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_displacement;
  27
  28static int hists__add_entry(struct hists *self,
  29                            struct addr_location *al, u64 period)
  30{
  31        if (__hists__add_entry(self, al, NULL, period) != NULL)
  32                return 0;
  33        return -ENOMEM;
  34}
  35
  36static int diff__process_sample_event(struct perf_tool *tool __maybe_unused,
  37                                      union perf_event *event,
  38                                      struct perf_sample *sample,
  39                                      struct perf_evsel *evsel,
  40                                      struct machine *machine)
  41{
  42        struct addr_location al;
  43
  44        if (perf_event__preprocess_sample(event, machine, &al, sample, NULL) < 0) {
  45                pr_warning("problem processing %d event, skipping it.\n",
  46                           event->header.type);
  47                return -1;
  48        }
  49
  50        if (al.filtered || al.sym == NULL)
  51                return 0;
  52
  53        if (hists__add_entry(&evsel->hists, &al, sample->period)) {
  54                pr_warning("problem incrementing symbol period, skipping event\n");
  55                return -1;
  56        }
  57
  58        evsel->hists.stats.total_period += sample->period;
  59        return 0;
  60}
  61
  62static struct perf_tool tool = {
  63        .sample = diff__process_sample_event,
  64        .mmap   = perf_event__process_mmap,
  65        .comm   = perf_event__process_comm,
  66        .exit   = perf_event__process_task,
  67        .fork   = perf_event__process_task,
  68        .lost   = perf_event__process_lost,
  69        .ordered_samples = true,
  70        .ordering_requires_timestamps = true,
  71};
  72
  73static void insert_hist_entry_by_name(struct rb_root *root,
  74                                      struct hist_entry *he)
  75{
  76        struct rb_node **p = &root->rb_node;
  77        struct rb_node *parent = NULL;
  78        struct hist_entry *iter;
  79
  80        while (*p != NULL) {
  81                parent = *p;
  82                iter = rb_entry(parent, struct hist_entry, rb_node);
  83                if (hist_entry__cmp(he, iter) < 0)
  84                        p = &(*p)->rb_left;
  85                else
  86                        p = &(*p)->rb_right;
  87        }
  88
  89        rb_link_node(&he->rb_node, parent, p);
  90        rb_insert_color(&he->rb_node, root);
  91}
  92
  93static void hists__name_resort(struct hists *self, bool sort)
  94{
  95        unsigned long position = 1;
  96        struct rb_root tmp = RB_ROOT;
  97        struct rb_node *next = rb_first(&self->entries);
  98
  99        while (next != NULL) {
 100                struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node);
 101
 102                next = rb_next(&n->rb_node);
 103                n->position = position++;
 104
 105                if (sort) {
 106                        rb_erase(&n->rb_node, &self->entries);
 107                        insert_hist_entry_by_name(&tmp, n);
 108                }
 109        }
 110
 111        if (sort)
 112                self->entries = tmp;
 113}
 114
 115static struct hist_entry *hists__find_entry(struct hists *self,
 116                                            struct hist_entry *he)
 117{
 118        struct rb_node *n = self->entries.rb_node;
 119
 120        while (n) {
 121                struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node);
 122                int64_t cmp = hist_entry__cmp(he, iter);
 123
 124                if (cmp < 0)
 125                        n = n->rb_left;
 126                else if (cmp > 0)
 127                        n = n->rb_right;
 128                else
 129                        return iter;
 130        }
 131
 132        return NULL;
 133}
 134
 135static void hists__match(struct hists *older, struct hists *newer)
 136{
 137        struct rb_node *nd;
 138
 139        for (nd = rb_first(&newer->entries); nd; nd = rb_next(nd)) {
 140                struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node);
 141                pos->pair = hists__find_entry(older, pos);
 142        }
 143}
 144
 145static struct perf_evsel *evsel_match(struct perf_evsel *evsel,
 146                                      struct perf_evlist *evlist)
 147{
 148        struct perf_evsel *e;
 149
 150        list_for_each_entry(e, &evlist->entries, node)
 151                if (perf_evsel__match2(evsel, e))
 152                        return e;
 153
 154        return NULL;
 155}
 156
 157static void perf_evlist__resort_hists(struct perf_evlist *evlist, bool name)
 158{
 159        struct perf_evsel *evsel;
 160
 161        list_for_each_entry(evsel, &evlist->entries, node) {
 162                struct hists *hists = &evsel->hists;
 163
 164                hists__output_resort(hists);
 165
 166                /*
 167                 * The hists__name_resort only sets possition
 168                 * if name is false.
 169                 */
 170                if (name || ((!name) && show_displacement))
 171                        hists__name_resort(hists, name);
 172        }
 173}
 174
 175static int __cmd_diff(void)
 176{
 177        int ret, i;
 178#define older (session[0])
 179#define newer (session[1])
 180        struct perf_session *session[2];
 181        struct perf_evlist *evlist_new, *evlist_old;
 182        struct perf_evsel *evsel;
 183        bool first = true;
 184
 185        older = perf_session__new(input_old, O_RDONLY, force, false,
 186                                  &tool);
 187        newer = perf_session__new(input_new, O_RDONLY, force, false,
 188                                  &tool);
 189        if (session[0] == NULL || session[1] == NULL)
 190                return -ENOMEM;
 191
 192        for (i = 0; i < 2; ++i) {
 193                ret = perf_session__process_events(session[i], &tool);
 194                if (ret)
 195                        goto out_delete;
 196        }
 197
 198        evlist_old = older->evlist;
 199        evlist_new = newer->evlist;
 200
 201        perf_evlist__resort_hists(evlist_old, true);
 202        perf_evlist__resort_hists(evlist_new, false);
 203
 204        list_for_each_entry(evsel, &evlist_new->entries, node) {
 205                struct perf_evsel *evsel_old;
 206
 207                evsel_old = evsel_match(evsel, evlist_old);
 208                if (!evsel_old)
 209                        continue;
 210
 211                fprintf(stdout, "%s# Event '%s'\n#\n", first ? "" : "\n",
 212                        perf_evsel__name(evsel));
 213
 214                first = false;
 215
 216                hists__match(&evsel_old->hists, &evsel->hists);
 217                hists__fprintf(&evsel->hists, true, 0, 0, stdout);
 218        }
 219
 220out_delete:
 221        for (i = 0; i < 2; ++i)
 222                perf_session__delete(session[i]);
 223        return ret;
 224#undef older
 225#undef newer
 226}
 227
 228static const char * const diff_usage[] = {
 229        "perf diff [<options>] [old_file] [new_file]",
 230        NULL,
 231};
 232
 233static const struct option options[] = {
 234        OPT_INCR('v', "verbose", &verbose,
 235                    "be more verbose (show symbol address, etc)"),
 236        OPT_BOOLEAN('M', "displacement", &show_displacement,
 237                    "Show position displacement relative to baseline"),
 238        OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 239                    "dump raw trace in ASCII"),
 240        OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
 241        OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
 242                    "load module symbols - WARNING: use only with -k and LIVE kernel"),
 243        OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
 244                   "only consider symbols in these dsos"),
 245        OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
 246                   "only consider symbols in these comms"),
 247        OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
 248                   "only consider these symbols"),
 249        OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
 250                   "sort by key(s): pid, comm, dso, symbol, parent"),
 251        OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
 252                   "separator for columns, no spaces will be added between "
 253                   "columns '.' is reserved."),
 254        OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
 255                    "Look for files with symbols relative to this directory"),
 256        OPT_END()
 257};
 258
 259static void ui_init(void)
 260{
 261        perf_hpp__init();
 262
 263        /* No overhead column. */
 264        perf_hpp__column_enable(PERF_HPP__OVERHEAD, false);
 265
 266        /* Display baseline/delta/displacement columns. */
 267        perf_hpp__column_enable(PERF_HPP__BASELINE, true);
 268        perf_hpp__column_enable(PERF_HPP__DELTA, true);
 269
 270        if (show_displacement)
 271                perf_hpp__column_enable(PERF_HPP__DISPL, true);
 272}
 273
 274int cmd_diff(int argc, const char **argv, const char *prefix __maybe_unused)
 275{
 276        sort_order = diff__default_sort_order;
 277        argc = parse_options(argc, argv, options, diff_usage, 0);
 278        if (argc) {
 279                if (argc > 2)
 280                        usage_with_options(diff_usage, options);
 281                if (argc == 2) {
 282                        input_old = argv[0];
 283                        input_new = argv[1];
 284                } else
 285                        input_new = argv[0];
 286        } else if (symbol_conf.default_guest_vmlinux_name ||
 287                   symbol_conf.default_guest_kallsyms) {
 288                input_old = "perf.data.host";
 289                input_new = "perf.data.guest";
 290        }
 291
 292        symbol_conf.exclude_other = false;
 293        if (symbol__init() < 0)
 294                return -1;
 295
 296        ui_init();
 297
 298        setup_sorting(diff_usage, options);
 299        setup_pager();
 300
 301        sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
 302        sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
 303        sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
 304
 305        return __cmd_diff();
 306}
 307
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