xref: /openbmc/linux/tools/perf/builtin-diff.c (revision 9d749629)
1 /*
2  * builtin-diff.c
3  *
4  * Builtin diff command: Analyze two perf.data input files, look up and read
5  * DSOs and symbol information, sort them and produce a diff.
6  */
7 #include "builtin.h"
8 
9 #include "util/debug.h"
10 #include "util/event.h"
11 #include "util/hist.h"
12 #include "util/evsel.h"
13 #include "util/evlist.h"
14 #include "util/session.h"
15 #include "util/tool.h"
16 #include "util/sort.h"
17 #include "util/symbol.h"
18 #include "util/util.h"
19 
20 #include <stdlib.h>
21 
22 static char const *input_old = "perf.data.old",
23 		  *input_new = "perf.data";
24 static char	  diff__default_sort_order[] = "dso,symbol";
25 static bool  force;
26 static bool show_period;
27 static bool show_formula;
28 static bool show_baseline_only;
29 static bool sort_compute;
30 
31 static s64 compute_wdiff_w1;
32 static s64 compute_wdiff_w2;
33 
34 enum {
35 	COMPUTE_DELTA,
36 	COMPUTE_RATIO,
37 	COMPUTE_WEIGHTED_DIFF,
38 	COMPUTE_MAX,
39 };
40 
41 const char *compute_names[COMPUTE_MAX] = {
42 	[COMPUTE_DELTA] = "delta",
43 	[COMPUTE_RATIO] = "ratio",
44 	[COMPUTE_WEIGHTED_DIFF] = "wdiff",
45 };
46 
47 static int compute;
48 
49 static int setup_compute_opt_wdiff(char *opt)
50 {
51 	char *w1_str = opt;
52 	char *w2_str;
53 
54 	int ret = -EINVAL;
55 
56 	if (!opt)
57 		goto out;
58 
59 	w2_str = strchr(opt, ',');
60 	if (!w2_str)
61 		goto out;
62 
63 	*w2_str++ = 0x0;
64 	if (!*w2_str)
65 		goto out;
66 
67 	compute_wdiff_w1 = strtol(w1_str, NULL, 10);
68 	compute_wdiff_w2 = strtol(w2_str, NULL, 10);
69 
70 	if (!compute_wdiff_w1 || !compute_wdiff_w2)
71 		goto out;
72 
73 	pr_debug("compute wdiff w1(%" PRId64 ") w2(%" PRId64 ")\n",
74 		  compute_wdiff_w1, compute_wdiff_w2);
75 
76 	ret = 0;
77 
78  out:
79 	if (ret)
80 		pr_err("Failed: wrong weight data, use 'wdiff:w1,w2'\n");
81 
82 	return ret;
83 }
84 
85 static int setup_compute_opt(char *opt)
86 {
87 	if (compute == COMPUTE_WEIGHTED_DIFF)
88 		return setup_compute_opt_wdiff(opt);
89 
90 	if (opt) {
91 		pr_err("Failed: extra option specified '%s'", opt);
92 		return -EINVAL;
93 	}
94 
95 	return 0;
96 }
97 
98 static int setup_compute(const struct option *opt, const char *str,
99 			 int unset __maybe_unused)
100 {
101 	int *cp = (int *) opt->value;
102 	char *cstr = (char *) str;
103 	char buf[50];
104 	unsigned i;
105 	char *option;
106 
107 	if (!str) {
108 		*cp = COMPUTE_DELTA;
109 		return 0;
110 	}
111 
112 	if (*str == '+') {
113 		sort_compute = true;
114 		cstr = (char *) ++str;
115 		if (!*str)
116 			return 0;
117 	}
118 
119 	option = strchr(str, ':');
120 	if (option) {
121 		unsigned len = option++ - str;
122 
123 		/*
124 		 * The str data are not writeable, so we need
125 		 * to use another buffer.
126 		 */
127 
128 		/* No option value is longer. */
129 		if (len >= sizeof(buf))
130 			return -EINVAL;
131 
132 		strncpy(buf, str, len);
133 		buf[len] = 0x0;
134 		cstr = buf;
135 	}
136 
137 	for (i = 0; i < COMPUTE_MAX; i++)
138 		if (!strcmp(cstr, compute_names[i])) {
139 			*cp = i;
140 			return setup_compute_opt(option);
141 		}
142 
143 	pr_err("Failed: '%s' is not computation method "
144 	       "(use 'delta','ratio' or 'wdiff')\n", str);
145 	return -EINVAL;
146 }
147 
148 double perf_diff__period_percent(struct hist_entry *he, u64 period)
149 {
150 	u64 total = he->hists->stats.total_period;
151 	return (period * 100.0) / total;
152 }
153 
154 double perf_diff__compute_delta(struct hist_entry *he, struct hist_entry *pair)
155 {
156 	double new_percent = perf_diff__period_percent(he, he->stat.period);
157 	double old_percent = perf_diff__period_percent(pair, pair->stat.period);
158 
159 	he->diff.period_ratio_delta = new_percent - old_percent;
160 	he->diff.computed = true;
161 	return he->diff.period_ratio_delta;
162 }
163 
164 double perf_diff__compute_ratio(struct hist_entry *he, struct hist_entry *pair)
165 {
166 	double new_period = he->stat.period;
167 	double old_period = pair->stat.period;
168 
169 	he->diff.computed = true;
170 	he->diff.period_ratio = new_period / old_period;
171 	return he->diff.period_ratio;
172 }
173 
174 s64 perf_diff__compute_wdiff(struct hist_entry *he, struct hist_entry *pair)
175 {
176 	u64 new_period = he->stat.period;
177 	u64 old_period = pair->stat.period;
178 
179 	he->diff.computed = true;
180 	he->diff.wdiff = new_period * compute_wdiff_w2 -
181 			 old_period * compute_wdiff_w1;
182 
183 	return he->diff.wdiff;
184 }
185 
186 static int formula_delta(struct hist_entry *he, struct hist_entry *pair,
187 			 char *buf, size_t size)
188 {
189 	return scnprintf(buf, size,
190 			 "(%" PRIu64 " * 100 / %" PRIu64 ") - "
191 			 "(%" PRIu64 " * 100 / %" PRIu64 ")",
192 			  he->stat.period, he->hists->stats.total_period,
193 			  pair->stat.period, pair->hists->stats.total_period);
194 }
195 
196 static int formula_ratio(struct hist_entry *he, struct hist_entry *pair,
197 			 char *buf, size_t size)
198 {
199 	double new_period = he->stat.period;
200 	double old_period = pair->stat.period;
201 
202 	return scnprintf(buf, size, "%.0F / %.0F", new_period, old_period);
203 }
204 
205 static int formula_wdiff(struct hist_entry *he, struct hist_entry *pair,
206 			 char *buf, size_t size)
207 {
208 	u64 new_period = he->stat.period;
209 	u64 old_period = pair->stat.period;
210 
211 	return scnprintf(buf, size,
212 		  "(%" PRIu64 " * " "%" PRId64 ") - (%" PRIu64 " * " "%" PRId64 ")",
213 		  new_period, compute_wdiff_w2, old_period, compute_wdiff_w1);
214 }
215 
216 int perf_diff__formula(struct hist_entry *he, struct hist_entry *pair,
217 		       char *buf, size_t size)
218 {
219 	switch (compute) {
220 	case COMPUTE_DELTA:
221 		return formula_delta(he, pair, buf, size);
222 	case COMPUTE_RATIO:
223 		return formula_ratio(he, pair, buf, size);
224 	case COMPUTE_WEIGHTED_DIFF:
225 		return formula_wdiff(he, pair, buf, size);
226 	default:
227 		BUG_ON(1);
228 	}
229 
230 	return -1;
231 }
232 
233 static int hists__add_entry(struct hists *self,
234 			    struct addr_location *al, u64 period)
235 {
236 	if (__hists__add_entry(self, al, NULL, period) != NULL)
237 		return 0;
238 	return -ENOMEM;
239 }
240 
241 static int diff__process_sample_event(struct perf_tool *tool __maybe_unused,
242 				      union perf_event *event,
243 				      struct perf_sample *sample,
244 				      struct perf_evsel *evsel,
245 				      struct machine *machine)
246 {
247 	struct addr_location al;
248 
249 	if (perf_event__preprocess_sample(event, machine, &al, sample, NULL) < 0) {
250 		pr_warning("problem processing %d event, skipping it.\n",
251 			   event->header.type);
252 		return -1;
253 	}
254 
255 	if (al.filtered)
256 		return 0;
257 
258 	if (hists__add_entry(&evsel->hists, &al, sample->period)) {
259 		pr_warning("problem incrementing symbol period, skipping event\n");
260 		return -1;
261 	}
262 
263 	evsel->hists.stats.total_period += sample->period;
264 	return 0;
265 }
266 
267 static struct perf_tool tool = {
268 	.sample	= diff__process_sample_event,
269 	.mmap	= perf_event__process_mmap,
270 	.comm	= perf_event__process_comm,
271 	.exit	= perf_event__process_exit,
272 	.fork	= perf_event__process_fork,
273 	.lost	= perf_event__process_lost,
274 	.ordered_samples = true,
275 	.ordering_requires_timestamps = true,
276 };
277 
278 static struct perf_evsel *evsel_match(struct perf_evsel *evsel,
279 				      struct perf_evlist *evlist)
280 {
281 	struct perf_evsel *e;
282 
283 	list_for_each_entry(e, &evlist->entries, node)
284 		if (perf_evsel__match2(evsel, e))
285 			return e;
286 
287 	return NULL;
288 }
289 
290 static void perf_evlist__collapse_resort(struct perf_evlist *evlist)
291 {
292 	struct perf_evsel *evsel;
293 
294 	list_for_each_entry(evsel, &evlist->entries, node) {
295 		struct hists *hists = &evsel->hists;
296 
297 		hists__collapse_resort(hists);
298 	}
299 }
300 
301 static void hists__baseline_only(struct hists *hists)
302 {
303 	struct rb_root *root;
304 	struct rb_node *next;
305 
306 	if (sort__need_collapse)
307 		root = &hists->entries_collapsed;
308 	else
309 		root = hists->entries_in;
310 
311 	next = rb_first(root);
312 	while (next != NULL) {
313 		struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node_in);
314 
315 		next = rb_next(&he->rb_node_in);
316 		if (!hist_entry__next_pair(he)) {
317 			rb_erase(&he->rb_node_in, root);
318 			hist_entry__free(he);
319 		}
320 	}
321 }
322 
323 static void hists__precompute(struct hists *hists)
324 {
325 	struct rb_node *next = rb_first(&hists->entries);
326 
327 	while (next != NULL) {
328 		struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node);
329 		struct hist_entry *pair = hist_entry__next_pair(he);
330 
331 		next = rb_next(&he->rb_node);
332 		if (!pair)
333 			continue;
334 
335 		switch (compute) {
336 		case COMPUTE_DELTA:
337 			perf_diff__compute_delta(he, pair);
338 			break;
339 		case COMPUTE_RATIO:
340 			perf_diff__compute_ratio(he, pair);
341 			break;
342 		case COMPUTE_WEIGHTED_DIFF:
343 			perf_diff__compute_wdiff(he, pair);
344 			break;
345 		default:
346 			BUG_ON(1);
347 		}
348 	}
349 }
350 
351 static int64_t cmp_doubles(double l, double r)
352 {
353 	if (l > r)
354 		return -1;
355 	else if (l < r)
356 		return 1;
357 	else
358 		return 0;
359 }
360 
361 static int64_t
362 hist_entry__cmp_compute(struct hist_entry *left, struct hist_entry *right,
363 			int c)
364 {
365 	switch (c) {
366 	case COMPUTE_DELTA:
367 	{
368 		double l = left->diff.period_ratio_delta;
369 		double r = right->diff.period_ratio_delta;
370 
371 		return cmp_doubles(l, r);
372 	}
373 	case COMPUTE_RATIO:
374 	{
375 		double l = left->diff.period_ratio;
376 		double r = right->diff.period_ratio;
377 
378 		return cmp_doubles(l, r);
379 	}
380 	case COMPUTE_WEIGHTED_DIFF:
381 	{
382 		s64 l = left->diff.wdiff;
383 		s64 r = right->diff.wdiff;
384 
385 		return r - l;
386 	}
387 	default:
388 		BUG_ON(1);
389 	}
390 
391 	return 0;
392 }
393 
394 static void insert_hist_entry_by_compute(struct rb_root *root,
395 					 struct hist_entry *he,
396 					 int c)
397 {
398 	struct rb_node **p = &root->rb_node;
399 	struct rb_node *parent = NULL;
400 	struct hist_entry *iter;
401 
402 	while (*p != NULL) {
403 		parent = *p;
404 		iter = rb_entry(parent, struct hist_entry, rb_node);
405 		if (hist_entry__cmp_compute(he, iter, c) < 0)
406 			p = &(*p)->rb_left;
407 		else
408 			p = &(*p)->rb_right;
409 	}
410 
411 	rb_link_node(&he->rb_node, parent, p);
412 	rb_insert_color(&he->rb_node, root);
413 }
414 
415 static void hists__compute_resort(struct hists *hists)
416 {
417 	struct rb_root *root;
418 	struct rb_node *next;
419 
420 	if (sort__need_collapse)
421 		root = &hists->entries_collapsed;
422 	else
423 		root = hists->entries_in;
424 
425 	hists->entries = RB_ROOT;
426 	next = rb_first(root);
427 
428 	hists->nr_entries = 0;
429 	hists->stats.total_period = 0;
430 	hists__reset_col_len(hists);
431 
432 	while (next != NULL) {
433 		struct hist_entry *he;
434 
435 		he = rb_entry(next, struct hist_entry, rb_node_in);
436 		next = rb_next(&he->rb_node_in);
437 
438 		insert_hist_entry_by_compute(&hists->entries, he, compute);
439 		hists__inc_nr_entries(hists, he);
440 	}
441 }
442 
443 static void hists__process(struct hists *old, struct hists *new)
444 {
445 	hists__match(new, old);
446 
447 	if (show_baseline_only)
448 		hists__baseline_only(new);
449 	else
450 		hists__link(new, old);
451 
452 	if (sort_compute) {
453 		hists__precompute(new);
454 		hists__compute_resort(new);
455 	} else {
456 		hists__output_resort(new);
457 	}
458 
459 	hists__fprintf(new, true, 0, 0, stdout);
460 }
461 
462 static int __cmd_diff(void)
463 {
464 	int ret, i;
465 #define older (session[0])
466 #define newer (session[1])
467 	struct perf_session *session[2];
468 	struct perf_evlist *evlist_new, *evlist_old;
469 	struct perf_evsel *evsel;
470 	bool first = true;
471 
472 	older = perf_session__new(input_old, O_RDONLY, force, false,
473 				  &tool);
474 	newer = perf_session__new(input_new, O_RDONLY, force, false,
475 				  &tool);
476 	if (session[0] == NULL || session[1] == NULL)
477 		return -ENOMEM;
478 
479 	for (i = 0; i < 2; ++i) {
480 		ret = perf_session__process_events(session[i], &tool);
481 		if (ret)
482 			goto out_delete;
483 	}
484 
485 	evlist_old = older->evlist;
486 	evlist_new = newer->evlist;
487 
488 	perf_evlist__collapse_resort(evlist_old);
489 	perf_evlist__collapse_resort(evlist_new);
490 
491 	list_for_each_entry(evsel, &evlist_new->entries, node) {
492 		struct perf_evsel *evsel_old;
493 
494 		evsel_old = evsel_match(evsel, evlist_old);
495 		if (!evsel_old)
496 			continue;
497 
498 		fprintf(stdout, "%s# Event '%s'\n#\n", first ? "" : "\n",
499 			perf_evsel__name(evsel));
500 
501 		first = false;
502 
503 		hists__process(&evsel_old->hists, &evsel->hists);
504 	}
505 
506 out_delete:
507 	for (i = 0; i < 2; ++i)
508 		perf_session__delete(session[i]);
509 	return ret;
510 #undef older
511 #undef newer
512 }
513 
514 static const char * const diff_usage[] = {
515 	"perf diff [<options>] [old_file] [new_file]",
516 	NULL,
517 };
518 
519 static const struct option options[] = {
520 	OPT_INCR('v', "verbose", &verbose,
521 		    "be more verbose (show symbol address, etc)"),
522 	OPT_BOOLEAN('b', "baseline-only", &show_baseline_only,
523 		    "Show only items with match in baseline"),
524 	OPT_CALLBACK('c', "compute", &compute,
525 		     "delta,ratio,wdiff:w1,w2 (default delta)",
526 		     "Entries differential computation selection",
527 		     setup_compute),
528 	OPT_BOOLEAN('p', "period", &show_period,
529 		    "Show period values."),
530 	OPT_BOOLEAN('F', "formula", &show_formula,
531 		    "Show formula."),
532 	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
533 		    "dump raw trace in ASCII"),
534 	OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
535 	OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
536 		    "load module symbols - WARNING: use only with -k and LIVE kernel"),
537 	OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
538 		   "only consider symbols in these dsos"),
539 	OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
540 		   "only consider symbols in these comms"),
541 	OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
542 		   "only consider these symbols"),
543 	OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
544 		   "sort by key(s): pid, comm, dso, symbol, parent"),
545 	OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
546 		   "separator for columns, no spaces will be added between "
547 		   "columns '.' is reserved."),
548 	OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
549 		    "Look for files with symbols relative to this directory"),
550 	OPT_END()
551 };
552 
553 static void ui_init(void)
554 {
555 	/*
556 	 * Display baseline/delta/ratio
557 	 * formula/periods columns.
558 	 */
559 	perf_hpp__column_enable(PERF_HPP__BASELINE);
560 
561 	switch (compute) {
562 	case COMPUTE_DELTA:
563 		perf_hpp__column_enable(PERF_HPP__DELTA);
564 		break;
565 	case COMPUTE_RATIO:
566 		perf_hpp__column_enable(PERF_HPP__RATIO);
567 		break;
568 	case COMPUTE_WEIGHTED_DIFF:
569 		perf_hpp__column_enable(PERF_HPP__WEIGHTED_DIFF);
570 		break;
571 	default:
572 		BUG_ON(1);
573 	};
574 
575 	if (show_formula)
576 		perf_hpp__column_enable(PERF_HPP__FORMULA);
577 
578 	if (show_period) {
579 		perf_hpp__column_enable(PERF_HPP__PERIOD);
580 		perf_hpp__column_enable(PERF_HPP__PERIOD_BASELINE);
581 	}
582 }
583 
584 int cmd_diff(int argc, const char **argv, const char *prefix __maybe_unused)
585 {
586 	sort_order = diff__default_sort_order;
587 	argc = parse_options(argc, argv, options, diff_usage, 0);
588 	if (argc) {
589 		if (argc > 2)
590 			usage_with_options(diff_usage, options);
591 		if (argc == 2) {
592 			input_old = argv[0];
593 			input_new = argv[1];
594 		} else
595 			input_new = argv[0];
596 	} else if (symbol_conf.default_guest_vmlinux_name ||
597 		   symbol_conf.default_guest_kallsyms) {
598 		input_old = "perf.data.host";
599 		input_new = "perf.data.guest";
600 	}
601 
602 	symbol_conf.exclude_other = false;
603 	if (symbol__init() < 0)
604 		return -1;
605 
606 	ui_init();
607 
608 	if (setup_sorting() < 0)
609 		usage_with_options(diff_usage, options);
610 
611 	setup_pager();
612 
613 	sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
614 	sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
615 	sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
616 
617 	return __cmd_diff();
618 }
619