xref: /openbmc/linux/tools/perf/util/stat.c (revision d8bcaabe) 
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 	ID(SMI_NUM, msr/smi/),
90 	ID(APERF, msr/aperf/),
91 };
92 #undef ID
93 
94 void perf_stat_evsel_id_init(struct perf_evsel *evsel)
95 {
96 	struct perf_stat_evsel *ps = evsel->priv;
97 	int i;
98 
99 	/* ps->id is 0 hence PERF_STAT_EVSEL_ID__NONE by default */
100 
101 	for (i = 0; i < PERF_STAT_EVSEL_ID__MAX; i++) {
102 		if (!strcmp(perf_evsel__name(evsel), id_str[i])) {
103 			ps->id = i;
104 			break;
105 		}
106 	}
107 }
108 
109 static void perf_evsel__reset_stat_priv(struct perf_evsel *evsel)
110 {
111 	int i;
112 	struct perf_stat_evsel *ps = evsel->priv;
113 
114 	for (i = 0; i < 3; i++)
115 		init_stats(&ps->res_stats[i]);
116 
117 	perf_stat_evsel_id_init(evsel);
118 }
119 
120 static int perf_evsel__alloc_stat_priv(struct perf_evsel *evsel)
121 {
122 	evsel->priv = zalloc(sizeof(struct perf_stat_evsel));
123 	if (evsel->priv == NULL)
124 		return -ENOMEM;
125 	perf_evsel__reset_stat_priv(evsel);
126 	return 0;
127 }
128 
129 static void perf_evsel__free_stat_priv(struct perf_evsel *evsel)
130 {
131 	struct perf_stat_evsel *ps = evsel->priv;
132 
133 	if (ps)
134 		free(ps->group_data);
135 	zfree(&evsel->priv);
136 }
137 
138 static int perf_evsel__alloc_prev_raw_counts(struct perf_evsel *evsel,
139 					     int ncpus, int nthreads)
140 {
141 	struct perf_counts *counts;
142 
143 	counts = perf_counts__new(ncpus, nthreads);
144 	if (counts)
145 		evsel->prev_raw_counts = counts;
146 
147 	return counts ? 0 : -ENOMEM;
148 }
149 
150 static void perf_evsel__free_prev_raw_counts(struct perf_evsel *evsel)
151 {
152 	perf_counts__delete(evsel->prev_raw_counts);
153 	evsel->prev_raw_counts = NULL;
154 }
155 
156 static int perf_evsel__alloc_stats(struct perf_evsel *evsel, bool alloc_raw)
157 {
158 	int ncpus = perf_evsel__nr_cpus(evsel);
159 	int nthreads = thread_map__nr(evsel->threads);
160 
161 	if (perf_evsel__alloc_stat_priv(evsel) < 0 ||
162 	    perf_evsel__alloc_counts(evsel, ncpus, nthreads) < 0 ||
163 	    (alloc_raw && perf_evsel__alloc_prev_raw_counts(evsel, ncpus, nthreads) < 0))
164 		return -ENOMEM;
165 
166 	return 0;
167 }
168 
169 int perf_evlist__alloc_stats(struct perf_evlist *evlist, bool alloc_raw)
170 {
171 	struct perf_evsel *evsel;
172 
173 	evlist__for_each_entry(evlist, evsel) {
174 		if (perf_evsel__alloc_stats(evsel, alloc_raw))
175 			goto out_free;
176 	}
177 
178 	return 0;
179 
180 out_free:
181 	perf_evlist__free_stats(evlist);
182 	return -1;
183 }
184 
185 void perf_evlist__free_stats(struct perf_evlist *evlist)
186 {
187 	struct perf_evsel *evsel;
188 
189 	evlist__for_each_entry(evlist, evsel) {
190 		perf_evsel__free_stat_priv(evsel);
191 		perf_evsel__free_counts(evsel);
192 		perf_evsel__free_prev_raw_counts(evsel);
193 	}
194 }
195 
196 void perf_evlist__reset_stats(struct perf_evlist *evlist)
197 {
198 	struct perf_evsel *evsel;
199 
200 	evlist__for_each_entry(evlist, evsel) {
201 		perf_evsel__reset_stat_priv(evsel);
202 		perf_evsel__reset_counts(evsel);
203 	}
204 }
205 
206 static void zero_per_pkg(struct perf_evsel *counter)
207 {
208 	if (counter->per_pkg_mask)
209 		memset(counter->per_pkg_mask, 0, MAX_NR_CPUS);
210 }
211 
212 static int check_per_pkg(struct perf_evsel *counter,
213 			 struct perf_counts_values *vals, int cpu, bool *skip)
214 {
215 	unsigned long *mask = counter->per_pkg_mask;
216 	struct cpu_map *cpus = perf_evsel__cpus(counter);
217 	int s;
218 
219 	*skip = false;
220 
221 	if (!counter->per_pkg)
222 		return 0;
223 
224 	if (cpu_map__empty(cpus))
225 		return 0;
226 
227 	if (!mask) {
228 		mask = zalloc(MAX_NR_CPUS);
229 		if (!mask)
230 			return -ENOMEM;
231 
232 		counter->per_pkg_mask = mask;
233 	}
234 
235 	/*
236 	 * we do not consider an event that has not run as a good
237 	 * instance to mark a package as used (skip=1). Otherwise
238 	 * we may run into a situation where the first CPU in a package
239 	 * is not running anything, yet the second is, and this function
240 	 * would mark the package as used after the first CPU and would
241 	 * not read the values from the second CPU.
242 	 */
243 	if (!(vals->run && vals->ena))
244 		return 0;
245 
246 	s = cpu_map__get_socket(cpus, cpu, NULL);
247 	if (s < 0)
248 		return -1;
249 
250 	*skip = test_and_set_bit(s, mask) == 1;
251 	return 0;
252 }
253 
254 static int
255 process_counter_values(struct perf_stat_config *config, struct perf_evsel *evsel,
256 		       int cpu, int thread,
257 		       struct perf_counts_values *count)
258 {
259 	struct perf_counts_values *aggr = &evsel->counts->aggr;
260 	static struct perf_counts_values zero;
261 	bool skip = false;
262 
263 	if (check_per_pkg(evsel, count, cpu, &skip)) {
264 		pr_err("failed to read per-pkg counter\n");
265 		return -1;
266 	}
267 
268 	if (skip)
269 		count = &zero;
270 
271 	switch (config->aggr_mode) {
272 	case AGGR_THREAD:
273 	case AGGR_CORE:
274 	case AGGR_SOCKET:
275 	case AGGR_NONE:
276 		if (!evsel->snapshot)
277 			perf_evsel__compute_deltas(evsel, cpu, thread, count);
278 		perf_counts_values__scale(count, config->scale, NULL);
279 		if (config->aggr_mode == AGGR_NONE)
280 			perf_stat__update_shadow_stats(evsel, count->values, cpu);
281 		break;
282 	case AGGR_GLOBAL:
283 		aggr->val += count->val;
284 		if (config->scale) {
285 			aggr->ena += count->ena;
286 			aggr->run += count->run;
287 		}
288 	case AGGR_UNSET:
289 	default:
290 		break;
291 	}
292 
293 	return 0;
294 }
295 
296 static int process_counter_maps(struct perf_stat_config *config,
297 				struct perf_evsel *counter)
298 {
299 	int nthreads = thread_map__nr(counter->threads);
300 	int ncpus = perf_evsel__nr_cpus(counter);
301 	int cpu, thread;
302 
303 	if (counter->system_wide)
304 		nthreads = 1;
305 
306 	for (thread = 0; thread < nthreads; thread++) {
307 		for (cpu = 0; cpu < ncpus; cpu++) {
308 			if (process_counter_values(config, counter, cpu, thread,
309 						   perf_counts(counter->counts, cpu, thread)))
310 				return -1;
311 		}
312 	}
313 
314 	return 0;
315 }
316 
317 int perf_stat_process_counter(struct perf_stat_config *config,
318 			      struct perf_evsel *counter)
319 {
320 	struct perf_counts_values *aggr = &counter->counts->aggr;
321 	struct perf_stat_evsel *ps = counter->priv;
322 	u64 *count = counter->counts->aggr.values;
323 	u64 val;
324 	int i, ret;
325 
326 	aggr->val = aggr->ena = aggr->run = 0;
327 
328 	/*
329 	 * We calculate counter's data every interval,
330 	 * and the display code shows ps->res_stats
331 	 * avg value. We need to zero the stats for
332 	 * interval mode, otherwise overall avg running
333 	 * averages will be shown for each interval.
334 	 */
335 	if (config->interval)
336 		init_stats(ps->res_stats);
337 
338 	if (counter->per_pkg)
339 		zero_per_pkg(counter);
340 
341 	ret = process_counter_maps(config, counter);
342 	if (ret)
343 		return ret;
344 
345 	if (config->aggr_mode != AGGR_GLOBAL)
346 		return 0;
347 
348 	if (!counter->snapshot)
349 		perf_evsel__compute_deltas(counter, -1, -1, aggr);
350 	perf_counts_values__scale(aggr, config->scale, &counter->counts->scaled);
351 
352 	for (i = 0; i < 3; i++)
353 		update_stats(&ps->res_stats[i], count[i]);
354 
355 	if (verbose > 0) {
356 		fprintf(config->output, "%s: %" PRIu64 " %" PRIu64 " %" PRIu64 "\n",
357 			perf_evsel__name(counter), count[0], count[1], count[2]);
358 	}
359 
360 	/*
361 	 * Save the full runtime - to allow normalization during printout:
362 	 */
363 	val = counter->scale * *count;
364 	perf_stat__update_shadow_stats(counter, &val, 0);
365 
366 	return 0;
367 }
368 
369 int perf_event__process_stat_event(struct perf_tool *tool __maybe_unused,
370 				   union perf_event *event,
371 				   struct perf_session *session)
372 {
373 	struct perf_counts_values count;
374 	struct stat_event *st = &event->stat;
375 	struct perf_evsel *counter;
376 
377 	count.val = st->val;
378 	count.ena = st->ena;
379 	count.run = st->run;
380 
381 	counter = perf_evlist__id2evsel(session->evlist, st->id);
382 	if (!counter) {
383 		pr_err("Failed to resolve counter for stat event.\n");
384 		return -EINVAL;
385 	}
386 
387 	*perf_counts(counter->counts, st->cpu, st->thread) = count;
388 	counter->supported = true;
389 	return 0;
390 }
391 
392 size_t perf_event__fprintf_stat(union perf_event *event, FILE *fp)
393 {
394 	struct stat_event *st = (struct stat_event *) event;
395 	size_t ret;
396 
397 	ret  = fprintf(fp, "\n... id %" PRIu64 ", cpu %d, thread %d\n",
398 		       st->id, st->cpu, st->thread);
399 	ret += fprintf(fp, "... value %" PRIu64 ", enabled %" PRIu64 ", running %" PRIu64 "\n",
400 		       st->val, st->ena, st->run);
401 
402 	return ret;
403 }
404 
405 size_t perf_event__fprintf_stat_round(union perf_event *event, FILE *fp)
406 {
407 	struct stat_round_event *rd = (struct stat_round_event *)event;
408 	size_t ret;
409 
410 	ret = fprintf(fp, "\n... time %" PRIu64 ", type %s\n", rd->time,
411 		      rd->type == PERF_STAT_ROUND_TYPE__FINAL ? "FINAL" : "INTERVAL");
412 
413 	return ret;
414 }
415 
416 size_t perf_event__fprintf_stat_config(union perf_event *event, FILE *fp)
417 {
418 	struct perf_stat_config sc;
419 	size_t ret;
420 
421 	perf_event__read_stat_config(&sc, &event->stat_config);
422 
423 	ret  = fprintf(fp, "\n");
424 	ret += fprintf(fp, "... aggr_mode %d\n", sc.aggr_mode);
425 	ret += fprintf(fp, "... scale     %d\n", sc.scale);
426 	ret += fprintf(fp, "... interval  %u\n", sc.interval);
427 
428 	return ret;
429 }
430