1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
|
// SPDX-License-Identifier: GPL-2.0
#include <subcmd/parse-options.h>
#include "evsel.h"
#include "cgroup.h"
#include "evlist.h"
#include "rblist.h"
#include "metricgroup.h"
#include "stat.h"
#include <linux/zalloc.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/statfs.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <api/fs/fs.h>
#include <ftw.h>
#include <regex.h>
int nr_cgroups;
bool cgrp_event_expanded;
/* used to match cgroup name with patterns */
struct cgroup_name {
struct list_head list;
bool used;
char name[];
};
static LIST_HEAD(cgroup_list);
static int open_cgroup(const char *name)
{
char path[PATH_MAX + 1];
char mnt[PATH_MAX + 1];
int fd;
if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1, "perf_event"))
return -1;
scnprintf(path, PATH_MAX, "%s/%s", mnt, name);
fd = open(path, O_RDONLY);
if (fd == -1)
fprintf(stderr, "no access to cgroup %s\n", path);
return fd;
}
#ifdef HAVE_FILE_HANDLE
static u64 __read_cgroup_id(const char *path)
{
struct {
struct file_handle fh;
uint64_t cgroup_id;
} handle;
int mount_id;
handle.fh.handle_bytes = sizeof(handle.cgroup_id);
if (name_to_handle_at(AT_FDCWD, path, &handle.fh, &mount_id, 0) < 0)
return -1ULL;
return handle.cgroup_id;
}
int read_cgroup_id(struct cgroup *cgrp)
{
char path[PATH_MAX + 1];
char mnt[PATH_MAX + 1];
if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1, "perf_event"))
return -1;
scnprintf(path, PATH_MAX, "%s/%s", mnt, cgrp->name);
cgrp->id = __read_cgroup_id(path);
return 0;
}
#else
static inline u64 __read_cgroup_id(const char *path __maybe_unused) { return -1ULL; }
#endif /* HAVE_FILE_HANDLE */
#ifndef CGROUP2_SUPER_MAGIC
#define CGROUP2_SUPER_MAGIC 0x63677270
#endif
int cgroup_is_v2(const char *subsys)
{
char mnt[PATH_MAX + 1];
struct statfs stbuf;
if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1, subsys))
return -1;
if (statfs(mnt, &stbuf) < 0)
return -1;
return (stbuf.f_type == CGROUP2_SUPER_MAGIC);
}
static struct cgroup *evlist__find_cgroup(struct evlist *evlist, const char *str)
{
struct evsel *counter;
/*
* check if cgrp is already defined, if so we reuse it
*/
evlist__for_each_entry(evlist, counter) {
if (!counter->cgrp)
continue;
if (!strcmp(counter->cgrp->name, str))
return cgroup__get(counter->cgrp);
}
return NULL;
}
struct cgroup *cgroup__new(const char *name, bool do_open)
{
struct cgroup *cgroup = zalloc(sizeof(*cgroup));
if (cgroup != NULL) {
refcount_set(&cgroup->refcnt, 1);
cgroup->name = strdup(name);
if (!cgroup->name)
goto out_err;
if (do_open) {
cgroup->fd = open_cgroup(name);
if (cgroup->fd == -1)
goto out_free_name;
} else {
cgroup->fd = -1;
}
}
return cgroup;
out_free_name:
zfree(&cgroup->name);
out_err:
free(cgroup);
return NULL;
}
struct cgroup *evlist__findnew_cgroup(struct evlist *evlist, const char *name)
{
struct cgroup *cgroup = evlist__find_cgroup(evlist, name);
return cgroup ?: cgroup__new(name, true);
}
static int add_cgroup(struct evlist *evlist, const char *str)
{
struct evsel *counter;
struct cgroup *cgrp = evlist__findnew_cgroup(evlist, str);
int n;
if (!cgrp)
return -1;
/*
* find corresponding event
* if add cgroup N, then need to find event N
*/
n = 0;
evlist__for_each_entry(evlist, counter) {
if (n == nr_cgroups)
goto found;
n++;
}
cgroup__put(cgrp);
return -1;
found:
counter->cgrp = cgrp;
return 0;
}
static void cgroup__delete(struct cgroup *cgroup)
{
if (cgroup->fd >= 0)
close(cgroup->fd);
zfree(&cgroup->name);
free(cgroup);
}
void cgroup__put(struct cgroup *cgrp)
{
if (cgrp && refcount_dec_and_test(&cgrp->refcnt)) {
cgroup__delete(cgrp);
}
}
struct cgroup *cgroup__get(struct cgroup *cgroup)
{
if (cgroup)
refcount_inc(&cgroup->refcnt);
return cgroup;
}
static void evsel__set_default_cgroup(struct evsel *evsel, struct cgroup *cgroup)
{
if (evsel->cgrp == NULL)
evsel->cgrp = cgroup__get(cgroup);
}
void evlist__set_default_cgroup(struct evlist *evlist, struct cgroup *cgroup)
{
struct evsel *evsel;
evlist__for_each_entry(evlist, evsel)
evsel__set_default_cgroup(evsel, cgroup);
}
/* helper function for ftw() in match_cgroups and list_cgroups */
static int add_cgroup_name(const char *fpath, const struct stat *sb __maybe_unused,
int typeflag, struct FTW *ftwbuf __maybe_unused)
{
struct cgroup_name *cn;
if (typeflag != FTW_D)
return 0;
cn = malloc(sizeof(*cn) + strlen(fpath) + 1);
if (cn == NULL)
return -1;
cn->used = false;
strcpy(cn->name, fpath);
list_add_tail(&cn->list, &cgroup_list);
return 0;
}
static int check_and_add_cgroup_name(const char *fpath)
{
struct cgroup_name *cn;
list_for_each_entry(cn, &cgroup_list, list) {
if (!strcmp(cn->name, fpath))
return 0;
}
/* pretend if it's added by ftw() */
return add_cgroup_name(fpath, NULL, FTW_D, NULL);
}
static void release_cgroup_list(void)
{
struct cgroup_name *cn;
while (!list_empty(&cgroup_list)) {
cn = list_first_entry(&cgroup_list, struct cgroup_name, list);
list_del(&cn->list);
free(cn);
}
}
/* collect given cgroups only */
static int list_cgroups(const char *str)
{
const char *p, *e, *eos = str + strlen(str);
struct cgroup_name *cn;
char *s;
/* use given name as is when no regex is given */
for (;;) {
p = strchr(str, ',');
e = p ? p : eos;
if (e - str) {
int ret;
s = strndup(str, e - str);
if (!s)
return -1;
ret = check_and_add_cgroup_name(s);
free(s);
if (ret < 0)
return -1;
} else {
if (check_and_add_cgroup_name("/") < 0)
return -1;
}
if (!p)
break;
str = p+1;
}
/* these groups will be used */
list_for_each_entry(cn, &cgroup_list, list)
cn->used = true;
return 0;
}
/* collect all cgroups first and then match with the pattern */
static int match_cgroups(const char *str)
{
char mnt[PATH_MAX];
const char *p, *e, *eos = str + strlen(str);
struct cgroup_name *cn;
regex_t reg;
int prefix_len;
char *s;
if (cgroupfs_find_mountpoint(mnt, sizeof(mnt), "perf_event"))
return -1;
/* cgroup_name will have a full path, skip the root directory */
prefix_len = strlen(mnt);
/* collect all cgroups in the cgroup_list */
if (nftw(mnt, add_cgroup_name, 20, 0) < 0)
return -1;
for (;;) {
p = strchr(str, ',');
e = p ? p : eos;
/* allow empty cgroups, i.e., skip */
if (e - str) {
/* termination added */
s = strndup(str, e - str);
if (!s)
return -1;
if (regcomp(®, s, REG_NOSUB)) {
free(s);
return -1;
}
/* check cgroup name with the pattern */
list_for_each_entry(cn, &cgroup_list, list) {
char *name = cn->name + prefix_len;
if (name[0] == '/' && name[1])
name++;
if (!regexec(®, name, 0, NULL, 0))
cn->used = true;
}
regfree(®);
free(s);
} else {
/* first entry to root cgroup */
cn = list_first_entry(&cgroup_list, struct cgroup_name,
list);
cn->used = true;
}
if (!p)
break;
str = p+1;
}
return prefix_len;
}
int parse_cgroups(const struct option *opt, const char *str,
int unset __maybe_unused)
{
struct evlist *evlist = *(struct evlist **)opt->value;
struct evsel *counter;
struct cgroup *cgrp = NULL;
const char *p, *e, *eos = str + strlen(str);
char *s;
int ret, i;
if (list_empty(&evlist->core.entries)) {
fprintf(stderr, "must define events before cgroups\n");
return -1;
}
for (;;) {
p = strchr(str, ',');
e = p ? p : eos;
/* allow empty cgroups, i.e., skip */
if (e - str) {
/* termination added */
s = strndup(str, e - str);
if (!s)
return -1;
ret = add_cgroup(evlist, s);
free(s);
if (ret)
return -1;
}
/* nr_cgroups is increased een for empty cgroups */
nr_cgroups++;
if (!p)
break;
str = p+1;
}
/* for the case one cgroup combine to multiple events */
i = 0;
if (nr_cgroups == 1) {
evlist__for_each_entry(evlist, counter) {
if (i == 0)
cgrp = counter->cgrp;
else {
counter->cgrp = cgrp;
refcount_inc(&cgrp->refcnt);
}
i++;
}
}
return 0;
}
static bool has_pattern_string(const char *str)
{
return !!strpbrk(str, "{}[]()|*+?^$");
}
int evlist__expand_cgroup(struct evlist *evlist, const char *str,
struct rblist *metric_events, bool open_cgroup)
{
struct evlist *orig_list, *tmp_list;
struct evsel *pos, *evsel, *leader;
struct rblist orig_metric_events;
struct cgroup *cgrp = NULL;
struct cgroup_name *cn;
int ret = -1;
int prefix_len;
if (evlist->core.nr_entries == 0) {
fprintf(stderr, "must define events before cgroups\n");
return -EINVAL;
}
orig_list = evlist__new();
tmp_list = evlist__new();
if (orig_list == NULL || tmp_list == NULL) {
fprintf(stderr, "memory allocation failed\n");
return -ENOMEM;
}
/* save original events and init evlist */
evlist__splice_list_tail(orig_list, &evlist->core.entries);
evlist->core.nr_entries = 0;
if (metric_events) {
orig_metric_events = *metric_events;
rblist__init(metric_events);
} else {
rblist__init(&orig_metric_events);
}
if (has_pattern_string(str))
prefix_len = match_cgroups(str);
else
prefix_len = list_cgroups(str);
if (prefix_len < 0)
goto out_err;
list_for_each_entry(cn, &cgroup_list, list) {
char *name;
if (!cn->used)
continue;
/* cgroup_name might have a full path, skip the prefix */
name = cn->name + prefix_len;
if (name[0] == '/' && name[1])
name++;
/* the cgroup can go away in the meantime */
cgrp = cgroup__new(name, open_cgroup);
if (cgrp == NULL)
continue;
leader = NULL;
evlist__for_each_entry(orig_list, pos) {
evsel = evsel__clone(pos);
if (evsel == NULL)
goto out_err;
cgroup__put(evsel->cgrp);
evsel->cgrp = cgroup__get(cgrp);
if (evsel__is_group_leader(pos))
leader = evsel;
evsel__set_leader(evsel, leader);
evlist__add(tmp_list, evsel);
}
/* cgroup__new() has a refcount, release it here */
cgroup__put(cgrp);
nr_cgroups++;
if (metric_events) {
if (metricgroup__copy_metric_events(tmp_list, cgrp,
metric_events,
&orig_metric_events) < 0)
goto out_err;
}
evlist__splice_list_tail(evlist, &tmp_list->core.entries);
tmp_list->core.nr_entries = 0;
}
if (list_empty(&evlist->core.entries)) {
fprintf(stderr, "no cgroup matched: %s\n", str);
goto out_err;
}
ret = 0;
cgrp_event_expanded = true;
out_err:
evlist__delete(orig_list);
evlist__delete(tmp_list);
rblist__exit(&orig_metric_events);
release_cgroup_list();
return ret;
}
static struct cgroup *__cgroup__findnew(struct rb_root *root, uint64_t id,
bool create, const char *path)
{
struct rb_node **p = &root->rb_node;
struct rb_node *parent = NULL;
struct cgroup *cgrp;
while (*p != NULL) {
parent = *p;
cgrp = rb_entry(parent, struct cgroup, node);
if (cgrp->id == id)
return cgrp;
if (cgrp->id < id)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
if (!create)
return NULL;
cgrp = malloc(sizeof(*cgrp));
if (cgrp == NULL)
return NULL;
cgrp->name = strdup(path);
if (cgrp->name == NULL) {
free(cgrp);
return NULL;
}
cgrp->fd = -1;
cgrp->id = id;
refcount_set(&cgrp->refcnt, 1);
rb_link_node(&cgrp->node, parent, p);
rb_insert_color(&cgrp->node, root);
return cgrp;
}
struct cgroup *cgroup__findnew(struct perf_env *env, uint64_t id,
const char *path)
{
struct cgroup *cgrp;
down_write(&env->cgroups.lock);
cgrp = __cgroup__findnew(&env->cgroups.tree, id, true, path);
up_write(&env->cgroups.lock);
return cgrp;
}
struct cgroup *__cgroup__find(struct rb_root *root, uint64_t id)
{
return __cgroup__findnew(root, id, /*create=*/false, /*path=*/NULL);
}
struct cgroup *cgroup__find(struct perf_env *env, uint64_t id)
{
struct cgroup *cgrp;
down_read(&env->cgroups.lock);
cgrp = __cgroup__findnew(&env->cgroups.tree, id, false, NULL);
up_read(&env->cgroups.lock);
return cgrp;
}
void perf_env__purge_cgroups(struct perf_env *env)
{
struct rb_node *node;
struct cgroup *cgrp;
down_write(&env->cgroups.lock);
while (!RB_EMPTY_ROOT(&env->cgroups.tree)) {
node = rb_first(&env->cgroups.tree);
cgrp = rb_entry(node, struct cgroup, node);
rb_erase(node, &env->cgroups.tree);
cgroup__put(cgrp);
}
up_write(&env->cgroups.lock);
}
void read_all_cgroups(struct rb_root *root)
{
char mnt[PATH_MAX];
struct cgroup_name *cn;
int prefix_len;
if (cgroupfs_find_mountpoint(mnt, sizeof(mnt), "perf_event"))
return;
/* cgroup_name will have a full path, skip the root directory */
prefix_len = strlen(mnt);
/* collect all cgroups in the cgroup_list */
if (nftw(mnt, add_cgroup_name, 20, 0) < 0)
return;
list_for_each_entry(cn, &cgroup_list, list) {
const char *name;
u64 cgrp_id;
/* cgroup_name might have a full path, skip the prefix */
name = cn->name + prefix_len;
if (name[0] == '\0')
name = "/";
cgrp_id = __read_cgroup_id(cn->name);
__cgroup__findnew(root, cgrp_id, /*create=*/true, name);
}
release_cgroup_list();
}
|