Commit | Line | Data |
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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> | |
0b4b8811 | 24 | #include <lttng/ust-ringbuffer-context.h> |
59e57035 | 25 | #include <lttng/ust-cancelstate.h> |
d58d1454 MD |
26 | #include <urcu/system.h> |
27 | #include <urcu/arch.h> | |
28 | #include <urcu/rculist.h> | |
9d315d6d | 29 | #include "common/macros.h" |
d58d1454 | 30 | #include <urcu/ref.h> |
9d315d6d | 31 | #include "common/logging.h" |
d58d1454 | 32 | #include <signal.h> |
20142124 | 33 | #include <urcu/tls-compat.h> |
77d7fa98 | 34 | #include "perf_event.h" |
fc80554e MJ |
35 | |
36 | #include "context-internal.h" | |
d58d1454 | 37 | #include "lttng-tracer-core.h" |
36c52fff | 38 | #include "lib/lttng-ust/events.h" |
d58d1454 MD |
39 | |
40 | /* | |
41 | * We use a global perf counter key and iterate on per-thread RCU lists | |
42 | * of fields in the fast path, even though this is not strictly speaking | |
43 | * what would provide the best fast-path complexity, to ensure teardown | |
44 | * of sessions vs thread exit is handled racelessly. | |
45 | * | |
46 | * Updates and traversals of thread_list are protected by UST lock. | |
47 | * Updates to rcu_field_list are protected by UST lock. | |
48 | */ | |
49 | ||
50 | struct lttng_perf_counter_thread_field { | |
51 | struct lttng_perf_counter_field *field; /* Back reference */ | |
52 | struct perf_event_mmap_page *pc; | |
53 | struct cds_list_head thread_field_node; /* Per-field list of thread fields (node) */ | |
54 | struct cds_list_head rcu_field_node; /* RCU per-thread list of fields (node) */ | |
b9389e6e | 55 | int fd; /* Perf FD */ |
d58d1454 MD |
56 | }; |
57 | ||
58 | struct lttng_perf_counter_thread { | |
59 | struct cds_list_head rcu_field_list; /* RCU per-thread list of fields */ | |
60 | }; | |
61 | ||
62 | struct lttng_perf_counter_field { | |
63 | struct perf_event_attr attr; | |
64 | struct cds_list_head thread_field_list; /* Per-field list of thread fields */ | |
4e48b5d2 | 65 | char *name; |
f72cd4d9 | 66 | struct lttng_ust_event_field *event_field; |
d58d1454 MD |
67 | }; |
68 | ||
69 | static pthread_key_t perf_counter_key; | |
70 | ||
20142124 MD |
71 | /* |
72 | * lttng_perf_lock - Protect lttng-ust perf counter data structures | |
73 | * | |
74 | * Nests within the ust_lock, and therefore within the libc dl lock. | |
a9fd951a | 75 | * Therefore, we need to allocate the TLS before nesting into this lock. |
20142124 MD |
76 | * Nests inside RCU bp read-side lock. Protects against concurrent |
77 | * fork. | |
78 | */ | |
79 | static pthread_mutex_t ust_perf_mutex = PTHREAD_MUTEX_INITIALIZER; | |
80 | ||
20142124 MD |
81 | /* |
82 | * Track whether we are tracing from a signal handler nested on an | |
83 | * application thread. | |
84 | */ | |
85 | static DEFINE_URCU_TLS(int, ust_perf_mutex_nest); | |
86 | ||
87 | /* | |
a9fd951a | 88 | * Force a read (imply TLS allocation for dlopen) of TLS variables. |
20142124 | 89 | */ |
a9fd951a | 90 | void lttng_ust_perf_counter_alloc_tls(void) |
20142124 MD |
91 | { |
92 | asm volatile ("" : : "m" (URCU_TLS(ust_perf_mutex_nest))); | |
93 | } | |
94 | ||
95 | void lttng_perf_lock(void) | |
96 | { | |
97 | sigset_t sig_all_blocked, orig_mask; | |
59e57035 | 98 | int ret; |
20142124 | 99 | |
59e57035 MD |
100 | if (lttng_ust_cancelstate_disable_push()) { |
101 | ERR("lttng_ust_cancelstate_disable_push"); | |
20142124 MD |
102 | } |
103 | sigfillset(&sig_all_blocked); | |
104 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
105 | if (ret) { | |
106 | ERR("pthread_sigmask: %s", strerror(ret)); | |
107 | } | |
108 | if (!URCU_TLS(ust_perf_mutex_nest)++) { | |
109 | /* | |
110 | * Ensure the compiler don't move the store after the close() | |
111 | * call in case close() would be marked as leaf. | |
112 | */ | |
113 | cmm_barrier(); | |
114 | pthread_mutex_lock(&ust_perf_mutex); | |
20142124 MD |
115 | } |
116 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
117 | if (ret) { | |
118 | ERR("pthread_sigmask: %s", strerror(ret)); | |
119 | } | |
120 | } | |
121 | ||
122 | void lttng_perf_unlock(void) | |
123 | { | |
124 | sigset_t sig_all_blocked, orig_mask; | |
59e57035 | 125 | int ret; |
20142124 MD |
126 | |
127 | sigfillset(&sig_all_blocked); | |
128 | ret = pthread_sigmask(SIG_SETMASK, &sig_all_blocked, &orig_mask); | |
129 | if (ret) { | |
130 | ERR("pthread_sigmask: %s", strerror(ret)); | |
131 | } | |
132 | /* | |
133 | * Ensure the compiler don't move the store before the close() | |
134 | * call, in case close() would be marked as leaf. | |
135 | */ | |
136 | cmm_barrier(); | |
137 | if (!--URCU_TLS(ust_perf_mutex_nest)) { | |
20142124 MD |
138 | pthread_mutex_unlock(&ust_perf_mutex); |
139 | } | |
140 | ret = pthread_sigmask(SIG_SETMASK, &orig_mask, NULL); | |
141 | if (ret) { | |
142 | ERR("pthread_sigmask: %s", strerror(ret)); | |
143 | } | |
59e57035 MD |
144 | if (lttng_ust_cancelstate_disable_pop()) { |
145 | ERR("lttng_ust_cancelstate_disable_pop"); | |
20142124 MD |
146 | } |
147 | } | |
148 | ||
d58d1454 | 149 | static |
4e48b5d2 | 150 | size_t perf_counter_get_size(void *priv __attribute__((unused)), |
b2e37d27 | 151 | struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)), |
2208d8b5 | 152 | size_t offset) |
d58d1454 MD |
153 | { |
154 | size_t size = 0; | |
155 | ||
b5457df5 | 156 | size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(uint64_t)); |
d58d1454 MD |
157 | size += sizeof(uint64_t); |
158 | return size; | |
159 | } | |
160 | ||
a3a8d943 MD |
161 | static |
162 | uint64_t read_perf_counter_syscall( | |
163 | struct lttng_perf_counter_thread_field *thread_field) | |
164 | { | |
165 | uint64_t count; | |
166 | ||
167 | if (caa_unlikely(thread_field->fd < 0)) | |
168 | return 0; | |
169 | ||
170 | if (caa_unlikely(read(thread_field->fd, &count, sizeof(count)) | |
171 | < sizeof(count))) | |
172 | return 0; | |
173 | ||
174 | return count; | |
175 | } | |
176 | ||
2eba8e39 | 177 | #if defined(LTTNG_UST_ARCH_X86) |
d58d1454 MD |
178 | |
179 | static | |
180 | uint64_t rdpmc(unsigned int counter) | |
181 | { | |
182 | unsigned int low, high; | |
183 | ||
184 | asm volatile("rdpmc" : "=a" (low), "=d" (high) : "c" (counter)); | |
185 | ||
186 | return low | ((uint64_t) high) << 32; | |
187 | } | |
188 | ||
77d7fa98 MD |
189 | static |
190 | bool has_rdpmc(struct perf_event_mmap_page *pc) | |
191 | { | |
192 | if (caa_unlikely(!pc->cap_bit0_is_deprecated)) | |
193 | return false; | |
194 | /* Since Linux kernel 3.12. */ | |
195 | return pc->cap_user_rdpmc; | |
196 | } | |
197 | ||
d58d1454 | 198 | static |
a3a8d943 | 199 | uint64_t arch_read_perf_counter( |
d286ad50 | 200 | struct lttng_perf_counter_thread_field *thread_field) |
d58d1454 MD |
201 | { |
202 | uint32_t seq, idx; | |
203 | uint64_t count; | |
d286ad50 | 204 | struct perf_event_mmap_page *pc = thread_field->pc; |
d58d1454 MD |
205 | |
206 | if (caa_unlikely(!pc)) | |
207 | return 0; | |
208 | ||
209 | do { | |
210 | seq = CMM_LOAD_SHARED(pc->lock); | |
211 | cmm_barrier(); | |
212 | ||
213 | idx = pc->index; | |
77d7fa98 | 214 | if (caa_likely(has_rdpmc(pc) && idx)) { |
4f58f54f MD |
215 | int64_t pmcval; |
216 | ||
217 | pmcval = rdpmc(idx - 1); | |
218 | /* Sign-extend the pmc register result. */ | |
219 | pmcval <<= 64 - pc->pmc_width; | |
220 | pmcval >>= 64 - pc->pmc_width; | |
221 | count = pc->offset + pmcval; | |
222 | } else { | |
a3a8d943 MD |
223 | /* Fall-back on system call if rdpmc cannot be used. */ |
224 | return read_perf_counter_syscall(thread_field); | |
4f58f54f | 225 | } |
d58d1454 MD |
226 | cmm_barrier(); |
227 | } while (CMM_LOAD_SHARED(pc->lock) != seq); | |
228 | ||
229 | return count; | |
230 | } | |
231 | ||
d286ad50 | 232 | static |
a3a8d943 | 233 | int arch_perf_keep_fd(struct lttng_perf_counter_thread_field *thread_field) |
d286ad50 | 234 | { |
a3a8d943 | 235 | struct perf_event_mmap_page *pc = thread_field->pc; |
d286ad50 | 236 | |
a3a8d943 | 237 | if (!pc) |
d286ad50 | 238 | return 0; |
77d7fa98 | 239 | return !has_rdpmc(pc); |
a3a8d943 | 240 | } |
d286ad50 | 241 | |
a3a8d943 | 242 | #else |
d286ad50 | 243 | |
a3a8d943 MD |
244 | /* Generic (slow) implementation using a read system call. */ |
245 | static | |
246 | uint64_t arch_read_perf_counter( | |
247 | struct lttng_perf_counter_thread_field *thread_field) | |
248 | { | |
249 | return read_perf_counter_syscall(thread_field); | |
d286ad50 JD |
250 | } |
251 | ||
a3a8d943 | 252 | static |
c494c0f1 | 253 | int arch_perf_keep_fd(struct lttng_perf_counter_thread_field *thread_field __attribute__((unused))) |
a3a8d943 MD |
254 | { |
255 | return 1; | |
256 | } | |
d286ad50 | 257 | |
a3a8d943 | 258 | #endif |
d286ad50 | 259 | |
d58d1454 MD |
260 | static |
261 | int sys_perf_event_open(struct perf_event_attr *attr, | |
262 | pid_t pid, int cpu, int group_fd, | |
263 | unsigned long flags) | |
264 | { | |
265 | return syscall(SYS_perf_event_open, attr, pid, cpu, | |
266 | group_fd, flags); | |
267 | } | |
268 | ||
269 | static | |
b9389e6e | 270 | int open_perf_fd(struct perf_event_attr *attr) |
d58d1454 | 271 | { |
b9389e6e | 272 | int fd; |
d58d1454 MD |
273 | |
274 | fd = sys_perf_event_open(attr, 0, -1, -1, 0); | |
275 | if (fd < 0) | |
b9389e6e JD |
276 | return -1; |
277 | ||
278 | return fd; | |
279 | } | |
280 | ||
d286ad50 JD |
281 | static |
282 | void close_perf_fd(int fd) | |
283 | { | |
284 | int ret; | |
285 | ||
286 | if (fd < 0) | |
287 | return; | |
288 | ||
289 | ret = close(fd); | |
290 | if (ret) { | |
291 | perror("Error closing LTTng-UST perf memory mapping FD"); | |
292 | } | |
293 | } | |
294 | ||
77d7fa98 | 295 | static void setup_perf(struct lttng_perf_counter_thread_field *thread_field) |
b9389e6e JD |
296 | { |
297 | void *perf_addr; | |
d58d1454 MD |
298 | |
299 | perf_addr = mmap(NULL, sizeof(struct perf_event_mmap_page), | |
b9389e6e | 300 | PROT_READ, MAP_SHARED, thread_field->fd, 0); |
d58d1454 | 301 | if (perf_addr == MAP_FAILED) |
b9389e6e | 302 | perf_addr = NULL; |
77d7fa98 | 303 | thread_field->pc = perf_addr; |
b9389e6e | 304 | |
a3a8d943 | 305 | if (!arch_perf_keep_fd(thread_field)) { |
b9389e6e JD |
306 | close_perf_fd(thread_field->fd); |
307 | thread_field->fd = -1; | |
6c2125af | 308 | } |
d58d1454 MD |
309 | } |
310 | ||
311 | static | |
312 | void unmap_perf_page(struct perf_event_mmap_page *pc) | |
313 | { | |
314 | int ret; | |
315 | ||
316 | if (!pc) | |
317 | return; | |
318 | ret = munmap(pc, sizeof(struct perf_event_mmap_page)); | |
319 | if (ret < 0) { | |
320 | PERROR("Error in munmap"); | |
321 | abort(); | |
322 | } | |
323 | } | |
324 | ||
325 | static | |
326 | struct lttng_perf_counter_thread *alloc_perf_counter_thread(void) | |
327 | { | |
328 | struct lttng_perf_counter_thread *perf_thread; | |
329 | sigset_t newmask, oldmask; | |
330 | int ret; | |
331 | ||
332 | ret = sigfillset(&newmask); | |
333 | if (ret) | |
334 | abort(); | |
335 | ret = pthread_sigmask(SIG_BLOCK, &newmask, &oldmask); | |
336 | if (ret) | |
337 | abort(); | |
338 | /* Check again with signals disabled */ | |
339 | perf_thread = pthread_getspecific(perf_counter_key); | |
340 | if (perf_thread) | |
341 | goto skip; | |
342 | perf_thread = zmalloc(sizeof(*perf_thread)); | |
343 | if (!perf_thread) | |
344 | abort(); | |
345 | CDS_INIT_LIST_HEAD(&perf_thread->rcu_field_list); | |
346 | ret = pthread_setspecific(perf_counter_key, perf_thread); | |
347 | if (ret) | |
348 | abort(); | |
349 | skip: | |
350 | ret = pthread_sigmask(SIG_SETMASK, &oldmask, NULL); | |
351 | if (ret) | |
352 | abort(); | |
353 | return perf_thread; | |
354 | } | |
355 | ||
356 | static | |
357 | struct lttng_perf_counter_thread_field * | |
358 | add_thread_field(struct lttng_perf_counter_field *perf_field, | |
359 | struct lttng_perf_counter_thread *perf_thread) | |
360 | { | |
361 | struct lttng_perf_counter_thread_field *thread_field; | |
362 | sigset_t newmask, oldmask; | |
363 | int ret; | |
364 | ||
365 | ret = sigfillset(&newmask); | |
366 | if (ret) | |
367 | abort(); | |
368 | ret = pthread_sigmask(SIG_BLOCK, &newmask, &oldmask); | |
369 | if (ret) | |
370 | abort(); | |
371 | /* Check again with signals disabled */ | |
372 | cds_list_for_each_entry_rcu(thread_field, &perf_thread->rcu_field_list, | |
373 | rcu_field_node) { | |
374 | if (thread_field->field == perf_field) | |
375 | goto skip; | |
376 | } | |
377 | thread_field = zmalloc(sizeof(*thread_field)); | |
378 | if (!thread_field) | |
379 | abort(); | |
380 | thread_field->field = perf_field; | |
b9389e6e JD |
381 | thread_field->fd = open_perf_fd(&perf_field->attr); |
382 | if (thread_field->fd >= 0) | |
77d7fa98 | 383 | setup_perf(thread_field); |
b9389e6e JD |
384 | /* |
385 | * Note: thread_field->pc can be NULL if setup_perf() fails. | |
386 | * Also, thread_field->fd can be -1 if open_perf_fd() fails. | |
387 | */ | |
20142124 | 388 | lttng_perf_lock(); |
d58d1454 MD |
389 | cds_list_add_rcu(&thread_field->rcu_field_node, |
390 | &perf_thread->rcu_field_list); | |
391 | cds_list_add(&thread_field->thread_field_node, | |
392 | &perf_field->thread_field_list); | |
20142124 | 393 | lttng_perf_unlock(); |
d58d1454 MD |
394 | skip: |
395 | ret = pthread_sigmask(SIG_SETMASK, &oldmask, NULL); | |
396 | if (ret) | |
397 | abort(); | |
398 | return thread_field; | |
399 | } | |
400 | ||
401 | static | |
402 | struct lttng_perf_counter_thread_field * | |
403 | get_thread_field(struct lttng_perf_counter_field *field) | |
404 | { | |
405 | struct lttng_perf_counter_thread *perf_thread; | |
406 | struct lttng_perf_counter_thread_field *thread_field; | |
407 | ||
408 | perf_thread = pthread_getspecific(perf_counter_key); | |
409 | if (!perf_thread) | |
410 | perf_thread = alloc_perf_counter_thread(); | |
411 | cds_list_for_each_entry_rcu(thread_field, &perf_thread->rcu_field_list, | |
412 | rcu_field_node) { | |
413 | if (thread_field->field == field) | |
414 | return thread_field; | |
415 | } | |
416 | /* perf_counter_thread_field not found, need to add one */ | |
417 | return add_thread_field(field, perf_thread); | |
418 | } | |
419 | ||
420 | static | |
4e48b5d2 | 421 | uint64_t wrapper_perf_counter_read(void *priv) |
d58d1454 MD |
422 | { |
423 | struct lttng_perf_counter_field *perf_field; | |
424 | struct lttng_perf_counter_thread_field *perf_thread_field; | |
425 | ||
4e48b5d2 | 426 | perf_field = (struct lttng_perf_counter_field *) priv; |
d58d1454 | 427 | perf_thread_field = get_thread_field(perf_field); |
a3a8d943 | 428 | return arch_read_perf_counter(perf_thread_field); |
d58d1454 MD |
429 | } |
430 | ||
431 | static | |
4e48b5d2 | 432 | void perf_counter_record(void *priv, |
b2e37d27 MD |
433 | struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)), |
434 | struct lttng_ust_ring_buffer_ctx *ctx, | |
435 | struct lttng_ust_channel_buffer *chan) | |
d58d1454 MD |
436 | { |
437 | uint64_t value; | |
438 | ||
4e48b5d2 | 439 | value = wrapper_perf_counter_read(priv); |
8936b6c0 | 440 | chan->ops->event_write(ctx, &value, sizeof(value), lttng_ust_rb_alignof(value)); |
d58d1454 MD |
441 | } |
442 | ||
443 | static | |
4e48b5d2 | 444 | void perf_counter_get_value(void *priv, |
b2e37d27 | 445 | struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)), |
daacdbfc | 446 | struct lttng_ust_ctx_value *value) |
d58d1454 | 447 | { |
b2e37d27 | 448 | value->u.u64 = wrapper_perf_counter_read(priv); |
d58d1454 MD |
449 | } |
450 | ||
20142124 | 451 | /* Called with perf lock held */ |
d58d1454 MD |
452 | static |
453 | void lttng_destroy_perf_thread_field( | |
454 | struct lttng_perf_counter_thread_field *thread_field) | |
455 | { | |
b9389e6e | 456 | close_perf_fd(thread_field->fd); |
d58d1454 MD |
457 | unmap_perf_page(thread_field->pc); |
458 | cds_list_del_rcu(&thread_field->rcu_field_node); | |
459 | cds_list_del(&thread_field->thread_field_node); | |
460 | free(thread_field); | |
461 | } | |
462 | ||
463 | static | |
464 | void lttng_destroy_perf_thread_key(void *_key) | |
465 | { | |
466 | struct lttng_perf_counter_thread *perf_thread = _key; | |
467 | struct lttng_perf_counter_thread_field *pos, *p; | |
468 | ||
20142124 | 469 | lttng_perf_lock(); |
d58d1454 MD |
470 | cds_list_for_each_entry_safe(pos, p, &perf_thread->rcu_field_list, |
471 | rcu_field_node) | |
472 | lttng_destroy_perf_thread_field(pos); | |
20142124 | 473 | lttng_perf_unlock(); |
d58d1454 MD |
474 | free(perf_thread); |
475 | } | |
476 | ||
477 | /* Called with UST lock held */ | |
478 | static | |
4e48b5d2 | 479 | void lttng_destroy_perf_counter_ctx_field(void *priv) |
d58d1454 MD |
480 | { |
481 | struct lttng_perf_counter_field *perf_field; | |
482 | struct lttng_perf_counter_thread_field *pos, *p; | |
483 | ||
4e48b5d2 MD |
484 | perf_field = (struct lttng_perf_counter_field *) priv; |
485 | free(perf_field->name); | |
d58d1454 MD |
486 | /* |
487 | * This put is performed when no threads can concurrently | |
488 | * perform a "get" concurrently, thanks to urcu-bp grace | |
20142124 MD |
489 | * period. Holding the lttng perf lock protects against |
490 | * concurrent modification of the per-thread thread field | |
491 | * list. | |
d58d1454 | 492 | */ |
20142124 | 493 | lttng_perf_lock(); |
d58d1454 MD |
494 | cds_list_for_each_entry_safe(pos, p, &perf_field->thread_field_list, |
495 | thread_field_node) | |
496 | lttng_destroy_perf_thread_field(pos); | |
20142124 | 497 | lttng_perf_unlock(); |
f72cd4d9 | 498 | free(perf_field->event_field); |
d58d1454 MD |
499 | free(perf_field); |
500 | } | |
501 | ||
2eba8e39 | 502 | #ifdef LTTNG_UST_ARCH_ARMV7 |
d286ad50 JD |
503 | |
504 | static | |
505 | int perf_get_exclude_kernel(void) | |
506 | { | |
507 | return 0; | |
508 | } | |
509 | ||
2eba8e39 | 510 | #else /* LTTNG_UST_ARCH_ARMV7 */ |
d286ad50 JD |
511 | |
512 | static | |
513 | int perf_get_exclude_kernel(void) | |
514 | { | |
515 | return 1; | |
516 | } | |
517 | ||
2eba8e39 | 518 | #endif /* LTTNG_UST_ARCH_ARMV7 */ |
d286ad50 | 519 | |
4e48b5d2 MD |
520 | static const struct lttng_ust_type_common *ust_type = |
521 | lttng_ust_static_type_integer(sizeof(uint64_t) * CHAR_BIT, | |
522 | lttng_ust_rb_alignof(uint64_t) * CHAR_BIT, | |
523 | lttng_ust_is_signed_type(uint64_t), | |
baa8acf3 | 524 | LTTNG_UST_BYTE_ORDER, 10); |
4e48b5d2 | 525 | |
d58d1454 MD |
526 | /* Called with UST lock held */ |
527 | int lttng_add_perf_counter_to_ctx(uint32_t type, | |
528 | uint64_t config, | |
529 | const char *name, | |
daacdbfc | 530 | struct lttng_ust_ctx **ctx) |
d58d1454 | 531 | { |
4e48b5d2 MD |
532 | struct lttng_ust_ctx_field ctx_field; |
533 | struct lttng_ust_event_field *event_field; | |
d58d1454 | 534 | struct lttng_perf_counter_field *perf_field; |
d58d1454 MD |
535 | char *name_alloc; |
536 | int ret; | |
537 | ||
4e48b5d2 MD |
538 | if (lttng_find_context(*ctx, name)) { |
539 | ret = -EEXIST; | |
540 | goto find_error; | |
541 | } | |
d58d1454 MD |
542 | name_alloc = strdup(name); |
543 | if (!name_alloc) { | |
544 | ret = -ENOMEM; | |
545 | goto name_alloc_error; | |
546 | } | |
4e48b5d2 MD |
547 | event_field = zmalloc(sizeof(*event_field)); |
548 | if (!event_field) { | |
549 | ret = -ENOMEM; | |
550 | goto event_field_alloc_error; | |
551 | } | |
552 | event_field->name = name_alloc; | |
553 | event_field->type = ust_type; | |
554 | ||
d58d1454 MD |
555 | perf_field = zmalloc(sizeof(*perf_field)); |
556 | if (!perf_field) { | |
557 | ret = -ENOMEM; | |
558 | goto perf_field_alloc_error; | |
559 | } | |
d58d1454 MD |
560 | perf_field->attr.type = type; |
561 | perf_field->attr.config = config; | |
d286ad50 | 562 | perf_field->attr.exclude_kernel = perf_get_exclude_kernel(); |
d58d1454 | 563 | CDS_INIT_LIST_HEAD(&perf_field->thread_field_list); |
4e48b5d2 | 564 | perf_field->name = name_alloc; |
f72cd4d9 | 565 | perf_field->event_field = event_field; |
d58d1454 MD |
566 | |
567 | /* Ensure that this perf counter can be used in this process. */ | |
b9389e6e JD |
568 | ret = open_perf_fd(&perf_field->attr); |
569 | if (ret < 0) { | |
d58d1454 MD |
570 | ret = -ENODEV; |
571 | goto setup_error; | |
572 | } | |
b9389e6e | 573 | close_perf_fd(ret); |
d58d1454 | 574 | |
4e48b5d2 MD |
575 | ctx_field.event_field = event_field; |
576 | ctx_field.get_size = perf_counter_get_size; | |
577 | ctx_field.record = perf_counter_record; | |
578 | ctx_field.get_value = perf_counter_get_value; | |
579 | ctx_field.destroy = lttng_destroy_perf_counter_ctx_field; | |
580 | ctx_field.priv = perf_field; | |
d58d1454 | 581 | |
4e48b5d2 MD |
582 | ret = lttng_ust_context_append(ctx, &ctx_field); |
583 | if (ret) { | |
584 | ret = -ENOMEM; | |
585 | goto append_context_error; | |
586 | } | |
d58d1454 MD |
587 | return 0; |
588 | ||
d58d1454 | 589 | append_context_error: |
4e48b5d2 | 590 | setup_error: |
d58d1454 MD |
591 | free(perf_field); |
592 | perf_field_alloc_error: | |
4e48b5d2 MD |
593 | free(event_field); |
594 | event_field_alloc_error: | |
d58d1454 MD |
595 | free(name_alloc); |
596 | name_alloc_error: | |
4e48b5d2 | 597 | find_error: |
d58d1454 MD |
598 | return ret; |
599 | } | |
600 | ||
601 | int lttng_perf_counter_init(void) | |
602 | { | |
603 | int ret; | |
604 | ||
605 | ret = pthread_key_create(&perf_counter_key, | |
606 | lttng_destroy_perf_thread_key); | |
607 | if (ret) | |
608 | ret = -ret; | |
609 | return ret; | |
610 | } | |
611 | ||
612 | void lttng_perf_counter_exit(void) | |
613 | { | |
614 | int ret; | |
615 | ||
616 | ret = pthread_key_delete(perf_counter_key); | |
617 | if (ret) { | |
618 | errno = ret; | |
619 | PERROR("Error in pthread_key_delete"); | |
620 | } | |
621 | } |