tools/perf/util/stat.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <errno.h>
   3 #include <inttypes.h>
   4 #include <math.h>
   5 #include "stat.h"
   6 #include "evlist.h"
   7 #include "evsel.h"
   8 #include "thread_map.h"
   9
  10 void update_stats(struct stats *stats, u64 val)
  11 {
  12         double delta;
  13
  14         stats->n++;
  15         delta = val - stats->mean;
  16         stats->mean += delta / stats->n;
  17         stats->M2 += delta*(val - stats->mean);
  18
  19         if (val > stats->max)
  20                 stats->max = val;
  21
  22         if (val < stats->min)
  23                 stats->min = val;
  24 }
  25
  26 double avg_stats(struct stats *stats)
  27 {
  28         return stats->mean;
  29 }
  30
  31 /*
  32  * http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance
  33  *
  34  *       (\Sum n_i^2) - ((\Sum n_i)^2)/n
  35  * s^2 = -------------------------------
  36  *                  n - 1
  37  *
  38  * http://en.wikipedia.org/wiki/Stddev
  39  *
  40  * The std dev of the mean is related to the std dev by:
  41  *
  42  *             s
  43  * s_mean = -------
  44  *          sqrt(n)
  45  *
  46  */
  47 double stddev_stats(struct stats *stats)
  48 {
  49         double variance, variance_mean;
  50
  51         if (stats->n < 2)
  52                 return 0.0;
  53
  54         variance = stats->M2 / (stats->n - 1);
  55         variance_mean = variance / stats->n;
  56
  57         return sqrt(variance_mean);
  58 }
  59
  60 double rel_stddev_stats(double stddev, double avg)
  61 {
  62         double pct = 0.0;
  63
  64         if (avg)
  65                 pct = 100.0 * stddev/avg;
  66
  67         return pct;
  68 }
  69
  70 bool __perf_evsel_stat__is(struct perf_evsel *evsel,
  71                            enum perf_stat_evsel_id id)
  72 {
  73         struct perf_stat_evsel *ps = evsel->stats;
  74
  75         return ps->id == id;
  76 }
  77
  78 #define ID(id, name) [PERF_STAT_EVSEL_ID__##id] = #name
  79 static const char *id_str[PERF_STAT_EVSEL_ID__MAX] = {
  80         ID(NONE,                x),
  81         ID(CYCLES_IN_TX,        cpu/cycles-t/),
  82         ID(TRANSACTION_START,   cpu/tx-start/),
  83         ID(ELISION_START,       cpu/el-start/),
  84         ID(CYCLES_IN_TX_CP,     cpu/cycles-ct/),
  85         ID(TOPDOWN_TOTAL_SLOTS, topdown-total-slots),
  86         ID(TOPDOWN_SLOTS_ISSUED, topdown-slots-issued),
  87         ID(TOPDOWN_SLOTS_RETIRED, topdown-slots-retired),
  88         ID(TOPDOWN_FETCH_BUBBLES, topdown-fetch-bubbles),
  89         ID(TOPDOWN_RECOVERY_BUBBLES, topdown-recovery-bubbles),
  90         ID(SMI_NUM, msr/smi/),
  91         ID(APERF, msr/aperf/),
  92 };
  93 #undef ID
  94
  95 static void perf_stat_evsel_id_init(struct perf_evsel *evsel)
  96 {
  97         struct perf_stat_evsel *ps = evsel->stats;
  98         int i;
  99
 100         /* ps->id is 0 hence PERF_STAT_EVSEL_ID__NONE by default */
 101
 102         for (i = 0; i < PERF_STAT_EVSEL_ID__MAX; i++) {
 103                 if (!strcmp(perf_evsel__name(evsel), id_str[i])) {
 104                         ps->id = i;
 105                         break;
 106                 }
 107         }
 108 }
 109
 110 static void perf_evsel__reset_stat_priv(struct perf_evsel *evsel)
 111 {
 112         int i;
 113         struct perf_stat_evsel *ps = evsel->stats;
 114
 115         for (i = 0; i < 3; i++)
 116                 init_stats(&ps->res_stats[i]);
 117
 118         perf_stat_evsel_id_init(evsel);
 119 }
 120
 121 static int perf_evsel__alloc_stat_priv(struct perf_evsel *evsel)
 122 {
 123         evsel->stats = zalloc(sizeof(struct perf_stat_evsel));
 124         if (evsel->stats == NULL)
 125                 return -ENOMEM;
 126         perf_evsel__reset_stat_priv(evsel);
 127         return 0;
 128 }
 129
 130 static void perf_evsel__free_stat_priv(struct perf_evsel *evsel)
 131 {
 132         struct perf_stat_evsel *ps = evsel->stats;
 133
 134         if (ps)
 135                 free(ps->group_data);
 136         zfree(&evsel->stats);
 137 }
 138
 139 static int perf_evsel__alloc_prev_raw_counts(struct perf_evsel *evsel,
 140                                              int ncpus, int nthreads)
 141 {
 142         struct perf_counts *counts;
 143
 144         counts = perf_counts__new(ncpus, nthreads);
 145         if (counts)
 146                 evsel->prev_raw_counts = counts;
 147
 148         return counts ? 0 : -ENOMEM;
 149 }
 150
 151 static void perf_evsel__free_prev_raw_counts(struct perf_evsel *evsel)
 152 {
 153         perf_counts__delete(evsel->prev_raw_counts);
 154         evsel->prev_raw_counts = NULL;
 155 }
 156
 157 static int perf_evsel__alloc_stats(struct perf_evsel *evsel, bool alloc_raw)
 158 {
 159         int ncpus = perf_evsel__nr_cpus(evsel);
 160         int nthreads = thread_map__nr(evsel->threads);
 161
 162         if (perf_evsel__alloc_stat_priv(evsel) < 0 ||
 163             perf_evsel__alloc_counts(evsel, ncpus, nthreads) < 0 ||
 164             (alloc_raw && perf_evsel__alloc_prev_raw_counts(evsel, ncpus, nthreads) < 0))
 165                 return -ENOMEM;
 166
 167         return 0;
 168 }
 169
 170 int perf_evlist__alloc_stats(struct perf_evlist *evlist, bool alloc_raw)
 171 {
 172         struct perf_evsel *evsel;
 173
 174         evlist__for_each_entry(evlist, evsel) {
 175                 if (perf_evsel__alloc_stats(evsel, alloc_raw))
 176                         goto out_free;
 177         }
 178
 179         return 0;
 180
 181 out_free:
 182         perf_evlist__free_stats(evlist);
 183         return -1;
 184 }
 185
 186 void perf_evlist__free_stats(struct perf_evlist *evlist)
 187 {
 188         struct perf_evsel *evsel;
 189
 190         evlist__for_each_entry(evlist, evsel) {
 191                 perf_evsel__free_stat_priv(evsel);
 192                 perf_evsel__free_counts(evsel);
 193                 perf_evsel__free_prev_raw_counts(evsel);
 194         }
 195 }
 196
 197 void perf_evlist__reset_stats(struct perf_evlist *evlist)
 198 {
 199         struct perf_evsel *evsel;
 200
 201         evlist__for_each_entry(evlist, evsel) {
 202                 perf_evsel__reset_stat_priv(evsel);
 203                 perf_evsel__reset_counts(evsel);
 204         }
 205 }
 206
 207 static void zero_per_pkg(struct perf_evsel *counter)
 208 {
 209         if (counter->per_pkg_mask)
 210                 memset(counter->per_pkg_mask, 0, MAX_NR_CPUS);
 211 }
 212
 213 static int check_per_pkg(struct perf_evsel *counter,
 214                          struct perf_counts_values *vals, int cpu, bool *skip)
 215 {
 216         unsigned long *mask = counter->per_pkg_mask;
 217         struct cpu_map *cpus = perf_evsel__cpus(counter);
 218         int s;
 219
 220         *skip = false;
 221
 222         if (!counter->per_pkg)
 223                 return 0;
 224
 225         if (cpu_map__empty(cpus))
 226                 return 0;
 227
 228         if (!mask) {
 229                 mask = zalloc(MAX_NR_CPUS);
 230                 if (!mask)
 231                         return -ENOMEM;
 232
 233                 counter->per_pkg_mask = mask;
 234         }
 235
 236         /*
 237          * we do not consider an event that has not run as a good
 238          * instance to mark a package as used (skip=1). Otherwise
 239          * we may run into a situation where the first CPU in a package
 240          * is not running anything, yet the second is, and this function
 241          * would mark the package as used after the first CPU and would
 242          * not read the values from the second CPU.
 243          */
 244         if (!(vals->run && vals->ena))
 245                 return 0;
 246
 247         s = cpu_map__get_socket(cpus, cpu, NULL);
 248         if (s < 0)
 249                 return -1;
 250
 251         *skip = test_and_set_bit(s, mask) == 1;
 252         return 0;
 253 }
 254
 255 static int
 256 process_counter_values(struct perf_stat_config *config, struct perf_evsel *evsel,
 257                        int cpu, int thread,
 258                        struct perf_counts_values *count)
 259 {
 260         struct perf_counts_values *aggr = &evsel->counts->aggr;
 261         static struct perf_counts_values zero;
 262         bool skip = false;
 263
 264         if (check_per_pkg(evsel, count, cpu, &skip)) {
 265                 pr_err("failed to read per-pkg counter\n");
 266                 return -1;
 267         }
 268
 269         if (skip)
 270                 count = &zero;
 271
 272         switch (config->aggr_mode) {
 273         case AGGR_THREAD:
 274         case AGGR_CORE:
 275         case AGGR_SOCKET:
 276         case AGGR_NONE:
 277                 if (!evsel->snapshot)
 278                         perf_evsel__compute_deltas(evsel, cpu, thread, count);
 279                 perf_counts_values__scale(count, config->scale, NULL);
 280                 if (config->aggr_mode == AGGR_NONE)
 281                         perf_stat__update_shadow_stats(evsel, count->val, cpu,
 282                                                        &rt_stat);
 283                 if (config->aggr_mode == AGGR_THREAD) {
 284                         if (config->stats)
 285                                 perf_stat__update_shadow_stats(evsel,
 286                                         count->val, 0, &config->stats[thread]);
 287                         else
 288                                 perf_stat__update_shadow_stats(evsel,
 289                                         count->val, 0, &rt_stat);
 290                 }
 291                 break;
 292         case AGGR_GLOBAL:
 293                 aggr->val += count->val;
 294                 if (config->scale) {
 295                         aggr->ena += count->ena;
 296                         aggr->run += count->run;
 297                 }
 298         case AGGR_UNSET:
 299         default:
 300                 break;
 301         }
 302
 303         return 0;
 304 }
 305
 306 static int process_counter_maps(struct perf_stat_config *config,
 307                                 struct perf_evsel *counter)
 308 {
 309         int nthreads = thread_map__nr(counter->threads);
 310         int ncpus = perf_evsel__nr_cpus(counter);
 311         int cpu, thread;
 312
 313         if (counter->system_wide)
 314                 nthreads = 1;
 315
 316         for (thread = 0; thread < nthreads; thread++) {
 317                 for (cpu = 0; cpu < ncpus; cpu++) {
 318                         if (process_counter_values(config, counter, cpu, thread,
 319                                                    perf_counts(counter->counts, cpu, thread)))
 320                                 return -1;
 321                 }
 322         }
 323
 324         return 0;
 325 }
 326
 327 int perf_stat_process_counter(struct perf_stat_config *config,
 328                               struct perf_evsel *counter)
 329 {
 330         struct perf_counts_values *aggr = &counter->counts->aggr;
 331         struct perf_stat_evsel *ps = counter->stats;
 332         u64 *count = counter->counts->aggr.values;
 333         int i, ret;
 334
 335         aggr->val = aggr->ena = aggr->run = 0;
 336
 337         /*
 338          * We calculate counter's data every interval,
 339          * and the display code shows ps->res_stats
 340          * avg value. We need to zero the stats for
 341          * interval mode, otherwise overall avg running
 342          * averages will be shown for each interval.
 343          */
 344         if (config->interval)
 345                 init_stats(ps->res_stats);
 346
 347         if (counter->per_pkg)
 348                 zero_per_pkg(counter);
 349
 350         ret = process_counter_maps(config, counter);
 351         if (ret)
 352                 return ret;
 353
 354         if (config->aggr_mode != AGGR_GLOBAL)
 355                 return 0;
 356
 357         if (!counter->snapshot)
 358                 perf_evsel__compute_deltas(counter, -1, -1, aggr);
 359         perf_counts_values__scale(aggr, config->scale, &counter->counts->scaled);
 360
 361         for (i = 0; i < 3; i++)
 362                 update_stats(&ps->res_stats[i], count[i]);
 363
 364         if (verbose > 0) {
 365                 fprintf(config->output, "%s: %" PRIu64 " %" PRIu64 " %" PRIu64 "\n",
 366                         perf_evsel__name(counter), count[0], count[1], count[2]);
 367         }
 368
 369         /*
 370          * Save the full runtime - to allow normalization during printout:
 371          */
 372         perf_stat__update_shadow_stats(counter, *count, 0, &rt_stat);
 373
 374         return 0;
 375 }
 376
 377 int perf_event__process_stat_event(struct perf_tool *tool __maybe_unused,
 378                                    union perf_event *event,
 379                                    struct perf_session *session)
 380 {
 381         struct perf_counts_values count;
 382         struct stat_event *st = &event->stat;
 383         struct perf_evsel *counter;
 384
 385         count.val = st->val;
 386         count.ena = st->ena;
 387         count.run = st->run;
 388
 389         counter = perf_evlist__id2evsel(session->evlist, st->id);
 390         if (!counter) {
 391                 pr_err("Failed to resolve counter for stat event.\n");
 392                 return -EINVAL;
 393         }
 394
 395         *perf_counts(counter->counts, st->cpu, st->thread) = count;
 396         counter->supported = true;
 397         return 0;
 398 }
 399
 400 size_t perf_event__fprintf_stat(union perf_event *event, FILE *fp)
 401 {
 402         struct stat_event *st = (struct stat_event *) event;
 403         size_t ret;
 404
 405         ret  = fprintf(fp, "\n... id %" PRIu64 ", cpu %d, thread %d\n",
 406                        st->id, st->cpu, st->thread);
 407         ret += fprintf(fp, "... value %" PRIu64 ", enabled %" PRIu64 ", running %" PRIu64 "\n",
 408                        st->val, st->ena, st->run);
 409
 410         return ret;
 411 }
 412
 413 size_t perf_event__fprintf_stat_round(union perf_event *event, FILE *fp)
 414 {
 415         struct stat_round_event *rd = (struct stat_round_event *)event;
 416         size_t ret;
 417
 418         ret = fprintf(fp, "\n... time %" PRIu64 ", type %s\n", rd->time,
 419                       rd->type == PERF_STAT_ROUND_TYPE__FINAL ? "FINAL" : "INTERVAL");
 420
 421         return ret;
 422 }
 423
 424 size_t perf_event__fprintf_stat_config(union perf_event *event, FILE *fp)
 425 {
 426         struct perf_stat_config sc;
 427         size_t ret;
 428
 429         perf_event__read_stat_config(&sc, &event->stat_config);
 430
 431         ret  = fprintf(fp, "\n");
 432         ret += fprintf(fp, "... aggr_mode %d\n", sc.aggr_mode);
 433         ret += fprintf(fp, "... scale     %d\n", sc.scale);
 434         ret += fprintf(fp, "... interval  %u\n", sc.interval);
 435
 436         return ret;
 437 }