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 = hist_entry__next_pair(he);
 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 = hist_entry__next_pair(he);
 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 = hist_entry__next_pair(he);
 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 = hist_entry__next_pair(he);
 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 = hist_entry__next_pair(he);
 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 = hist_entry__next_pair(he);
 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 perf_evsel *evsel_match(struct perf_evsel *evsel,
 338                                       struct perf_evlist *evlist)
 339 {
 340         struct perf_evsel *e;
 341
 342         list_for_each_entry(e, &evlist->entries, node)
 343                 if (perf_evsel__match2(evsel, e))
 344                         return e;
 345
 346         return NULL;
 347 }
 348
 349 static void perf_evlist__resort_hists(struct perf_evlist *evlist, bool name)
 350 {
 351         struct perf_evsel *evsel;
 352
 353         list_for_each_entry(evsel, &evlist->entries, node) {
 354                 struct hists *hists = &evsel->hists;
 355
 356                 hists__output_resort(hists);
 357
 358                 /*
 359                  * The hists__name_resort only sets possition
 360                  * if name is false.
 361                  */
 362                 if (name || ((!name) && show_displacement))
 363                         hists__name_resort(hists, name);
 364         }
 365 }
 366
 367 static void hists__baseline_only(struct hists *hists)
 368 {
 369         struct rb_node *next = rb_first(&hists->entries);
 370
 371         while (next != NULL) {
 372                 struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node);
 373
 374                 next = rb_next(&he->rb_node);
 375                 if (!hist_entry__next_pair(he)) {
 376                         rb_erase(&he->rb_node, &hists->entries);
 377                         hist_entry__free(he);
 378                 }
 379         }
 380 }
 381
 382 static void hists__precompute(struct hists *hists)
 383 {
 384         struct rb_node *next = rb_first(&hists->entries);
 385
 386         while (next != NULL) {
 387                 struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node);
 388
 389                 next = rb_next(&he->rb_node);
 390
 391                 switch (compute) {
 392                 case COMPUTE_DELTA:
 393                         perf_diff__compute_delta(he);
 394                         break;
 395                 case COMPUTE_RATIO:
 396                         perf_diff__compute_ratio(he);
 397                         break;
 398                 case COMPUTE_WEIGHTED_DIFF:
 399                         perf_diff__compute_wdiff(he);
 400                         break;
 401                 default:
 402                         BUG_ON(1);
 403                 }
 404         }
 405 }
 406
 407 static int64_t cmp_doubles(double l, double r)
 408 {
 409         if (l > r)
 410                 return -1;
 411         else if (l < r)
 412                 return 1;
 413         else
 414                 return 0;
 415 }
 416
 417 static int64_t
 418 hist_entry__cmp_compute(struct hist_entry *left, struct hist_entry *right,
 419                         int c)
 420 {
 421         switch (c) {
 422         case COMPUTE_DELTA:
 423         {
 424                 double l = left->diff.period_ratio_delta;
 425                 double r = right->diff.period_ratio_delta;
 426
 427                 return cmp_doubles(l, r);
 428         }
 429         case COMPUTE_RATIO:
 430         {
 431                 double l = left->diff.period_ratio;
 432                 double r = right->diff.period_ratio;
 433
 434                 return cmp_doubles(l, r);
 435         }
 436         case COMPUTE_WEIGHTED_DIFF:
 437         {
 438                 s64 l = left->diff.wdiff;
 439                 s64 r = right->diff.wdiff;
 440
 441                 return r - l;
 442         }
 443         default:
 444                 BUG_ON(1);
 445         }
 446
 447         return 0;
 448 }
 449
 450 static void insert_hist_entry_by_compute(struct rb_root *root,
 451                                          struct hist_entry *he,
 452                                          int c)
 453 {
 454         struct rb_node **p = &root->rb_node;
 455         struct rb_node *parent = NULL;
 456         struct hist_entry *iter;
 457
 458         while (*p != NULL) {
 459                 parent = *p;
 460                 iter = rb_entry(parent, struct hist_entry, rb_node);
 461                 if (hist_entry__cmp_compute(he, iter, c) < 0)
 462                         p = &(*p)->rb_left;
 463                 else
 464                         p = &(*p)->rb_right;
 465         }
 466
 467         rb_link_node(&he->rb_node, parent, p);
 468         rb_insert_color(&he->rb_node, root);
 469 }
 470
 471 static void hists__compute_resort(struct hists *hists)
 472 {
 473         struct rb_root tmp = RB_ROOT;
 474         struct rb_node *next = rb_first(&hists->entries);
 475
 476         while (next != NULL) {
 477                 struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node);
 478
 479                 next = rb_next(&he->rb_node);
 480
 481                 rb_erase(&he->rb_node, &hists->entries);
 482                 insert_hist_entry_by_compute(&tmp, he, compute);
 483         }
 484
 485         hists->entries = tmp;
 486 }
 487
 488 static void hists__process(struct hists *old, struct hists *new)
 489 {
 490         hists__match(new, old);
 491
 492         if (show_baseline_only)
 493                 hists__baseline_only(new);
 494         else
 495                 hists__link(new, old);
 496
 497         if (sort_compute) {
 498                 hists__precompute(new);
 499                 hists__compute_resort(new);
 500         }
 501
 502         hists__fprintf(new, true, 0, 0, stdout);
 503 }
 504
 505 static int __cmd_diff(void)
 506 {
 507         int ret, i;
 508 #define older (session[0])
 509 #define newer (session[1])
 510         struct perf_session *session[2];
 511         struct perf_evlist *evlist_new, *evlist_old;
 512         struct perf_evsel *evsel;
 513         bool first = true;
 514
 515         older = perf_session__new(input_old, O_RDONLY, force, false,
 516                                   &tool);
 517         newer = perf_session__new(input_new, O_RDONLY, force, false,
 518                                   &tool);
 519         if (session[0] == NULL || session[1] == NULL)
 520                 return -ENOMEM;
 521
 522         for (i = 0; i < 2; ++i) {
 523                 ret = perf_session__process_events(session[i], &tool);
 524                 if (ret)
 525                         goto out_delete;
 526         }
 527
 528         evlist_old = older->evlist;
 529         evlist_new = newer->evlist;
 530
 531         perf_evlist__resort_hists(evlist_old, true);
 532         perf_evlist__resort_hists(evlist_new, false);
 533
 534         list_for_each_entry(evsel, &evlist_new->entries, node) {
 535                 struct perf_evsel *evsel_old;
 536
 537                 evsel_old = evsel_match(evsel, evlist_old);
 538                 if (!evsel_old)
 539                         continue;
 540
 541                 fprintf(stdout, "%s# Event '%s'\n#\n", first ? "" : "\n",
 542                         perf_evsel__name(evsel));
 543
 544                 first = false;
 545
 546                 hists__process(&evsel_old->hists, &evsel->hists);
 547         }
 548
 549 out_delete:
 550         for (i = 0; i < 2; ++i)
 551                 perf_session__delete(session[i]);
 552         return ret;
 553 #undef older
 554 #undef newer
 555 }
 556
 557 static const char * const diff_usage[] = {
 558         "perf diff [<options>] [old_file] [new_file]",
 559         NULL,
 560 };
 561
 562 static const struct option options[] = {
 563         OPT_INCR('v', "verbose", &verbose,
 564                     "be more verbose (show symbol address, etc)"),
 565         OPT_BOOLEAN('M', "displacement", &show_displacement,
 566                     "Show position displacement relative to baseline"),
 567         OPT_BOOLEAN('b', "baseline-only", &show_baseline_only,
 568                     "Show only items with match in baseline"),
 569         OPT_CALLBACK('c', "compute", &compute,
 570                      "delta,ratio,wdiff:w1,w2 (default delta)",
 571                      "Entries differential computation selection",
 572                      setup_compute),
 573         OPT_BOOLEAN('p', "period", &show_period,
 574                     "Show period values."),
 575         OPT_BOOLEAN('F', "formula", &show_formula,
 576                     "Show formula."),
 577         OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 578                     "dump raw trace in ASCII"),
 579         OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
 580         OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
 581                     "load module symbols - WARNING: use only with -k and LIVE kernel"),
 582         OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
 583                    "only consider symbols in these dsos"),
 584         OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
 585                    "only consider symbols in these comms"),
 586         OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
 587                    "only consider these symbols"),
 588         OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
 589                    "sort by key(s): pid, comm, dso, symbol, parent"),
 590         OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
 591                    "separator for columns, no spaces will be added between "
 592                    "columns '.' is reserved."),
 593         OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
 594                     "Look for files with symbols relative to this directory"),
 595         OPT_END()
 596 };
 597
 598 static void ui_init(void)
 599 {
 600         perf_hpp__init();
 601
 602         /* No overhead column. */
 603         perf_hpp__column_enable(PERF_HPP__OVERHEAD, false);
 604
 605         /*
 606          * Display baseline/delta/ratio/displacement/
 607          * formula/periods columns.
 608          */
 609         perf_hpp__column_enable(PERF_HPP__BASELINE, true);
 610
 611         switch (compute) {
 612         case COMPUTE_DELTA:
 613                 perf_hpp__column_enable(PERF_HPP__DELTA, true);
 614                 break;
 615         case COMPUTE_RATIO:
 616                 perf_hpp__column_enable(PERF_HPP__RATIO, true);
 617                 break;
 618         case COMPUTE_WEIGHTED_DIFF:
 619                 perf_hpp__column_enable(PERF_HPP__WEIGHTED_DIFF, true);
 620                 break;
 621         default:
 622                 BUG_ON(1);
 623         };
 624
 625         if (show_displacement)
 626                 perf_hpp__column_enable(PERF_HPP__DISPL, true);
 627
 628         if (show_formula)
 629                 perf_hpp__column_enable(PERF_HPP__FORMULA, true);
 630
 631         if (show_period) {
 632                 perf_hpp__column_enable(PERF_HPP__PERIOD, true);
 633                 perf_hpp__column_enable(PERF_HPP__PERIOD_BASELINE, true);
 634         }
 635 }
 636
 637 int cmd_diff(int argc, const char **argv, const char *prefix __maybe_unused)
 638 {
 639         sort_order = diff__default_sort_order;
 640         argc = parse_options(argc, argv, options, diff_usage, 0);
 641         if (argc) {
 642                 if (argc > 2)
 643                         usage_with_options(diff_usage, options);
 644                 if (argc == 2) {
 645                         input_old = argv[0];
 646                         input_new = argv[1];
 647                 } else
 648                         input_new = argv[0];
 649         } else if (symbol_conf.default_guest_vmlinux_name ||
 650                    symbol_conf.default_guest_kallsyms) {
 651                 input_old = "perf.data.host";
 652                 input_new = "perf.data.guest";
 653         }
 654
 655         symbol_conf.exclude_other = false;
 656         if (symbol__init() < 0)
 657                 return -1;
 658
 659         ui_init();
 660
 661         setup_sorting(diff_usage, options);
 662         setup_pager();
 663
 664         sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
 665         sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
 666         sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
 667
 668         return __cmd_diff();
 669 }