1 // SPDX-License-Identifier: GPL-2.0
2 #include <sys/time.h>
3 #include <sys/prctl.h>
4 #include <errno.h>
5 #include <limits.h>
6 #include <time.h>
7 #include <stdlib.h>
8 #include <linux/zalloc.h>
9 #include <perf/cpumap.h>
10 #include <perf/evlist.h>
11 #include <perf/mmap.h>
12
13 #include "debug.h"
14 #include "parse-events.h"
15 #include "evlist.h"
16 #include "evsel.h"
17 #include "thread_map.h"
18 #include "record.h"
19 #include "tests.h"
20 #include "util/mmap.h"
21 #include "pmu.h"
22
spin_sleep(void)23 static int spin_sleep(void)
24 {
25 struct timeval start, now, diff, maxtime;
26 struct timespec ts;
27 int err, i;
28
29 maxtime.tv_sec = 0;
30 maxtime.tv_usec = 50000;
31
32 err = gettimeofday(&start, NULL);
33 if (err)
34 return err;
35
36 /* Spin for 50ms */
37 while (1) {
38 for (i = 0; i < 1000; i++)
39 barrier();
40
41 err = gettimeofday(&now, NULL);
42 if (err)
43 return err;
44
45 timersub(&now, &start, &diff);
46 if (timercmp(&diff, &maxtime, > /* For checkpatch */))
47 break;
48 }
49
50 ts.tv_nsec = 50 * 1000 * 1000;
51 ts.tv_sec = 0;
52
53 /* Sleep for 50ms */
54 err = nanosleep(&ts, NULL);
55 if (err == EINTR)
56 err = 0;
57
58 return err;
59 }
60
61 struct switch_tracking {
62 struct evsel *switch_evsel;
63 struct evsel *cycles_evsel;
64 pid_t *tids;
65 int nr_tids;
66 int comm_seen[4];
67 int cycles_before_comm_1;
68 int cycles_between_comm_2_and_comm_3;
69 int cycles_after_comm_4;
70 };
71
check_comm(struct switch_tracking * switch_tracking,union perf_event * event,const char * comm,int nr)72 static int check_comm(struct switch_tracking *switch_tracking,
73 union perf_event *event, const char *comm, int nr)
74 {
75 if (event->header.type == PERF_RECORD_COMM &&
76 (pid_t)event->comm.pid == getpid() &&
77 (pid_t)event->comm.tid == getpid() &&
78 strcmp(event->comm.comm, comm) == 0) {
79 if (switch_tracking->comm_seen[nr]) {
80 pr_debug("Duplicate comm event\n");
81 return -1;
82 }
83 switch_tracking->comm_seen[nr] = 1;
84 pr_debug3("comm event: %s nr: %d\n", event->comm.comm, nr);
85 return 1;
86 }
87 return 0;
88 }
89
check_cpu(struct switch_tracking * switch_tracking,int cpu)90 static int check_cpu(struct switch_tracking *switch_tracking, int cpu)
91 {
92 int i, nr = cpu + 1;
93
94 if (cpu < 0)
95 return -1;
96
97 if (!switch_tracking->tids) {
98 switch_tracking->tids = calloc(nr, sizeof(pid_t));
99 if (!switch_tracking->tids)
100 return -1;
101 for (i = 0; i < nr; i++)
102 switch_tracking->tids[i] = -1;
103 switch_tracking->nr_tids = nr;
104 return 0;
105 }
106
107 if (cpu >= switch_tracking->nr_tids) {
108 void *addr;
109
110 addr = realloc(switch_tracking->tids, nr * sizeof(pid_t));
111 if (!addr)
112 return -1;
113 switch_tracking->tids = addr;
114 for (i = switch_tracking->nr_tids; i < nr; i++)
115 switch_tracking->tids[i] = -1;
116 switch_tracking->nr_tids = nr;
117 return 0;
118 }
119
120 return 0;
121 }
122
process_sample_event(struct evlist * evlist,union perf_event * event,struct switch_tracking * switch_tracking)123 static int process_sample_event(struct evlist *evlist,
124 union perf_event *event,
125 struct switch_tracking *switch_tracking)
126 {
127 struct perf_sample sample;
128 struct evsel *evsel;
129 pid_t next_tid, prev_tid;
130 int cpu, err;
131
132 if (evlist__parse_sample(evlist, event, &sample)) {
133 pr_debug("evlist__parse_sample failed\n");
134 return -1;
135 }
136
137 evsel = evlist__id2evsel(evlist, sample.id);
138 if (evsel == switch_tracking->switch_evsel) {
139 next_tid = evsel__intval(evsel, &sample, "next_pid");
140 prev_tid = evsel__intval(evsel, &sample, "prev_pid");
141 cpu = sample.cpu;
142 pr_debug3("sched_switch: cpu: %d prev_tid %d next_tid %d\n",
143 cpu, prev_tid, next_tid);
144 err = check_cpu(switch_tracking, cpu);
145 if (err)
146 return err;
147 /*
148 * Check for no missing sched_switch events i.e. that the
149 * evsel->core.system_wide flag has worked.
150 */
151 if (switch_tracking->tids[cpu] != -1 &&
152 switch_tracking->tids[cpu] != prev_tid) {
153 pr_debug("Missing sched_switch events\n");
154 return -1;
155 }
156 switch_tracking->tids[cpu] = next_tid;
157 }
158
159 if (evsel == switch_tracking->cycles_evsel) {
160 pr_debug3("cycles event\n");
161 if (!switch_tracking->comm_seen[0])
162 switch_tracking->cycles_before_comm_1 = 1;
163 if (switch_tracking->comm_seen[1] &&
164 !switch_tracking->comm_seen[2])
165 switch_tracking->cycles_between_comm_2_and_comm_3 = 1;
166 if (switch_tracking->comm_seen[3])
167 switch_tracking->cycles_after_comm_4 = 1;
168 }
169
170 return 0;
171 }
172
process_event(struct evlist * evlist,union perf_event * event,struct switch_tracking * switch_tracking)173 static int process_event(struct evlist *evlist, union perf_event *event,
174 struct switch_tracking *switch_tracking)
175 {
176 if (event->header.type == PERF_RECORD_SAMPLE)
177 return process_sample_event(evlist, event, switch_tracking);
178
179 if (event->header.type == PERF_RECORD_COMM) {
180 int err, done = 0;
181
182 err = check_comm(switch_tracking, event, "Test COMM 1", 0);
183 if (err < 0)
184 return -1;
185 done += err;
186 err = check_comm(switch_tracking, event, "Test COMM 2", 1);
187 if (err < 0)
188 return -1;
189 done += err;
190 err = check_comm(switch_tracking, event, "Test COMM 3", 2);
191 if (err < 0)
192 return -1;
193 done += err;
194 err = check_comm(switch_tracking, event, "Test COMM 4", 3);
195 if (err < 0)
196 return -1;
197 done += err;
198 if (done != 1) {
199 pr_debug("Unexpected comm event\n");
200 return -1;
201 }
202 }
203
204 return 0;
205 }
206
207 struct event_node {
208 struct list_head list;
209 union perf_event *event;
210 u64 event_time;
211 };
212
add_event(struct evlist * evlist,struct list_head * events,union perf_event * event)213 static int add_event(struct evlist *evlist, struct list_head *events,
214 union perf_event *event)
215 {
216 struct perf_sample sample;
217 struct event_node *node;
218
219 node = malloc(sizeof(struct event_node));
220 if (!node) {
221 pr_debug("malloc failed\n");
222 return -1;
223 }
224 node->event = event;
225 list_add(&node->list, events);
226
227 if (evlist__parse_sample(evlist, event, &sample)) {
228 pr_debug("evlist__parse_sample failed\n");
229 return -1;
230 }
231
232 if (!sample.time) {
233 pr_debug("event with no time\n");
234 return -1;
235 }
236
237 node->event_time = sample.time;
238
239 return 0;
240 }
241
free_event_nodes(struct list_head * events)242 static void free_event_nodes(struct list_head *events)
243 {
244 struct event_node *node;
245
246 while (!list_empty(events)) {
247 node = list_entry(events->next, struct event_node, list);
248 list_del_init(&node->list);
249 free(node);
250 }
251 }
252
compar(const void * a,const void * b)253 static int compar(const void *a, const void *b)
254 {
255 const struct event_node *nodea = a;
256 const struct event_node *nodeb = b;
257 s64 cmp = nodea->event_time - nodeb->event_time;
258
259 return cmp;
260 }
261
process_events(struct evlist * evlist,struct switch_tracking * switch_tracking)262 static int process_events(struct evlist *evlist,
263 struct switch_tracking *switch_tracking)
264 {
265 union perf_event *event;
266 unsigned pos, cnt = 0;
267 LIST_HEAD(events);
268 struct event_node *events_array, *node;
269 struct mmap *md;
270 int i, ret;
271
272 for (i = 0; i < evlist->core.nr_mmaps; i++) {
273 md = &evlist->mmap[i];
274 if (perf_mmap__read_init(&md->core) < 0)
275 continue;
276
277 while ((event = perf_mmap__read_event(&md->core)) != NULL) {
278 cnt += 1;
279 ret = add_event(evlist, &events, event);
280 perf_mmap__consume(&md->core);
281 if (ret < 0)
282 goto out_free_nodes;
283 }
284 perf_mmap__read_done(&md->core);
285 }
286
287 events_array = calloc(cnt, sizeof(struct event_node));
288 if (!events_array) {
289 pr_debug("calloc failed\n");
290 ret = -1;
291 goto out_free_nodes;
292 }
293
294 pos = 0;
295 list_for_each_entry(node, &events, list)
296 events_array[pos++] = *node;
297
298 qsort(events_array, cnt, sizeof(struct event_node), compar);
299
300 for (pos = 0; pos < cnt; pos++) {
301 ret = process_event(evlist, events_array[pos].event,
302 switch_tracking);
303 if (ret < 0)
304 goto out_free;
305 }
306
307 ret = 0;
308 out_free:
309 pr_debug("%u events recorded\n", cnt);
310 free(events_array);
311 out_free_nodes:
312 free_event_nodes(&events);
313 return ret;
314 }
315
316 /**
317 * test__switch_tracking - test using sched_switch and tracking events.
318 *
319 * This function implements a test that checks that sched_switch events and
320 * tracking events can be recorded for a workload (current process) using the
321 * evsel->core.system_wide and evsel->tracking flags (respectively) with other events
322 * sometimes enabled or disabled.
323 */
test__switch_tracking(struct test * test __maybe_unused,int subtest __maybe_unused)324 int test__switch_tracking(struct test *test __maybe_unused, int subtest __maybe_unused)
325 {
326 const char *sched_switch = "sched:sched_switch";
327 struct switch_tracking switch_tracking = { .tids = NULL, };
328 struct record_opts opts = {
329 .mmap_pages = UINT_MAX,
330 .user_freq = UINT_MAX,
331 .user_interval = ULLONG_MAX,
332 .freq = 4000,
333 .target = {
334 .uses_mmap = true,
335 },
336 };
337 struct perf_thread_map *threads = NULL;
338 struct perf_cpu_map *cpus = NULL;
339 struct evlist *evlist = NULL;
340 struct evsel *evsel, *cpu_clocks_evsel, *cycles_evsel;
341 struct evsel *switch_evsel, *tracking_evsel;
342 const char *comm;
343 int err = -1;
344
345 threads = thread_map__new(-1, getpid(), UINT_MAX);
346 if (!threads) {
347 pr_debug("thread_map__new failed!\n");
348 goto out_err;
349 }
350
351 cpus = perf_cpu_map__new(NULL);
352 if (!cpus) {
353 pr_debug("perf_cpu_map__new failed!\n");
354 goto out_err;
355 }
356
357 evlist = evlist__new();
358 if (!evlist) {
359 pr_debug("evlist__new failed!\n");
360 goto out_err;
361 }
362
363 perf_evlist__set_maps(&evlist->core, cpus, threads);
364
365 /* First event */
366 err = parse_events(evlist, "cpu-clock:u", NULL);
367 if (err) {
368 pr_debug("Failed to parse event dummy:u\n");
369 goto out_err;
370 }
371
372 cpu_clocks_evsel = evlist__last(evlist);
373
374 /* Second event */
375 if (perf_pmu__has_hybrid())
376 err = parse_events(evlist, "cpu_core/cycles/u", NULL);
377 else
378 err = parse_events(evlist, "cycles:u", NULL);
379 if (err) {
380 pr_debug("Failed to parse event cycles:u\n");
381 goto out_err;
382 }
383
384 cycles_evsel = evlist__last(evlist);
385
386 /* Third event */
387 if (!evlist__can_select_event(evlist, sched_switch)) {
388 pr_debug("No sched_switch\n");
389 err = 0;
390 goto out;
391 }
392
393 err = parse_events(evlist, sched_switch, NULL);
394 if (err) {
395 pr_debug("Failed to parse event %s\n", sched_switch);
396 goto out_err;
397 }
398
399 switch_evsel = evlist__last(evlist);
400
401 evsel__set_sample_bit(switch_evsel, CPU);
402 evsel__set_sample_bit(switch_evsel, TIME);
403
404 switch_evsel->core.system_wide = true;
405 switch_evsel->no_aux_samples = true;
406 switch_evsel->immediate = true;
407
408 /* Test moving an event to the front */
409 if (cycles_evsel == evlist__first(evlist)) {
410 pr_debug("cycles event already at front");
411 goto out_err;
412 }
413 evlist__to_front(evlist, cycles_evsel);
414 if (cycles_evsel != evlist__first(evlist)) {
415 pr_debug("Failed to move cycles event to front");
416 goto out_err;
417 }
418
419 evsel__set_sample_bit(cycles_evsel, CPU);
420 evsel__set_sample_bit(cycles_evsel, TIME);
421
422 /* Fourth event */
423 err = parse_events(evlist, "dummy:u", NULL);
424 if (err) {
425 pr_debug("Failed to parse event dummy:u\n");
426 goto out_err;
427 }
428
429 tracking_evsel = evlist__last(evlist);
430
431 evlist__set_tracking_event(evlist, tracking_evsel);
432
433 tracking_evsel->core.attr.freq = 0;
434 tracking_evsel->core.attr.sample_period = 1;
435
436 evsel__set_sample_bit(tracking_evsel, TIME);
437
438 /* Config events */
439 evlist__config(evlist, &opts, NULL);
440
441 /* Check moved event is still at the front */
442 if (cycles_evsel != evlist__first(evlist)) {
443 pr_debug("Front event no longer at front");
444 goto out_err;
445 }
446
447 /* Check tracking event is tracking */
448 if (!tracking_evsel->core.attr.mmap || !tracking_evsel->core.attr.comm) {
449 pr_debug("Tracking event not tracking\n");
450 goto out_err;
451 }
452
453 /* Check non-tracking events are not tracking */
454 evlist__for_each_entry(evlist, evsel) {
455 if (evsel != tracking_evsel) {
456 if (evsel->core.attr.mmap || evsel->core.attr.comm) {
457 pr_debug("Non-tracking event is tracking\n");
458 goto out_err;
459 }
460 }
461 }
462
463 if (evlist__open(evlist) < 0) {
464 pr_debug("Not supported\n");
465 err = 0;
466 goto out;
467 }
468
469 err = evlist__mmap(evlist, UINT_MAX);
470 if (err) {
471 pr_debug("evlist__mmap failed!\n");
472 goto out_err;
473 }
474
475 evlist__enable(evlist);
476
477 err = evsel__disable(cpu_clocks_evsel);
478 if (err) {
479 pr_debug("perf_evlist__disable_event failed!\n");
480 goto out_err;
481 }
482
483 err = spin_sleep();
484 if (err) {
485 pr_debug("spin_sleep failed!\n");
486 goto out_err;
487 }
488
489 comm = "Test COMM 1";
490 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0);
491 if (err) {
492 pr_debug("PR_SET_NAME failed!\n");
493 goto out_err;
494 }
495
496 err = evsel__disable(cycles_evsel);
497 if (err) {
498 pr_debug("perf_evlist__disable_event failed!\n");
499 goto out_err;
500 }
501
502 comm = "Test COMM 2";
503 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0);
504 if (err) {
505 pr_debug("PR_SET_NAME failed!\n");
506 goto out_err;
507 }
508
509 err = spin_sleep();
510 if (err) {
511 pr_debug("spin_sleep failed!\n");
512 goto out_err;
513 }
514
515 comm = "Test COMM 3";
516 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0);
517 if (err) {
518 pr_debug("PR_SET_NAME failed!\n");
519 goto out_err;
520 }
521
522 err = evsel__enable(cycles_evsel);
523 if (err) {
524 pr_debug("perf_evlist__disable_event failed!\n");
525 goto out_err;
526 }
527
528 comm = "Test COMM 4";
529 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0);
530 if (err) {
531 pr_debug("PR_SET_NAME failed!\n");
532 goto out_err;
533 }
534
535 err = spin_sleep();
536 if (err) {
537 pr_debug("spin_sleep failed!\n");
538 goto out_err;
539 }
540
541 evlist__disable(evlist);
542
543 switch_tracking.switch_evsel = switch_evsel;
544 switch_tracking.cycles_evsel = cycles_evsel;
545
546 err = process_events(evlist, &switch_tracking);
547
548 zfree(&switch_tracking.tids);
549
550 if (err)
551 goto out_err;
552
553 /* Check all 4 comm events were seen i.e. that evsel->tracking works */
554 if (!switch_tracking.comm_seen[0] || !switch_tracking.comm_seen[1] ||
555 !switch_tracking.comm_seen[2] || !switch_tracking.comm_seen[3]) {
556 pr_debug("Missing comm events\n");
557 goto out_err;
558 }
559
560 /* Check cycles event got enabled */
561 if (!switch_tracking.cycles_before_comm_1) {
562 pr_debug("Missing cycles events\n");
563 goto out_err;
564 }
565
566 /* Check cycles event got disabled */
567 if (switch_tracking.cycles_between_comm_2_and_comm_3) {
568 pr_debug("cycles events even though event was disabled\n");
569 goto out_err;
570 }
571
572 /* Check cycles event got enabled again */
573 if (!switch_tracking.cycles_after_comm_4) {
574 pr_debug("Missing cycles events\n");
575 goto out_err;
576 }
577 out:
578 if (evlist) {
579 evlist__disable(evlist);
580 evlist__delete(evlist);
581 }
582 perf_cpu_map__put(cpus);
583 perf_thread_map__put(threads);
584
585 return err;
586
587 out_err:
588 err = -1;
589 goto out;
590 }
591