tools/perf/util/stat.c

   1 #include <errno.h>
   2 #include <inttypes.h>
   3 #include <math.h>
   4 #include "stat.h"
   5 #include "evlist.h"
   6 #include "evsel.h"
   7 #include "thread_map.h"
   8
   9 void update_stats(struct stats *stats, u64 val)
  10 {
  11         double delta;
  12
  13         stats->n++;
  14         delta = val - stats->mean;
  15         stats->mean += delta / stats->n;
  16         stats->M2 += delta*(val - stats->mean);
  17
  18         if (val > stats->max)
  19                 stats->max = val;
  20
  21         if (val < stats->min)
  22                 stats->min = val;
  23 }
  24
  25 double avg_stats(struct stats *stats)
  26 {
  27         return stats->mean;
  28 }
  29
  30 /*
  31  * http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance
  32  *
  33  *       (\Sum n_i^2) - ((\Sum n_i)^2)/n
  34  * s^2 = -------------------------------
  35  *                  n - 1
  36  *
  37  * http://en.wikipedia.org/wiki/Stddev
  38  *
  39  * The std dev of the mean is related to the std dev by:
  40  *
  41  *             s
  42  * s_mean = -------
  43  *          sqrt(n)
  44  *
  45  */
  46 double stddev_stats(struct stats *stats)
  47 {
  48         double variance, variance_mean;
  49
  50         if (stats->n < 2)
  51                 return 0.0;
  52
  53         variance = stats->M2 / (stats->n - 1);
  54         variance_mean = variance / stats->n;
  55
  56         return sqrt(variance_mean);
  57 }
  58
  59 double rel_stddev_stats(double stddev, double avg)
  60 {
  61         double pct = 0.0;
  62
  63         if (avg)
  64                 pct = 100.0 * stddev/avg;
  65
  66         return pct;
  67 }
  68
  69 bool __perf_evsel_stat__is(struct perf_evsel *evsel,
  70                            enum perf_stat_evsel_id id)
  71 {
  72         struct perf_stat_evsel *ps = evsel->priv;
  73
  74         return ps->id == id;
  75 }
  76
  77 #define ID(id, name) [PERF_STAT_EVSEL_ID__##id] = #name
  78 static const char *id_str[PERF_STAT_EVSEL_ID__MAX] = {
  79         ID(NONE,                x),
  80         ID(CYCLES_IN_TX,        cpu/cycles-t/),
  81         ID(TRANSACTION_START,   cpu/tx-start/),
  82         ID(ELISION_START,       cpu/el-start/),
  83         ID(CYCLES_IN_TX_CP,     cpu/cycles-ct/),
  84         ID(TOPDOWN_TOTAL_SLOTS, topdown-total-slots),
  85         ID(TOPDOWN_SLOTS_ISSUED, topdown-slots-issued),
  86         ID(TOPDOWN_SLOTS_RETIRED, topdown-slots-retired),
  87         ID(TOPDOWN_FETCH_BUBBLES, topdown-fetch-bubbles),
  88         ID(TOPDOWN_RECOVERY_BUBBLES, topdown-recovery-bubbles),
  89 };
  90 #undef ID
  91
  92 void perf_stat_evsel_id_init(struct perf_evsel *evsel)
  93 {
  94         struct perf_stat_evsel *ps = evsel->priv;
  95         int i;
  96
  97         /* ps->id is 0 hence PERF_STAT_EVSEL_ID__NONE by default */
  98
  99         for (i = 0; i < PERF_STAT_EVSEL_ID__MAX; i++) {
 100                 if (!strcmp(perf_evsel__name(evsel), id_str[i])) {
 101                         ps->id = i;
 102                         break;
 103                 }
 104         }
 105 }
 106
 107 static void perf_evsel__reset_stat_priv(struct perf_evsel *evsel)
 108 {
 109         int i;
 110         struct perf_stat_evsel *ps = evsel->priv;
 111
 112         for (i = 0; i < 3; i++)
 113                 init_stats(&ps->res_stats[i]);
 114
 115         perf_stat_evsel_id_init(evsel);
 116 }
 117
 118 static int perf_evsel__alloc_stat_priv(struct perf_evsel *evsel)
 119 {
 120         evsel->priv = zalloc(sizeof(struct perf_stat_evsel));
 121         if (evsel->priv == NULL)
 122                 return -ENOMEM;
 123         perf_evsel__reset_stat_priv(evsel);
 124         return 0;
 125 }
 126
 127 static void perf_evsel__free_stat_priv(struct perf_evsel *evsel)
 128 {
 129         zfree(&evsel->priv);
 130 }
 131
 132 static int perf_evsel__alloc_prev_raw_counts(struct perf_evsel *evsel,
 133                                              int ncpus, int nthreads)
 134 {
 135         struct perf_counts *counts;
 136
 137         counts = perf_counts__new(ncpus, nthreads);
 138         if (counts)
 139                 evsel->prev_raw_counts = counts;
 140
 141         return counts ? 0 : -ENOMEM;
 142 }
 143
 144 static void perf_evsel__free_prev_raw_counts(struct perf_evsel *evsel)
 145 {
 146         perf_counts__delete(evsel->prev_raw_counts);
 147         evsel->prev_raw_counts = NULL;
 148 }
 149
 150 static int perf_evsel__alloc_stats(struct perf_evsel *evsel, bool alloc_raw)
 151 {
 152         int ncpus = perf_evsel__nr_cpus(evsel);
 153         int nthreads = thread_map__nr(evsel->threads);
 154
 155         if (perf_evsel__alloc_stat_priv(evsel) < 0 ||
 156             perf_evsel__alloc_counts(evsel, ncpus, nthreads) < 0 ||
 157             (alloc_raw && perf_evsel__alloc_prev_raw_counts(evsel, ncpus, nthreads) < 0))
 158                 return -ENOMEM;
 159
 160         return 0;
 161 }
 162
 163 int perf_evlist__alloc_stats(struct perf_evlist *evlist, bool alloc_raw)
 164 {
 165         struct perf_evsel *evsel;
 166
 167         evlist__for_each_entry(evlist, evsel) {
 168                 if (perf_evsel__alloc_stats(evsel, alloc_raw))
 169                         goto out_free;
 170         }
 171
 172         return 0;
 173
 174 out_free:
 175         perf_evlist__free_stats(evlist);
 176         return -1;
 177 }
 178
 179 void perf_evlist__free_stats(struct perf_evlist *evlist)
 180 {
 181         struct perf_evsel *evsel;
 182
 183         evlist__for_each_entry(evlist, evsel) {
 184                 perf_evsel__free_stat_priv(evsel);
 185                 perf_evsel__free_counts(evsel);
 186                 perf_evsel__free_prev_raw_counts(evsel);
 187         }
 188 }
 189
 190 void perf_evlist__reset_stats(struct perf_evlist *evlist)
 191 {
 192         struct perf_evsel *evsel;
 193
 194         evlist__for_each_entry(evlist, evsel) {
 195                 perf_evsel__reset_stat_priv(evsel);
 196                 perf_evsel__reset_counts(evsel);
 197         }
 198 }
 199
 200 static void zero_per_pkg(struct perf_evsel *counter)
 201 {
 202         if (counter->per_pkg_mask)
 203                 memset(counter->per_pkg_mask, 0, MAX_NR_CPUS);
 204 }
 205
 206 static int check_per_pkg(struct perf_evsel *counter,
 207                          struct perf_counts_values *vals, int cpu, bool *skip)
 208 {
 209         unsigned long *mask = counter->per_pkg_mask;
 210         struct cpu_map *cpus = perf_evsel__cpus(counter);
 211         int s;
 212
 213         *skip = false;
 214
 215         if (!counter->per_pkg)
 216                 return 0;
 217
 218         if (cpu_map__empty(cpus))
 219                 return 0;
 220
 221         if (!mask) {
 222                 mask = zalloc(MAX_NR_CPUS);
 223                 if (!mask)
 224                         return -ENOMEM;
 225
 226                 counter->per_pkg_mask = mask;
 227         }
 228
 229         /*
 230          * we do not consider an event that has not run as a good
 231          * instance to mark a package as used (skip=1). Otherwise
 232          * we may run into a situation where the first CPU in a package
 233          * is not running anything, yet the second is, and this function
 234          * would mark the package as used after the first CPU and would
 235          * not read the values from the second CPU.
 236          */
 237         if (!(vals->run && vals->ena))
 238                 return 0;
 239
 240         s = cpu_map__get_socket(cpus, cpu, NULL);
 241         if (s < 0)
 242                 return -1;
 243
 244         *skip = test_and_set_bit(s, mask) == 1;
 245         return 0;
 246 }
 247
 248 static int
 249 process_counter_values(struct perf_stat_config *config, struct perf_evsel *evsel,
 250                        int cpu, int thread,
 251                        struct perf_counts_values *count)
 252 {
 253         struct perf_counts_values *aggr = &evsel->counts->aggr;
 254         static struct perf_counts_values zero;
 255         bool skip = false;
 256
 257         if (check_per_pkg(evsel, count, cpu, &skip)) {
 258                 pr_err("failed to read per-pkg counter\n");
 259                 return -1;
 260         }
 261
 262         if (skip)
 263                 count = &zero;
 264
 265         switch (config->aggr_mode) {
 266         case AGGR_THREAD:
 267         case AGGR_CORE:
 268         case AGGR_SOCKET:
 269         case AGGR_NONE:
 270                 if (!evsel->snapshot)
 271                         perf_evsel__compute_deltas(evsel, cpu, thread, count);
 272                 perf_counts_values__scale(count, config->scale, NULL);
 273                 if (config->aggr_mode == AGGR_NONE)
 274                         perf_stat__update_shadow_stats(evsel, count->values, cpu);
 275                 break;
 276         case AGGR_GLOBAL:
 277                 aggr->val += count->val;
 278                 if (config->scale) {
 279                         aggr->ena += count->ena;
 280                         aggr->run += count->run;
 281                 }
 282         case AGGR_UNSET:
 283         default:
 284                 break;
 285         }
 286
 287         return 0;
 288 }
 289
 290 static int process_counter_maps(struct perf_stat_config *config,
 291                                 struct perf_evsel *counter)
 292 {
 293         int nthreads = thread_map__nr(counter->threads);
 294         int ncpus = perf_evsel__nr_cpus(counter);
 295         int cpu, thread;
 296
 297         if (counter->system_wide)
 298                 nthreads = 1;
 299
 300         for (thread = 0; thread < nthreads; thread++) {
 301                 for (cpu = 0; cpu < ncpus; cpu++) {
 302                         if (process_counter_values(config, counter, cpu, thread,
 303                                                    perf_counts(counter->counts, cpu, thread)))
 304                                 return -1;
 305                 }
 306         }
 307
 308         return 0;
 309 }
 310
 311 int perf_stat_process_counter(struct perf_stat_config *config,
 312                               struct perf_evsel *counter)
 313 {
 314         struct perf_counts_values *aggr = &counter->counts->aggr;
 315         struct perf_stat_evsel *ps = counter->priv;
 316         u64 *count = counter->counts->aggr.values;
 317         u64 val;
 318         int i, ret;
 319
 320         aggr->val = aggr->ena = aggr->run = 0;
 321
 322         /*
 323          * We calculate counter's data every interval,
 324          * and the display code shows ps->res_stats
 325          * avg value. We need to zero the stats for
 326          * interval mode, otherwise overall avg running
 327          * averages will be shown for each interval.
 328          */
 329         if (config->interval)
 330                 init_stats(ps->res_stats);
 331
 332         if (counter->per_pkg)
 333                 zero_per_pkg(counter);
 334
 335         ret = process_counter_maps(config, counter);
 336         if (ret)
 337                 return ret;
 338
 339         if (config->aggr_mode != AGGR_GLOBAL)
 340                 return 0;
 341
 342         if (!counter->snapshot)
 343                 perf_evsel__compute_deltas(counter, -1, -1, aggr);
 344         perf_counts_values__scale(aggr, config->scale, &counter->counts->scaled);
 345
 346         for (i = 0; i < 3; i++)
 347                 update_stats(&ps->res_stats[i], count[i]);
 348
 349         if (verbose > 0) {
 350                 fprintf(config->output, "%s: %" PRIu64 " %" PRIu64 " %" PRIu64 "\n",
 351                         perf_evsel__name(counter), count[0], count[1], count[2]);
 352         }
 353
 354         /*
 355          * Save the full runtime - to allow normalization during printout:
 356          */
 357         val = counter->scale * *count;
 358         perf_stat__update_shadow_stats(counter, &val, 0);
 359
 360         return 0;
 361 }
 362
 363 int perf_event__process_stat_event(struct perf_tool *tool __maybe_unused,
 364                                    union perf_event *event,
 365                                    struct perf_session *session)
 366 {
 367         struct perf_counts_values count;
 368         struct stat_event *st = &event->stat;
 369         struct perf_evsel *counter;
 370
 371         count.val = st->val;
 372         count.ena = st->ena;
 373         count.run = st->run;
 374
 375         counter = perf_evlist__id2evsel(session->evlist, st->id);
 376         if (!counter) {
 377                 pr_err("Failed to resolve counter for stat event.\n");
 378                 return -EINVAL;
 379         }
 380
 381         *perf_counts(counter->counts, st->cpu, st->thread) = count;
 382         counter->supported = true;
 383         return 0;
 384 }
 385
 386 size_t perf_event__fprintf_stat(union perf_event *event, FILE *fp)
 387 {
 388         struct stat_event *st = (struct stat_event *) event;
 389         size_t ret;
 390
 391         ret  = fprintf(fp, "\n... id %" PRIu64 ", cpu %d, thread %d\n",
 392                        st->id, st->cpu, st->thread);
 393         ret += fprintf(fp, "... value %" PRIu64 ", enabled %" PRIu64 ", running %" PRIu64 "\n",
 394                        st->val, st->ena, st->run);
 395
 396         return ret;
 397 }
 398
 399 size_t perf_event__fprintf_stat_round(union perf_event *event, FILE *fp)
 400 {
 401         struct stat_round_event *rd = (struct stat_round_event *)event;
 402         size_t ret;
 403
 404         ret = fprintf(fp, "\n... time %" PRIu64 ", type %s\n", rd->time,
 405                       rd->type == PERF_STAT_ROUND_TYPE__FINAL ? "FINAL" : "INTERVAL");
 406
 407         return ret;
 408 }
 409
 410 size_t perf_event__fprintf_stat_config(union perf_event *event, FILE *fp)
 411 {
 412         struct perf_stat_config sc;
 413         size_t ret;
 414
 415         perf_event__read_stat_config(&sc, &event->stat_config);
 416
 417         ret  = fprintf(fp, "\n");
 418         ret += fprintf(fp, "... aggr_mode %d\n", sc.aggr_mode);
 419         ret += fprintf(fp, "... scale     %d\n", sc.scale);
 420         ret += fprintf(fp, "... interval  %u\n", sc.interval);
 421
 422         return ret;
 423 }