xref: /openbmc/linux/tools/perf/builtin-annotate.c (revision d28bcd53)
1 /*
2  * builtin-annotate.c
3  *
4  * Builtin annotate command: Analyze the perf.data input file,
5  * look up and read DSOs and symbol information and display
6  * a histogram of results, along various sorting keys.
7  */
8 #include "builtin.h"
9 
10 #include "util/util.h"
11 #include "util/color.h"
12 #include <linux/list.h>
13 #include "util/cache.h"
14 #include <linux/rbtree.h>
15 #include "util/symbol.h"
16 
17 #include "perf.h"
18 #include "util/debug.h"
19 
20 #include "util/evlist.h"
21 #include "util/evsel.h"
22 #include "util/annotate.h"
23 #include "util/event.h"
24 #include <subcmd/parse-options.h>
25 #include "util/parse-events.h"
26 #include "util/thread.h"
27 #include "util/sort.h"
28 #include "util/hist.h"
29 #include "util/session.h"
30 #include "util/tool.h"
31 #include "util/data.h"
32 #include "arch/common.h"
33 #include "util/block-range.h"
34 
35 #include <dlfcn.h>
36 #include <errno.h>
37 #include <linux/bitmap.h>
38 
39 struct perf_annotate {
40 	struct perf_tool tool;
41 	struct perf_session *session;
42 	bool	   use_tui, use_stdio, use_gtk;
43 	bool	   full_paths;
44 	bool	   print_line;
45 	bool	   skip_missing;
46 	const char *sym_hist_filter;
47 	const char *cpu_list;
48 	DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
49 };
50 
51 /*
52  * Given one basic block:
53  *
54  *	from	to		branch_i
55  *	* ----> *
56  *		|
57  *		| block
58  *		v
59  *		* ----> *
60  *		from	to	branch_i+1
61  *
62  * where the horizontal are the branches and the vertical is the executed
63  * block of instructions.
64  *
65  * We count, for each 'instruction', the number of blocks that covered it as
66  * well as count the ratio each branch is taken.
67  *
68  * We can do this without knowing the actual instruction stream by keeping
69  * track of the address ranges. We break down ranges such that there is no
70  * overlap and iterate from the start until the end.
71  *
72  * @acme: once we parse the objdump output _before_ processing the samples,
73  * we can easily fold the branch.cycles IPC bits in.
74  */
75 static void process_basic_block(struct addr_map_symbol *start,
76 				struct addr_map_symbol *end,
77 				struct branch_flags *flags)
78 {
79 	struct symbol *sym = start->sym;
80 	struct annotation *notes = sym ? symbol__annotation(sym) : NULL;
81 	struct block_range_iter iter;
82 	struct block_range *entry;
83 
84 	/*
85 	 * Sanity; NULL isn't executable and the CPU cannot execute backwards
86 	 */
87 	if (!start->addr || start->addr > end->addr)
88 		return;
89 
90 	iter = block_range__create(start->addr, end->addr);
91 	if (!block_range_iter__valid(&iter))
92 		return;
93 
94 	/*
95 	 * First block in range is a branch target.
96 	 */
97 	entry = block_range_iter(&iter);
98 	assert(entry->is_target);
99 	entry->entry++;
100 
101 	do {
102 		entry = block_range_iter(&iter);
103 
104 		entry->coverage++;
105 		entry->sym = sym;
106 
107 		if (notes)
108 			notes->max_coverage = max(notes->max_coverage, entry->coverage);
109 
110 	} while (block_range_iter__next(&iter));
111 
112 	/*
113 	 * Last block in rage is a branch.
114 	 */
115 	entry = block_range_iter(&iter);
116 	assert(entry->is_branch);
117 	entry->taken++;
118 	if (flags->predicted)
119 		entry->pred++;
120 }
121 
122 static void process_branch_stack(struct branch_stack *bs, struct addr_location *al,
123 				 struct perf_sample *sample)
124 {
125 	struct addr_map_symbol *prev = NULL;
126 	struct branch_info *bi;
127 	int i;
128 
129 	if (!bs || !bs->nr)
130 		return;
131 
132 	bi = sample__resolve_bstack(sample, al);
133 	if (!bi)
134 		return;
135 
136 	for (i = bs->nr - 1; i >= 0; i--) {
137 		/*
138 		 * XXX filter against symbol
139 		 */
140 		if (prev)
141 			process_basic_block(prev, &bi[i].from, &bi[i].flags);
142 		prev = &bi[i].to;
143 	}
144 
145 	free(bi);
146 }
147 
148 static int perf_evsel__add_sample(struct perf_evsel *evsel,
149 				  struct perf_sample *sample,
150 				  struct addr_location *al,
151 				  struct perf_annotate *ann)
152 {
153 	struct hists *hists = evsel__hists(evsel);
154 	struct hist_entry *he;
155 	int ret;
156 
157 	if (ann->sym_hist_filter != NULL &&
158 	    (al->sym == NULL ||
159 	     strcmp(ann->sym_hist_filter, al->sym->name) != 0)) {
160 		/* We're only interested in a symbol named sym_hist_filter */
161 		/*
162 		 * FIXME: why isn't this done in the symbol_filter when loading
163 		 * the DSO?
164 		 */
165 		if (al->sym != NULL) {
166 			rb_erase(&al->sym->rb_node,
167 				 &al->map->dso->symbols[al->map->type]);
168 			symbol__delete(al->sym);
169 			dso__reset_find_symbol_cache(al->map->dso);
170 		}
171 		return 0;
172 	}
173 
174 	/*
175 	 * XXX filtered samples can still have branch entires pointing into our
176 	 * symbol and are missed.
177 	 */
178 	process_branch_stack(sample->branch_stack, al, sample);
179 
180 	sample->period = 1;
181 	sample->weight = 1;
182 
183 	he = hists__add_entry(hists, al, NULL, NULL, NULL, sample, true);
184 	if (he == NULL)
185 		return -ENOMEM;
186 
187 	ret = hist_entry__inc_addr_samples(he, evsel->idx, al->addr);
188 	hists__inc_nr_samples(hists, true);
189 	return ret;
190 }
191 
192 static int process_sample_event(struct perf_tool *tool,
193 				union perf_event *event,
194 				struct perf_sample *sample,
195 				struct perf_evsel *evsel,
196 				struct machine *machine)
197 {
198 	struct perf_annotate *ann = container_of(tool, struct perf_annotate, tool);
199 	struct addr_location al;
200 	int ret = 0;
201 
202 	if (machine__resolve(machine, &al, sample) < 0) {
203 		pr_warning("problem processing %d event, skipping it.\n",
204 			   event->header.type);
205 		return -1;
206 	}
207 
208 	if (ann->cpu_list && !test_bit(sample->cpu, ann->cpu_bitmap))
209 		goto out_put;
210 
211 	if (!al.filtered && perf_evsel__add_sample(evsel, sample, &al, ann)) {
212 		pr_warning("problem incrementing symbol count, "
213 			   "skipping event\n");
214 		ret = -1;
215 	}
216 out_put:
217 	addr_location__put(&al);
218 	return ret;
219 }
220 
221 static int hist_entry__tty_annotate(struct hist_entry *he,
222 				    struct perf_evsel *evsel,
223 				    struct perf_annotate *ann)
224 {
225 	return symbol__tty_annotate(he->ms.sym, he->ms.map, evsel,
226 				    ann->print_line, ann->full_paths, 0, 0);
227 }
228 
229 static void hists__find_annotations(struct hists *hists,
230 				    struct perf_evsel *evsel,
231 				    struct perf_annotate *ann)
232 {
233 	struct rb_node *nd = rb_first(&hists->entries), *next;
234 	int key = K_RIGHT;
235 
236 	while (nd) {
237 		struct hist_entry *he = rb_entry(nd, struct hist_entry, rb_node);
238 		struct annotation *notes;
239 
240 		if (he->ms.sym == NULL || he->ms.map->dso->annotate_warned)
241 			goto find_next;
242 
243 		notes = symbol__annotation(he->ms.sym);
244 		if (notes->src == NULL) {
245 find_next:
246 			if (key == K_LEFT)
247 				nd = rb_prev(nd);
248 			else
249 				nd = rb_next(nd);
250 			continue;
251 		}
252 
253 		if (use_browser == 2) {
254 			int ret;
255 			int (*annotate)(struct hist_entry *he,
256 					struct perf_evsel *evsel,
257 					struct hist_browser_timer *hbt);
258 
259 			annotate = dlsym(perf_gtk_handle,
260 					 "hist_entry__gtk_annotate");
261 			if (annotate == NULL) {
262 				ui__error("GTK browser not found!\n");
263 				return;
264 			}
265 
266 			ret = annotate(he, evsel, NULL);
267 			if (!ret || !ann->skip_missing)
268 				return;
269 
270 			/* skip missing symbols */
271 			nd = rb_next(nd);
272 		} else if (use_browser == 1) {
273 			key = hist_entry__tui_annotate(he, evsel, NULL);
274 			switch (key) {
275 			case -1:
276 				if (!ann->skip_missing)
277 					return;
278 				/* fall through */
279 			case K_RIGHT:
280 				next = rb_next(nd);
281 				break;
282 			case K_LEFT:
283 				next = rb_prev(nd);
284 				break;
285 			default:
286 				return;
287 			}
288 
289 			if (next != NULL)
290 				nd = next;
291 		} else {
292 			hist_entry__tty_annotate(he, evsel, ann);
293 			nd = rb_next(nd);
294 			/*
295 			 * Since we have a hist_entry per IP for the same
296 			 * symbol, free he->ms.sym->src to signal we already
297 			 * processed this symbol.
298 			 */
299 			zfree(&notes->src->cycles_hist);
300 			zfree(&notes->src);
301 		}
302 	}
303 }
304 
305 static int __cmd_annotate(struct perf_annotate *ann)
306 {
307 	int ret;
308 	struct perf_session *session = ann->session;
309 	struct perf_evsel *pos;
310 	u64 total_nr_samples;
311 
312 	if (ann->cpu_list) {
313 		ret = perf_session__cpu_bitmap(session, ann->cpu_list,
314 					       ann->cpu_bitmap);
315 		if (ret)
316 			goto out;
317 	}
318 
319 	if (!objdump_path) {
320 		ret = perf_env__lookup_objdump(&session->header.env);
321 		if (ret)
322 			goto out;
323 	}
324 
325 	ret = perf_session__process_events(session);
326 	if (ret)
327 		goto out;
328 
329 	if (dump_trace) {
330 		perf_session__fprintf_nr_events(session, stdout);
331 		perf_evlist__fprintf_nr_events(session->evlist, stdout);
332 		goto out;
333 	}
334 
335 	if (verbose > 3)
336 		perf_session__fprintf(session, stdout);
337 
338 	if (verbose > 2)
339 		perf_session__fprintf_dsos(session, stdout);
340 
341 	total_nr_samples = 0;
342 	evlist__for_each_entry(session->evlist, pos) {
343 		struct hists *hists = evsel__hists(pos);
344 		u32 nr_samples = hists->stats.nr_events[PERF_RECORD_SAMPLE];
345 
346 		if (nr_samples > 0) {
347 			total_nr_samples += nr_samples;
348 			hists__collapse_resort(hists, NULL);
349 			/* Don't sort callchain */
350 			perf_evsel__reset_sample_bit(pos, CALLCHAIN);
351 			perf_evsel__output_resort(pos, NULL);
352 
353 			if (symbol_conf.event_group &&
354 			    !perf_evsel__is_group_leader(pos))
355 				continue;
356 
357 			hists__find_annotations(hists, pos, ann);
358 		}
359 	}
360 
361 	if (total_nr_samples == 0) {
362 		ui__error("The %s file has no samples!\n", session->file->path);
363 		goto out;
364 	}
365 
366 	if (use_browser == 2) {
367 		void (*show_annotations)(void);
368 
369 		show_annotations = dlsym(perf_gtk_handle,
370 					 "perf_gtk__show_annotations");
371 		if (show_annotations == NULL) {
372 			ui__error("GTK browser not found!\n");
373 			goto out;
374 		}
375 		show_annotations();
376 	}
377 
378 out:
379 	return ret;
380 }
381 
382 static const char * const annotate_usage[] = {
383 	"perf annotate [<options>]",
384 	NULL
385 };
386 
387 int cmd_annotate(int argc, const char **argv)
388 {
389 	struct perf_annotate annotate = {
390 		.tool = {
391 			.sample	= process_sample_event,
392 			.mmap	= perf_event__process_mmap,
393 			.mmap2	= perf_event__process_mmap2,
394 			.comm	= perf_event__process_comm,
395 			.exit	= perf_event__process_exit,
396 			.fork	= perf_event__process_fork,
397 			.namespaces = perf_event__process_namespaces,
398 			.attr	= perf_event__process_attr,
399 			.build_id = perf_event__process_build_id,
400 			.ordered_events = true,
401 			.ordering_requires_timestamps = true,
402 		},
403 	};
404 	struct perf_data_file file = {
405 		.mode  = PERF_DATA_MODE_READ,
406 	};
407 	const 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", &file.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_CALLBACK_DEFAULT(0, "stdio-color", NULL, "mode",
450 			     "'always' (default), 'never' or 'auto' only applicable to --stdio mode",
451 			     stdio__config_color, "always"),
452 	OPT_END()
453 	};
454 	int ret = hists__init();
455 
456 	if (ret < 0)
457 		return ret;
458 
459 	argc = parse_options(argc, argv, options, annotate_usage, 0);
460 	if (argc) {
461 		/*
462 		 * Special case: if there's an argument left then assume that
463 		 * it's a symbol filter:
464 		 */
465 		if (argc > 1)
466 			usage_with_options(annotate_usage, options);
467 
468 		annotate.sym_hist_filter = argv[0];
469 	}
470 
471 	if (quiet)
472 		perf_quiet_option();
473 
474 	file.path  = input_name;
475 
476 	annotate.session = perf_session__new(&file, false, &annotate.tool);
477 	if (annotate.session == NULL)
478 		return -1;
479 
480 	ret = symbol__annotation_init();
481 	if (ret < 0)
482 		goto out_delete;
483 
484 	symbol_conf.try_vmlinux_path = true;
485 
486 	ret = symbol__init(&annotate.session->header.env);
487 	if (ret < 0)
488 		goto out_delete;
489 
490 	if (setup_sorting(NULL) < 0)
491 		usage_with_options(annotate_usage, options);
492 
493 	if (annotate.use_stdio)
494 		use_browser = 0;
495 	else if (annotate.use_tui)
496 		use_browser = 1;
497 	else if (annotate.use_gtk)
498 		use_browser = 2;
499 
500 	setup_browser(true);
501 
502 	ret = __cmd_annotate(&annotate);
503 
504 out_delete:
505 	/*
506 	 * Speed up the exit process, for large files this can
507 	 * take quite a while.
508 	 *
509 	 * XXX Enable this when using valgrind or if we ever
510 	 * librarize this command.
511 	 *
512 	 * Also experiment with obstacks to see how much speed
513 	 * up we'll get here.
514 	 *
515 	 * perf_session__delete(session);
516 	 */
517 	return ret;
518 }
519