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d58d1454 | 1 | /* |
c0c0989a | 2 | * SPDX-License-Identifier: LGPL-2.1-only |
d58d1454 MD |
3 | * |
4 | * Copyright (C) 2009-2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
c0c0989a | 6 | * LTTng UST performance monitoring counters (perf-counters) integration. |
d58d1454 MD |
7 | */ |
8 | ||
3fbec7dc | 9 | #define _LGPL_SOURCE |
9af5d97a | 10 | #include <limits.h> |
d58d1454 MD |
11 | #include <sys/types.h> |
12 | #include <unistd.h> | |
13 | #include <string.h> | |
14 | #include <stdlib.h> | |
15 | #include <stdio.h> | |
649fb6b3 | 16 | #include <stdbool.h> |
b4051ad8 | 17 | #include <stddef.h> |
fb31eb73 | 18 | #include <stdint.h> |
d58d1454 MD |
19 | #include <sys/mman.h> |
20 | #include <sys/syscall.h> | |
2eba8e39 | 21 | #include <lttng/ust-arch.h> |
d58d1454 MD |
22 | #include <lttng/ust-events.h> |
23 | #include <lttng/ust-tracer.h> | |
0466ac28 | 24 | #include <lttng/ringbuffer-context.h> |
d58d1454 MD |
25 | #include <urcu/system.h> |
26 | #include <urcu/arch.h> | |
27 | #include <urcu/rculist.h> | |
9d315d6d | 28 | #include "common/macros.h" |
d58d1454 | 29 | #include <urcu/ref.h> |
9d315d6d | 30 | #include "common/logging.h" |
d58d1454 | 31 | #include <signal.h> |
20142124 | 32 | #include <urcu/tls-compat.h> |
77d7fa98 | 33 | #include "perf_event.h" |
fc80554e MJ |
34 | |
35 | #include "context-internal.h" | |
d58d1454 | 36 | #include "lttng-tracer-core.h" |
bd8c1787 | 37 | #include "ust-events-internal.h" |
d58d1454 MD |
38 | |
39 | /* | |
40 | * We use a global perf counter key and iterate on per-thread RCU lists | |
41 | * of fields in the fast path, even though this is not strictly speaking | |
42 | * what would provide the best fast-path complexity, to ensure teardown | |
43 | * of sessions vs thread exit is handled racelessly. | |
44 | * | |
45 | * Updates and traversals of thread_list are protected by UST lock. | |
46 | * Updates to rcu_field_list are protected by UST lock. | |
47 | */ | |
48 | ||
49 | struct lttng_perf_counter_thread_field { | |
50 | struct lttng_perf_counter_field *field; /* Back reference */ | |
51 | struct perf_event_mmap_page *pc; | |
52 | struct cds_list_head thread_field_node; /* Per-field list of thread fields (node) */ | |
53 | struct cds_list_head rcu_field_node; /* RCU per-thread list of fields (node) */ | |
b9389e6e | 54 | int fd; /* Perf FD */ |
d58d1454 MD |
55 | }; |
56 | ||
57 | struct lttng_perf_counter_thread { | |
58 | struct cds_list_head rcu_field_list; /* RCU per-thread list of fields */ | |
59 | }; | |
60 | ||
61 | struct lttng_perf_counter_field { | |
62 | struct perf_event_attr attr; | |
63 | struct cds_list_head thread_field_list; /* Per-field list of thread fields */ | |
4e48b5d2 | 64 | char *name; |
d58d1454 MD |
65 | }; |
66 | ||
67 | static pthread_key_t perf_counter_key; | |
68 | ||
20142124 MD |
69 | /* |
70 | * lttng_perf_lock - Protect lttng-ust perf counter data structures | |
71 | * | |
72 | * Nests within the ust_lock, and therefore within the libc dl lock. | |
73 | * Therefore, we need to fixup the TLS before nesting into this lock. | |
74 | * Nests inside RCU bp read-side lock. Protects against concurrent | |
75 | * fork. | |
76 | */ | |
77 | static pthread_mutex_t ust_perf_mutex = PTHREAD_MUTEX_INITIALIZER; | |
78 | ||
79 | /* | |
80 | * Cancel state when grabbing the ust_perf_mutex. Saved when locking, | |
81 | * restored on unlock. Protected by ust_perf_mutex. | |
82 | */ | |
83 | static int ust_perf_saved_cancelstate; | |
84 | ||
85 | /* | |
86 | * Track whether we are tracing from a signal handler nested on an | |
87 | * application thread. | |
88 | */ | |
89 | static DEFINE_URCU_TLS(int, ust_perf_mutex_nest); | |
90 | ||
91 | /* | |
92 | * Force a read (imply TLS fixup for dlopen) of TLS variables. | |
93 | */ | |
94 | void lttng_ust_fixup_perf_counter_tls(void) | |
95 | { | |
96 | asm volatile ("" : : "m" (URCU_TLS(ust_perf_mutex_nest))); | |
97 | } | |
98 | ||
99 | void lttng_perf_lock(void) | |
100 | { | |
101 | sigset_t sig_all_blocked, orig_mask; | |
102 | int ret, oldstate; | |
103 | ||
104 | ret = pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldstate); | |
105 | if (ret) { | |
106 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
107 | } | |
108 | sigfillset(&sig_all_blocked); | |
109 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
110 | if (ret) { | |
111 | ERR("pthread_sigmask: %s", strerror(ret)); | |
112 | } | |
113 | if (!URCU_TLS(ust_perf_mutex_nest)++) { | |
114 | /* | |
115 | * Ensure the compiler don't move the store after the close() | |
116 | * call in case close() would be marked as leaf. | |
117 | */ | |
118 | cmm_barrier(); | |
119 | pthread_mutex_lock(&ust_perf_mutex); | |
120 | ust_perf_saved_cancelstate = oldstate; | |
121 | } | |
122 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
123 | if (ret) { | |
124 | ERR("pthread_sigmask: %s", strerror(ret)); | |
125 | } | |
126 | } | |
127 | ||
128 | void lttng_perf_unlock(void) | |
129 | { | |
130 | sigset_t sig_all_blocked, orig_mask; | |
131 | int ret, newstate, oldstate; | |
132 | bool restore_cancel = false; | |
133 | ||
134 | sigfillset(&sig_all_blocked); | |
135 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
136 | if (ret) { | |
137 | ERR("pthread_sigmask: %s", strerror(ret)); | |
138 | } | |
139 | /* | |
140 | * Ensure the compiler don't move the store before the close() | |
141 | * call, in case close() would be marked as leaf. | |
142 | */ | |
143 | cmm_barrier(); | |
144 | if (!--URCU_TLS(ust_perf_mutex_nest)) { | |
145 | newstate = ust_perf_saved_cancelstate; | |
146 | restore_cancel = true; | |
147 | pthread_mutex_unlock(&ust_perf_mutex); | |
148 | } | |
149 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
150 | if (ret) { | |
151 | ERR("pthread_sigmask: %s", strerror(ret)); | |
152 | } | |
153 | if (restore_cancel) { | |
154 | ret = pthread_setcancelstate(newstate, &oldstate); | |
155 | if (ret) { | |
156 | ERR("pthread_setcancelstate: %s", strerror(ret)); | |
157 | } | |
158 | } | |
159 | } | |
160 | ||
d58d1454 | 161 | static |
4e48b5d2 | 162 | size_t perf_counter_get_size(void *priv __attribute__((unused)), |
2208d8b5 | 163 | size_t offset) |
d58d1454 MD |
164 | { |
165 | size_t size = 0; | |
166 | ||
dc325c1d | 167 | size += lttng_ust_lib_ring_buffer_align(offset, lttng_ust_rb_alignof(uint64_t)); |
d58d1454 MD |
168 | size += sizeof(uint64_t); |
169 | return size; | |
170 | } | |
171 | ||
a3a8d943 MD |
172 | static |
173 | uint64_t read_perf_counter_syscall( | |
174 | struct lttng_perf_counter_thread_field *thread_field) | |
175 | { | |
176 | uint64_t count; | |
177 | ||
178 | if (caa_unlikely(thread_field->fd < 0)) | |
179 | return 0; | |
180 | ||
181 | if (caa_unlikely(read(thread_field->fd, &count, sizeof(count)) | |
182 | < sizeof(count))) | |
183 | return 0; | |
184 | ||
185 | return count; | |
186 | } | |
187 | ||
2eba8e39 | 188 | #if defined(LTTNG_UST_ARCH_X86) |
d58d1454 MD |
189 | |
190 | static | |
191 | uint64_t rdpmc(unsigned int counter) | |
192 | { | |
193 | unsigned int low, high; | |
194 | ||
195 | asm volatile("rdpmc" : "=a" (low), "=d" (high) : "c" (counter)); | |
196 | ||
197 | return low | ((uint64_t) high) << 32; | |
198 | } | |
199 | ||
77d7fa98 MD |
200 | static |
201 | bool has_rdpmc(struct perf_event_mmap_page *pc) | |
202 | { | |
203 | if (caa_unlikely(!pc->cap_bit0_is_deprecated)) | |
204 | return false; | |
205 | /* Since Linux kernel 3.12. */ | |
206 | return pc->cap_user_rdpmc; | |
207 | } | |
208 | ||
d58d1454 | 209 | static |
a3a8d943 | 210 | uint64_t arch_read_perf_counter( |
d286ad50 | 211 | struct lttng_perf_counter_thread_field *thread_field) |
d58d1454 MD |
212 | { |
213 | uint32_t seq, idx; | |
214 | uint64_t count; | |
d286ad50 | 215 | struct perf_event_mmap_page *pc = thread_field->pc; |
d58d1454 MD |
216 | |
217 | if (caa_unlikely(!pc)) | |
218 | return 0; | |
219 | ||
220 | do { | |
221 | seq = CMM_LOAD_SHARED(pc->lock); | |
222 | cmm_barrier(); | |
223 | ||
224 | idx = pc->index; | |
77d7fa98 | 225 | if (caa_likely(has_rdpmc(pc) && idx)) { |
4f58f54f MD |
226 | int64_t pmcval; |
227 | ||
228 | pmcval = rdpmc(idx - 1); | |
229 | /* Sign-extend the pmc register result. */ | |
230 | pmcval <<= 64 - pc->pmc_width; | |
231 | pmcval >>= 64 - pc->pmc_width; | |
232 | count = pc->offset + pmcval; | |
233 | } else { | |
a3a8d943 MD |
234 | /* Fall-back on system call if rdpmc cannot be used. */ |
235 | return read_perf_counter_syscall(thread_field); | |
4f58f54f | 236 | } |
d58d1454 MD |
237 | cmm_barrier(); |
238 | } while (CMM_LOAD_SHARED(pc->lock) != seq); | |
239 | ||
240 | return count; | |
241 | } | |
242 | ||
d286ad50 | 243 | static |
a3a8d943 | 244 | int arch_perf_keep_fd(struct lttng_perf_counter_thread_field *thread_field) |
d286ad50 | 245 | { |
a3a8d943 | 246 | struct perf_event_mmap_page *pc = thread_field->pc; |
d286ad50 | 247 | |
a3a8d943 | 248 | if (!pc) |
d286ad50 | 249 | return 0; |
77d7fa98 | 250 | return !has_rdpmc(pc); |
a3a8d943 | 251 | } |
d286ad50 | 252 | |
a3a8d943 | 253 | #else |
d286ad50 | 254 | |
a3a8d943 MD |
255 | /* Generic (slow) implementation using a read system call. */ |
256 | static | |
257 | uint64_t arch_read_perf_counter( | |
258 | struct lttng_perf_counter_thread_field *thread_field) | |
259 | { | |
260 | return read_perf_counter_syscall(thread_field); | |
d286ad50 JD |
261 | } |
262 | ||
a3a8d943 MD |
263 | static |
264 | int arch_perf_keep_fd(struct lttng_perf_counter_thread_field *thread_field) | |
265 | { | |
266 | return 1; | |
267 | } | |
d286ad50 | 268 | |
a3a8d943 | 269 | #endif |
d286ad50 | 270 | |
d58d1454 MD |
271 | static |
272 | int sys_perf_event_open(struct perf_event_attr *attr, | |
273 | pid_t pid, int cpu, int group_fd, | |
274 | unsigned long flags) | |
275 | { | |
276 | return syscall(SYS_perf_event_open, attr, pid, cpu, | |
277 | group_fd, flags); | |
278 | } | |
279 | ||
280 | static | |
b9389e6e | 281 | int open_perf_fd(struct perf_event_attr *attr) |
d58d1454 | 282 | { |
b9389e6e | 283 | int fd; |
d58d1454 MD |
284 | |
285 | fd = sys_perf_event_open(attr, 0, -1, -1, 0); | |
286 | if (fd < 0) | |
b9389e6e JD |
287 | return -1; |
288 | ||
289 | return fd; | |
290 | } | |
291 | ||
d286ad50 JD |
292 | static |
293 | void close_perf_fd(int fd) | |
294 | { | |
295 | int ret; | |
296 | ||
297 | if (fd < 0) | |
298 | return; | |
299 | ||
300 | ret = close(fd); | |
301 | if (ret) { | |
302 | perror("Error closing LTTng-UST perf memory mapping FD"); | |
303 | } | |
304 | } | |
305 | ||
77d7fa98 | 306 | static void setup_perf(struct lttng_perf_counter_thread_field *thread_field) |
b9389e6e JD |
307 | { |
308 | void *perf_addr; | |
d58d1454 MD |
309 | |
310 | perf_addr = mmap(NULL, sizeof(struct perf_event_mmap_page), | |
b9389e6e | 311 | PROT_READ, MAP_SHARED, thread_field->fd, 0); |
d58d1454 | 312 | if (perf_addr == MAP_FAILED) |
b9389e6e | 313 | perf_addr = NULL; |
77d7fa98 | 314 | thread_field->pc = perf_addr; |
b9389e6e | 315 | |
a3a8d943 | 316 | if (!arch_perf_keep_fd(thread_field)) { |
b9389e6e JD |
317 | close_perf_fd(thread_field->fd); |
318 | thread_field->fd = -1; | |
6c2125af | 319 | } |
d58d1454 MD |
320 | } |
321 | ||
322 | static | |
323 | void unmap_perf_page(struct perf_event_mmap_page *pc) | |
324 | { | |
325 | int ret; | |
326 | ||
327 | if (!pc) | |
328 | return; | |
329 | ret = munmap(pc, sizeof(struct perf_event_mmap_page)); | |
330 | if (ret < 0) { | |
331 | PERROR("Error in munmap"); | |
332 | abort(); | |
333 | } | |
334 | } | |
335 | ||
336 | static | |
337 | struct lttng_perf_counter_thread *alloc_perf_counter_thread(void) | |
338 | { | |
339 | struct lttng_perf_counter_thread *perf_thread; | |
340 | sigset_t newmask, oldmask; | |
341 | int ret; | |
342 | ||
343 | ret = sigfillset(&newmask); | |
344 | if (ret) | |
345 | abort(); | |
346 | ret = pthread_sigmask(SIG_BLOCK, &newmask, &oldmask); | |
347 | if (ret) | |
348 | abort(); | |
349 | /* Check again with signals disabled */ | |
350 | perf_thread = pthread_getspecific(perf_counter_key); | |
351 | if (perf_thread) | |
352 | goto skip; | |
353 | perf_thread = zmalloc(sizeof(*perf_thread)); | |
354 | if (!perf_thread) | |
355 | abort(); | |
356 | CDS_INIT_LIST_HEAD(&perf_thread->rcu_field_list); | |
357 | ret = pthread_setspecific(perf_counter_key, perf_thread); | |
358 | if (ret) | |
359 | abort(); | |
360 | skip: | |
361 | ret = pthread_sigmask(SIG_SETMASK, &oldmask, NULL); | |
362 | if (ret) | |
363 | abort(); | |
364 | return perf_thread; | |
365 | } | |
366 | ||
367 | static | |
368 | struct lttng_perf_counter_thread_field * | |
369 | add_thread_field(struct lttng_perf_counter_field *perf_field, | |
370 | struct lttng_perf_counter_thread *perf_thread) | |
371 | { | |
372 | struct lttng_perf_counter_thread_field *thread_field; | |
373 | sigset_t newmask, oldmask; | |
374 | int ret; | |
375 | ||
376 | ret = sigfillset(&newmask); | |
377 | if (ret) | |
378 | abort(); | |
379 | ret = pthread_sigmask(SIG_BLOCK, &newmask, &oldmask); | |
380 | if (ret) | |
381 | abort(); | |
382 | /* Check again with signals disabled */ | |
383 | cds_list_for_each_entry_rcu(thread_field, &perf_thread->rcu_field_list, | |
384 | rcu_field_node) { | |
385 | if (thread_field->field == perf_field) | |
386 | goto skip; | |
387 | } | |
388 | thread_field = zmalloc(sizeof(*thread_field)); | |
389 | if (!thread_field) | |
390 | abort(); | |
391 | thread_field->field = perf_field; | |
b9389e6e JD |
392 | thread_field->fd = open_perf_fd(&perf_field->attr); |
393 | if (thread_field->fd >= 0) | |
77d7fa98 | 394 | setup_perf(thread_field); |
b9389e6e JD |
395 | /* |
396 | * Note: thread_field->pc can be NULL if setup_perf() fails. | |
397 | * Also, thread_field->fd can be -1 if open_perf_fd() fails. | |
398 | */ | |
20142124 | 399 | lttng_perf_lock(); |
d58d1454 MD |
400 | cds_list_add_rcu(&thread_field->rcu_field_node, |
401 | &perf_thread->rcu_field_list); | |
402 | cds_list_add(&thread_field->thread_field_node, | |
403 | &perf_field->thread_field_list); | |
20142124 | 404 | lttng_perf_unlock(); |
d58d1454 MD |
405 | skip: |
406 | ret = pthread_sigmask(SIG_SETMASK, &oldmask, NULL); | |
407 | if (ret) | |
408 | abort(); | |
409 | return thread_field; | |
410 | } | |
411 | ||
412 | static | |
413 | struct lttng_perf_counter_thread_field * | |
414 | get_thread_field(struct lttng_perf_counter_field *field) | |
415 | { | |
416 | struct lttng_perf_counter_thread *perf_thread; | |
417 | struct lttng_perf_counter_thread_field *thread_field; | |
418 | ||
419 | perf_thread = pthread_getspecific(perf_counter_key); | |
420 | if (!perf_thread) | |
421 | perf_thread = alloc_perf_counter_thread(); | |
422 | cds_list_for_each_entry_rcu(thread_field, &perf_thread->rcu_field_list, | |
423 | rcu_field_node) { | |
424 | if (thread_field->field == field) | |
425 | return thread_field; | |
426 | } | |
427 | /* perf_counter_thread_field not found, need to add one */ | |
428 | return add_thread_field(field, perf_thread); | |
429 | } | |
430 | ||
431 | static | |
4e48b5d2 | 432 | uint64_t wrapper_perf_counter_read(void *priv) |
d58d1454 MD |
433 | { |
434 | struct lttng_perf_counter_field *perf_field; | |
435 | struct lttng_perf_counter_thread_field *perf_thread_field; | |
436 | ||
4e48b5d2 | 437 | perf_field = (struct lttng_perf_counter_field *) priv; |
d58d1454 | 438 | perf_thread_field = get_thread_field(perf_field); |
a3a8d943 | 439 | return arch_read_perf_counter(perf_thread_field); |
d58d1454 MD |
440 | } |
441 | ||
442 | static | |
4e48b5d2 | 443 | void perf_counter_record(void *priv, |
d58d1454 | 444 | struct lttng_ust_lib_ring_buffer_ctx *ctx, |
e7bc0ef6 | 445 | struct lttng_ust_channel_buffer *chan) |
d58d1454 MD |
446 | { |
447 | uint64_t value; | |
448 | ||
4e48b5d2 | 449 | value = wrapper_perf_counter_read(priv); |
8936b6c0 | 450 | chan->ops->event_write(ctx, &value, sizeof(value), lttng_ust_rb_alignof(value)); |
d58d1454 MD |
451 | } |
452 | ||
453 | static | |
4e48b5d2 | 454 | void perf_counter_get_value(void *priv, |
daacdbfc | 455 | struct lttng_ust_ctx_value *value) |
d58d1454 | 456 | { |
4e48b5d2 | 457 | value->u.s64 = wrapper_perf_counter_read(priv); |
d58d1454 MD |
458 | } |
459 | ||
20142124 | 460 | /* Called with perf lock held */ |
d58d1454 MD |
461 | static |
462 | void lttng_destroy_perf_thread_field( | |
463 | struct lttng_perf_counter_thread_field *thread_field) | |
464 | { | |
b9389e6e | 465 | close_perf_fd(thread_field->fd); |
d58d1454 MD |
466 | unmap_perf_page(thread_field->pc); |
467 | cds_list_del_rcu(&thread_field->rcu_field_node); | |
468 | cds_list_del(&thread_field->thread_field_node); | |
469 | free(thread_field); | |
470 | } | |
471 | ||
472 | static | |
473 | void lttng_destroy_perf_thread_key(void *_key) | |
474 | { | |
475 | struct lttng_perf_counter_thread *perf_thread = _key; | |
476 | struct lttng_perf_counter_thread_field *pos, *p; | |
477 | ||
20142124 | 478 | lttng_perf_lock(); |
d58d1454 MD |
479 | cds_list_for_each_entry_safe(pos, p, &perf_thread->rcu_field_list, |
480 | rcu_field_node) | |
481 | lttng_destroy_perf_thread_field(pos); | |
20142124 | 482 | lttng_perf_unlock(); |
d58d1454 MD |
483 | free(perf_thread); |
484 | } | |
485 | ||
486 | /* Called with UST lock held */ | |
487 | static | |
4e48b5d2 | 488 | void lttng_destroy_perf_counter_ctx_field(void *priv) |
d58d1454 MD |
489 | { |
490 | struct lttng_perf_counter_field *perf_field; | |
491 | struct lttng_perf_counter_thread_field *pos, *p; | |
492 | ||
4e48b5d2 MD |
493 | perf_field = (struct lttng_perf_counter_field *) priv; |
494 | free(perf_field->name); | |
d58d1454 MD |
495 | /* |
496 | * This put is performed when no threads can concurrently | |
497 | * perform a "get" concurrently, thanks to urcu-bp grace | |
20142124 MD |
498 | * period. Holding the lttng perf lock protects against |
499 | * concurrent modification of the per-thread thread field | |
500 | * list. | |
d58d1454 | 501 | */ |
20142124 | 502 | lttng_perf_lock(); |
d58d1454 MD |
503 | cds_list_for_each_entry_safe(pos, p, &perf_field->thread_field_list, |
504 | thread_field_node) | |
505 | lttng_destroy_perf_thread_field(pos); | |
20142124 | 506 | lttng_perf_unlock(); |
d58d1454 MD |
507 | free(perf_field); |
508 | } | |
509 | ||
2eba8e39 | 510 | #ifdef LTTNG_UST_ARCH_ARMV7 |
d286ad50 JD |
511 | |
512 | static | |
513 | int perf_get_exclude_kernel(void) | |
514 | { | |
515 | return 0; | |
516 | } | |
517 | ||
2eba8e39 | 518 | #else /* LTTNG_UST_ARCH_ARMV7 */ |
d286ad50 JD |
519 | |
520 | static | |
521 | int perf_get_exclude_kernel(void) | |
522 | { | |
523 | return 1; | |
524 | } | |
525 | ||
2eba8e39 | 526 | #endif /* LTTNG_UST_ARCH_ARMV7 */ |
d286ad50 | 527 | |
4e48b5d2 MD |
528 | static const struct lttng_ust_type_common *ust_type = |
529 | lttng_ust_static_type_integer(sizeof(uint64_t) * CHAR_BIT, | |
530 | lttng_ust_rb_alignof(uint64_t) * CHAR_BIT, | |
531 | lttng_ust_is_signed_type(uint64_t), | |
532 | BYTE_ORDER, 10); | |
533 | ||
d58d1454 MD |
534 | /* Called with UST lock held */ |
535 | int lttng_add_perf_counter_to_ctx(uint32_t type, | |
536 | uint64_t config, | |
537 | const char *name, | |
daacdbfc | 538 | struct lttng_ust_ctx **ctx) |
d58d1454 | 539 | { |
4e48b5d2 MD |
540 | struct lttng_ust_ctx_field ctx_field; |
541 | struct lttng_ust_event_field *event_field; | |
d58d1454 | 542 | struct lttng_perf_counter_field *perf_field; |
d58d1454 MD |
543 | char *name_alloc; |
544 | int ret; | |
545 | ||
4e48b5d2 MD |
546 | if (lttng_find_context(*ctx, name)) { |
547 | ret = -EEXIST; | |
548 | goto find_error; | |
549 | } | |
d58d1454 MD |
550 | name_alloc = strdup(name); |
551 | if (!name_alloc) { | |
552 | ret = -ENOMEM; | |
553 | goto name_alloc_error; | |
554 | } | |
4e48b5d2 MD |
555 | event_field = zmalloc(sizeof(*event_field)); |
556 | if (!event_field) { | |
557 | ret = -ENOMEM; | |
558 | goto event_field_alloc_error; | |
559 | } | |
560 | event_field->name = name_alloc; | |
561 | event_field->type = ust_type; | |
562 | ||
d58d1454 MD |
563 | perf_field = zmalloc(sizeof(*perf_field)); |
564 | if (!perf_field) { | |
565 | ret = -ENOMEM; | |
566 | goto perf_field_alloc_error; | |
567 | } | |
d58d1454 MD |
568 | perf_field->attr.type = type; |
569 | perf_field->attr.config = config; | |
d286ad50 | 570 | perf_field->attr.exclude_kernel = perf_get_exclude_kernel(); |
d58d1454 | 571 | CDS_INIT_LIST_HEAD(&perf_field->thread_field_list); |
4e48b5d2 | 572 | perf_field->name = name_alloc; |
d58d1454 MD |
573 | |
574 | /* Ensure that this perf counter can be used in this process. */ | |
b9389e6e JD |
575 | ret = open_perf_fd(&perf_field->attr); |
576 | if (ret < 0) { | |
d58d1454 MD |
577 | ret = -ENODEV; |
578 | goto setup_error; | |
579 | } | |
b9389e6e | 580 | close_perf_fd(ret); |
d58d1454 | 581 | |
4e48b5d2 MD |
582 | ctx_field.event_field = event_field; |
583 | ctx_field.get_size = perf_counter_get_size; | |
584 | ctx_field.record = perf_counter_record; | |
585 | ctx_field.get_value = perf_counter_get_value; | |
586 | ctx_field.destroy = lttng_destroy_perf_counter_ctx_field; | |
587 | ctx_field.priv = perf_field; | |
d58d1454 | 588 | |
4e48b5d2 MD |
589 | ret = lttng_ust_context_append(ctx, &ctx_field); |
590 | if (ret) { | |
591 | ret = -ENOMEM; | |
592 | goto append_context_error; | |
593 | } | |
d58d1454 MD |
594 | return 0; |
595 | ||
d58d1454 | 596 | append_context_error: |
4e48b5d2 | 597 | setup_error: |
d58d1454 MD |
598 | free(perf_field); |
599 | perf_field_alloc_error: | |
4e48b5d2 MD |
600 | free(event_field); |
601 | event_field_alloc_error: | |
d58d1454 MD |
602 | free(name_alloc); |
603 | name_alloc_error: | |
4e48b5d2 | 604 | find_error: |
d58d1454 MD |
605 | return ret; |
606 | } | |
607 | ||
608 | int lttng_perf_counter_init(void) | |
609 | { | |
610 | int ret; | |
611 | ||
612 | ret = pthread_key_create(&perf_counter_key, | |
613 | lttng_destroy_perf_thread_key); | |
614 | if (ret) | |
615 | ret = -ret; | |
616 | return ret; | |
617 | } | |
618 | ||
619 | void lttng_perf_counter_exit(void) | |
620 | { | |
621 | int ret; | |
622 | ||
623 | ret = pthread_key_delete(perf_counter_key); | |
624 | if (ret) { | |
625 | errno = ret; | |
626 | PERROR("Error in pthread_key_delete"); | |
627 | } | |
628 | } |