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 int         force;
  22 static bool        show_percent;
  23
  24 static int perf_session__add_hist_entry(struct perf_session *self,
  25                                         struct addr_location *al, u64 count)
  26 {
  27         bool hit;
  28         struct hist_entry *he = __perf_session__add_hist_entry(self, al, NULL,
  29                                                                count, &hit);
  30         if (he == NULL)
  31                 return -ENOMEM;
  32
  33         if (hit)
  34                 he->count += count;
  35
  36         return 0;
  37 }
  38
  39 static int diff__process_sample_event(event_t *event, struct perf_session *session)
  40 {
  41         struct addr_location al;
  42         struct sample_data data = { .period = 1, };
  43
  44         dump_printf("(IP, %d): %d: %p\n", event->header.misc,
  45                     event->ip.pid, (void *)(long)event->ip.ip);
  46
  47         if (event__preprocess_sample(event, session, &al, NULL) < 0) {
  48                 pr_warning("problem processing %d event, skipping it.\n",
  49                            event->header.type);
  50                 return -1;
  51         }
  52
  53         if (al.filtered)
  54                 return 0;
  55
  56         event__parse_sample(event, session->sample_type, &data);
  57
  58         if (al.sym && perf_session__add_hist_entry(session, &al, data.period)) {
  59                 pr_warning("problem incrementing symbol count, skipping event\n");
  60                 return -1;
  61         }
  62
  63         session->events_stats.total += data.period;
  64         return 0;
  65 }
  66
  67 static struct perf_event_ops event_ops = {
  68         .process_sample_event = diff__process_sample_event,
  69         .process_mmap_event   = event__process_mmap,
  70         .process_comm_event   = event__process_comm,
  71         .process_exit_event   = event__process_task,
  72         .process_fork_event   = event__process_task,
  73         .process_lost_event   = event__process_lost,
  74 };
  75
  76 static void perf_session__insert_hist_entry_by_name(struct rb_root *root,
  77                                                     struct hist_entry *he)
  78 {
  79         struct rb_node **p = &root->rb_node;
  80         struct rb_node *parent = NULL;
  81         struct hist_entry *iter;
  82
  83         while (*p != NULL) {
  84                 int cmp;
  85                 parent = *p;
  86                 iter = rb_entry(parent, struct hist_entry, rb_node);
  87
  88                 cmp = strcmp(he->map->dso->name, iter->map->dso->name);
  89                 if (cmp > 0)
  90                         p = &(*p)->rb_left;
  91                 else if (cmp < 0)
  92                         p = &(*p)->rb_right;
  93                 else {
  94                         cmp = strcmp(he->sym->name, iter->sym->name);
  95                         if (cmp > 0)
  96                                 p = &(*p)->rb_left;
  97                         else
  98                                 p = &(*p)->rb_right;
  99                 }
 100         }
 101
 102         rb_link_node(&he->rb_node, parent, p);
 103         rb_insert_color(&he->rb_node, root);
 104 }
 105
 106 static void perf_session__resort_by_name(struct perf_session *self)
 107 {
 108         unsigned long position = 1;
 109         struct rb_root tmp = RB_ROOT;
 110         struct rb_node *next = rb_first(&self->hists);
 111
 112         while (next != NULL) {
 113                 struct hist_entry *n = rb_entry(next, struct hist_entry, rb_node);
 114
 115                 next = rb_next(&n->rb_node);
 116                 rb_erase(&n->rb_node, &self->hists);
 117                 n->position = position++;
 118                 perf_session__insert_hist_entry_by_name(&tmp, n);
 119         }
 120
 121         self->hists = tmp;
 122 }
 123
 124 static struct hist_entry *
 125 perf_session__find_hist_entry_by_name(struct perf_session *self,
 126                                       struct hist_entry *he)
 127 {
 128         struct rb_node *n = self->hists.rb_node;
 129
 130         while (n) {
 131                 struct hist_entry *iter = rb_entry(n, struct hist_entry, rb_node);
 132                 int cmp = strcmp(he->map->dso->name, iter->map->dso->name);
 133
 134                 if (cmp > 0)
 135                         n = n->rb_left;
 136                 else if (cmp < 0)
 137                         n = n->rb_right;
 138                 else {
 139                         cmp = strcmp(he->sym->name, iter->sym->name);
 140                         if (cmp > 0)
 141                                 n = n->rb_left;
 142                         else if (cmp < 0)
 143                                 n = n->rb_right;
 144                         else
 145                                 return iter;
 146                 }
 147         }
 148
 149         return NULL;
 150 }
 151
 152 static void perf_session__match_hists(struct perf_session *old_session,
 153                                       struct perf_session *new_session)
 154 {
 155         struct rb_node *nd;
 156
 157         perf_session__resort_by_name(old_session);
 158
 159         for (nd = rb_first(&new_session->hists); nd; nd = rb_next(nd)) {
 160                 struct hist_entry *pos = rb_entry(nd, struct hist_entry, rb_node);
 161                 pos->pair = perf_session__find_hist_entry_by_name(old_session, pos);
 162         }
 163 }
 164
 165 static size_t hist_entry__fprintf_matched(struct hist_entry *self,
 166                                           unsigned long pos,
 167                                           struct perf_session *session,
 168                                           struct perf_session *pair_session,
 169                                           FILE *fp)
 170 {
 171         u64 old_count = 0;
 172         char displacement[16];
 173         size_t printed;
 174
 175         if (self->pair != NULL) {
 176                 long pdiff = (long)self->pair->position - (long)pos;
 177                 old_count = self->pair->count;
 178                 if (pdiff == 0)
 179                         goto blank;
 180                 snprintf(displacement, sizeof(displacement), "%+4ld", pdiff);
 181         } else {
 182 blank:          memset(displacement, ' ', sizeof(displacement));
 183         }
 184
 185         printed = fprintf(fp, "%4lu %5.5s ", pos, displacement);
 186
 187         if (show_percent) {
 188                 double old_percent = 0, new_percent = 0, diff;
 189
 190                 if (pair_session->events_stats.total > 0)
 191                         old_percent = (old_count * 100) / pair_session->events_stats.total;
 192                 if (session->events_stats.total > 0)
 193                         new_percent = (self->count * 100) / session->events_stats.total;
 194
 195                 diff = old_percent - new_percent;
 196                 if (verbose)
 197                         printed += fprintf(fp, " %3.2f%% %3.2f%%", old_percent, new_percent);
 198
 199                 if ((u64)diff != 0)
 200                         printed += fprintf(fp, " %+4.2F%%", diff);
 201                 else
 202                         printed += fprintf(fp, "       ");
 203         } else {
 204                 if (verbose)
 205                         printed += fprintf(fp, " %9Lu %9Lu", old_count, self->count);
 206                 printed += fprintf(fp, " %+9Ld", (s64)self->count - (s64)old_count);
 207         }
 208
 209         return printed + fprintf(fp, " %25.25s   %s\n",
 210                                  self->map->dso->name, self->sym->name);
 211 }
 212
 213 static size_t perf_session__fprintf_matched_hists(struct perf_session *self,
 214                                                   struct perf_session *pair,
 215                                                   FILE *fp)
 216 {
 217         struct rb_node *nd;
 218         size_t printed = 0;
 219         unsigned long pos = 1;
 220
 221         for (nd = rb_first(&self->hists); nd; nd = rb_next(nd)) {
 222                 struct hist_entry *he = rb_entry(nd, struct hist_entry, rb_node);
 223                 printed += hist_entry__fprintf_matched(he, pos++, self, pair, fp);
 224         }
 225
 226         return printed;
 227 }
 228
 229 static int __cmd_diff(void)
 230 {
 231         int ret, i;
 232         struct perf_session *session[2];
 233
 234         session[0] = perf_session__new(input_old, O_RDONLY, force);
 235         session[1] = perf_session__new(input_new, O_RDONLY, force);
 236         if (session[0] == NULL || session[1] == NULL)
 237                 return -ENOMEM;
 238
 239         for (i = 0; i < 2; ++i) {
 240                 ret = perf_session__process_events(session[i], &event_ops);
 241                 if (ret)
 242                         goto out_delete;
 243                 perf_session__output_resort(session[i], session[i]->events_stats.total);
 244         }
 245
 246         perf_session__match_hists(session[0], session[1]);
 247         perf_session__fprintf_matched_hists(session[1], session[0], stdout);
 248 out_delete:
 249         for (i = 0; i < 2; ++i)
 250                 perf_session__delete(session[i]);
 251         return ret;
 252 }
 253
 254 static const char *const diff_usage[] = {
 255         "perf diff [<options>] [old_file] [new_file]",
 256 };
 257
 258 static const struct option options[] = {
 259         OPT_BOOLEAN('v', "verbose", &verbose,
 260                     "be more verbose (show symbol address, etc)"),
 261         OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 262                     "dump raw trace in ASCII"),
 263         OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
 264         OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
 265                     "load module symbols - WARNING: use only with -k and LIVE kernel"),
 266         OPT_BOOLEAN('p', "percentages", &show_percent,
 267                     "Don't shorten the pathnames taking into account the cwd"),
 268         OPT_BOOLEAN('P', "full-paths", &event_ops.full_paths,
 269                     "Don't shorten the pathnames taking into account the cwd"),
 270         OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
 271                    "only consider symbols in these dsos"),
 272         OPT_STRING('C', "comms", &symbol_conf.comm_list_str, "comm[,comm...]",
 273                    "only consider symbols in these comms"),
 274         OPT_STRING('S', "symbols", &symbol_conf.sym_list_str, "symbol[,symbol...]",
 275                    "only consider these symbols"),
 276         OPT_END()
 277 };
 278
 279 int cmd_diff(int argc, const char **argv, const char *prefix __used)
 280 {
 281         argc = parse_options(argc, argv, options, diff_usage, 0);
 282         if (argc) {
 283                 if (argc > 2)
 284                         usage_with_options(diff_usage, options);
 285                 if (argc == 2) {
 286                         input_old = argv[0];
 287                         input_new = argv[1];
 288                 } else
 289                         input_new = argv[0];
 290         }
 291
 292         if (symbol__init() < 0)
 293                 return -1;
 294
 295         setup_sorting(diff_usage, options);
 296         setup_pager();
 297         return __cmd_diff();
 298 }