xref: /openbmc/linux/tools/perf/util/stat.c (revision f7d84fa7)
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 }
424