xref: /linux/tools/perf/util/stat.c (revision 78beef629fd95be4ed853b2d37b832f766bd96ca)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <inttypes.h>
4 #include <math.h>
5 #include <string.h>
6 #include "counts.h"
7 #include "debug.h"
8 #include "header.h"
9 #include "stat.h"
10 #include "session.h"
11 #include "target.h"
12 #include "evlist.h"
13 #include "evsel.h"
14 #include "thread_map.h"
15 #include <linux/zalloc.h>
16 
17 void update_stats(struct stats *stats, u64 val)
18 {
19 	double delta;
20 
21 	stats->n++;
22 	delta = val - stats->mean;
23 	stats->mean += delta / stats->n;
24 	stats->M2 += delta*(val - stats->mean);
25 
26 	if (val > stats->max)
27 		stats->max = val;
28 
29 	if (val < stats->min)
30 		stats->min = val;
31 }
32 
33 double avg_stats(struct stats *stats)
34 {
35 	return stats->mean;
36 }
37 
38 /*
39  * http://en.wikipedia.org/wiki/Algorithms_for_calculating_variance
40  *
41  *       (\Sum n_i^2) - ((\Sum n_i)^2)/n
42  * s^2 = -------------------------------
43  *                  n - 1
44  *
45  * http://en.wikipedia.org/wiki/Stddev
46  *
47  * The std dev of the mean is related to the std dev by:
48  *
49  *             s
50  * s_mean = -------
51  *          sqrt(n)
52  *
53  */
54 double stddev_stats(struct stats *stats)
55 {
56 	double variance, variance_mean;
57 
58 	if (stats->n < 2)
59 		return 0.0;
60 
61 	variance = stats->M2 / (stats->n - 1);
62 	variance_mean = variance / stats->n;
63 
64 	return sqrt(variance_mean);
65 }
66 
67 double rel_stddev_stats(double stddev, double avg)
68 {
69 	double pct = 0.0;
70 
71 	if (avg)
72 		pct = 100.0 * stddev/avg;
73 
74 	return pct;
75 }
76 
77 bool __perf_evsel_stat__is(struct evsel *evsel,
78 			   enum perf_stat_evsel_id id)
79 {
80 	struct perf_stat_evsel *ps = evsel->stats;
81 
82 	return ps->id == id;
83 }
84 
85 #define ID(id, name) [PERF_STAT_EVSEL_ID__##id] = #name
86 static const char *id_str[PERF_STAT_EVSEL_ID__MAX] = {
87 	ID(NONE,		x),
88 	ID(CYCLES_IN_TX,	cpu/cycles-t/),
89 	ID(TRANSACTION_START,	cpu/tx-start/),
90 	ID(ELISION_START,	cpu/el-start/),
91 	ID(CYCLES_IN_TX_CP,	cpu/cycles-ct/),
92 	ID(TOPDOWN_TOTAL_SLOTS, topdown-total-slots),
93 	ID(TOPDOWN_SLOTS_ISSUED, topdown-slots-issued),
94 	ID(TOPDOWN_SLOTS_RETIRED, topdown-slots-retired),
95 	ID(TOPDOWN_FETCH_BUBBLES, topdown-fetch-bubbles),
96 	ID(TOPDOWN_RECOVERY_BUBBLES, topdown-recovery-bubbles),
97 	ID(SMI_NUM, msr/smi/),
98 	ID(APERF, msr/aperf/),
99 };
100 #undef ID
101 
102 static void perf_stat_evsel_id_init(struct evsel *evsel)
103 {
104 	struct perf_stat_evsel *ps = evsel->stats;
105 	int i;
106 
107 	/* ps->id is 0 hence PERF_STAT_EVSEL_ID__NONE by default */
108 
109 	for (i = 0; i < PERF_STAT_EVSEL_ID__MAX; i++) {
110 		if (!strcmp(perf_evsel__name(evsel), id_str[i])) {
111 			ps->id = i;
112 			break;
113 		}
114 	}
115 }
116 
117 static void perf_evsel__reset_stat_priv(struct evsel *evsel)
118 {
119 	int i;
120 	struct perf_stat_evsel *ps = evsel->stats;
121 
122 	for (i = 0; i < 3; i++)
123 		init_stats(&ps->res_stats[i]);
124 
125 	perf_stat_evsel_id_init(evsel);
126 }
127 
128 static int perf_evsel__alloc_stat_priv(struct evsel *evsel)
129 {
130 	evsel->stats = zalloc(sizeof(struct perf_stat_evsel));
131 	if (evsel->stats == NULL)
132 		return -ENOMEM;
133 	perf_evsel__reset_stat_priv(evsel);
134 	return 0;
135 }
136 
137 static void perf_evsel__free_stat_priv(struct evsel *evsel)
138 {
139 	struct perf_stat_evsel *ps = evsel->stats;
140 
141 	if (ps)
142 		zfree(&ps->group_data);
143 	zfree(&evsel->stats);
144 }
145 
146 static int perf_evsel__alloc_prev_raw_counts(struct evsel *evsel,
147 					     int ncpus, int nthreads)
148 {
149 	struct perf_counts *counts;
150 
151 	counts = perf_counts__new(ncpus, nthreads);
152 	if (counts)
153 		evsel->prev_raw_counts = counts;
154 
155 	return counts ? 0 : -ENOMEM;
156 }
157 
158 static void perf_evsel__free_prev_raw_counts(struct evsel *evsel)
159 {
160 	perf_counts__delete(evsel->prev_raw_counts);
161 	evsel->prev_raw_counts = NULL;
162 }
163 
164 static int perf_evsel__alloc_stats(struct evsel *evsel, bool alloc_raw)
165 {
166 	int ncpus = perf_evsel__nr_cpus(evsel);
167 	int nthreads = perf_thread_map__nr(evsel->core.threads);
168 
169 	if (perf_evsel__alloc_stat_priv(evsel) < 0 ||
170 	    perf_evsel__alloc_counts(evsel, ncpus, nthreads) < 0 ||
171 	    (alloc_raw && perf_evsel__alloc_prev_raw_counts(evsel, ncpus, nthreads) < 0))
172 		return -ENOMEM;
173 
174 	return 0;
175 }
176 
177 int perf_evlist__alloc_stats(struct evlist *evlist, bool alloc_raw)
178 {
179 	struct evsel *evsel;
180 
181 	evlist__for_each_entry(evlist, evsel) {
182 		if (perf_evsel__alloc_stats(evsel, alloc_raw))
183 			goto out_free;
184 	}
185 
186 	return 0;
187 
188 out_free:
189 	perf_evlist__free_stats(evlist);
190 	return -1;
191 }
192 
193 void perf_evlist__free_stats(struct evlist *evlist)
194 {
195 	struct evsel *evsel;
196 
197 	evlist__for_each_entry(evlist, evsel) {
198 		perf_evsel__free_stat_priv(evsel);
199 		perf_evsel__free_counts(evsel);
200 		perf_evsel__free_prev_raw_counts(evsel);
201 	}
202 }
203 
204 void perf_evlist__reset_stats(struct evlist *evlist)
205 {
206 	struct evsel *evsel;
207 
208 	evlist__for_each_entry(evlist, evsel) {
209 		perf_evsel__reset_stat_priv(evsel);
210 		perf_evsel__reset_counts(evsel);
211 	}
212 }
213 
214 static void zero_per_pkg(struct evsel *counter)
215 {
216 	if (counter->per_pkg_mask)
217 		memset(counter->per_pkg_mask, 0, cpu__max_cpu());
218 }
219 
220 static int check_per_pkg(struct evsel *counter,
221 			 struct perf_counts_values *vals, int cpu, bool *skip)
222 {
223 	unsigned long *mask = counter->per_pkg_mask;
224 	struct perf_cpu_map *cpus = evsel__cpus(counter);
225 	int s;
226 
227 	*skip = false;
228 
229 	if (!counter->per_pkg)
230 		return 0;
231 
232 	if (perf_cpu_map__empty(cpus))
233 		return 0;
234 
235 	if (!mask) {
236 		mask = zalloc(cpu__max_cpu());
237 		if (!mask)
238 			return -ENOMEM;
239 
240 		counter->per_pkg_mask = mask;
241 	}
242 
243 	/*
244 	 * we do not consider an event that has not run as a good
245 	 * instance to mark a package as used (skip=1). Otherwise
246 	 * we may run into a situation where the first CPU in a package
247 	 * is not running anything, yet the second is, and this function
248 	 * would mark the package as used after the first CPU and would
249 	 * not read the values from the second CPU.
250 	 */
251 	if (!(vals->run && vals->ena))
252 		return 0;
253 
254 	s = cpu_map__get_socket(cpus, cpu, NULL);
255 	if (s < 0)
256 		return -1;
257 
258 	*skip = test_and_set_bit(s, mask) == 1;
259 	return 0;
260 }
261 
262 static int
263 process_counter_values(struct perf_stat_config *config, struct evsel *evsel,
264 		       int cpu, int thread,
265 		       struct perf_counts_values *count)
266 {
267 	struct perf_counts_values *aggr = &evsel->counts->aggr;
268 	static struct perf_counts_values zero;
269 	bool skip = false;
270 
271 	if (check_per_pkg(evsel, count, cpu, &skip)) {
272 		pr_err("failed to read per-pkg counter\n");
273 		return -1;
274 	}
275 
276 	if (skip)
277 		count = &zero;
278 
279 	switch (config->aggr_mode) {
280 	case AGGR_THREAD:
281 	case AGGR_CORE:
282 	case AGGR_DIE:
283 	case AGGR_SOCKET:
284 	case AGGR_NONE:
285 		if (!evsel->snapshot)
286 			perf_evsel__compute_deltas(evsel, cpu, thread, count);
287 		perf_counts_values__scale(count, config->scale, NULL);
288 		if ((config->aggr_mode == AGGR_NONE) && (!evsel->percore)) {
289 			perf_stat__update_shadow_stats(evsel, count->val,
290 						       cpu, &rt_stat);
291 		}
292 
293 		if (config->aggr_mode == AGGR_THREAD) {
294 			if (config->stats)
295 				perf_stat__update_shadow_stats(evsel,
296 					count->val, 0, &config->stats[thread]);
297 			else
298 				perf_stat__update_shadow_stats(evsel,
299 					count->val, 0, &rt_stat);
300 		}
301 		break;
302 	case AGGR_GLOBAL:
303 		aggr->val += count->val;
304 		aggr->ena += count->ena;
305 		aggr->run += count->run;
306 	case AGGR_UNSET:
307 	default:
308 		break;
309 	}
310 
311 	return 0;
312 }
313 
314 static int process_counter_maps(struct perf_stat_config *config,
315 				struct evsel *counter)
316 {
317 	int nthreads = perf_thread_map__nr(counter->core.threads);
318 	int ncpus = perf_evsel__nr_cpus(counter);
319 	int cpu, thread;
320 
321 	if (counter->system_wide)
322 		nthreads = 1;
323 
324 	for (thread = 0; thread < nthreads; thread++) {
325 		for (cpu = 0; cpu < ncpus; cpu++) {
326 			if (process_counter_values(config, counter, cpu, thread,
327 						   perf_counts(counter->counts, cpu, thread)))
328 				return -1;
329 		}
330 	}
331 
332 	return 0;
333 }
334 
335 int perf_stat_process_counter(struct perf_stat_config *config,
336 			      struct evsel *counter)
337 {
338 	struct perf_counts_values *aggr = &counter->counts->aggr;
339 	struct perf_stat_evsel *ps = counter->stats;
340 	u64 *count = counter->counts->aggr.values;
341 	int i, ret;
342 
343 	aggr->val = aggr->ena = aggr->run = 0;
344 
345 	/*
346 	 * We calculate counter's data every interval,
347 	 * and the display code shows ps->res_stats
348 	 * avg value. We need to zero the stats for
349 	 * interval mode, otherwise overall avg running
350 	 * averages will be shown for each interval.
351 	 */
352 	if (config->interval)
353 		init_stats(ps->res_stats);
354 
355 	if (counter->per_pkg)
356 		zero_per_pkg(counter);
357 
358 	ret = process_counter_maps(config, counter);
359 	if (ret)
360 		return ret;
361 
362 	if (config->aggr_mode != AGGR_GLOBAL)
363 		return 0;
364 
365 	if (!counter->snapshot)
366 		perf_evsel__compute_deltas(counter, -1, -1, aggr);
367 	perf_counts_values__scale(aggr, config->scale, &counter->counts->scaled);
368 
369 	for (i = 0; i < 3; i++)
370 		update_stats(&ps->res_stats[i], count[i]);
371 
372 	if (verbose > 0) {
373 		fprintf(config->output, "%s: %" PRIu64 " %" PRIu64 " %" PRIu64 "\n",
374 			perf_evsel__name(counter), count[0], count[1], count[2]);
375 	}
376 
377 	/*
378 	 * Save the full runtime - to allow normalization during printout:
379 	 */
380 	perf_stat__update_shadow_stats(counter, *count, 0, &rt_stat);
381 
382 	return 0;
383 }
384 
385 int perf_event__process_stat_event(struct perf_session *session,
386 				   union perf_event *event)
387 {
388 	struct perf_counts_values count;
389 	struct perf_record_stat *st = &event->stat;
390 	struct evsel *counter;
391 
392 	count.val = st->val;
393 	count.ena = st->ena;
394 	count.run = st->run;
395 
396 	counter = perf_evlist__id2evsel(session->evlist, st->id);
397 	if (!counter) {
398 		pr_err("Failed to resolve counter for stat event.\n");
399 		return -EINVAL;
400 	}
401 
402 	*perf_counts(counter->counts, st->cpu, st->thread) = count;
403 	counter->supported = true;
404 	return 0;
405 }
406 
407 size_t perf_event__fprintf_stat(union perf_event *event, FILE *fp)
408 {
409 	struct perf_record_stat *st = (struct perf_record_stat *)event;
410 	size_t ret;
411 
412 	ret  = fprintf(fp, "\n... id %" PRI_lu64 ", cpu %d, thread %d\n",
413 		       st->id, st->cpu, st->thread);
414 	ret += fprintf(fp, "... value %" PRI_lu64 ", enabled %" PRI_lu64 ", running %" PRI_lu64 "\n",
415 		       st->val, st->ena, st->run);
416 
417 	return ret;
418 }
419 
420 size_t perf_event__fprintf_stat_round(union perf_event *event, FILE *fp)
421 {
422 	struct perf_record_stat_round *rd = (struct perf_record_stat_round *)event;
423 	size_t ret;
424 
425 	ret = fprintf(fp, "\n... time %" PRI_lu64 ", type %s\n", rd->time,
426 		      rd->type == PERF_STAT_ROUND_TYPE__FINAL ? "FINAL" : "INTERVAL");
427 
428 	return ret;
429 }
430 
431 size_t perf_event__fprintf_stat_config(union perf_event *event, FILE *fp)
432 {
433 	struct perf_stat_config sc;
434 	size_t ret;
435 
436 	perf_event__read_stat_config(&sc, &event->stat_config);
437 
438 	ret  = fprintf(fp, "\n");
439 	ret += fprintf(fp, "... aggr_mode %d\n", sc.aggr_mode);
440 	ret += fprintf(fp, "... scale     %d\n", sc.scale);
441 	ret += fprintf(fp, "... interval  %u\n", sc.interval);
442 
443 	return ret;
444 }
445 
446 int create_perf_stat_counter(struct evsel *evsel,
447 			     struct perf_stat_config *config,
448 			     struct target *target)
449 {
450 	struct perf_event_attr *attr = &evsel->core.attr;
451 	struct evsel *leader = evsel->leader;
452 
453 	attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
454 			    PERF_FORMAT_TOTAL_TIME_RUNNING;
455 
456 	/*
457 	 * The event is part of non trivial group, let's enable
458 	 * the group read (for leader) and ID retrieval for all
459 	 * members.
460 	 */
461 	if (leader->core.nr_members > 1)
462 		attr->read_format |= PERF_FORMAT_ID|PERF_FORMAT_GROUP;
463 
464 	attr->inherit = !config->no_inherit;
465 
466 	/*
467 	 * Some events get initialized with sample_(period/type) set,
468 	 * like tracepoints. Clear it up for counting.
469 	 */
470 	attr->sample_period = 0;
471 
472 	if (config->identifier)
473 		attr->sample_type = PERF_SAMPLE_IDENTIFIER;
474 
475 	/*
476 	 * Disabling all counters initially, they will be enabled
477 	 * either manually by us or by kernel via enable_on_exec
478 	 * set later.
479 	 */
480 	if (perf_evsel__is_group_leader(evsel)) {
481 		attr->disabled = 1;
482 
483 		/*
484 		 * In case of initial_delay we enable tracee
485 		 * events manually.
486 		 */
487 		if (target__none(target) && !config->initial_delay)
488 			attr->enable_on_exec = 1;
489 	}
490 
491 	if (target__has_cpu(target) && !target__has_per_thread(target))
492 		return perf_evsel__open_per_cpu(evsel, evsel__cpus(evsel));
493 
494 	return perf_evsel__open_per_thread(evsel, evsel->core.threads);
495 }
496 
497 int perf_stat_synthesize_config(struct perf_stat_config *config,
498 				struct perf_tool *tool,
499 				struct evlist *evlist,
500 				perf_event__handler_t process,
501 				bool attrs)
502 {
503 	int err;
504 
505 	if (attrs) {
506 		err = perf_event__synthesize_attrs(tool, evlist, process);
507 		if (err < 0) {
508 			pr_err("Couldn't synthesize attrs.\n");
509 			return err;
510 		}
511 	}
512 
513 	err = perf_event__synthesize_extra_attr(tool, evlist, process,
514 						attrs);
515 
516 	err = perf_event__synthesize_thread_map2(tool, evlist->core.threads,
517 						 process, NULL);
518 	if (err < 0) {
519 		pr_err("Couldn't synthesize thread map.\n");
520 		return err;
521 	}
522 
523 	err = perf_event__synthesize_cpu_map(tool, evlist->core.cpus,
524 					     process, NULL);
525 	if (err < 0) {
526 		pr_err("Couldn't synthesize thread map.\n");
527 		return err;
528 	}
529 
530 	err = perf_event__synthesize_stat_config(tool, config, process, NULL);
531 	if (err < 0) {
532 		pr_err("Couldn't synthesize config.\n");
533 		return err;
534 	}
535 
536 	return 0;
537 }
538