linux/tools/perf/builtin-diff.c
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   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
  22static char const *input_old = "perf.data.old",
  23                  *input_new = "perf.data";
  24static char       diff__default_sort_order[] = "dso,symbol";
  25static bool  force;
  26static bool show_period;
  27static bool show_formula;
  28static bool show_baseline_only;
  29static bool sort_compute;
  30
  31static s64 compute_wdiff_w1;
  32static s64 compute_wdiff_w2;
  33
  34enum {
  35        COMPUTE_DELTA,
  36        COMPUTE_RATIO,
  37        COMPUTE_WEIGHTED_DIFF,
  38        COMPUTE_MAX,
  39};
  40
  41const char *compute_names[COMPUTE_MAX] = {
  42        [COMPUTE_DELTA] = "delta",
  43        [COMPUTE_RATIO] = "ratio",
  44        [COMPUTE_WEIGHTED_DIFF] = "wdiff",
  45};
  46
  47static int compute;
  48
  49static 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
  85static 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
  98static 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
 148double 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
 154double 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
 164double 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
 174s64 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
 186static 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
 196static 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
 205static 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
 216int 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
 233static int hists__add_entry(struct hists *self,
 234                            struct addr_location *al, u64 period,
 235                            u64 weight)
 236{
 237        if (__hists__add_entry(self, al, NULL, period, weight) != NULL)
 238                return 0;
 239        return -ENOMEM;
 240}
 241
 242static int diff__process_sample_event(struct perf_tool *tool __maybe_unused,
 243                                      union perf_event *event,
 244                                      struct perf_sample *sample,
 245                                      struct perf_evsel *evsel,
 246                                      struct machine *machine)
 247{
 248        struct addr_location al;
 249
 250        if (perf_event__preprocess_sample(event, machine, &al, sample, NULL) < 0) {
 251                pr_warning("problem processing %d event, skipping it.\n",
 252                           event->header.type);
 253                return -1;
 254        }
 255
 256        if (al.filtered)
 257                return 0;
 258
 259        if (hists__add_entry(&evsel->hists, &al, sample->period, sample->weight)) {
 260                pr_warning("problem incrementing symbol period, skipping event\n");
 261                return -1;
 262        }
 263
 264        evsel->hists.stats.total_period += sample->period;
 265        return 0;
 266}
 267
 268static struct perf_tool tool = {
 269        .sample = diff__process_sample_event,
 270        .mmap   = perf_event__process_mmap,
 271        .comm   = perf_event__process_comm,
 272        .exit   = perf_event__process_exit,
 273        .fork   = perf_event__process_fork,
 274        .lost   = perf_event__process_lost,
 275        .ordered_samples = true,
 276        .ordering_requires_timestamps = true,
 277};
 278
 279static struct perf_evsel *evsel_match(struct perf_evsel *evsel,
 280                                      struct perf_evlist *evlist)
 281{
 282        struct perf_evsel *e;
 283
 284        list_for_each_entry(e, &evlist->entries, node)
 285                if (perf_evsel__match2(evsel, e))
 286                        return e;
 287
 288        return NULL;
 289}
 290
 291static void perf_evlist__collapse_resort(struct perf_evlist *evlist)
 292{
 293        struct perf_evsel *evsel;
 294
 295        list_for_each_entry(evsel, &evlist->entries, node) {
 296                struct hists *hists = &evsel->hists;
 297
 298                hists__collapse_resort(hists);
 299        }
 300}
 301
 302static void hists__baseline_only(struct hists *hists)
 303{
 304        struct rb_root *root;
 305        struct rb_node *next;
 306
 307        if (sort__need_collapse)
 308                root = &hists->entries_collapsed;
 309        else
 310                root = hists->entries_in;
 311
 312        next = rb_first(root);
 313        while (next != NULL) {
 314                struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node_in);
 315
 316                next = rb_next(&he->rb_node_in);
 317                if (!hist_entry__next_pair(he)) {
 318                        rb_erase(&he->rb_node_in, root);
 319                        hist_entry__free(he);
 320                }
 321        }
 322}
 323
 324static void hists__precompute(struct hists *hists)
 325{
 326        struct rb_root *root;
 327        struct rb_node *next;
 328
 329        if (sort__need_collapse)
 330                root = &hists->entries_collapsed;
 331        else
 332                root = hists->entries_in;
 333
 334        next = rb_first(root);
 335        while (next != NULL) {
 336                struct hist_entry *he = rb_entry(next, struct hist_entry, rb_node_in);
 337                struct hist_entry *pair = hist_entry__next_pair(he);
 338
 339                next = rb_next(&he->rb_node_in);
 340                if (!pair)
 341                        continue;
 342
 343                switch (compute) {
 344                case COMPUTE_DELTA:
 345                        perf_diff__compute_delta(he, pair);
 346                        break;
 347                case COMPUTE_RATIO:
 348                        perf_diff__compute_ratio(he, pair);
 349                        break;
 350                case COMPUTE_WEIGHTED_DIFF:
 351                        perf_diff__compute_wdiff(he, pair);
 352                        break;
 353                default:
 354                        BUG_ON(1);
 355                }
 356        }
 357}
 358
 359static int64_t cmp_doubles(double l, double r)
 360{
 361        if (l > r)
 362                return -1;
 363        else if (l < r)
 364                return 1;
 365        else
 366                return 0;
 367}
 368
 369static int64_t
 370hist_entry__cmp_compute(struct hist_entry *left, struct hist_entry *right,
 371                        int c)
 372{
 373        switch (c) {
 374        case COMPUTE_DELTA:
 375        {
 376                double l = left->diff.period_ratio_delta;
 377                double r = right->diff.period_ratio_delta;
 378
 379                return cmp_doubles(l, r);
 380        }
 381        case COMPUTE_RATIO:
 382        {
 383                double l = left->diff.period_ratio;
 384                double r = right->diff.period_ratio;
 385
 386                return cmp_doubles(l, r);
 387        }
 388        case COMPUTE_WEIGHTED_DIFF:
 389        {
 390                s64 l = left->diff.wdiff;
 391                s64 r = right->diff.wdiff;
 392
 393                return r - l;
 394        }
 395        default:
 396                BUG_ON(1);
 397        }
 398
 399        return 0;
 400}
 401
 402static void insert_hist_entry_by_compute(struct rb_root *root,
 403                                         struct hist_entry *he,
 404                                         int c)
 405{
 406        struct rb_node **p = &root->rb_node;
 407        struct rb_node *parent = NULL;
 408        struct hist_entry *iter;
 409
 410        while (*p != NULL) {
 411                parent = *p;
 412                iter = rb_entry(parent, struct hist_entry, rb_node);
 413                if (hist_entry__cmp_compute(he, iter, c) < 0)
 414                        p = &(*p)->rb_left;
 415                else
 416                        p = &(*p)->rb_right;
 417        }
 418
 419        rb_link_node(&he->rb_node, parent, p);
 420        rb_insert_color(&he->rb_node, root);
 421}
 422
 423static void hists__compute_resort(struct hists *hists)
 424{
 425        struct rb_root *root;
 426        struct rb_node *next;
 427
 428        if (sort__need_collapse)
 429                root = &hists->entries_collapsed;
 430        else
 431                root = hists->entries_in;
 432
 433        hists->entries = RB_ROOT;
 434        next = rb_first(root);
 435
 436        hists->nr_entries = 0;
 437        hists->stats.total_period = 0;
 438        hists__reset_col_len(hists);
 439
 440        while (next != NULL) {
 441                struct hist_entry *he;
 442
 443                he = rb_entry(next, struct hist_entry, rb_node_in);
 444                next = rb_next(&he->rb_node_in);
 445
 446                insert_hist_entry_by_compute(&hists->entries, he, compute);
 447                hists__inc_nr_entries(hists, he);
 448        }
 449}
 450
 451static void hists__process(struct hists *old, struct hists *new)
 452{
 453        hists__match(new, old);
 454
 455        if (show_baseline_only)
 456                hists__baseline_only(new);
 457        else
 458                hists__link(new, old);
 459
 460        if (sort_compute) {
 461                hists__precompute(new);
 462                hists__compute_resort(new);
 463        } else {
 464                hists__output_resort(new);
 465        }
 466
 467        hists__fprintf(new, true, 0, 0, 0, stdout);
 468}
 469
 470static int __cmd_diff(void)
 471{
 472        int ret, i;
 473#define older (session[0])
 474#define newer (session[1])
 475        struct perf_session *session[2];
 476        struct perf_evlist *evlist_new, *evlist_old;
 477        struct perf_evsel *evsel;
 478        bool first = true;
 479
 480        older = perf_session__new(input_old, O_RDONLY, force, false,
 481                                  &tool);
 482        newer = perf_session__new(input_new, O_RDONLY, force, false,
 483                                  &tool);
 484        if (session[0] == NULL || session[1] == NULL)
 485                return -ENOMEM;
 486
 487        for (i = 0; i < 2; ++i) {
 488                ret = perf_session__process_events(session[i], &tool);
 489                if (ret)
 490                        goto out_delete;
 491        }
 492
 493        evlist_old = older->evlist;
 494        evlist_new = newer->evlist;
 495
 496        perf_evlist__collapse_resort(evlist_old);
 497        perf_evlist__collapse_resort(evlist_new);
 498
 499        list_for_each_entry(evsel, &evlist_new->entries, node) {
 500                struct perf_evsel *evsel_old;
 501
 502                evsel_old = evsel_match(evsel, evlist_old);
 503                if (!evsel_old)
 504                        continue;
 505
 506                fprintf(stdout, "%s# Event '%s'\n#\n", first ? "" : "\n",
 507                        perf_evsel__name(evsel));
 508
 509                first = false;
 510
 511                hists__process(&evsel_old->hists, &evsel->hists);
 512        }
 513
 514out_delete:
 515        for (i = 0; i < 2; ++i)
 516                perf_session__delete(session[i]);
 517        return ret;
 518#undef older
 519#undef newer
 520}
 521
 522static const char * const diff_usage[] = {
 523        "perf diff [<options>] [old_file] [new_file]",
 524        NULL,
 525};
 526
 527static const struct option options[] = {
 528        OPT_INCR('v', "verbose", &verbose,
 529                    "be more verbose (show symbol address, etc)"),
 530        OPT_BOOLEAN('b', "baseline-only", &show_baseline_only,
 531                    "Show only items with match in baseline"),
 532        OPT_CALLBACK('c', "compute", &compute,
 533                     "delta,ratio,wdiff:w1,w2 (default delta)",
 534                     "Entries differential computation selection",
 535                     setup_compute),
 536        OPT_BOOLEAN('p', "period", &show_period,
 537                    "Show period values."),
 538        OPT_BOOLEAN('F', "formula", &show_formula,
 539                    "Show formula."),
 540        OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 541                    "dump raw trace in ASCII"),
 542        OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
 543        OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
 544                    "load module symbols - WARNING: use only with -k and LIVE kernel"),
 545        OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
 546                   "only consider symbols in these dsos"),
 547        OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
 548                   "only consider symbols in these comms"),
 549        OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
 550                   "only consider these symbols"),
 551        OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
 552                   "sort by key(s): pid, comm, dso, symbol, parent"),
 553        OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
 554                   "separator for columns, no spaces will be added between "
 555                   "columns '.' is reserved."),
 556        OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
 557                    "Look for files with symbols relative to this directory"),
 558        OPT_END()
 559};
 560
 561static void ui_init(void)
 562{
 563        /*
 564         * Display baseline/delta/ratio
 565         * formula/periods columns.
 566         */
 567        perf_hpp__column_enable(PERF_HPP__BASELINE);
 568
 569        switch (compute) {
 570        case COMPUTE_DELTA:
 571                perf_hpp__column_enable(PERF_HPP__DELTA);
 572                break;
 573        case COMPUTE_RATIO:
 574                perf_hpp__column_enable(PERF_HPP__RATIO);
 575                break;
 576        case COMPUTE_WEIGHTED_DIFF:
 577                perf_hpp__column_enable(PERF_HPP__WEIGHTED_DIFF);
 578                break;
 579        default:
 580                BUG_ON(1);
 581        };
 582
 583        if (show_formula)
 584                perf_hpp__column_enable(PERF_HPP__FORMULA);
 585
 586        if (show_period) {
 587                perf_hpp__column_enable(PERF_HPP__PERIOD);
 588                perf_hpp__column_enable(PERF_HPP__PERIOD_BASELINE);
 589        }
 590}
 591
 592int cmd_diff(int argc, const char **argv, const char *prefix __maybe_unused)
 593{
 594        sort_order = diff__default_sort_order;
 595        argc = parse_options(argc, argv, options, diff_usage, 0);
 596        if (argc) {
 597                if (argc > 2)
 598                        usage_with_options(diff_usage, options);
 599                if (argc == 2) {
 600                        input_old = argv[0];
 601                        input_new = argv[1];
 602                } else
 603                        input_new = argv[0];
 604        } else if (symbol_conf.default_guest_vmlinux_name ||
 605                   symbol_conf.default_guest_kallsyms) {
 606                input_old = "perf.data.host";
 607                input_new = "perf.data.guest";
 608        }
 609
 610        if (symbol__init() < 0)
 611                return -1;
 612
 613        ui_init();
 614
 615        if (setup_sorting() < 0)
 616                usage_with_options(diff_usage, options);
 617
 618        setup_pager();
 619
 620        sort__setup_elide(NULL);
 621
 622        return __cmd_diff();
 623}
 624
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