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
spin_sleep(void)22 static int spin_sleep(void)
23 {
24 struct timeval start, now, diff, maxtime;
25 struct timespec ts;
26 int err, i;
27
28 maxtime.tv_sec = 0;
29 maxtime.tv_usec = 50000;
30
31 err = gettimeofday(&start, NULL);
32 if (err)
33 return err;
34
35 /* Spin for 50ms */
36 while (1) {
37 for (i = 0; i < 1000; i++)
38 barrier();
39
40 err = gettimeofday(&now, NULL);
41 if (err)
42 return err;
43
44 timersub(&now, &start, &diff);
45 if (timercmp(&diff, &maxtime, > /* For checkpatch */))
46 break;
47 }
48
49 ts.tv_nsec = 50 * 1000 * 1000;
50 ts.tv_sec = 0;
51
52 /* Sleep for 50ms */
53 err = nanosleep(&ts, NULL);
54 if (err == EINTR)
55 err = 0;
56
57 return err;
58 }
59
60 struct switch_tracking {
61 struct evsel *switch_evsel;
62 struct evsel *cycles_evsel;
63 pid_t *tids;
64 int nr_tids;
65 int comm_seen[4];
66 int cycles_before_comm_1;
67 int cycles_between_comm_2_and_comm_3;
68 int cycles_after_comm_4;
69 };
70
check_comm(struct switch_tracking * switch_tracking,union perf_event * event,const char * comm,int nr)71 static int check_comm(struct switch_tracking *switch_tracking,
72 union perf_event *event, const char *comm, int nr)
73 {
74 if (event->header.type == PERF_RECORD_COMM &&
75 (pid_t)event->comm.pid == getpid() &&
76 (pid_t)event->comm.tid == getpid() &&
77 strcmp(event->comm.comm, comm) == 0) {
78 if (switch_tracking->comm_seen[nr]) {
79 pr_debug("Duplicate comm event\n");
80 return -1;
81 }
82 switch_tracking->comm_seen[nr] = 1;
83 pr_debug3("comm event: %s nr: %d\n", event->comm.comm, nr);
84 return 1;
85 }
86 return 0;
87 }
88
check_cpu(struct switch_tracking * switch_tracking,int cpu)89 static int check_cpu(struct switch_tracking *switch_tracking, int cpu)
90 {
91 int i, nr = cpu + 1;
92
93 if (cpu < 0)
94 return -1;
95
96 if (!switch_tracking->tids) {
97 switch_tracking->tids = calloc(nr, sizeof(pid_t));
98 if (!switch_tracking->tids)
99 return -1;
100 for (i = 0; i < nr; i++)
101 switch_tracking->tids[i] = -1;
102 switch_tracking->nr_tids = nr;
103 return 0;
104 }
105
106 if (cpu >= switch_tracking->nr_tids) {
107 void *addr;
108
109 addr = realloc(switch_tracking->tids, nr * sizeof(pid_t));
110 if (!addr)
111 return -1;
112 switch_tracking->tids = addr;
113 for (i = switch_tracking->nr_tids; i < nr; i++)
114 switch_tracking->tids[i] = -1;
115 switch_tracking->nr_tids = nr;
116 return 0;
117 }
118
119 return 0;
120 }
121
process_sample_event(struct evlist * evlist,union perf_event * event,struct switch_tracking * switch_tracking)122 static int process_sample_event(struct evlist *evlist,
123 union perf_event *event,
124 struct switch_tracking *switch_tracking)
125 {
126 struct perf_sample sample;
127 struct evsel *evsel;
128 pid_t next_tid, prev_tid;
129 int cpu, err;
130
131 if (perf_evlist__parse_sample(evlist, event, &sample)) {
132 pr_debug("perf_evlist__parse_sample failed\n");
133 return -1;
134 }
135
136 evsel = perf_evlist__id2evsel(evlist, sample.id);
137 if (evsel == switch_tracking->switch_evsel) {
138 next_tid = evsel__intval(evsel, &sample, "next_pid");
139 prev_tid = evsel__intval(evsel, &sample, "prev_pid");
140 cpu = sample.cpu;
141 pr_debug3("sched_switch: cpu: %d prev_tid %d next_tid %d\n",
142 cpu, prev_tid, next_tid);
143 err = check_cpu(switch_tracking, cpu);
144 if (err)
145 return err;
146 /*
147 * Check for no missing sched_switch events i.e. that the
148 * evsel->core.system_wide flag has worked.
149 */
150 if (switch_tracking->tids[cpu] != -1 &&
151 switch_tracking->tids[cpu] != prev_tid) {
152 pr_debug("Missing sched_switch events\n");
153 return -1;
154 }
155 switch_tracking->tids[cpu] = next_tid;
156 }
157
158 if (evsel == switch_tracking->cycles_evsel) {
159 pr_debug3("cycles event\n");
160 if (!switch_tracking->comm_seen[0])
161 switch_tracking->cycles_before_comm_1 = 1;
162 if (switch_tracking->comm_seen[1] &&
163 !switch_tracking->comm_seen[2])
164 switch_tracking->cycles_between_comm_2_and_comm_3 = 1;
165 if (switch_tracking->comm_seen[3])
166 switch_tracking->cycles_after_comm_4 = 1;
167 }
168
169 return 0;
170 }
171
process_event(struct evlist * evlist,union perf_event * event,struct switch_tracking * switch_tracking)172 static int process_event(struct evlist *evlist, union perf_event *event,
173 struct switch_tracking *switch_tracking)
174 {
175 if (event->header.type == PERF_RECORD_SAMPLE)
176 return process_sample_event(evlist, event, switch_tracking);
177
178 if (event->header.type == PERF_RECORD_COMM) {
179 int err, done = 0;
180
181 err = check_comm(switch_tracking, event, "Test COMM 1", 0);
182 if (err < 0)
183 return -1;
184 done += err;
185 err = check_comm(switch_tracking, event, "Test COMM 2", 1);
186 if (err < 0)
187 return -1;
188 done += err;
189 err = check_comm(switch_tracking, event, "Test COMM 3", 2);
190 if (err < 0)
191 return -1;
192 done += err;
193 err = check_comm(switch_tracking, event, "Test COMM 4", 3);
194 if (err < 0)
195 return -1;
196 done += err;
197 if (done != 1) {
198 pr_debug("Unexpected comm event\n");
199 return -1;
200 }
201 }
202
203 return 0;
204 }
205
206 struct event_node {
207 struct list_head list;
208 union perf_event *event;
209 u64 event_time;
210 };
211
add_event(struct evlist * evlist,struct list_head * events,union perf_event * event)212 static int add_event(struct evlist *evlist, struct list_head *events,
213 union perf_event *event)
214 {
215 struct perf_sample sample;
216 struct event_node *node;
217
218 node = malloc(sizeof(struct event_node));
219 if (!node) {
220 pr_debug("malloc failed\n");
221 return -1;
222 }
223 node->event = event;
224 list_add(&node->list, events);
225
226 if (perf_evlist__parse_sample(evlist, event, &sample)) {
227 pr_debug("perf_evlist__parse_sample failed\n");
228 return -1;
229 }
230
231 if (!sample.time) {
232 pr_debug("event with no time\n");
233 return -1;
234 }
235
236 node->event_time = sample.time;
237
238 return 0;
239 }
240
free_event_nodes(struct list_head * events)241 static void free_event_nodes(struct list_head *events)
242 {
243 struct event_node *node;
244
245 while (!list_empty(events)) {
246 node = list_entry(events->next, struct event_node, list);
247 list_del_init(&node->list);
248 free(node);
249 }
250 }
251
compar(const void * a,const void * b)252 static int compar(const void *a, const void *b)
253 {
254 const struct event_node *nodea = a;
255 const struct event_node *nodeb = b;
256 s64 cmp = nodea->event_time - nodeb->event_time;
257
258 return cmp;
259 }
260
process_events(struct evlist * evlist,struct switch_tracking * switch_tracking)261 static int process_events(struct evlist *evlist,
262 struct switch_tracking *switch_tracking)
263 {
264 union perf_event *event;
265 unsigned pos, cnt = 0;
266 LIST_HEAD(events);
267 struct event_node *events_array, *node;
268 struct mmap *md;
269 int i, ret;
270
271 for (i = 0; i < evlist->core.nr_mmaps; i++) {
272 md = &evlist->mmap[i];
273 if (perf_mmap__read_init(&md->core) < 0)
274 continue;
275
276 while ((event = perf_mmap__read_event(&md->core)) != NULL) {
277 cnt += 1;
278 ret = add_event(evlist, &events, event);
279 perf_mmap__consume(&md->core);
280 if (ret < 0)
281 goto out_free_nodes;
282 }
283 perf_mmap__read_done(&md->core);
284 }
285
286 events_array = calloc(cnt, sizeof(struct event_node));
287 if (!events_array) {
288 pr_debug("calloc failed\n");
289 ret = -1;
290 goto out_free_nodes;
291 }
292
293 pos = 0;
294 list_for_each_entry(node, &events, list)
295 events_array[pos++] = *node;
296
297 qsort(events_array, cnt, sizeof(struct event_node), compar);
298
299 for (pos = 0; pos < cnt; pos++) {
300 ret = process_event(evlist, events_array[pos].event,
301 switch_tracking);
302 if (ret < 0)
303 goto out_free;
304 }
305
306 ret = 0;
307 out_free:
308 pr_debug("%u events recorded\n", cnt);
309 free(events_array);
310 out_free_nodes:
311 free_event_nodes(&events);
312 return ret;
313 }
314
315 /**
316 * test__switch_tracking - test using sched_switch and tracking events.
317 *
318 * This function implements a test that checks that sched_switch events and
319 * tracking events can be recorded for a workload (current process) using the
320 * evsel->core.system_wide and evsel->tracking flags (respectively) with other events
321 * sometimes enabled or disabled.
322 */
test__switch_tracking(struct test * test __maybe_unused,int subtest __maybe_unused)323 int test__switch_tracking(struct test *test __maybe_unused, int subtest __maybe_unused)
324 {
325 const char *sched_switch = "sched:sched_switch";
326 struct switch_tracking switch_tracking = { .tids = NULL, };
327 struct record_opts opts = {
328 .mmap_pages = UINT_MAX,
329 .user_freq = UINT_MAX,
330 .user_interval = ULLONG_MAX,
331 .freq = 4000,
332 .target = {
333 .uses_mmap = true,
334 },
335 };
336 struct perf_thread_map *threads = NULL;
337 struct perf_cpu_map *cpus = NULL;
338 struct evlist *evlist = NULL;
339 struct evsel *evsel, *cpu_clocks_evsel, *cycles_evsel;
340 struct evsel *switch_evsel, *tracking_evsel;
341 const char *comm;
342 int err = -1;
343
344 threads = thread_map__new(-1, getpid(), UINT_MAX);
345 if (!threads) {
346 pr_debug("thread_map__new failed!\n");
347 goto out_err;
348 }
349
350 cpus = perf_cpu_map__new(NULL);
351 if (!cpus) {
352 pr_debug("perf_cpu_map__new failed!\n");
353 goto out_err;
354 }
355
356 evlist = evlist__new();
357 if (!evlist) {
358 pr_debug("evlist__new failed!\n");
359 goto out_err;
360 }
361
362 perf_evlist__set_maps(&evlist->core, cpus, threads);
363
364 /* First event */
365 err = parse_events(evlist, "cpu-clock:u", NULL);
366 if (err) {
367 pr_debug("Failed to parse event dummy:u\n");
368 goto out_err;
369 }
370
371 cpu_clocks_evsel = evlist__last(evlist);
372
373 /* Second event */
374 err = parse_events(evlist, "cycles:u", NULL);
375 if (err) {
376 pr_debug("Failed to parse event cycles:u\n");
377 goto out_err;
378 }
379
380 cycles_evsel = evlist__last(evlist);
381
382 /* Third event */
383 if (!perf_evlist__can_select_event(evlist, sched_switch)) {
384 pr_debug("No sched_switch\n");
385 err = 0;
386 goto out;
387 }
388
389 err = parse_events(evlist, sched_switch, NULL);
390 if (err) {
391 pr_debug("Failed to parse event %s\n", sched_switch);
392 goto out_err;
393 }
394
395 switch_evsel = evlist__last(evlist);
396
397 evsel__set_sample_bit(switch_evsel, CPU);
398 evsel__set_sample_bit(switch_evsel, TIME);
399
400 switch_evsel->core.system_wide = true;
401 switch_evsel->no_aux_samples = true;
402 switch_evsel->immediate = true;
403
404 /* Test moving an event to the front */
405 if (cycles_evsel == evlist__first(evlist)) {
406 pr_debug("cycles event already at front");
407 goto out_err;
408 }
409 perf_evlist__to_front(evlist, cycles_evsel);
410 if (cycles_evsel != evlist__first(evlist)) {
411 pr_debug("Failed to move cycles event to front");
412 goto out_err;
413 }
414
415 evsel__set_sample_bit(cycles_evsel, CPU);
416 evsel__set_sample_bit(cycles_evsel, TIME);
417
418 /* Fourth event */
419 err = parse_events(evlist, "dummy:u", NULL);
420 if (err) {
421 pr_debug("Failed to parse event dummy:u\n");
422 goto out_err;
423 }
424
425 tracking_evsel = evlist__last(evlist);
426
427 perf_evlist__set_tracking_event(evlist, tracking_evsel);
428
429 tracking_evsel->core.attr.freq = 0;
430 tracking_evsel->core.attr.sample_period = 1;
431
432 evsel__set_sample_bit(tracking_evsel, TIME);
433
434 /* Config events */
435 perf_evlist__config(evlist, &opts, NULL);
436
437 /* Check moved event is still at the front */
438 if (cycles_evsel != evlist__first(evlist)) {
439 pr_debug("Front event no longer at front");
440 goto out_err;
441 }
442
443 /* Check tracking event is tracking */
444 if (!tracking_evsel->core.attr.mmap || !tracking_evsel->core.attr.comm) {
445 pr_debug("Tracking event not tracking\n");
446 goto out_err;
447 }
448
449 /* Check non-tracking events are not tracking */
450 evlist__for_each_entry(evlist, evsel) {
451 if (evsel != tracking_evsel) {
452 if (evsel->core.attr.mmap || evsel->core.attr.comm) {
453 pr_debug("Non-tracking event is tracking\n");
454 goto out_err;
455 }
456 }
457 }
458
459 if (evlist__open(evlist) < 0) {
460 pr_debug("Not supported\n");
461 err = 0;
462 goto out;
463 }
464
465 err = evlist__mmap(evlist, UINT_MAX);
466 if (err) {
467 pr_debug("evlist__mmap failed!\n");
468 goto out_err;
469 }
470
471 evlist__enable(evlist);
472
473 err = evsel__disable(cpu_clocks_evsel);
474 if (err) {
475 pr_debug("perf_evlist__disable_event failed!\n");
476 goto out_err;
477 }
478
479 err = spin_sleep();
480 if (err) {
481 pr_debug("spin_sleep failed!\n");
482 goto out_err;
483 }
484
485 comm = "Test COMM 1";
486 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0);
487 if (err) {
488 pr_debug("PR_SET_NAME failed!\n");
489 goto out_err;
490 }
491
492 err = evsel__disable(cycles_evsel);
493 if (err) {
494 pr_debug("perf_evlist__disable_event failed!\n");
495 goto out_err;
496 }
497
498 comm = "Test COMM 2";
499 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0);
500 if (err) {
501 pr_debug("PR_SET_NAME failed!\n");
502 goto out_err;
503 }
504
505 err = spin_sleep();
506 if (err) {
507 pr_debug("spin_sleep failed!\n");
508 goto out_err;
509 }
510
511 comm = "Test COMM 3";
512 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0);
513 if (err) {
514 pr_debug("PR_SET_NAME failed!\n");
515 goto out_err;
516 }
517
518 err = evsel__enable(cycles_evsel);
519 if (err) {
520 pr_debug("perf_evlist__disable_event failed!\n");
521 goto out_err;
522 }
523
524 comm = "Test COMM 4";
525 err = prctl(PR_SET_NAME, (unsigned long)comm, 0, 0, 0);
526 if (err) {
527 pr_debug("PR_SET_NAME failed!\n");
528 goto out_err;
529 }
530
531 err = spin_sleep();
532 if (err) {
533 pr_debug("spin_sleep failed!\n");
534 goto out_err;
535 }
536
537 evlist__disable(evlist);
538
539 switch_tracking.switch_evsel = switch_evsel;
540 switch_tracking.cycles_evsel = cycles_evsel;
541
542 err = process_events(evlist, &switch_tracking);
543
544 zfree(&switch_tracking.tids);
545
546 if (err)
547 goto out_err;
548
549 /* Check all 4 comm events were seen i.e. that evsel->tracking works */
550 if (!switch_tracking.comm_seen[0] || !switch_tracking.comm_seen[1] ||
551 !switch_tracking.comm_seen[2] || !switch_tracking.comm_seen[3]) {
552 pr_debug("Missing comm events\n");
553 goto out_err;
554 }
555
556 /* Check cycles event got enabled */
557 if (!switch_tracking.cycles_before_comm_1) {
558 pr_debug("Missing cycles events\n");
559 goto out_err;
560 }
561
562 /* Check cycles event got disabled */
563 if (switch_tracking.cycles_between_comm_2_and_comm_3) {
564 pr_debug("cycles events even though event was disabled\n");
565 goto out_err;
566 }
567
568 /* Check cycles event got enabled again */
569 if (!switch_tracking.cycles_after_comm_4) {
570 pr_debug("Missing cycles events\n");
571 goto out_err;
572 }
573 out:
574 if (evlist) {
575 evlist__disable(evlist);
576 evlist__delete(evlist);
577 } else {
578 perf_cpu_map__put(cpus);
579 perf_thread_map__put(threads);
580 }
581
582 return err;
583
584 out_err:
585 err = -1;
586 goto out;
587 }
588