		return -ENOMEM;
1003 
1004 	return 0;
1005 }
1006 
1007 /* This is saved in a hashmap keyed by the function name */
1008 struct ftrace_profile_data {
1009 	struct stats st;
1010 };
1011 
add_func_duration(struct perf_ftrace * ftrace,char * func,double time_ns)1012 static int add_func_duration(struct perf_ftrace *ftrace, char *func, double time_ns)
1013 {
1014 	struct ftrace_profile_data *prof = NULL;
1015 
1016 	if (!hashmap__find(ftrace->profile_hash, func, &prof)) {
1017 		char *key = strdup(func);
1018 
1019 		if (key == NULL)
1020 			return -ENOMEM;
1021 
1022 		prof = zalloc(sizeof(*prof));
1023 		if (prof == NULL) {
1024 			free(key);
1025 			return -ENOMEM;
1026 		}
1027 
1028 		init_stats(&prof->st);
1029 		hashmap__add(ftrace->profile_hash, key, prof);
1030 	}
1031 
1032 	update_stats(&prof->st, time_ns);
1033 	return 0;
1034 }
1035 
1036 /*
1037  * The ftrace function_graph text output normally looks like below:
1038  *
1039  * CPU   DURATION       FUNCTION
1040  *
1041  *  0)               |  syscall_trace_enter.isra.0() {
1042  *  0)               |    __audit_syscall_entry() {
1043  *  0)               |      auditd_test_task() {
1044  *  0)   0.271 us    |        __rcu_read_lock();
1045  *  0)   0.275 us    |        __rcu_read_unlock();
1046  *  0)   1.254 us    |      } /\* auditd_test_task *\/
1047  *  0)   0.279 us    |      ktime_get_coarse_real_ts64();
1048  *  0)   2.227 us    |    } /\* __audit_syscall_entry *\/
1049  *  0)   2.713 us    |  } /\* syscall_trace_enter.isra.0 *\/
1050  *
1051  *  Parse the line and get the duration and function name.
1052  */
parse_func_duration(struct perf_ftrace * ftrace,char * line,size_t len)1053 static int parse_func_duration(struct perf_ftrace *ftrace, char *line, size_t len)
1054 {
1055 	char *p;
1056 	char *func;
1057 	double duration;
1058 
1059 	/* skip CPU */
1060 	p = strchr(line, ')');
1061 	if (p == NULL)
1062 		return 0;
1063 
1064 	/* get duration */
1065 	p = skip_spaces(p + 1);
1066 
1067 	/* no duration? */
1068 	if (p == NULL || *p == '|')
1069 		return 0;
1070 
1071 	/* skip markers like '*' or '!' for longer than ms */
1072 	if (!isdigit(*p))
1073 		p++;
1074 
1075 	duration = strtod(p, &p);
1076 
1077 	if (strncmp(p, " us", 3)) {
1078 		pr_debug("non-usec time found.. ignoring\n");
1079 		return 0;
1080 	}
1081 
1082 	/*
1083 	 * profile stat keeps the max and min values as integer,
1084 	 * convert to nsec time so that we can have accurate max.
1085 	 */
1086 	duration *= 1000;
1087 
1088 	/* skip to the pipe */
1089 	while (p < line + len && *p != '|')
1090 		p++;
1091 
1092 	if (*p++ != '|')
1093 		return -EINVAL;
1094 
1095 	/* get function name */
1096 	func = skip_spaces(p);
1097 
1098 	/* skip the closing bracket and the start of comment */
1099 	if (*func == '}')
1100 		func += 5;
1101 
1102 	/* remove semi-colon or end of comment at the end */
1103 	p = line + len - 1;
1104 	while (!isalnum(*p) && *p != ']') {
1105 		*p = '\0';
1106 		--p;
1107 	}
1108 
1109 	return add_func_duration(ftrace, func, duration);
1110 }
1111 
1112 enum perf_ftrace_profile_sort_key {
1113 	PFP_SORT_TOTAL = 0,
1114 	PFP_SORT_AVG,
1115 	PFP_SORT_MAX,
1116 	PFP_SORT_COUNT,
1117 	PFP_SORT_NAME,
1118 };
1119 
1120 static enum perf_ftrace_profile_sort_key profile_sort = PFP_SORT_TOTAL;
1121 
cmp_profile_data(const void * a,const void * b)1122 static int cmp_profile_data(const void *a, const void *b)
1123 {
1124 	const struct hashmap_entry *e1 = *(const struct hashmap_entry **)a;
1125 	const struct hashmap_entry *e2 = *(const struct hashmap_entry **)b;
1126 	struct ftrace_profile_data *p1 = e1->pvalue;
1127 	struct ftrace_profile_data *p2 = e2->pvalue;
1128 	double v1, v2;
1129 
1130 	switch (profile_sort) {
1131 	case PFP_SORT_NAME:
1132 		return strcmp(e1->pkey, e2->pkey);
1133 	case PFP_SORT_AVG:
1134 		v1 = p1->st.mean;
1135 		v2 = p2->st.mean;
1136 		break;
1137 	case PFP_SORT_MAX:
1138 		v1 = p1->st.max;
1139 		v2 = p2->st.max;
1140 		break;
1141 	case PFP_SORT_COUNT:
1142 		v1 = p1->st.n;
1143 		v2 = p2->st.n;
1144 		break;
1145 	case PFP_SORT_TOTAL:
1146 	default:
1147 		v1 = p1->st.n * p1->st.mean;
1148 		v2 = p2->st.n * p2->st.mean;
1149 		break;
1150 	}
1151 
1152 	if (v1 > v2)
1153 		return -1;
1154 	else
1155 		return 1;
1156 }
1157 
print_profile_result(struct perf_ftrace * ftrace)1158 static void print_profile_result(struct perf_ftrace *ftrace)
1159 {
1160 	struct hashmap_entry *entry, **profile;
1161 	size_t i, nr, bkt;
1162 
1163 	nr = hashmap__size(ftrace->profile_hash);
1164 	if (nr == 0)
1165 		return;
1166 
1167 	profile = calloc(nr, sizeof(*profile));
1168 	if (profile == NULL) {
1169 		pr_err("failed to allocate memory for the result\n");
1170 		return;
1171 	}
1172 
1173 	i = 0;
1174 	hashmap__for_each_entry(ftrace->profile_hash, entry, bkt)
1175 		profile[i++] = entry;
1176 
1177 	assert(i == nr);
1178 
1179 	//cmp_profile_data(profile[0], profile[1]);
1180 	qsort(profile, nr, sizeof(*profile), cmp_profile_data);
1181 
1182 	printf("# %10s %10s %10s %10s   %s\n",
1183 	       "Total (us)", "Avg (us)", "Max (us)", "Count", "Function");
1184 
1185 	for (i = 0; i < nr; i++) {
1186 		const char *name = profile[i]->pkey;
1187 		struct ftrace_profile_data *p = profile[i]->pvalue;
1188 
1189 		printf("%12.3f %10.3f %6"PRIu64".%03"PRIu64" %10.0f   %s\n",
1190 		       p->st.n * p->st.mean / 1000, p->st.mean / 1000,
1191 		       p->st.max / 1000, p->st.max % 1000, p->st.n, name);
1192 	}
1193 
1194 	free(profile);
1195 
1196 	hashmap__for_each_entry(ftrace->profile_hash, entry, bkt) {
1197 		free((char *)entry->pkey);
1198 		free(entry->pvalue);
1199 	}
1200 
1201 	hashmap__free(ftrace->profile_hash);
1202 	ftrace->profile_hash = NULL;
1203 }
1204 
__cmd_profile(struct perf_ftrace * ftrace)1205 static int __cmd_profile(struct perf_ftrace *ftrace)
1206 {
1207 	char *trace_file;
1208 	int trace_fd;
1209 	char buf[4096];
1210 	struct io io;
1211 	char *line = NULL;
1212 	size_t line_len = 0;
1213 
1214 	if (prepare_func_profile(ftrace) < 0) {
1215 		pr_err("failed to prepare func profiler\n");
1216 		goto out;
1217 	}
1218 
1219 	if (reset_tracing_files(ftrace) < 0) {
1220 		pr_err("failed to reset ftrace\n");
1221 		goto out;
1222 	}
1223 
1224 	/* reset ftrace buffer */
1225 	if (write_tracing_file("trace", "0") < 0)
1226 		goto out;
1227 
1228 	if (set_tracing_options(ftrace) < 0)
1229 		return -1;
1230 
1231 	if (write_tracing_file("current_tracer", ftrace->tracer) < 0) {
1232 		pr_err("failed to set current_tracer to %s\n", ftrace->tracer);
1233 		goto out_reset;
1234 	}
1235 
1236 	setup_pager();
1237 
1238 	trace_file = get_tracing_file("trace_pipe");
1239 	if (!trace_file) {
1240 		pr_err("failed to open trace_pipe\n");
1241 		goto out_reset;
1242 	}
1243 
1244 	trace_fd = open(trace_file, O_RDONLY);
1245 
1246 	put_tracing_file(trace_file);
1247 
1248 	if (trace_fd < 0) {
1249 		pr_err("failed to open trace_pipe\n");
1250 		goto out_reset;
1251 	}
1252 
1253 	fcntl(trace_fd, F_SETFL, O_NONBLOCK);
1254 
1255 	if (write_tracing_file("tracing_on", "1") < 0) {
1256 		pr_err("can't enable tracing\n");
1257 		goto out_close_fd;
1258 	}
1259 
1260 	evlist__start_workload(ftrace->evlist);
1261 
1262 	io__init(&io, trace_fd, buf, sizeof(buf));
1263 	io.timeout_ms = -1;
1264 
1265 	while (!done && !io.eof) {
1266 		if (io__getline(&io, &line, &line_len) < 0)
1267 			break;
1268 
1269 		if (parse_func_duration(ftrace, line, line_len) < 0)
1270 			break;
1271 	}
1272 
1273 	write_tracing_file("tracing_on", "0");
1274 
1275 	if (workload_exec_errno) {
1276 		const char *emsg = str_error_r(workload_exec_errno, buf, sizeof(buf));
1277 		/* flush stdout first so below error msg appears at the end. */
1278 		fflush(stdout);
1279 		pr_err("workload failed: %s\n", emsg);
1280 		goto out_free_line;
1281 	}
1282 
1283 	/* read remaining buffer contents */
1284 	io.timeout_ms = 0;
1285 	while (!io.eof) {
1286 		if (io__getline(&io, &line, &line_len) < 0)
1287 			break;
1288 
1289 		if (parse_func_duration(ftrace, line, line_len) < 0)
1290 			break;
1291 	}
1292 
1293 	print_profile_result(ftrace);
1294 
1295 out_free_line:
1296 	free(line);
1297 out_close_fd:
1298 	close(trace_fd);
1299 out_reset:
1300 	reset_tracing_files(ftrace);
1301 out:
1302 	return (done && !workload_exec_errno) ? 0 : -1;
1303 }
1304 
perf_ftrace_config(const char * var,const char * value,void * cb)1305 static int perf_ftrace_config(const char *var, const char *value, void *cb)
1306 {
1307 	struct perf_ftrace *ftrace = cb;
1308 
1309 	if (!strstarts(var, "ftrace."))
1310 		return 0;
1311 
1312 	if (strcmp(var, "ftrace.tracer"))
1313 		return -1;
1314 
1315 	if (!strcmp(value, "function_graph") ||
1316 	    !strcmp(value, "function")) {
1317 		ftrace->tracer = value;
1318 		return 0;
1319 	}
1320 
1321 	pr_err("Please select \"function_graph\" (default) or \"function\"\n");
1322 	return -1;
1323 }
1324 
list_function_cb(char * str,void * arg)1325 static void list_function_cb(char *str, void *arg)
1326 {
1327 	struct strfilter *filter = (struct strfilter *)arg;
1328 
1329 	if (strfilter__compare(filter, str))
1330 		printf("%s", str);
1331 }
1332 
opt_list_avail_functions(const struct option * opt __maybe_unused,const char * str,int unset)1333 static int opt_list_avail_functions(const struct option *opt __maybe_unused,
1334 				    const char *str, int unset)
1335 {
1336 	struct strfilter *filter;
1337 	const char *err = NULL;
1338 	int ret;
1339 
1340 	if (unset || !str)
1341 		return -1;
1342 
1343 	filter = strfilter__new(str, &err);
1344 	if (!filter)
1345 		return err ? -EINVAL : -ENOMEM;
1346 
1347 	ret = strfilter__or(filter, str, &err);
1348 	if (ret == -EINVAL) {
1349 		pr_err("Filter parse error at %td.\n", err - str + 1);
1350 		pr_err("Source: \"%s\"\n", str);
1351 		pr_err("         %*c\n", (int)(err - str + 1), '^');
1352 		strfilter__delete(filter);
1353 		return ret;
1354 	}
1355 
1356 	ret = read_tracing_file_by_line("available_filter_functions",
1357 					list_function_cb, filter);
1358 	strfilter__delete(filter);
1359 	if (ret < 0)
1360 		return ret;
1361 
1362 	exit(0);
1363 }
1364 
parse_filter_func(const struct option * opt,const char * str,int unset __maybe_unused)1365 static int parse_filter_func(const struct option *opt, const char *str,
1366 			     int unset __maybe_unused)
1367 {
1368 	struct list_head *head = opt->value;
1369 	struct filter_entry *entry;
1370 
1371 	entry = malloc(sizeof(*entry) + strlen(str) + 1);
1372 	if (entry == NULL)
1373 		return -ENOMEM;
1374 
1375 	strcpy(entry->name, str);
1376 	list_add_tail(&entry->list, head);
1377 
1378 	return 0;
1379 }
1380 
delete_filter_func(struct list_head * head)1381 static void delete_filter_func(struct list_head *head)
1382 {
1383 	struct filter_entry *pos, *tmp;
1384 
1385 	list_for_each_entry_safe(pos, tmp, head, list) {
1386 		list_del_init(&pos->list);
1387 		free(pos);
1388 	}
1389 }
1390 
parse_buffer_size(const struct option * opt,const char * str,int unset)1391 static int parse_buffer_size(const struct option *opt,
1392 			     const char *str, int unset)
1393 {
1394 	unsigned long *s = (unsigned long *)opt->value;
1395 	static struct parse_tag tags_size[] = {
1396 		{ .tag  = 'B', .mult = 1       },
1397 		{ .tag  = 'K', .mult = 1 << 10 },
1398 		{ .tag  = 'M', .mult = 1 << 20 },
1399 		{ .tag  = 'G', .mult = 1 << 30 },
1400 		{ .tag  = 0 },
1401 	};
1402 	unsigned long val;
1403 
1404 	if (unset) {
1405 		*s = 0;
1406 		return 0;
1407 	}
1408 
1409 	val = parse_tag_value(str, tags_size);
1410 	if (val != (unsigned long) -1) {
1411 		if (val < 1024) {
1412 			pr_err("buffer size too small, must larger than 1KB.");
1413 			return -1;
1414 		}
1415 		*s = val;
1416 		return 0;
1417 	}
1418 
1419 	return -1;
1420 }
1421 
parse_func_tracer_opts(const struct option * opt,const char * str,int unset)1422 static int parse_func_tracer_opts(const struct option *opt,
1423 				  const char *str, int unset)
1424 {
1425 	int ret;
1426 	struct perf_ftrace *ftrace = (struct perf_ftrace *) opt->value;
1427 	struct sublevel_option func_tracer_opts[] = {
1428 		{ .name = "call-graph",	.value_ptr = &ftrace->func_stack_trace },
1429 		{ .name = "irq-info",	.value_ptr = &ftrace->func_irq_info },
1430 		{ .name = NULL, }
1431 	};
1432 
1433 	if (unset)
1434 		return 0;
1435 
1436 	ret = perf_parse_sublevel_options(str, func_tracer_opts);
1437 	if (ret)
1438 		return ret;
1439 
1440 	return 0;
1441 }
1442 
parse_graph_tracer_opts(const struct option * opt,const char * str,int unset)1443 static int parse_graph_tracer_opts(const struct option *opt,
1444 				  const char *str, int unset)
1445 {
1446 	int ret;
1447 	struct perf_ftrace *ftrace = (struct perf_ftrace *) opt->value;
1448 	struct sublevel_option graph_tracer_opts[] = {
1449 		{ .name = "nosleep-time",	.value_ptr = &ftrace->graph_nosleep_time },
1450 		{ .name = "noirqs",		.value_ptr = &ftrace->graph_noirqs },
1451 		{ .name = "verbose",		.value_ptr = &ftrace->graph_verbose },
1452 		{ .name = "thresh",		.value_ptr = &ftrace->graph_thresh },
1453 		{ .name = "depth",		.value_ptr = &ftrace->graph_depth },
1454 		{ .name = "tail",		.value_ptr = &ftrace->graph_tail },
1455 		{ .name = NULL, }
1456 	};
1457 
1458 	if (unset)
1459 		return 0;
1460 
1461 	ret = perf_parse_sublevel_options(str, graph_tracer_opts);
1462 	if (ret)
1463 		return ret;
1464 
1465 	return 0;
1466 }
1467 
parse_sort_key(const struct option * opt,const char * str,int unset)1468 static int parse_sort_key(const struct option *opt, const char *str, int unset)
1469 {
1470 	enum perf_ftrace_profile_sort_key *key = (void *)opt->value;
1471 
1472 	if (unset)
1473 		return 0;
1474 
1475 	if (!strcmp(str, "total"))
1476 		*key = PFP_SORT_TOTAL;
1477 	else if (!strcmp(str, "avg"))
1478 		*key = PFP_SORT_AVG;
1479 	else if (!strcmp(str, "max"))
1480 		*key = PFP_SORT_MAX;
1481 	else if (!strcmp(str, "count"))
1482 		*key = PFP_SORT_COUNT;
1483 	else if (!strcmp(str, "name"))
1484 		*key = PFP_SORT_NAME;
1485 	else {
1486 		pr_err("Unknown sort key: %s\n", str);
1487 		return -1;
1488 	}
1489 	return 0;
1490 }
1491 
1492 enum perf_ftrace_subcommand {
1493 	PERF_FTRACE_NONE,
1494 	PERF_FTRACE_TRACE,
1495 	PERF_FTRACE_LATENCY,
1496 	PERF_FTRACE_PROFILE,
1497 };
1498 
cmd_ftrace(int argc,const char ** argv)1499 int cmd_ftrace(int argc, const char **argv)
1500 {
1501 	int ret;
1502 	int (*cmd_func)(struct perf_ftrace *) = NULL;
1503 	struct perf_ftrace ftrace = {
1504 		.tracer = DEFAULT_TRACER,
1505 		.target = { .uid = UINT_MAX, },
1506 	};
1507 	const struct option common_options[] = {
1508 	OPT_STRING('p', "pid", &ftrace.target.pid, "pid",
1509 		   "Trace on existing process id"),
1510 	/* TODO: Add short option -t after -t/--tracer can be removed. */
1511 	OPT_STRING(0, "tid", &ftrace.target.tid, "tid",
1512 		   "Trace on existing thread id (exclusive to --pid)"),
1513 	OPT_INCR('v', "verbose", &verbose,
1514 		 "Be more verbose"),
1515 	OPT_BOOLEAN('a', "all-cpus", &ftrace.target.system_wide,
1516 		    "System-wide collection from all CPUs"),
1517 	OPT_STRING('C', "cpu", &ftrace.target.cpu_list, "cpu",
1518 		    "List of cpus to monitor"),
1519 	OPT_END()
1520 	};
1521 	const struct option ftrace_options[] = {
1522 	OPT_STRING('t', "tracer", &ftrace.tracer, "tracer",
1523 		   "Tracer to use: function_graph(default) or function"),
1524 	OPT_CALLBACK_DEFAULT('F', "funcs", NULL, "[FILTER]",
1525 			     "Show available functions to filter",
1526 			     opt_list_avail_functions, "*"),
1527 	OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func",
1528 		     "Trace given functions using function tracer",
1529 		     parse_filter_func),
1530 	OPT_CALLBACK('N', "notrace-funcs", &ftrace.notrace, "func",
1531 		     "Do not trace given functions", parse_filter_func),
1532 	OPT_CALLBACK(0, "func-opts", &ftrace, "options",
1533 		     "Function tracer options, available options: call-graph,irq-info",
1534 		     parse_func_tracer_opts),
1535 	OPT_CALLBACK('G', "graph-funcs", &ftrace.graph_funcs, "func",
1536 		     "Trace given functions using function_graph tracer",
1537 		     parse_filter_func),
1538 	OPT_CALLBACK('g', "nograph-funcs", &ftrace.nograph_funcs, "func",
1539 		     "Set nograph filter on given functions", parse_filter_func),
1540 	OPT_CALLBACK(0, "graph-opts", &ftrace, "options",
1541 		     "Graph tracer options, available options: nosleep-time,noirqs,verbose,thresh=<n>,depth=<n>",
1542 		     parse_graph_tracer_opts),
1543 	OPT_CALLBACK('m', "buffer-size", &ftrace.percpu_buffer_size, "size",
1544 		     "Size of per cpu buffer, needs to use a B, K, M or G suffix.", parse_buffer_size),
1545 	OPT_BOOLEAN(0, "inherit", &ftrace.inherit,
1546 		    "Trace children processes"),
1547 	OPT_INTEGER('D', "delay", &ftrace.target.initial_delay,
1548 		    "Number of milliseconds to wait before starting tracing after program start"),
1549 	OPT_PARENT(common_options),
1550 	};
1551 	const struct option latency_options[] = {
1552 	OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func",
1553 		     "Show latency of given function", parse_filter_func),
1554 #ifdef HAVE_BPF_SKEL
1555 	OPT_BOOLEAN('b', "use-bpf", &ftrace.target.use_bpf,
1556 		    "Use BPF to measure function latency"),
1557 #endif
1558 	OPT_BOOLEAN('n', "use-nsec", &ftrace.use_nsec,
1559 		    "Use nano-second histogram"),
1560 	OPT_PARENT(common_options),
1561 	};
1562 	const struct option profile_options[] = {
1563 	OPT_CALLBACK('T', "trace-funcs", &ftrace.filters, "func",
1564 		     "Trace given functions using function tracer",
1565 		     parse_filter_func),
1566 	OPT_CALLBACK('N', "notrace-funcs", &ftrace.notrace, "func",
1567 		     "Do not trace given functions", parse_filter_func),
1568 	OPT_CALLBACK('G', "graph-funcs", &ftrace.graph_funcs, "func",
1569 		     "Trace given functions using function_graph tracer",
1570 		     parse_filter_func),
1571 	OPT_CALLBACK('g', "nograph-funcs", &ftrace.nograph_funcs, "func",
1572 		     "Set nograph filter on given functions", parse_filter_func),
1573 	OPT_CALLBACK('m', "buffer-size", &ftrace.percpu_buffer_size, "size",
1574 		     "Size of per cpu buffer, needs to use a B, K, M or G suffix.", parse_buffer_size),
1575 	OPT_CALLBACK('s', "sort", &profile_sort, "key",
1576 		     "Sort result by key: total (default), avg, max, count, name.",
1577 		     parse_sort_key),
1578 	OPT_PARENT(common_options),
1579 	};
1580 	const struct option *options = ftrace_options;
1581 
1582 	const char * const ftrace_usage[] = {
1583 		"perf ftrace [<options>] [<command>]",
1584 		"perf ftrace [<options>] -- [<command>] [<options>]",
1585 		"perf ftrace {trace|latency|profile} [<options>] [<command>]",
1586 		"perf ftrace {trace|latency|profile} [<options>] -- [<command>] [<options>]",
1587 		NULL
1588 	};
1589 	enum perf_ftrace_subcommand subcmd = PERF_FTRACE_NONE;
1590 
1591 	INIT_LIST_HEAD(&ftrace.filters);
1592 	INIT_LIST_HEAD(&ftrace.notrace);
1593 	INIT_LIST_HEAD(&ftrace.graph_funcs);
1594 	INIT_LIST_HEAD(&ftrace.nograph_funcs);
1595 
1596 	signal(SIGINT, sig_handler);
1597 	signal(SIGUSR1, sig_handler);
1598 	signal(SIGCHLD, sig_handler);
1599 	signal(SIGPIPE, sig_handler);
1600 
1601 	if (!check_ftrace_capable())
1602 		return -1;
1603 
1604 	if (!is_ftrace_supported()) {
1605 		pr_err("ftrace is not supported on this system\n");
1606 		return -ENOTSUP;
1607 	}
1608 
1609 	ret = perf_config(perf_ftrace_config, &ftrace);
1610 	if (ret < 0)
1611 		return -1;
1612 
1613 	if (argc > 1) {
1614 		if (!strcmp(argv[1], "trace")) {
1615 			subcmd = PERF_FTRACE_TRACE;
1616 		} else if (!strcmp(argv[1], "latency")) {
1617 			subcmd = PERF_FTRACE_LATENCY;
1618 			options = latency_options;
1619 		} else if (!strcmp(argv[1], "profile")) {
1620 			subcmd = PERF_FTRACE_PROFILE;
1621 			options = profile_options;
1622 		}
1623 
1624 		if (subcmd != PERF_FTRACE_NONE) {
1625 			argc--;
1626 			argv++;
1627 		}
1628 	}
1629 	/* for backward compatibility */
1630 	if (subcmd == PERF_FTRACE_NONE)
1631 		subcmd = PERF_FTRACE_TRACE;
1632 
1633 	argc = parse_options(argc, argv, options, ftrace_usage,
1634 			    PARSE_OPT_STOP_AT_NON_OPTION);
1635 	if (argc < 0) {
1636 		ret = -EINVAL;
1637 		goto out_delete_filters;
1638 	}
1639 
1640 	/* Make system wide (-a) the default target. */
1641 	if (!argc && target__none(&ftrace.target))
1642 		ftrace.target.system_wide = true;
1643 
1644 	switch (subcmd) {
1645 	case PERF_FTRACE_TRACE:
1646 		cmd_func = __cmd_ftrace;
1647 		break;
1648 	case PERF_FTRACE_LATENCY:
1649 		if (list_empty(&ftrace.filters)) {
1650 			pr_err("Should provide a function to measure\n");
1651 			parse_options_usage(ftrace_usage, options, "T", 1);
1652 			ret = -EINVAL;
1653 			goto out_delete_filters;
1654 		}
1655 		cmd_func = __cmd_latency;
1656 		break;
1657 	case PERF_FTRACE_PROFILE:
1658 		cmd_func = __cmd_profile;
1659 		break;
1660 	case PERF_FTRACE_NONE:
1661 	default:
1662 		pr_err("Invalid subcommand\n");
1663 		ret = -EINVAL;
1664 		goto out_delete_filters;
1665 	}
1666 
1667 	ret = target__validate(&ftrace.target);
1668 	if (ret) {
1669 		char errbuf[512];
1670 
1671 		target__strerror(&ftrace.target, ret, errbuf, 512);
1672 		pr_err("%s\n", errbuf);
1673 		goto out_delete_filters;
1674 	}
1675 
1676 	ftrace.evlist = evlist__new();
1677 	if (ftrace.evlist == NULL) {
1678 		ret = -ENOMEM;
1679 		goto out_delete_filters;
1680 	}
1681 
1682 	ret = evlist__create_maps(ftrace.evlist, &ftrace.target);
1683 	if (ret < 0)
1684 		goto out_delete_evlist;
1685 
1686 	if (argc) {
1687 		ret = evlist__prepare_workload(ftrace.evlist, &ftrace.target,
1688 					       argv, false,
1689 					       ftrace__workload_exec_failed_signal);
1690 		if (ret < 0)
1691 			goto out_delete_evlist;
1692 	}
1693 
1694 	ret = cmd_func(&ftrace);
1695 
1696 out_delete_evlist:
1697 	evlist__delete(ftrace.evlist);
1698 
1699 out_delete_filters:
1700 	delete_filter_func(&ftrace.filters);
1701 	delete_filter_func(&ftrace.notrace);
1702 	delete_filter_func(&ftrace.graph_funcs);
1703 	delete_filter_func(&ftrace.nograph_funcs);
1704 
1705 	return ret;
1706 }
1707