xref: /openbmc/linux/tools/perf/builtin-annotate.c (revision 93707cbabcc8baf2b2b5f4a99c1f08ee83eb7abd)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * builtin-annotate.c
4  *
5  * Builtin annotate command: Analyze the perf.data input file,
6  * look up and read DSOs and symbol information and display
7  * a histogram of results, along various sorting keys.
8  */
9 #include "builtin.h"
10 
11 #include "util/util.h"
12 #include "util/color.h"
13 #include <linux/list.h>
14 #include "util/cache.h"
15 #include <linux/rbtree.h>
16 #include "util/symbol.h"
17 
18 #include "perf.h"
19 #include "util/debug.h"
20 
21 #include "util/evlist.h"
22 #include "util/evsel.h"
23 #include "util/annotate.h"
24 #include "util/event.h"
25 #include <subcmd/parse-options.h>
26 #include "util/parse-events.h"
27 #include "util/thread.h"
28 #include "util/sort.h"
29 #include "util/hist.h"
30 #include "util/session.h"
31 #include "util/tool.h"
32 #include "util/data.h"
33 #include "arch/common.h"
34 #include "util/block-range.h"
35 
36 #include <dlfcn.h>
37 #include <errno.h>
38 #include <linux/bitmap.h>
39 
40 struct perf_annotate {
41 	struct perf_tool tool;
42 	struct perf_session *session;
43 	bool	   use_tui, use_stdio, use_gtk;
44 	bool	   full_paths;
45 	bool	   print_line;
46 	bool	   skip_missing;
47 	const char *sym_hist_filter;
48 	const char *cpu_list;
49 	DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
50 };
51 
52 /*
53  * Given one basic block:
54  *
55  *	from	to		branch_i
56  *	* ----> *
57  *		|
58  *		| block
59  *		v
60  *		* ----> *
61  *		from	to	branch_i+1
62  *
63  * where the horizontal are the branches and the vertical is the executed
64  * block of instructions.
65  *
66  * We count, for each 'instruction', the number of blocks that covered it as
67  * well as count the ratio each branch is taken.
68  *
69  * We can do this without knowing the actual instruction stream by keeping
70  * track of the address ranges. We break down ranges such that there is no
71  * overlap and iterate from the start until the end.
72  *
73  * @acme: once we parse the objdump output _before_ processing the samples,
74  * we can easily fold the branch.cycles IPC bits in.
75  */
76 static void process_basic_block(struct addr_map_symbol *start,
77 				struct addr_map_symbol *end,
78 				struct branch_flags *flags)
79 {
80 	struct symbol *sym = start->sym;
81 	struct annotation *notes = sym ? symbol__annotation(sym) : NULL;
82 	struct block_range_iter iter;
83 	struct block_range *entry;
84 
85 	/*
86 	 * Sanity; NULL isn't executable and the CPU cannot execute backwards
87 	 */
88 	if (!start->addr || start->addr > end->addr)
89 		return;
90 
91 	iter = block_range__create(start->addr, end->addr);
92 	if (!block_range_iter__valid(&iter))
93 		return;
94 
95 	/*
96 	 * First block in range is a branch target.
97 	 */
98 	entry = block_range_iter(&iter);
99 	assert(entry->is_target);
100 	entry->entry++;
101 
102 	do {
103 		entry = block_range_iter(&iter);
104 
105 		entry->coverage++;
106 		entry->sym = sym;
107 
108 		if (notes)
109 			notes->max_coverage = max(notes->max_coverage, entry->coverage);
110 
111 	} while (block_range_iter__next(&iter));
112 
113 	/*
114 	 * Last block in rage is a branch.
115 	 */
116 	entry = block_range_iter(&iter);
117 	assert(entry->is_branch);
118 	entry->taken++;
119 	if (flags->predicted)
120 		entry->pred++;
121 }
122 
123 static void process_branch_stack(struct branch_stack *bs, struct addr_location *al,
124 				 struct perf_sample *sample)
125 {
126 	struct addr_map_symbol *prev = NULL;
127 	struct branch_info *bi;
128 	int i;
129 
130 	if (!bs || !bs->nr)
131 		return;
132 
133 	bi = sample__resolve_bstack(sample, al);
134 	if (!bi)
135 		return;
136 
137 	for (i = bs->nr - 1; i >= 0; i--) {
138 		/*
139 		 * XXX filter against symbol
140 		 */
141 		if (prev)
142 			process_basic_block(prev, &bi[i].from, &bi[i].flags);
143 		prev = &bi[i].to;
144 	}
145 
146 	free(bi);
147 }
148 
149 static int perf_evsel__add_sample(struct perf_evsel *evsel,
150 				  struct perf_sample *sample,
151 				  struct addr_location *al,
152 				  struct perf_annotate *ann)
153 {
154 	struct hists *hists = evsel__hists(evsel);
155 	struct hist_entry *he;
156 	int ret;
157 
158 	if (ann->sym_hist_filter != NULL &&
159 	    (al->sym == NULL ||
160 	     strcmp(ann->sym_hist_filter, al->sym->name) != 0)) {
161 		/* We're only interested in a symbol named sym_hist_filter */
162 		/*
163 		 * FIXME: why isn't this done in the symbol_filter when loading
164 		 * the DSO?
165 		 */
166 		if (al->sym != NULL) {
167 			rb_erase(&al->sym->rb_node,
168 				 &al->map->dso->symbols[al->map->type]);
169 			symbol__delete(al->sym);
170 			dso__reset_find_symbol_cache(al->map->dso);
171 		}
172 		return 0;
173 	}
174 
175 	/*
176 	 * XXX filtered samples can still have branch entires pointing into our
177 	 * symbol and are missed.
178 	 */
179 	process_branch_stack(sample->branch_stack, al, sample);
180 
181 	he = hists__add_entry(hists, al, NULL, NULL, NULL, sample, true);
182 	if (he == NULL)
183 		return -ENOMEM;
184 
185 	ret = hist_entry__inc_addr_samples(he, sample, evsel->idx, al->addr);
186 	hists__inc_nr_samples(hists, true);
187 	return ret;
188 }
189 
190 static int process_sample_event(struct perf_tool *tool,
191 				union perf_event *event,
192 				struct perf_sample *sample,
193 				struct perf_evsel *evsel,
194 				struct machine *machine)
195 {
196 	struct perf_annotate *ann = container_of(tool, struct perf_annotate, tool);
197 	struct addr_location al;
198 	int ret = 0;
199 
200 	if (machine__resolve(machine, &al, sample) < 0) {
201 		pr_warning("problem processing %d event, skipping it.\n",
202 			   event->header.type);
203 		return -1;
204 	}
205 
206 	if (ann->cpu_list && !test_bit(sample->cpu, ann->cpu_bitmap))
207 		goto out_put;
208 
209 	if (!al.filtered && perf_evsel__add_sample(evsel, sample, &al, ann)) {
210 		pr_warning("problem incrementing symbol count, "
211 			   "skipping event\n");
212 		ret = -1;
213 	}
214 out_put:
215 	addr_location__put(&al);
216 	return ret;
217 }
218 
219 static int hist_entry__tty_annotate(struct hist_entry *he,
220 				    struct perf_evsel *evsel,
221 				    struct perf_annotate *ann)
222 {
223 	return symbol__tty_annotate(he->ms.sym, he->ms.map, evsel,
224 				    ann->print_line, ann->full_paths, 0, 0);
225 }
226 
227 static void hists__find_annotations(struct hists *hists,
228 				    struct perf_evsel *evsel,
229 				    struct perf_annotate *ann)
230 {
231 	struct rb_node *nd = rb_first(&hists->entries), *next;
232 	int key = K_RIGHT;
233 
234 	while (nd) {
235 		struct hist_entry *he = rb_entry(nd, struct hist_entry, rb_node);
236 		struct annotation *notes;
237 
238 		if (he->ms.sym == NULL || he->ms.map->dso->annotate_warned)
239 			goto find_next;
240 
241 		notes = symbol__annotation(he->ms.sym);
242 		if (notes->src == NULL) {
243 find_next:
244 			if (key == K_LEFT)
245 				nd = rb_prev(nd);
246 			else
247 				nd = rb_next(nd);
248 			continue;
249 		}
250 
251 		if (use_browser == 2) {
252 			int ret;
253 			int (*annotate)(struct hist_entry *he,
254 					struct perf_evsel *evsel,
255 					struct hist_browser_timer *hbt);
256 
257 			annotate = dlsym(perf_gtk_handle,
258 					 "hist_entry__gtk_annotate");
259 			if (annotate == NULL) {
260 				ui__error("GTK browser not found!\n");
261 				return;
262 			}
263 
264 			ret = annotate(he, evsel, NULL);
265 			if (!ret || !ann->skip_missing)
266 				return;
267 
268 			/* skip missing symbols */
269 			nd = rb_next(nd);
270 		} else if (use_browser == 1) {
271 			key = hist_entry__tui_annotate(he, evsel, NULL);
272 			switch (key) {
273 			case -1:
274 				if (!ann->skip_missing)
275 					return;
276 				/* fall through */
277 			case K_RIGHT:
278 				next = rb_next(nd);
279 				break;
280 			case K_LEFT:
281 				next = rb_prev(nd);
282 				break;
283 			default:
284 				return;
285 			}
286 
287 			if (next != NULL)
288 				nd = next;
289 		} else {
290 			hist_entry__tty_annotate(he, evsel, ann);
291 			nd = rb_next(nd);
292 			/*
293 			 * Since we have a hist_entry per IP for the same
294 			 * symbol, free he->ms.sym->src to signal we already
295 			 * processed this symbol.
296 			 */
297 			zfree(&notes->src->cycles_hist);
298 			zfree(&notes->src);
299 		}
300 	}
301 }
302 
303 static int __cmd_annotate(struct perf_annotate *ann)
304 {
305 	int ret;
306 	struct perf_session *session = ann->session;
307 	struct perf_evsel *pos;
308 	u64 total_nr_samples;
309 
310 	if (ann->cpu_list) {
311 		ret = perf_session__cpu_bitmap(session, ann->cpu_list,
312 					       ann->cpu_bitmap);
313 		if (ret)
314 			goto out;
315 	}
316 
317 	if (!objdump_path) {
318 		ret = perf_env__lookup_objdump(&session->header.env);
319 		if (ret)
320 			goto out;
321 	}
322 
323 	ret = perf_session__process_events(session);
324 	if (ret)
325 		goto out;
326 
327 	if (dump_trace) {
328 		perf_session__fprintf_nr_events(session, stdout);
329 		perf_evlist__fprintf_nr_events(session->evlist, stdout);
330 		goto out;
331 	}
332 
333 	if (verbose > 3)
334 		perf_session__fprintf(session, stdout);
335 
336 	if (verbose > 2)
337 		perf_session__fprintf_dsos(session, stdout);
338 
339 	total_nr_samples = 0;
340 	evlist__for_each_entry(session->evlist, pos) {
341 		struct hists *hists = evsel__hists(pos);
342 		u32 nr_samples = hists->stats.nr_events[PERF_RECORD_SAMPLE];
343 
344 		if (nr_samples > 0) {
345 			total_nr_samples += nr_samples;
346 			hists__collapse_resort(hists, NULL);
347 			/* Don't sort callchain */
348 			perf_evsel__reset_sample_bit(pos, CALLCHAIN);
349 			perf_evsel__output_resort(pos, NULL);
350 
351 			if (symbol_conf.event_group &&
352 			    !perf_evsel__is_group_leader(pos))
353 				continue;
354 
355 			hists__find_annotations(hists, pos, ann);
356 		}
357 	}
358 
359 	if (total_nr_samples == 0) {
360 		ui__error("The %s file has no samples!\n", session->data->file.path);
361 		goto out;
362 	}
363 
364 	if (use_browser == 2) {
365 		void (*show_annotations)(void);
366 
367 		show_annotations = dlsym(perf_gtk_handle,
368 					 "perf_gtk__show_annotations");
369 		if (show_annotations == NULL) {
370 			ui__error("GTK browser not found!\n");
371 			goto out;
372 		}
373 		show_annotations();
374 	}
375 
376 out:
377 	return ret;
378 }
379 
380 static const char * const annotate_usage[] = {
381 	"perf annotate [<options>]",
382 	NULL
383 };
384 
385 int cmd_annotate(int argc, const char **argv)
386 {
387 	struct perf_annotate annotate = {
388 		.tool = {
389 			.sample	= process_sample_event,
390 			.mmap	= perf_event__process_mmap,
391 			.mmap2	= perf_event__process_mmap2,
392 			.comm	= perf_event__process_comm,
393 			.exit	= perf_event__process_exit,
394 			.fork	= perf_event__process_fork,
395 			.namespaces = perf_event__process_namespaces,
396 			.attr	= perf_event__process_attr,
397 			.build_id = perf_event__process_build_id,
398 			.tracing_data   = perf_event__process_tracing_data,
399 			.feature	= perf_event__process_feature,
400 			.ordered_events = true,
401 			.ordering_requires_timestamps = true,
402 		},
403 	};
404 	struct perf_data data = {
405 		.mode  = PERF_DATA_MODE_READ,
406 	};
407 	struct option options[] = {
408 	OPT_STRING('i', "input", &input_name, "file",
409 		    "input file name"),
410 	OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
411 		   "only consider symbols in these dsos"),
412 	OPT_STRING('s', "symbol", &annotate.sym_hist_filter, "symbol",
413 		    "symbol to annotate"),
414 	OPT_BOOLEAN('f', "force", &data.force, "don't complain, do it"),
415 	OPT_INCR('v', "verbose", &verbose,
416 		    "be more verbose (show symbol address, etc)"),
417 	OPT_BOOLEAN('q', "quiet", &quiet, "do now show any message"),
418 	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
419 		    "dump raw trace in ASCII"),
420 	OPT_BOOLEAN(0, "gtk", &annotate.use_gtk, "Use the GTK interface"),
421 	OPT_BOOLEAN(0, "tui", &annotate.use_tui, "Use the TUI interface"),
422 	OPT_BOOLEAN(0, "stdio", &annotate.use_stdio, "Use the stdio interface"),
423 	OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
424 		   "file", "vmlinux pathname"),
425 	OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
426 		    "load module symbols - WARNING: use only with -k and LIVE kernel"),
427 	OPT_BOOLEAN('l', "print-line", &annotate.print_line,
428 		    "print matching source lines (may be slow)"),
429 	OPT_BOOLEAN('P', "full-paths", &annotate.full_paths,
430 		    "Don't shorten the displayed pathnames"),
431 	OPT_BOOLEAN(0, "skip-missing", &annotate.skip_missing,
432 		    "Skip symbols that cannot be annotated"),
433 	OPT_STRING('C', "cpu", &annotate.cpu_list, "cpu", "list of cpus to profile"),
434 	OPT_CALLBACK(0, "symfs", NULL, "directory",
435 		     "Look for files with symbols relative to this directory",
436 		     symbol__config_symfs),
437 	OPT_BOOLEAN(0, "source", &symbol_conf.annotate_src,
438 		    "Interleave source code with assembly code (default)"),
439 	OPT_BOOLEAN(0, "asm-raw", &symbol_conf.annotate_asm_raw,
440 		    "Display raw encoding of assembly instructions (default)"),
441 	OPT_STRING('M', "disassembler-style", &disassembler_style, "disassembler style",
442 		   "Specify disassembler style (e.g. -M intel for intel syntax)"),
443 	OPT_STRING(0, "objdump", &objdump_path, "path",
444 		   "objdump binary to use for disassembly and annotations"),
445 	OPT_BOOLEAN(0, "group", &symbol_conf.event_group,
446 		    "Show event group information together"),
447 	OPT_BOOLEAN(0, "show-total-period", &symbol_conf.show_total_period,
448 		    "Show a column with the sum of periods"),
449 	OPT_BOOLEAN('n', "show-nr-samples", &symbol_conf.show_nr_samples,
450 		    "Show a column with the number of samples"),
451 	OPT_CALLBACK_DEFAULT(0, "stdio-color", NULL, "mode",
452 			     "'always' (default), 'never' or 'auto' only applicable to --stdio mode",
453 			     stdio__config_color, "always"),
454 	OPT_END()
455 	};
456 	int ret;
457 
458 	set_option_flag(options, 0, "show-total-period", PARSE_OPT_EXCLUSIVE);
459 	set_option_flag(options, 0, "show-nr-samples", PARSE_OPT_EXCLUSIVE);
460 
461 
462 	ret = hists__init();
463 	if (ret < 0)
464 		return ret;
465 
466 	argc = parse_options(argc, argv, options, annotate_usage, 0);
467 	if (argc) {
468 		/*
469 		 * Special case: if there's an argument left then assume that
470 		 * it's a symbol filter:
471 		 */
472 		if (argc > 1)
473 			usage_with_options(annotate_usage, options);
474 
475 		annotate.sym_hist_filter = argv[0];
476 	}
477 
478 	if (symbol_conf.show_nr_samples && annotate.use_gtk) {
479 		pr_err("--show-nr-samples is not available in --gtk mode at this time\n");
480 		return ret;
481 	}
482 
483 	if (quiet)
484 		perf_quiet_option();
485 
486 	data.file.path = input_name;
487 
488 	annotate.session = perf_session__new(&data, false, &annotate.tool);
489 	if (annotate.session == NULL)
490 		return -1;
491 
492 	ret = symbol__annotation_init();
493 	if (ret < 0)
494 		goto out_delete;
495 
496 	symbol_conf.try_vmlinux_path = true;
497 
498 	ret = symbol__init(&annotate.session->header.env);
499 	if (ret < 0)
500 		goto out_delete;
501 
502 	if (setup_sorting(NULL) < 0)
503 		usage_with_options(annotate_usage, options);
504 
505 	if (annotate.use_stdio)
506 		use_browser = 0;
507 	else if (annotate.use_tui)
508 		use_browser = 1;
509 	else if (annotate.use_gtk)
510 		use_browser = 2;
511 
512 	setup_browser(true);
513 
514 	ret = __cmd_annotate(&annotate);
515 
516 out_delete:
517 	/*
518 	 * Speed up the exit process, for large files this can
519 	 * take quite a while.
520 	 *
521 	 * XXX Enable this when using valgrind or if we ever
522 	 * librarize this command.
523 	 *
524 	 * Also experiment with obstacks to see how much speed
525 	 * up we'll get here.
526 	 *
527 	 * perf_session__delete(session);
528 	 */
529 	return ret;
530 }
531