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/session.h"
  13 #include "util/sort.h"
  14 #include "util/symbol.h"
  15 #include "util/util.h"
  16
  17 #include <stdlib.h>
  18
  19 static char const *input_old = "perf.data.old",
  20                   *input_new = "perf.data";
  21 static char       diff__default_sort_order[] = "dso,symbol";
  22 static bool  force;
  23 static bool show_displacement;
  24
  25 static int perf_session__add_hist_entry(struct perf_session *self,
  26                                         struct addr_location *al, u64 count)
  27 {
  28         if (__perf_session__add_hist_entry(&self->hists, al, NULL, count) != NULL)
  29                 return 0;
  30         return -ENOMEM;
  31 }
  32
  33 static int diff__process_sample_event(event_t *event, struct perf_session *session)
  34 {
  35         struct addr_location al;
  36         struct sample_data data = { .period = 1, };
  37
  38         dump_printf("(IP, %d): %d: %#Lx\n", event->header.misc,
  39                     event->ip.pid, event->ip.ip);
  40
  41         if (event__preprocess_sample(event, session, &al, NULL) < 0) {
  42                 pr_warning("problem processing %d event, skipping it.\n",
  43                            event->header.type);
  44                 return -1;
  45         }
  46
  47         if (al.filtered || al.sym == NULL)
  48                 return 0;
  49
  50         event__parse_sample(event, session->sample_type, &data);
  51
  52         if (perf_session__add_hist_entry(session, &al, data.period)) {
  53                 pr_warning("problem incrementing symbol count, skipping event\n");
  54                 return -1;
  55         }
  56
  57         session->events_stats.total += data.period;
  58         return 0;
  59 }
  60
  61 static struct perf_event_ops event_ops = {
  62         .sample = diff__process_sample_event,
  63         .mmap   = event__process_mmap,
  64         .comm   = event__process_comm,
  65         .exit   = event__process_task,
  66         .fork   = event__process_task,
  67         .lost   = event__process_lost,
  68 };
  69
  70 static void perf_session__insert_hist_entry_by_name(struct rb_root *root,
  71                                                     struct hist_entry *he)
  72 {
  73         struct rb_node **p = &root->rb_node;
  74         struct rb_node *parent = NULL;
  75         struct hist_entry *iter;
  76
  77         while (*p != NULL) {
  78                 parent = *p;
  79                 iter = rb_entry(parent, struct hist_entry, rb_node);
  80                 if (hist_entry__cmp(he, iter) < 0)
  81                         p = &(*p)->rb_left;
  82                 else
  83                         p = &(*p)->rb_right;
  84         }
  85
  86         rb_link_node(&he->rb_node, parent, p);
  87         rb_insert_color(&he->rb_node, root);
  88 }
  89
  90 static void perf_session__resort_hist_entries(struct perf_session *self)
  91 {
  92         unsigned long position = 1;
  93         struct rb_root tmp = RB_ROOT;
  94         struct rb_node *next = rb_first(&self->hists);
  95
  96         while (next != NULL) {
  97                 struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node);
  98
  99                 next = rb_next(&n->rb_node);
 100                 rb_erase(&n->rb_node, &self->hists);
 101                 n->position = position++;
 102                 perf_session__insert_hist_entry_by_name(&tmp, n);
 103         }
 104
 105         self->hists = tmp;
 106 }
 107
 108 static void perf_session__set_hist_entries_positions(struct perf_session *self)
 109 {
 110         perf_session__output_resort(&self->hists, self->events_stats.total);
 111         perf_session__resort_hist_entries(self);
 112 }
 113
 114 static struct hist_entry *
 115 perf_session__find_hist_entry(struct perf_session *self,
 116                               struct hist_entry *he)
 117 {
 118         struct rb_node *n = self->hists.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
 135 static void perf_session__match_hists(struct perf_session *old_session,
 136                                       struct perf_session *new_session)
 137 {
 138         struct rb_node *nd;
 139
 140         for (nd = rb_first(&new_session->hists); nd; nd = rb_next(nd)) {
 141                 struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node);
 142                 pos->pair = perf_session__find_hist_entry(old_session, pos);
 143         }
 144 }
 145
 146 static int __cmd_diff(void)
 147 {
 148         int ret, i;
 149         struct perf_session *session[2];
 150
 151         session[0] = perf_session__new(input_old, O_RDONLY, force, false);
 152         session[1] = perf_session__new(input_new, O_RDONLY, force, false);
 153         if (session[0] == NULL || session[1] == NULL)
 154                 return -ENOMEM;
 155
 156         for (i = 0; i < 2; ++i) {
 157                 ret = perf_session__process_events(session[i], &event_ops);
 158                 if (ret)
 159                         goto out_delete;
 160         }
 161
 162         perf_session__output_resort(&session[1]->hists,
 163                                     session[1]->events_stats.total);
 164         if (show_displacement)
 165                 perf_session__set_hist_entries_positions(session[0]);
 166
 167         perf_session__match_hists(session[0], session[1]);
 168         perf_session__fprintf_hists(&session[1]->hists, session[0],
 169                                     show_displacement, stdout,
 170                                     session[1]->events_stats.total);
 171 out_delete:
 172         for (i = 0; i < 2; ++i)
 173                 perf_session__delete(session[i]);
 174         return ret;
 175 }
 176
 177 static const char * const diff_usage[] = {
 178         "perf diff [<options>] [old_file] [new_file]",
 179         NULL,
 180 };
 181
 182 static const struct option options[] = {
 183         OPT_INCR('v', "verbose", &verbose,
 184                     "be more verbose (show symbol address, etc)"),
 185         OPT_BOOLEAN('m', "displacement", &show_displacement,
 186                     "Show position displacement relative to baseline"),
 187         OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 188                     "dump raw trace in ASCII"),
 189         OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
 190         OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
 191                     "load module symbols - WARNING: use only with -k and LIVE kernel"),
 192         OPT_BOOLEAN('P', "full-paths", &symbol_conf.full_paths,
 193                     "Don't shorten the pathnames taking into account the cwd"),
 194         OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
 195                    "only consider symbols in these dsos"),
 196         OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
 197                    "only consider symbols in these comms"),
 198         OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
 199                    "only consider these symbols"),
 200         OPT_STRING('s', "sort", &sort_order, "key[,key2...]",
 201                    "sort by key(s): pid, comm, dso, symbol, parent"),
 202         OPT_STRING('t', "field-separator", &symbol_conf.field_sep, "separator",
 203                    "separator for columns, no spaces will be added between "
 204                    "columns '.' is reserved."),
 205         OPT_END()
 206 };
 207
 208 int cmd_diff(int argc, const char **argv, const char *prefix __used)
 209 {
 210         sort_order = diff__default_sort_order;
 211         argc = parse_options(argc, argv, options, diff_usage, 0);
 212         if (argc) {
 213                 if (argc > 2)
 214                         usage_with_options(diff_usage, options);
 215                 if (argc == 2) {
 216                         input_old = argv[0];
 217                         input_new = argv[1];
 218                 } else
 219                         input_new = argv[0];
 220         } else if (symbol_conf.default_guest_vmlinux_name ||
 221                    symbol_conf.default_guest_kallsyms) {
 222                 input_old = "perf.data.host";
 223                 input_new = "perf.data.guest";
 224         }
 225
 226         symbol_conf.exclude_other = false;
 227         if (symbol__init() < 0)
 228                 return -1;
 229
 230         setup_sorting(diff_usage, options);
 231         setup_pager();
 232
 233         sort_entry__setup_elide(&sort_dso, symbol_conf.dso_list, "dso", NULL);
 234         sort_entry__setup_elide(&sort_comm, symbol_conf.comm_list, "comm", NULL);
 235         sort_entry__setup_elide(&sort_sym, symbol_conf.sym_list, "symbol", NULL);
 236
 237         return __cmd_diff();
 238 }