xref: /linux/tools/perf/builtin-top.c (revision d229807f669ba3dea9f64467ee965051c4366aed)
1 /*
2  * builtin-top.c
3  *
4  * Builtin top command: Display a continuously updated profile of
5  * any workload, CPU or specific PID.
6  *
7  * Copyright (C) 2008, Red Hat Inc, Ingo Molnar <mingo@redhat.com>
8  *		 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
9  *
10  * Improvements and fixes by:
11  *
12  *   Arjan van de Ven <arjan@linux.intel.com>
13  *   Yanmin Zhang <yanmin.zhang@intel.com>
14  *   Wu Fengguang <fengguang.wu@intel.com>
15  *   Mike Galbraith <efault@gmx.de>
16  *   Paul Mackerras <paulus@samba.org>
17  *
18  * Released under the GPL v2. (and only v2, not any later version)
19  */
20 #include "builtin.h"
21 
22 #include "perf.h"
23 
24 #include "util/annotate.h"
25 #include "util/cache.h"
26 #include "util/color.h"
27 #include "util/evlist.h"
28 #include "util/evsel.h"
29 #include "util/session.h"
30 #include "util/symbol.h"
31 #include "util/thread.h"
32 #include "util/thread_map.h"
33 #include "util/top.h"
34 #include "util/util.h"
35 #include <linux/rbtree.h>
36 #include "util/parse-options.h"
37 #include "util/parse-events.h"
38 #include "util/cpumap.h"
39 #include "util/xyarray.h"
40 #include "util/sort.h"
41 
42 #include "util/debug.h"
43 
44 #include <assert.h>
45 #include <fcntl.h>
46 
47 #include <stdio.h>
48 #include <termios.h>
49 #include <unistd.h>
50 #include <inttypes.h>
51 
52 #include <errno.h>
53 #include <time.h>
54 #include <sched.h>
55 
56 #include <sys/syscall.h>
57 #include <sys/ioctl.h>
58 #include <sys/poll.h>
59 #include <sys/prctl.h>
60 #include <sys/wait.h>
61 #include <sys/uio.h>
62 #include <sys/mman.h>
63 
64 #include <linux/unistd.h>
65 #include <linux/types.h>
66 
67 static struct perf_top top = {
68 	.count_filter		= 5,
69 	.delay_secs		= 2,
70 	.target_pid		= -1,
71 	.target_tid		= -1,
72 	.freq			= 1000, /* 1 KHz */
73 };
74 
75 static bool			system_wide			=  false;
76 
77 static bool			use_tui, use_stdio;
78 
79 static bool			sort_has_symbols;
80 
81 static bool			dont_use_callchains;
82 static char			callchain_default_opt[]		= "fractal,0.5,callee";
83 
84 
85 static int			default_interval		=      0;
86 
87 static bool			kptr_restrict_warned;
88 static bool			vmlinux_warned;
89 static bool			inherit				=  false;
90 static int			realtime_prio			=      0;
91 static bool			group				=  false;
92 static unsigned int		mmap_pages			=    128;
93 
94 static bool			dump_symtab                     =  false;
95 
96 static struct winsize		winsize;
97 
98 static const char		*sym_filter			=   NULL;
99 static int			sym_pcnt_filter			=      5;
100 
101 /*
102  * Source functions
103  */
104 
105 void get_term_dimensions(struct winsize *ws)
106 {
107 	char *s = getenv("LINES");
108 
109 	if (s != NULL) {
110 		ws->ws_row = atoi(s);
111 		s = getenv("COLUMNS");
112 		if (s != NULL) {
113 			ws->ws_col = atoi(s);
114 			if (ws->ws_row && ws->ws_col)
115 				return;
116 		}
117 	}
118 #ifdef TIOCGWINSZ
119 	if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
120 	    ws->ws_row && ws->ws_col)
121 		return;
122 #endif
123 	ws->ws_row = 25;
124 	ws->ws_col = 80;
125 }
126 
127 static void update_print_entries(struct winsize *ws)
128 {
129 	top.print_entries = ws->ws_row;
130 
131 	if (top.print_entries > 9)
132 		top.print_entries -= 9;
133 }
134 
135 static void sig_winch_handler(int sig __used)
136 {
137 	get_term_dimensions(&winsize);
138 	update_print_entries(&winsize);
139 }
140 
141 static int parse_source(struct hist_entry *he)
142 {
143 	struct symbol *sym;
144 	struct annotation *notes;
145 	struct map *map;
146 	int err = -1;
147 
148 	if (!he || !he->ms.sym)
149 		return -1;
150 
151 	sym = he->ms.sym;
152 	map = he->ms.map;
153 
154 	/*
155 	 * We can't annotate with just /proc/kallsyms
156 	 */
157 	if (map->dso->symtab_type == SYMTAB__KALLSYMS) {
158 		pr_err("Can't annotate %s: No vmlinux file was found in the "
159 		       "path\n", sym->name);
160 		sleep(1);
161 		return -1;
162 	}
163 
164 	notes = symbol__annotation(sym);
165 	if (notes->src != NULL) {
166 		pthread_mutex_lock(&notes->lock);
167 		goto out_assign;
168 	}
169 
170 	pthread_mutex_lock(&notes->lock);
171 
172 	if (symbol__alloc_hist(sym, top.evlist->nr_entries) < 0) {
173 		pthread_mutex_unlock(&notes->lock);
174 		pr_err("Not enough memory for annotating '%s' symbol!\n",
175 		       sym->name);
176 		sleep(1);
177 		return err;
178 	}
179 
180 	err = symbol__annotate(sym, map, 0);
181 	if (err == 0) {
182 out_assign:
183 		top.sym_filter_entry = he;
184 	}
185 
186 	pthread_mutex_unlock(&notes->lock);
187 	return err;
188 }
189 
190 static void __zero_source_counters(struct hist_entry *he)
191 {
192 	struct symbol *sym = he->ms.sym;
193 	symbol__annotate_zero_histograms(sym);
194 }
195 
196 static void record_precise_ip(struct hist_entry *he, int counter, u64 ip)
197 {
198 	struct annotation *notes;
199 	struct symbol *sym;
200 
201 	if (he == NULL || he->ms.sym == NULL ||
202 	    (he != top.sym_filter_entry && use_browser != 1))
203 		return;
204 
205 	sym = he->ms.sym;
206 	notes = symbol__annotation(sym);
207 
208 	if (pthread_mutex_trylock(&notes->lock))
209 		return;
210 
211 	if (notes->src == NULL &&
212 	    symbol__alloc_hist(sym, top.evlist->nr_entries) < 0) {
213 		pthread_mutex_unlock(&notes->lock);
214 		pr_err("Not enough memory for annotating '%s' symbol!\n",
215 		       sym->name);
216 		sleep(1);
217 		return;
218 	}
219 
220 	ip = he->ms.map->map_ip(he->ms.map, ip);
221 	symbol__inc_addr_samples(sym, he->ms.map, counter, ip);
222 
223 	pthread_mutex_unlock(&notes->lock);
224 }
225 
226 static void show_details(struct hist_entry *he)
227 {
228 	struct annotation *notes;
229 	struct symbol *symbol;
230 	int more;
231 
232 	if (!he)
233 		return;
234 
235 	symbol = he->ms.sym;
236 	notes = symbol__annotation(symbol);
237 
238 	pthread_mutex_lock(&notes->lock);
239 
240 	if (notes->src == NULL)
241 		goto out_unlock;
242 
243 	printf("Showing %s for %s\n", event_name(top.sym_evsel), symbol->name);
244 	printf("  Events  Pcnt (>=%d%%)\n", sym_pcnt_filter);
245 
246 	more = symbol__annotate_printf(symbol, he->ms.map, top.sym_evsel->idx,
247 				       0, sym_pcnt_filter, top.print_entries, 4);
248 	if (top.zero)
249 		symbol__annotate_zero_histogram(symbol, top.sym_evsel->idx);
250 	else
251 		symbol__annotate_decay_histogram(symbol, top.sym_evsel->idx);
252 	if (more != 0)
253 		printf("%d lines not displayed, maybe increase display entries [e]\n", more);
254 out_unlock:
255 	pthread_mutex_unlock(&notes->lock);
256 }
257 
258 static const char		CONSOLE_CLEAR[] = "";
259 
260 static struct hist_entry *
261 	perf_session__add_hist_entry(struct perf_session *session,
262 				     struct addr_location *al,
263 				     struct perf_sample *sample,
264 				     struct perf_evsel *evsel)
265 {
266 	struct hist_entry *he;
267 
268 	he = __hists__add_entry(&evsel->hists, al, NULL, sample->period);
269 	if (he == NULL)
270 		return NULL;
271 
272 	session->hists.stats.total_period += sample->period;
273 	hists__inc_nr_events(&evsel->hists, PERF_RECORD_SAMPLE);
274 	return he;
275 }
276 
277 static void print_sym_table(void)
278 {
279 	char bf[160];
280 	int printed = 0;
281 	const int win_width = winsize.ws_col - 1;
282 
283 	puts(CONSOLE_CLEAR);
284 
285 	perf_top__header_snprintf(&top, bf, sizeof(bf));
286 	printf("%s\n", bf);
287 
288 	perf_top__reset_sample_counters(&top);
289 
290 	printf("%-*.*s\n", win_width, win_width, graph_dotted_line);
291 
292 	if (top.total_lost_warned != top.session->hists.stats.total_lost) {
293 		top.total_lost_warned = top.session->hists.stats.total_lost;
294 		color_fprintf(stdout, PERF_COLOR_RED, "WARNING:");
295 		printf(" LOST %" PRIu64 " events, Check IO/CPU overload\n",
296 		       top.total_lost_warned);
297 		++printed;
298 	}
299 
300 	if (top.sym_filter_entry) {
301 		show_details(top.sym_filter_entry);
302 		return;
303 	}
304 
305 	hists__collapse_resort_threaded(&top.sym_evsel->hists);
306 	hists__output_resort_threaded(&top.sym_evsel->hists);
307 	hists__decay_entries_threaded(&top.sym_evsel->hists,
308 				      top.hide_user_symbols,
309 				      top.hide_kernel_symbols);
310 	hists__output_recalc_col_len(&top.sym_evsel->hists, winsize.ws_row - 3);
311 	putchar('\n');
312 	hists__fprintf(&top.sym_evsel->hists, NULL, false, false,
313 		       winsize.ws_row - 4 - printed, win_width, stdout);
314 }
315 
316 static void prompt_integer(int *target, const char *msg)
317 {
318 	char *buf = malloc(0), *p;
319 	size_t dummy = 0;
320 	int tmp;
321 
322 	fprintf(stdout, "\n%s: ", msg);
323 	if (getline(&buf, &dummy, stdin) < 0)
324 		return;
325 
326 	p = strchr(buf, '\n');
327 	if (p)
328 		*p = 0;
329 
330 	p = buf;
331 	while(*p) {
332 		if (!isdigit(*p))
333 			goto out_free;
334 		p++;
335 	}
336 	tmp = strtoul(buf, NULL, 10);
337 	*target = tmp;
338 out_free:
339 	free(buf);
340 }
341 
342 static void prompt_percent(int *target, const char *msg)
343 {
344 	int tmp = 0;
345 
346 	prompt_integer(&tmp, msg);
347 	if (tmp >= 0 && tmp <= 100)
348 		*target = tmp;
349 }
350 
351 static void prompt_symbol(struct hist_entry **target, const char *msg)
352 {
353 	char *buf = malloc(0), *p;
354 	struct hist_entry *syme = *target, *n, *found = NULL;
355 	struct rb_node *next;
356 	size_t dummy = 0;
357 
358 	/* zero counters of active symbol */
359 	if (syme) {
360 		__zero_source_counters(syme);
361 		*target = NULL;
362 	}
363 
364 	fprintf(stdout, "\n%s: ", msg);
365 	if (getline(&buf, &dummy, stdin) < 0)
366 		goto out_free;
367 
368 	p = strchr(buf, '\n');
369 	if (p)
370 		*p = 0;
371 
372 	next = rb_first(&top.sym_evsel->hists.entries);
373 	while (next) {
374 		n = rb_entry(next, struct hist_entry, rb_node);
375 		if (n->ms.sym && !strcmp(buf, n->ms.sym->name)) {
376 			found = n;
377 			break;
378 		}
379 		next = rb_next(&n->rb_node);
380 	}
381 
382 	if (!found) {
383 		fprintf(stderr, "Sorry, %s is not active.\n", buf);
384 		sleep(1);
385 		return;
386 	} else
387 		parse_source(found);
388 
389 out_free:
390 	free(buf);
391 }
392 
393 static void print_mapped_keys(void)
394 {
395 	char *name = NULL;
396 
397 	if (top.sym_filter_entry) {
398 		struct symbol *sym = top.sym_filter_entry->ms.sym;
399 		name = sym->name;
400 	}
401 
402 	fprintf(stdout, "\nMapped keys:\n");
403 	fprintf(stdout, "\t[d]     display refresh delay.             \t(%d)\n", top.delay_secs);
404 	fprintf(stdout, "\t[e]     display entries (lines).           \t(%d)\n", top.print_entries);
405 
406 	if (top.evlist->nr_entries > 1)
407 		fprintf(stdout, "\t[E]     active event counter.              \t(%s)\n", event_name(top.sym_evsel));
408 
409 	fprintf(stdout, "\t[f]     profile display filter (count).    \t(%d)\n", top.count_filter);
410 
411 	fprintf(stdout, "\t[F]     annotate display filter (percent). \t(%d%%)\n", sym_pcnt_filter);
412 	fprintf(stdout, "\t[s]     annotate symbol.                   \t(%s)\n", name?: "NULL");
413 	fprintf(stdout, "\t[S]     stop annotation.\n");
414 
415 	fprintf(stdout,
416 		"\t[K]     hide kernel_symbols symbols.     \t(%s)\n",
417 		top.hide_kernel_symbols ? "yes" : "no");
418 	fprintf(stdout,
419 		"\t[U]     hide user symbols.               \t(%s)\n",
420 		top.hide_user_symbols ? "yes" : "no");
421 	fprintf(stdout, "\t[z]     toggle sample zeroing.             \t(%d)\n", top.zero ? 1 : 0);
422 	fprintf(stdout, "\t[qQ]    quit.\n");
423 }
424 
425 static int key_mapped(int c)
426 {
427 	switch (c) {
428 		case 'd':
429 		case 'e':
430 		case 'f':
431 		case 'z':
432 		case 'q':
433 		case 'Q':
434 		case 'K':
435 		case 'U':
436 		case 'F':
437 		case 's':
438 		case 'S':
439 			return 1;
440 		case 'E':
441 			return top.evlist->nr_entries > 1 ? 1 : 0;
442 		default:
443 			break;
444 	}
445 
446 	return 0;
447 }
448 
449 static void handle_keypress(int c)
450 {
451 	if (!key_mapped(c)) {
452 		struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
453 		struct termios tc, save;
454 
455 		print_mapped_keys();
456 		fprintf(stdout, "\nEnter selection, or unmapped key to continue: ");
457 		fflush(stdout);
458 
459 		tcgetattr(0, &save);
460 		tc = save;
461 		tc.c_lflag &= ~(ICANON | ECHO);
462 		tc.c_cc[VMIN] = 0;
463 		tc.c_cc[VTIME] = 0;
464 		tcsetattr(0, TCSANOW, &tc);
465 
466 		poll(&stdin_poll, 1, -1);
467 		c = getc(stdin);
468 
469 		tcsetattr(0, TCSAFLUSH, &save);
470 		if (!key_mapped(c))
471 			return;
472 	}
473 
474 	switch (c) {
475 		case 'd':
476 			prompt_integer(&top.delay_secs, "Enter display delay");
477 			if (top.delay_secs < 1)
478 				top.delay_secs = 1;
479 			break;
480 		case 'e':
481 			prompt_integer(&top.print_entries, "Enter display entries (lines)");
482 			if (top.print_entries == 0) {
483 				sig_winch_handler(SIGWINCH);
484 				signal(SIGWINCH, sig_winch_handler);
485 			} else
486 				signal(SIGWINCH, SIG_DFL);
487 			break;
488 		case 'E':
489 			if (top.evlist->nr_entries > 1) {
490 				/* Select 0 as the default event: */
491 				int counter = 0;
492 
493 				fprintf(stderr, "\nAvailable events:");
494 
495 				list_for_each_entry(top.sym_evsel, &top.evlist->entries, node)
496 					fprintf(stderr, "\n\t%d %s", top.sym_evsel->idx, event_name(top.sym_evsel));
497 
498 				prompt_integer(&counter, "Enter details event counter");
499 
500 				if (counter >= top.evlist->nr_entries) {
501 					top.sym_evsel = list_entry(top.evlist->entries.next, struct perf_evsel, node);
502 					fprintf(stderr, "Sorry, no such event, using %s.\n", event_name(top.sym_evsel));
503 					sleep(1);
504 					break;
505 				}
506 				list_for_each_entry(top.sym_evsel, &top.evlist->entries, node)
507 					if (top.sym_evsel->idx == counter)
508 						break;
509 			} else
510 				top.sym_evsel = list_entry(top.evlist->entries.next, struct perf_evsel, node);
511 			break;
512 		case 'f':
513 			prompt_integer(&top.count_filter, "Enter display event count filter");
514 			break;
515 		case 'F':
516 			prompt_percent(&sym_pcnt_filter, "Enter details display event filter (percent)");
517 			break;
518 		case 'K':
519 			top.hide_kernel_symbols = !top.hide_kernel_symbols;
520 			break;
521 		case 'q':
522 		case 'Q':
523 			printf("exiting.\n");
524 			if (dump_symtab)
525 				perf_session__fprintf_dsos(top.session, stderr);
526 			exit(0);
527 		case 's':
528 			prompt_symbol(&top.sym_filter_entry, "Enter details symbol");
529 			break;
530 		case 'S':
531 			if (!top.sym_filter_entry)
532 				break;
533 			else {
534 				struct hist_entry *syme = top.sym_filter_entry;
535 
536 				top.sym_filter_entry = NULL;
537 				__zero_source_counters(syme);
538 			}
539 			break;
540 		case 'U':
541 			top.hide_user_symbols = !top.hide_user_symbols;
542 			break;
543 		case 'z':
544 			top.zero = !top.zero;
545 			break;
546 		default:
547 			break;
548 	}
549 }
550 
551 static void perf_top__sort_new_samples(void *arg)
552 {
553 	struct perf_top *t = arg;
554 	perf_top__reset_sample_counters(t);
555 
556 	if (t->evlist->selected != NULL)
557 		t->sym_evsel = t->evlist->selected;
558 
559 	hists__collapse_resort_threaded(&t->sym_evsel->hists);
560 	hists__output_resort_threaded(&t->sym_evsel->hists);
561 	hists__decay_entries_threaded(&t->sym_evsel->hists,
562 				      top.hide_user_symbols,
563 				      top.hide_kernel_symbols);
564 	hists__output_recalc_col_len(&t->sym_evsel->hists, winsize.ws_row - 3);
565 }
566 
567 static void *display_thread_tui(void *arg __used)
568 {
569 	const char *help = "For a higher level overview, try: perf top --sort comm,dso";
570 
571 	perf_top__sort_new_samples(&top);
572 	perf_evlist__tui_browse_hists(top.evlist, help,
573 				      perf_top__sort_new_samples,
574 				      &top, top.delay_secs);
575 
576 	exit_browser(0);
577 	exit(0);
578 	return NULL;
579 }
580 
581 static void *display_thread(void *arg __used)
582 {
583 	struct pollfd stdin_poll = { .fd = 0, .events = POLLIN };
584 	struct termios tc, save;
585 	int delay_msecs, c;
586 
587 	tcgetattr(0, &save);
588 	tc = save;
589 	tc.c_lflag &= ~(ICANON | ECHO);
590 	tc.c_cc[VMIN] = 0;
591 	tc.c_cc[VTIME] = 0;
592 
593 	pthread__unblock_sigwinch();
594 repeat:
595 	delay_msecs = top.delay_secs * 1000;
596 	tcsetattr(0, TCSANOW, &tc);
597 	/* trash return*/
598 	getc(stdin);
599 
600 	while (1) {
601 		print_sym_table();
602 		/*
603 		 * Either timeout expired or we got an EINTR due to SIGWINCH,
604 		 * refresh screen in both cases.
605 		 */
606 		switch (poll(&stdin_poll, 1, delay_msecs)) {
607 		case 0:
608 			continue;
609 		case -1:
610 			if (errno == EINTR)
611 				continue;
612 			/* Fall trhu */
613 		default:
614 			goto process_hotkey;
615 		}
616 	}
617 process_hotkey:
618 	c = getc(stdin);
619 	tcsetattr(0, TCSAFLUSH, &save);
620 
621 	handle_keypress(c);
622 	goto repeat;
623 
624 	return NULL;
625 }
626 
627 /* Tag samples to be skipped. */
628 static const char *skip_symbols[] = {
629 	"default_idle",
630 	"native_safe_halt",
631 	"cpu_idle",
632 	"enter_idle",
633 	"exit_idle",
634 	"mwait_idle",
635 	"mwait_idle_with_hints",
636 	"poll_idle",
637 	"ppc64_runlatch_off",
638 	"pseries_dedicated_idle_sleep",
639 	NULL
640 };
641 
642 static int symbol_filter(struct map *map __used, struct symbol *sym)
643 {
644 	const char *name = sym->name;
645 	int i;
646 
647 	/*
648 	 * ppc64 uses function descriptors and appends a '.' to the
649 	 * start of every instruction address. Remove it.
650 	 */
651 	if (name[0] == '.')
652 		name++;
653 
654 	if (!strcmp(name, "_text") ||
655 	    !strcmp(name, "_etext") ||
656 	    !strcmp(name, "_sinittext") ||
657 	    !strncmp("init_module", name, 11) ||
658 	    !strncmp("cleanup_module", name, 14) ||
659 	    strstr(name, "_text_start") ||
660 	    strstr(name, "_text_end"))
661 		return 1;
662 
663 	for (i = 0; skip_symbols[i]; i++) {
664 		if (!strcmp(skip_symbols[i], name)) {
665 			sym->ignore = true;
666 			break;
667 		}
668 	}
669 
670 	return 0;
671 }
672 
673 static void perf_event__process_sample(const union perf_event *event,
674 				       struct perf_sample *sample,
675 				       struct perf_session *session)
676 {
677 	struct symbol *parent = NULL;
678 	u64 ip = event->ip.ip;
679 	struct addr_location al;
680 	struct machine *machine;
681 	int err;
682 	u8 origin = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
683 
684 	++top.samples;
685 
686 	switch (origin) {
687 	case PERF_RECORD_MISC_USER:
688 		++top.us_samples;
689 		if (top.hide_user_symbols)
690 			return;
691 		machine = perf_session__find_host_machine(session);
692 		break;
693 	case PERF_RECORD_MISC_KERNEL:
694 		++top.kernel_samples;
695 		if (top.hide_kernel_symbols)
696 			return;
697 		machine = perf_session__find_host_machine(session);
698 		break;
699 	case PERF_RECORD_MISC_GUEST_KERNEL:
700 		++top.guest_kernel_samples;
701 		machine = perf_session__find_machine(session, event->ip.pid);
702 		break;
703 	case PERF_RECORD_MISC_GUEST_USER:
704 		++top.guest_us_samples;
705 		/*
706 		 * TODO: we don't process guest user from host side
707 		 * except simple counting.
708 		 */
709 		return;
710 	default:
711 		return;
712 	}
713 
714 	if (!machine && perf_guest) {
715 		pr_err("Can't find guest [%d]'s kernel information\n",
716 			event->ip.pid);
717 		return;
718 	}
719 
720 	if (event->header.misc & PERF_RECORD_MISC_EXACT_IP)
721 		top.exact_samples++;
722 
723 	if (perf_event__preprocess_sample(event, session, &al, sample,
724 					  symbol_filter) < 0 ||
725 	    al.filtered)
726 		return;
727 
728 	if (!kptr_restrict_warned &&
729 	    symbol_conf.kptr_restrict &&
730 	    al.cpumode == PERF_RECORD_MISC_KERNEL) {
731 		ui__warning(
732 "Kernel address maps (/proc/{kallsyms,modules}) are restricted.\n\n"
733 "Check /proc/sys/kernel/kptr_restrict.\n\n"
734 "Kernel%s samples will not be resolved.\n",
735 			  !RB_EMPTY_ROOT(&al.map->dso->symbols[MAP__FUNCTION]) ?
736 			  " modules" : "");
737 		if (use_browser <= 0)
738 			sleep(5);
739 		kptr_restrict_warned = true;
740 	}
741 
742 	if (al.sym == NULL) {
743 		const char *msg = "Kernel samples will not be resolved.\n";
744 		/*
745 		 * As we do lazy loading of symtabs we only will know if the
746 		 * specified vmlinux file is invalid when we actually have a
747 		 * hit in kernel space and then try to load it. So if we get
748 		 * here and there are _no_ symbols in the DSO backing the
749 		 * kernel map, bail out.
750 		 *
751 		 * We may never get here, for instance, if we use -K/
752 		 * --hide-kernel-symbols, even if the user specifies an
753 		 * invalid --vmlinux ;-)
754 		 */
755 		if (!kptr_restrict_warned && !vmlinux_warned &&
756 		    al.map == machine->vmlinux_maps[MAP__FUNCTION] &&
757 		    RB_EMPTY_ROOT(&al.map->dso->symbols[MAP__FUNCTION])) {
758 			if (symbol_conf.vmlinux_name) {
759 				ui__warning("The %s file can't be used.\n%s",
760 					    symbol_conf.vmlinux_name, msg);
761 			} else {
762 				ui__warning("A vmlinux file was not found.\n%s",
763 					    msg);
764 			}
765 
766 			if (use_browser <= 0)
767 				sleep(5);
768 			vmlinux_warned = true;
769 		}
770 	}
771 
772 	if (al.sym == NULL || !al.sym->ignore) {
773 		struct perf_evsel *evsel;
774 		struct hist_entry *he;
775 
776 		evsel = perf_evlist__id2evsel(top.evlist, sample->id);
777 		assert(evsel != NULL);
778 
779 		if ((sort__has_parent || symbol_conf.use_callchain) &&
780 		    sample->callchain) {
781 			err = perf_session__resolve_callchain(session, al.thread,
782 							      sample->callchain, &parent);
783 			if (err)
784 				return;
785 		}
786 
787 		he = perf_session__add_hist_entry(session, &al, sample, evsel);
788 		if (he == NULL) {
789 			pr_err("Problem incrementing symbol period, skipping event\n");
790 			return;
791 		}
792 
793 		if (symbol_conf.use_callchain) {
794 			err = callchain_append(he->callchain, &session->callchain_cursor,
795 					       sample->period);
796 			if (err)
797 				return;
798 		}
799 
800 		if (sort_has_symbols)
801 			record_precise_ip(he, evsel->idx, ip);
802 	}
803 
804 	return;
805 }
806 
807 static void perf_session__mmap_read_idx(struct perf_session *self, int idx)
808 {
809 	struct perf_sample sample;
810 	union perf_event *event;
811 	int ret;
812 
813 	while ((event = perf_evlist__mmap_read(top.evlist, idx)) != NULL) {
814 		ret = perf_session__parse_sample(self, event, &sample);
815 		if (ret) {
816 			pr_err("Can't parse sample, err = %d\n", ret);
817 			continue;
818 		}
819 
820 		if (event->header.type == PERF_RECORD_SAMPLE)
821 			perf_event__process_sample(event, &sample, self);
822 		else
823 			perf_event__process(event, &sample, self);
824 	}
825 }
826 
827 static void perf_session__mmap_read(struct perf_session *self)
828 {
829 	int i;
830 
831 	for (i = 0; i < top.evlist->nr_mmaps; i++)
832 		perf_session__mmap_read_idx(self, i);
833 }
834 
835 static void start_counters(struct perf_evlist *evlist)
836 {
837 	struct perf_evsel *counter;
838 
839 	list_for_each_entry(counter, &evlist->entries, node) {
840 		struct perf_event_attr *attr = &counter->attr;
841 
842 		attr->sample_type = PERF_SAMPLE_IP | PERF_SAMPLE_TID;
843 
844 		if (top.freq) {
845 			attr->sample_type |= PERF_SAMPLE_PERIOD;
846 			attr->freq	  = 1;
847 			attr->sample_freq = top.freq;
848 		}
849 
850 		if (evlist->nr_entries > 1) {
851 			attr->sample_type |= PERF_SAMPLE_ID;
852 			attr->read_format |= PERF_FORMAT_ID;
853 		}
854 
855 		if (symbol_conf.use_callchain)
856 			attr->sample_type |= PERF_SAMPLE_CALLCHAIN;
857 
858 		attr->mmap = 1;
859 		attr->comm = 1;
860 		attr->inherit = inherit;
861 try_again:
862 		if (perf_evsel__open(counter, top.evlist->cpus,
863 				     top.evlist->threads, group) < 0) {
864 			int err = errno;
865 
866 			if (err == EPERM || err == EACCES) {
867 				ui__warning_paranoid();
868 				goto out_err;
869 			}
870 			/*
871 			 * If it's cycles then fall back to hrtimer
872 			 * based cpu-clock-tick sw counter, which
873 			 * is always available even if no PMU support:
874 			 */
875 			if (attr->type == PERF_TYPE_HARDWARE &&
876 			    attr->config == PERF_COUNT_HW_CPU_CYCLES) {
877 				if (verbose)
878 					ui__warning("Cycles event not supported,\n"
879 						    "trying to fall back to cpu-clock-ticks\n");
880 
881 				attr->type = PERF_TYPE_SOFTWARE;
882 				attr->config = PERF_COUNT_SW_CPU_CLOCK;
883 				goto try_again;
884 			}
885 
886 			if (err == ENOENT) {
887 				ui__warning("The %s event is not supported.\n",
888 					    event_name(counter));
889 				goto out_err;
890 			}
891 
892 			ui__warning("The sys_perf_event_open() syscall "
893 				    "returned with %d (%s).  /bin/dmesg "
894 				    "may provide additional information.\n"
895 				    "No CONFIG_PERF_EVENTS=y kernel support "
896 				    "configured?\n", err, strerror(err));
897 			goto out_err;
898 		}
899 	}
900 
901 	if (perf_evlist__mmap(evlist, mmap_pages, false) < 0) {
902 		ui__warning("Failed to mmap with %d (%s)\n",
903 			    errno, strerror(errno));
904 		goto out_err;
905 	}
906 
907 	return;
908 
909 out_err:
910 	exit_browser(0);
911 	exit(0);
912 }
913 
914 static int setup_sample_type(void)
915 {
916 	if (!sort_has_symbols) {
917 		if (symbol_conf.use_callchain) {
918 			ui__warning("Selected -g but \"sym\" not present in --sort/-s.");
919 			return -EINVAL;
920 		}
921 	} else if (!dont_use_callchains && callchain_param.mode != CHAIN_NONE) {
922 		if (callchain_register_param(&callchain_param) < 0) {
923 			ui__warning("Can't register callchain params.\n");
924 			return -EINVAL;
925 		}
926 	}
927 
928 	return 0;
929 }
930 
931 static int __cmd_top(void)
932 {
933 	pthread_t thread;
934 	int ret;
935 	/*
936 	 * FIXME: perf_session__new should allow passing a O_MMAP, so that all this
937 	 * mmap reading, etc is encapsulated in it. Use O_WRONLY for now.
938 	 */
939 	top.session = perf_session__new(NULL, O_WRONLY, false, false, NULL);
940 	if (top.session == NULL)
941 		return -ENOMEM;
942 
943 	ret = setup_sample_type();
944 	if (ret)
945 		goto out_delete;
946 
947 	if (top.target_tid != -1)
948 		perf_event__synthesize_thread_map(top.evlist->threads,
949 						  perf_event__process, top.session);
950 	else
951 		perf_event__synthesize_threads(perf_event__process, top.session);
952 
953 	start_counters(top.evlist);
954 	top.session->evlist = top.evlist;
955 	perf_session__update_sample_type(top.session);
956 
957 	/* Wait for a minimal set of events before starting the snapshot */
958 	poll(top.evlist->pollfd, top.evlist->nr_fds, 100);
959 
960 	perf_session__mmap_read(top.session);
961 
962 	if (pthread_create(&thread, NULL, (use_browser > 0 ? display_thread_tui :
963 							     display_thread), NULL)) {
964 		printf("Could not create display thread.\n");
965 		exit(-1);
966 	}
967 
968 	if (realtime_prio) {
969 		struct sched_param param;
970 
971 		param.sched_priority = realtime_prio;
972 		if (sched_setscheduler(0, SCHED_FIFO, &param)) {
973 			printf("Could not set realtime priority.\n");
974 			exit(-1);
975 		}
976 	}
977 
978 	while (1) {
979 		u64 hits = top.samples;
980 
981 		perf_session__mmap_read(top.session);
982 
983 		if (hits == top.samples)
984 			ret = poll(top.evlist->pollfd, top.evlist->nr_fds, 100);
985 	}
986 
987 out_delete:
988 	perf_session__delete(top.session);
989 	top.session = NULL;
990 
991 	return 0;
992 }
993 
994 static int
995 parse_callchain_opt(const struct option *opt __used, const char *arg,
996 		    int unset)
997 {
998 	char *tok, *tok2;
999 	char *endptr;
1000 
1001 	/*
1002 	 * --no-call-graph
1003 	 */
1004 	if (unset) {
1005 		dont_use_callchains = true;
1006 		return 0;
1007 	}
1008 
1009 	symbol_conf.use_callchain = true;
1010 
1011 	if (!arg)
1012 		return 0;
1013 
1014 	tok = strtok((char *)arg, ",");
1015 	if (!tok)
1016 		return -1;
1017 
1018 	/* get the output mode */
1019 	if (!strncmp(tok, "graph", strlen(arg)))
1020 		callchain_param.mode = CHAIN_GRAPH_ABS;
1021 
1022 	else if (!strncmp(tok, "flat", strlen(arg)))
1023 		callchain_param.mode = CHAIN_FLAT;
1024 
1025 	else if (!strncmp(tok, "fractal", strlen(arg)))
1026 		callchain_param.mode = CHAIN_GRAPH_REL;
1027 
1028 	else if (!strncmp(tok, "none", strlen(arg))) {
1029 		callchain_param.mode = CHAIN_NONE;
1030 		symbol_conf.use_callchain = false;
1031 
1032 		return 0;
1033 	}
1034 
1035 	else
1036 		return -1;
1037 
1038 	/* get the min percentage */
1039 	tok = strtok(NULL, ",");
1040 	if (!tok)
1041 		goto setup;
1042 
1043 	callchain_param.min_percent = strtod(tok, &endptr);
1044 	if (tok == endptr)
1045 		return -1;
1046 
1047 	/* get the print limit */
1048 	tok2 = strtok(NULL, ",");
1049 	if (!tok2)
1050 		goto setup;
1051 
1052 	if (tok2[0] != 'c') {
1053 		callchain_param.print_limit = strtod(tok2, &endptr);
1054 		tok2 = strtok(NULL, ",");
1055 		if (!tok2)
1056 			goto setup;
1057 	}
1058 
1059 	/* get the call chain order */
1060 	if (!strcmp(tok2, "caller"))
1061 		callchain_param.order = ORDER_CALLER;
1062 	else if (!strcmp(tok2, "callee"))
1063 		callchain_param.order = ORDER_CALLEE;
1064 	else
1065 		return -1;
1066 setup:
1067 	if (callchain_register_param(&callchain_param) < 0) {
1068 		fprintf(stderr, "Can't register callchain params\n");
1069 		return -1;
1070 	}
1071 	return 0;
1072 }
1073 
1074 static const char * const top_usage[] = {
1075 	"perf top [<options>]",
1076 	NULL
1077 };
1078 
1079 static const struct option options[] = {
1080 	OPT_CALLBACK('e', "event", &top.evlist, "event",
1081 		     "event selector. use 'perf list' to list available events",
1082 		     parse_events_option),
1083 	OPT_INTEGER('c', "count", &default_interval,
1084 		    "event period to sample"),
1085 	OPT_INTEGER('p', "pid", &top.target_pid,
1086 		    "profile events on existing process id"),
1087 	OPT_INTEGER('t', "tid", &top.target_tid,
1088 		    "profile events on existing thread id"),
1089 	OPT_BOOLEAN('a', "all-cpus", &system_wide,
1090 			    "system-wide collection from all CPUs"),
1091 	OPT_STRING('C', "cpu", &top.cpu_list, "cpu",
1092 		    "list of cpus to monitor"),
1093 	OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
1094 		   "file", "vmlinux pathname"),
1095 	OPT_BOOLEAN('K', "hide_kernel_symbols", &top.hide_kernel_symbols,
1096 		    "hide kernel symbols"),
1097 	OPT_UINTEGER('m', "mmap-pages", &mmap_pages, "number of mmap data pages"),
1098 	OPT_INTEGER('r', "realtime", &realtime_prio,
1099 		    "collect data with this RT SCHED_FIFO priority"),
1100 	OPT_INTEGER('d', "delay", &top.delay_secs,
1101 		    "number of seconds to delay between refreshes"),
1102 	OPT_BOOLEAN('D', "dump-symtab", &dump_symtab,
1103 			    "dump the symbol table used for profiling"),
1104 	OPT_INTEGER('f', "count-filter", &top.count_filter,
1105 		    "only display functions with more events than this"),
1106 	OPT_BOOLEAN('g', "group", &group,
1107 			    "put the counters into a counter group"),
1108 	OPT_BOOLEAN('i', "inherit", &inherit,
1109 		    "child tasks inherit counters"),
1110 	OPT_STRING(0, "sym-annotate", &sym_filter, "symbol name",
1111 		    "symbol to annotate"),
1112 	OPT_BOOLEAN('z', "zero", &top.zero,
1113 		    "zero history across updates"),
1114 	OPT_INTEGER('F', "freq", &top.freq,
1115 		    "profile at this frequency"),
1116 	OPT_INTEGER('E', "entries", &top.print_entries,
1117 		    "display this many functions"),
1118 	OPT_BOOLEAN('U', "hide_user_symbols", &top.hide_user_symbols,
1119 		    "hide user symbols"),
1120 	OPT_BOOLEAN(0, "tui", &use_tui, "Use the TUI interface"),
1121 	OPT_BOOLEAN(0, "stdio", &use_stdio, "Use the stdio interface"),
1122 	OPT_INCR('v', "verbose", &verbose,
1123 		    "be more verbose (show counter open errors, etc)"),
1124 	OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
1125 		   "sort by key(s): pid, comm, dso, symbol, parent"),
1126 	OPT_BOOLEAN('n', "show-nr-samples", &symbol_conf.show_nr_samples,
1127 		    "Show a column with the number of samples"),
1128 	OPT_CALLBACK_DEFAULT('G', "call-graph", NULL, "output_type,min_percent, call_order",
1129 		     "Display callchains using output_type (graph, flat, fractal, or none), min percent threshold and callchain order. "
1130 		     "Default: fractal,0.5,callee", &parse_callchain_opt,
1131 		     callchain_default_opt),
1132 	OPT_BOOLEAN(0, "show-total-period", &symbol_conf.show_total_period,
1133 		    "Show a column with the sum of periods"),
1134 	OPT_STRING(0, "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
1135 		   "only consider symbols in these dsos"),
1136 	OPT_STRING(0, "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
1137 		   "only consider symbols in these comms"),
1138 	OPT_STRING(0, "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
1139 		   "only consider these symbols"),
1140 	OPT_BOOLEAN(0, "source", &symbol_conf.annotate_src,
1141 		    "Interleave source code with assembly code (default)"),
1142 	OPT_BOOLEAN(0, "asm-raw", &symbol_conf.annotate_asm_raw,
1143 		    "Display raw encoding of assembly instructions (default)"),
1144 	OPT_STRING('M', "disassembler-style", &disassembler_style, "disassembler style",
1145 		   "Specify disassembler style (e.g. -M intel for intel syntax)"),
1146 	OPT_END()
1147 };
1148 
1149 int cmd_top(int argc, const char **argv, const char *prefix __used)
1150 {
1151 	struct perf_evsel *pos;
1152 	int status = -ENOMEM;
1153 
1154 	top.evlist = perf_evlist__new(NULL, NULL);
1155 	if (top.evlist == NULL)
1156 		return -ENOMEM;
1157 
1158 	symbol_conf.exclude_other = false;
1159 
1160 	argc = parse_options(argc, argv, options, top_usage, 0);
1161 	if (argc)
1162 		usage_with_options(top_usage, options);
1163 
1164 	if (sort_order == default_sort_order)
1165 		sort_order = "dso,symbol";
1166 
1167 	setup_sorting(top_usage, options);
1168 
1169 	if (use_stdio)
1170 		use_browser = 0;
1171 	else if (use_tui)
1172 		use_browser = 1;
1173 
1174 	setup_browser(false);
1175 
1176 	/* CPU and PID are mutually exclusive */
1177 	if (top.target_tid > 0 && top.cpu_list) {
1178 		printf("WARNING: PID switch overriding CPU\n");
1179 		sleep(1);
1180 		top.cpu_list = NULL;
1181 	}
1182 
1183 	if (top.target_pid != -1)
1184 		top.target_tid = top.target_pid;
1185 
1186 	if (perf_evlist__create_maps(top.evlist, top.target_pid,
1187 				     top.target_tid, top.cpu_list) < 0)
1188 		usage_with_options(top_usage, options);
1189 
1190 	if (!top.evlist->nr_entries &&
1191 	    perf_evlist__add_default(top.evlist) < 0) {
1192 		pr_err("Not enough memory for event selector list\n");
1193 		return -ENOMEM;
1194 	}
1195 
1196 	if (top.delay_secs < 1)
1197 		top.delay_secs = 1;
1198 
1199 	/*
1200 	 * User specified count overrides default frequency.
1201 	 */
1202 	if (default_interval)
1203 		top.freq = 0;
1204 	else if (top.freq) {
1205 		default_interval = top.freq;
1206 	} else {
1207 		fprintf(stderr, "frequency and count are zero, aborting\n");
1208 		exit(EXIT_FAILURE);
1209 	}
1210 
1211 	list_for_each_entry(pos, &top.evlist->entries, node) {
1212 		if (perf_evsel__alloc_fd(pos, top.evlist->cpus->nr,
1213 					 top.evlist->threads->nr) < 0)
1214 			goto out_free_fd;
1215 		/*
1216 		 * Fill in the ones not specifically initialized via -c:
1217 		 */
1218 		if (pos->attr.sample_period)
1219 			continue;
1220 
1221 		pos->attr.sample_period = default_interval;
1222 	}
1223 
1224 	if (perf_evlist__alloc_pollfd(top.evlist) < 0 ||
1225 	    perf_evlist__alloc_mmap(top.evlist) < 0)
1226 		goto out_free_fd;
1227 
1228 	top.sym_evsel = list_entry(top.evlist->entries.next, struct perf_evsel, node);
1229 
1230 	symbol_conf.priv_size = sizeof(struct annotation);
1231 
1232 	symbol_conf.try_vmlinux_path = (symbol_conf.vmlinux_name == NULL);
1233 	if (symbol__init() < 0)
1234 		return -1;
1235 
1236 	sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", stdout);
1237 	sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", stdout);
1238 	sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", stdout);
1239 
1240 	/*
1241 	 * Avoid annotation data structures overhead when symbols aren't on the
1242 	 * sort list.
1243 	 */
1244 	sort_has_symbols = sort_sym.list.next != NULL;
1245 
1246 	get_term_dimensions(&winsize);
1247 	if (top.print_entries == 0) {
1248 		update_print_entries(&winsize);
1249 		signal(SIGWINCH, sig_winch_handler);
1250 	}
1251 
1252 	status = __cmd_top();
1253 out_free_fd:
1254 	perf_evlist__delete(top.evlist);
1255 
1256 	return status;
1257 }
1258