tools/perf/builtin-diff.c

   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_displacement;
  27 static bool show_period;
  28 static bool show_formula;
  29 static bool show_baseline_only;
  30 static bool sort_compute;
  31
  32 static s64 compute_wdiff_w1;
  33 static s64 compute_wdiff_w2;
  34
  35 enum {
  36         COMPUTE_DELTA,
  37         COMPUTE_RATIO,
  38         COMPUTE_WEIGHTED_DIFF,
  39         COMPUTE_MAX,
  40 };
  41
  42 const char *compute_names[COMPUTE_MAX] = {
  43         [COMPUTE_DELTA] = "delta",
  44         [COMPUTE_RATIO] = "ratio",
  45         [COMPUTE_WEIGHTED_DIFF] = "wdiff",
  46 };
  47
  48 static int compute;
  49
  50 static int setup_compute_opt_wdiff(char *opt)
  51 {
  52         char *w1_str = opt;
  53         char *w2_str;
  54
  55         int ret = -EINVAL;
  56
  57         if (!opt)
  58                 goto out;
  59
  60         w2_str = strchr(opt, ',');
  61         if (!w2_str)
  62                 goto out;
  63
  64         *w2_str++ = 0x0;
  65         if (!*w2_str)
  66                 goto out;
  67
  68         compute_wdiff_w1 = strtol(w1_str, NULL, 10);
  69         compute_wdiff_w2 = strtol(w2_str, NULL, 10);
  70
  71         if (!compute_wdiff_w1 || !compute_wdiff_w2)
  72                 goto out;
  73
  74         pr_debug("compute wdiff w1(%" PRId64 ") w2(%" PRId64 ")\n",
  75                   compute_wdiff_w1, compute_wdiff_w2);
  76
  77         ret = 0;
  78
  79  out:
  80         if (ret)
  81                 pr_err("Failed: wrong weight data, use 'wdiff:w1,w2'\n");
  82
  83         return ret;
  84 }
  85
  86 static int setup_compute_opt(char *opt)
  87 {
  88         if (compute == COMPUTE_WEIGHTED_DIFF)
  89                 return setup_compute_opt_wdiff(opt);
  90
  91         if (opt) {
  92                 pr_err("Failed: extra option specified '%s'", opt);
  93                 return -EINVAL;
  94         }
  95
  96         return 0;
  97 }
  98
  99 static int setup_compute(const struct option *opt, const char *str,
 100                          int unset __maybe_unused)
 101 {
 102         int *cp = (int *) opt->value;
 103         char *cstr = (char *) str;
 104         char buf[50];
 105         unsigned i;
 106         char *option;
 107
 108         if (!str) {
 109                 *cp = COMPUTE_DELTA;
 110                 return 0;
 111         }
 112
 113         if (*str == '+') {
 114                 sort_compute = true;
 115                 cstr = (char *) ++str;
 116                 if (!*str)
 117                         return 0;
 118         }
 119
 120         option = strchr(str, ':');
 121         if (option) {
 122                 unsigned len = option++ - str;
 123
 124                 /*
 125                  * The str data are not writeable, so we need
 126                  * to use another buffer.
 127                  */
 128
 129                 /* No option value is longer. */
 130                 if (len >= sizeof(buf))
 131                         return -EINVAL;
 132
 133                 strncpy(buf, str, len);
 134                 buf[len] = 0x0;
 135                 cstr = buf;
 136         }
 137
 138         for (i = 0; i < COMPUTE_MAX; i++)
 139                 if (!strcmp(cstr, compute_names[i])) {
 140                         *cp = i;
 141                         return setup_compute_opt(option);
 142                 }
 143
 144         pr_err("Failed: '%s' is not computation method "
 145                "(use 'delta','ratio' or 'wdiff')\n", str);
 146         return -EINVAL;
 147 }
 148
 149 static double get_period_percent(struct hist_entry *he, u64 period)
 150 {
 151         u64 total = he->hists->stats.total_period;
 152         return (period * 100.0) / total;
 153 }
 154
 155 double perf_diff__compute_delta(struct hist_entry *he)
 156 {
 157         struct hist_entry *pair = he->pair;
 158         double new_percent = get_period_percent(he, he->stat.period);
 159         double old_percent = pair ? get_period_percent(pair, pair->stat.period) : 0.0;
 160
 161         he->diff.period_ratio_delta = new_percent - old_percent;
 162         he->diff.computed = true;
 163         return he->diff.period_ratio_delta;
 164 }
 165
 166 double perf_diff__compute_ratio(struct hist_entry *he)
 167 {
 168         struct hist_entry *pair = he->pair;
 169         double new_period = he->stat.period;
 170         double old_period = pair ? pair->stat.period : 0;
 171
 172         he->diff.computed = true;
 173         he->diff.period_ratio = pair ? (new_period / old_period) : 0;
 174         return he->diff.period_ratio;
 175 }
 176
 177 s64 perf_diff__compute_wdiff(struct hist_entry *he)
 178 {
 179         struct hist_entry *pair = he->pair;
 180         u64 new_period = he->stat.period;
 181         u64 old_period = pair ? pair->stat.period : 0;
 182
 183         he->diff.computed = true;
 184
 185         if (!pair)
 186                 he->diff.wdiff = 0;
 187         else
 188                 he->diff.wdiff = new_period * compute_wdiff_w2 -
 189                                  old_period * compute_wdiff_w1;
 190
 191         return he->diff.wdiff;
 192 }
 193
 194 static int formula_delta(struct hist_entry *he, char *buf, size_t size)
 195 {
 196         struct hist_entry *pair = he->pair;
 197
 198         if (!pair)
 199                 return -1;
 200
 201         return scnprintf(buf, size,
 202                          "(%" PRIu64 " * 100 / %" PRIu64 ") - "
 203                          "(%" PRIu64 " * 100 / %" PRIu64 ")",
 204                           he->stat.period, he->hists->stats.total_period,
 205                           pair->stat.period, pair->hists->stats.total_period);
 206 }
 207
 208 static int formula_ratio(struct hist_entry *he, char *buf, size_t size)
 209 {
 210         struct hist_entry *pair = he->pair;
 211         double new_period = he->stat.period;
 212         double old_period = pair ? pair->stat.period : 0;
 213
 214         if (!pair)
 215                 return -1;
 216
 217         return scnprintf(buf, size, "%.0F / %.0F", new_period, old_period);
 218 }
 219
 220 static int formula_wdiff(struct hist_entry *he, char *buf, size_t size)
 221 {
 222         struct hist_entry *pair = he->pair;
 223         u64 new_period = he->stat.period;
 224         u64 old_period = pair ? pair->stat.period : 0;
 225
 226         if (!pair)
 227                 return -1;
 228
 229         return scnprintf(buf, size,
 230                   "(%" PRIu64 " * " "%" PRId64 ") - (%" PRIu64 " * " "%" PRId64 ")",
 231                   new_period, compute_wdiff_w2, old_period, compute_wdiff_w1);
 232 }
 233
 234 int perf_diff__formula(char *buf, size_t size, struct hist_entry *he)
 235 {
 236         switch (compute) {
 237         case COMPUTE_DELTA:
 238                 return formula_delta(he, buf, size);
 239         case COMPUTE_RATIO:
 240                 return formula_ratio(he, buf, size);
 241         case COMPUTE_WEIGHTED_DIFF:
 242                 return formula_wdiff(he, buf, size);
 243         default:
 244                 BUG_ON(1);
 245         }
 246
 247         return -1;
 248 }
 249
 250 static int hists__add_entry(struct hists *self,
 251                             struct addr_location *al, u64 period)
 252 {
 253         if (__hists__add_entry(self, al, NULL, period) != NULL)
 254                 return 0;
 255         return -ENOMEM;
 256 }
 257
 258 static int diff__process_sample_event(struct perf_tool *tool __maybe_unused,
 259                                       union perf_event *event,
 260                                       struct perf_sample *sample,
 261                                       struct perf_evsel *evsel,
 262                                       struct machine *machine)
 263 {
 264         struct addr_location al;
 265
 266         if (perf_event__preprocess_sample(event, machine, &al, sample, NULL) < 0) {
 267                 pr_warning("problem processing %d event, skipping it.\n",
 268                            event->header.type);
 269                 return -1;
 270         }
 271
 272         if (al.filtered)
 273                 return 0;
 274
 275         if (hists__add_entry(&evsel->hists, &al, sample->period)) {
 276                 pr_warning("problem incrementing symbol period, skipping event\n");
 277                 return -1;
 278         }
 279
 280         evsel->hists.stats.total_period += sample->period;
 281         return 0;
 282 }
 283
 284 static struct perf_tool tool = {
 285         .sample = diff__process_sample_event,
 286         .mmap   = perf_event__process_mmap,
 287         .comm   = perf_event__process_comm,
 288         .exit   = perf_event__process_exit,
 289         .fork   = perf_event__process_fork,
 290         .lost   = perf_event__process_lost,
 291         .ordered_samples = true,
 292         .ordering_requires_timestamps = true,
 293 };
 294
 295 static void insert_hist_entry_by_name(struct rb_root *root,
 296                                       struct hist_entry *he)
 297 {
 298         struct rb_node **p = &root->rb_node;
 299         struct rb_node *parent = NULL;
 300         struct hist_entry *iter;
 301
 302         while (*p != NULL) {
 303                 parent = *p;
 304                 iter = rb_entry(parent, struct hist_entry, rb_node);
 305                 if (hist_entry__cmp(he, iter) < 0)
 306                         p = &(*p)->rb_left;
 307                 else
 308                         p = &(*p)->rb_right;
 309         }
 310
 311         rb_link_node(&he->rb_node, parent, p);
 312         rb_insert_color(&he->rb_node, root);
 313 }
 314
 315 static void hists__name_resort(struct hists *self, bool sort)
 316 {
 317         unsigned long position = 1;
 318         struct rb_root tmp = RB_ROOT;
 319         struct rb_node *next = rb_first(&self->entries);
 320
 321         while (next != NULL) {
 322                 struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node);
 323
 324                 next = rb_next(&n->rb_node);
 325                 n->position = position++;
 326
 327                 if (sort) {
 328                         rb_erase(&n->rb_node, &self->entries);
 329                         insert_hist_entry_by_name(&tmp, n);
 330                 }
 331         }
 332
 333         if (sort)
 334                 self->entries = tmp;
 335 }
 336
 337 static struct hist_entry *hists__find_entry(struct hists *self,
 338                                             struct hist_entry *he)
 339 {
 340         struct rb_node *n = self->entries.rb_node;
 341
 342         while (n) {
 343                 struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node);
 344                 int64_t cmp = hist_entry__cmp(he, iter);
 345
 346                 if (cmp < 0)
 347                         n = n->rb_left;
 348                 else if (cmp > 0)
 349                         n = n->rb_right;
 350                 else
 351                         return iter;
 352         }
 353
 354         return NULL;
 355 }
 356
 357 static void hists__match(struct hists *older, struct hists *newer)
 358 {
 359         struct rb_node *nd;
 360
 361         for (nd = rb_first(&newer->entries); nd; nd = rb_next(nd)) {
 362                 struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node);
 363                 pos->pair = hists__find_entry(older, pos);
 364         }
 365 }
 366
 367 static struct perf_evsel *evsel_match(struct perf_evsel *evsel,
 368                                       struct perf_evlist *evlist)
 369 {
 370         struct perf_evsel *e;
 371
 372         list_for_each_entry(e, &evlist->entries, node)
 373                 if (perf_evsel__match2(evsel, e))
 374                         return e;
 375
 376         return NULL;
 377 }
 378
 379 static void perf_evlist__resort_hists(struct perf_evlist *evlist, bool name)
 380 {
 381         struct perf_evsel *evsel;
 382
 383         list_for_each_entry(evsel, &evlist->entries, node) {
 384                 struct hists *hists = &evsel->hists;
 385
 386                 hists__output_resort(hists);
 387
 388                 /*
 389                  * The hists__name_resort only sets possition
 390                  * if name is false.
 391                  */
 392                 if (name || ((!name) && show_displacement))
 393                         hists__name_resort(hists, name);
 394         }
 395 }
 396
 397 static void hists__baseline_only(struct hists *hists)
 398 {
 399         struct rb_node *next = rb_first(&hists->entries);
 400
 401         while (next != NULL) {
 402                 struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node);
 403
 404                 next = rb_next(&he->rb_node);
 405                 if (!he->pair) {
 406                         rb_erase(&he->rb_node, &hists->entries);
 407                         hist_entry__free(he);
 408                 }
 409         }
 410 }
 411
 412 static void hists__precompute(struct hists *hists)
 413 {
 414         struct rb_node *next = rb_first(&hists->entries);
 415
 416         while (next != NULL) {
 417                 struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node);
 418
 419                 next = rb_next(&he->rb_node);
 420
 421                 switch (compute) {
 422                 case COMPUTE_DELTA:
 423                         perf_diff__compute_delta(he);
 424                         break;
 425                 case COMPUTE_RATIO:
 426                         perf_diff__compute_ratio(he);
 427                         break;
 428                 case COMPUTE_WEIGHTED_DIFF:
 429                         perf_diff__compute_wdiff(he);
 430                         break;
 431                 default:
 432                         BUG_ON(1);
 433                 }
 434         }
 435 }
 436
 437 static int64_t cmp_doubles(double l, double r)
 438 {
 439         if (l > r)
 440                 return -1;
 441         else if (l < r)
 442                 return 1;
 443         else
 444                 return 0;
 445 }
 446
 447 static int64_t
 448 hist_entry__cmp_compute(struct hist_entry *left, struct hist_entry *right,
 449                         int c)
 450 {
 451         switch (c) {
 452         case COMPUTE_DELTA:
 453         {
 454                 double l = left->diff.period_ratio_delta;
 455                 double r = right->diff.period_ratio_delta;
 456
 457                 return cmp_doubles(l, r);
 458         }
 459         case COMPUTE_RATIO:
 460         {
 461                 double l = left->diff.period_ratio;
 462                 double r = right->diff.period_ratio;
 463
 464                 return cmp_doubles(l, r);
 465         }
 466         case COMPUTE_WEIGHTED_DIFF:
 467         {
 468                 s64 l = left->diff.wdiff;
 469                 s64 r = right->diff.wdiff;
 470
 471                 return r - l;
 472         }
 473         default:
 474                 BUG_ON(1);
 475         }
 476
 477         return 0;
 478 }
 479
 480 static void insert_hist_entry_by_compute(struct rb_root *root,
 481                                          struct hist_entry *he,
 482                                          int c)
 483 {
 484         struct rb_node **p = &root->rb_node;
 485         struct rb_node *parent = NULL;
 486         struct hist_entry *iter;
 487
 488         while (*p != NULL) {
 489                 parent = *p;
 490                 iter = rb_entry(parent, struct hist_entry, rb_node);
 491                 if (hist_entry__cmp_compute(he, iter, c) < 0)
 492                         p = &(*p)->rb_left;
 493                 else
 494                         p = &(*p)->rb_right;
 495         }
 496
 497         rb_link_node(&he->rb_node, parent, p);
 498         rb_insert_color(&he->rb_node, root);
 499 }
 500
 501 static void hists__compute_resort(struct hists *hists)
 502 {
 503         struct rb_root tmp = RB_ROOT;
 504         struct rb_node *next = rb_first(&hists->entries);
 505
 506         while (next != NULL) {
 507                 struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node);
 508
 509                 next = rb_next(&he->rb_node);
 510
 511                 rb_erase(&he->rb_node, &hists->entries);
 512                 insert_hist_entry_by_compute(&tmp, he, compute);
 513         }
 514
 515         hists->entries = tmp;
 516 }
 517
 518 static void hists__process(struct hists *old, struct hists *new)
 519 {
 520         hists__match(old, new);
 521
 522         if (show_baseline_only)
 523                 hists__baseline_only(new);
 524
 525         if (sort_compute) {
 526                 hists__precompute(new);
 527                 hists__compute_resort(new);
 528         }
 529
 530         hists__fprintf(new, true, 0, 0, stdout);
 531 }
 532
 533 static int __cmd_diff(void)
 534 {
 535         int ret, i;
 536 #define older (session[0])
 537 #define newer (session[1])
 538         struct perf_session *session[2];
 539         struct perf_evlist *evlist_new, *evlist_old;
 540         struct perf_evsel *evsel;
 541         bool first = true;
 542
 543         older = perf_session__new(input_old, O_RDONLY, force, false,
 544                                   &tool);
 545         newer = perf_session__new(input_new, O_RDONLY, force, false,
 546                                   &tool);
 547         if (session[0] == NULL || session[1] == NULL)
 548                 return -ENOMEM;
 549
 550         for (i = 0; i < 2; ++i) {
 551                 ret = perf_session__process_events(session[i], &tool);
 552                 if (ret)
 553                         goto out_delete;
 554         }
 555
 556         evlist_old = older->evlist;
 557         evlist_new = newer->evlist;
 558
 559         perf_evlist__resort_hists(evlist_old, true);
 560         perf_evlist__resort_hists(evlist_new, false);
 561
 562         list_for_each_entry(evsel, &evlist_new->entries, node) {
 563                 struct perf_evsel *evsel_old;
 564
 565                 evsel_old = evsel_match(evsel, evlist_old);
 566                 if (!evsel_old)
 567                         continue;
 568
 569                 fprintf(stdout, "%s# Event '%s'\n#\n", first ? "" : "\n",
 570                         perf_evsel__name(evsel));
 571
 572                 first = false;
 573
 574                 hists__process(&evsel_old->hists, &evsel->hists);
 575         }
 576
 577 out_delete:
 578         for (i = 0; i < 2; ++i)
 579                 perf_session__delete(session[i]);
 580         return ret;
 581 #undef older
 582 #undef newer
 583 }
 584
 585 static const char * const diff_usage[] = {
 586         "perf diff [<options>] [old_file] [new_file]",
 587         NULL,
 588 };
 589
 590 static const struct option options[] = {
 591         OPT_INCR('v', "verbose", &verbose,
 592                     "be more verbose (show symbol address, etc)"),
 593         OPT_BOOLEAN('M', "displacement", &show_displacement,
 594                     "Show position displacement relative to baseline"),
 595         OPT_BOOLEAN('b', "baseline-only", &show_baseline_only,
 596                     "Show only items with match in baseline"),
 597         OPT_CALLBACK('c', "compute", &compute,
 598                      "delta,ratio,wdiff:w1,w2 (default delta)",
 599                      "Entries differential computation selection",
 600                      setup_compute),
 601         OPT_BOOLEAN('p', "period", &show_period,
 602                     "Show period values."),
 603         OPT_BOOLEAN('F', "formula", &show_formula,
 604                     "Show formula."),
 605         OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 606                     "dump raw trace in ASCII"),
 607         OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
 608         OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
 609                     "load module symbols - WARNING: use only with -k and LIVE kernel"),
 610         OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
 611                    "only consider symbols in these dsos"),
 612         OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
 613                    "only consider symbols in these comms"),
 614         OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
 615                    "only consider these symbols"),
 616         OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
 617                    "sort by key(s): pid, comm, dso, symbol, parent"),
 618         OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
 619                    "separator for columns, no spaces will be added between "
 620                    "columns '.' is reserved."),
 621         OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
 622                     "Look for files with symbols relative to this directory"),
 623         OPT_END()
 624 };
 625
 626 static void ui_init(void)
 627 {
 628         perf_hpp__init();
 629
 630         /* No overhead column. */
 631         perf_hpp__column_enable(PERF_HPP__OVERHEAD, false);
 632
 633         /*
 634          * Display baseline/delta/ratio/displacement/
 635          * formula/periods columns.
 636          */
 637         perf_hpp__column_enable(PERF_HPP__BASELINE, true);
 638
 639         switch (compute) {
 640         case COMPUTE_DELTA:
 641                 perf_hpp__column_enable(PERF_HPP__DELTA, true);
 642                 break;
 643         case COMPUTE_RATIO:
 644                 perf_hpp__column_enable(PERF_HPP__RATIO, true);
 645                 break;
 646         case COMPUTE_WEIGHTED_DIFF:
 647                 perf_hpp__column_enable(PERF_HPP__WEIGHTED_DIFF, true);
 648                 break;
 649         default:
 650                 BUG_ON(1);
 651         };
 652
 653         if (show_displacement)
 654                 perf_hpp__column_enable(PERF_HPP__DISPL, true);
 655
 656         if (show_formula)
 657                 perf_hpp__column_enable(PERF_HPP__FORMULA, true);
 658
 659         if (show_period) {
 660                 perf_hpp__column_enable(PERF_HPP__PERIOD, true);
 661                 perf_hpp__column_enable(PERF_HPP__PERIOD_BASELINE, true);
 662         }
 663 }
 664
 665 int cmd_diff(int argc, const char **argv, const char *prefix __maybe_unused)
 666 {
 667         sort_order = diff__default_sort_order;
 668         argc = parse_options(argc, argv, options, diff_usage, 0);
 669         if (argc) {
 670                 if (argc > 2)
 671                         usage_with_options(diff_usage, options);
 672                 if (argc == 2) {
 673                         input_old = argv[0];
 674                         input_new = argv[1];
 675                 } else
 676                         input_new = argv[0];
 677         } else if (symbol_conf.default_guest_vmlinux_name ||
 678                    symbol_conf.default_guest_kallsyms) {
 679                 input_old = "perf.data.host";
 680                 input_new = "perf.data.guest";
 681         }
 682
 683         symbol_conf.exclude_other = false;
 684         if (symbol__init() < 0)
 685                 return -1;
 686
 687         ui_init();
 688
 689         setup_sorting(diff_usage, options);
 690         setup_pager();
 691
 692         sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
 693         sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
 694         sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
 695
 696         return __cmd_diff();
 697 }