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0376e7b2 PM |
1 | #ifndef _URCU_DEFER_IMPL_H |
2 | #define _URCU_DEFER_IMPL_H | |
3 | ||
786ee85b | 4 | /* |
0376e7b2 PM |
5 | * urcu-defer-impl.h |
6 | * | |
7 | * Userspace RCU header - memory reclamation. | |
786ee85b | 8 | * |
0376e7b2 PM |
9 | * TO BE INCLUDED ONLY FROM URCU LIBRARY CODE. See urcu-defer.h for linking |
10 | * dynamically with the userspace rcu reclamation library. | |
786ee85b | 11 | * |
6982d6d7 | 12 | * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
0376e7b2 | 13 | * Copyright (c) 2009 Paul E. McKenney, IBM Corporation. |
786ee85b MD |
14 | * |
15 | * This library is free software; you can redistribute it and/or | |
16 | * modify it under the terms of the GNU Lesser General Public | |
17 | * License as published by the Free Software Foundation; either | |
18 | * version 2.1 of the License, or (at your option) any later version. | |
19 | * | |
20 | * This library is distributed in the hope that it will be useful, | |
21 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
22 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
23 | * Lesser General Public License for more details. | |
24 | * | |
25 | * You should have received a copy of the GNU Lesser General Public | |
26 | * License along with this library; if not, write to the Free Software | |
27 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
0376e7b2 PM |
28 | * |
29 | * IBM's contributions to this file may be relicensed under LGPLv2 or later. | |
786ee85b MD |
30 | */ |
31 | ||
0376e7b2 | 32 | #include <stdlib.h> |
786ee85b | 33 | #include <pthread.h> |
0376e7b2 | 34 | #include <stdio.h> |
786ee85b MD |
35 | #include <signal.h> |
36 | #include <assert.h> | |
786ee85b MD |
37 | #include <string.h> |
38 | #include <errno.h> | |
39 | #include <poll.h> | |
4ce9e4f2 | 40 | #include <sys/time.h> |
4ce9e4f2 | 41 | #include <unistd.h> |
6d841bc2 | 42 | #include <stdint.h> |
786ee85b | 43 | |
41849996 | 44 | #include "urcu/futex.h" |
0376e7b2 PM |
45 | |
46 | #include <urcu/compiler.h> | |
47 | #include <urcu/arch.h> | |
a2e7bf9c | 48 | #include <urcu/uatomic.h> |
0376e7b2 PM |
49 | #include <urcu/list.h> |
50 | #include <urcu/system.h> | |
bd252a04 | 51 | #include <urcu/tls-compat.h> |
0376e7b2 PM |
52 | |
53 | /* | |
54 | * Number of entries in the per-thread defer queue. Must be power of 2. | |
55 | */ | |
56 | #define DEFER_QUEUE_SIZE (1 << 12) | |
57 | #define DEFER_QUEUE_MASK (DEFER_QUEUE_SIZE - 1) | |
58 | ||
59 | /* | |
60 | * Typically, data is aligned at least on the architecture size. | |
61 | * Use lowest bit to indicate that the current callback is changing. | |
62 | * Assumes that (void *)-2L is not used often. Used to encode non-aligned | |
63 | * functions and non-aligned data using extra space. | |
64 | * We encode the (void *)-2L fct as: -2L, fct, data. | |
2ef1bfb2 LJ |
65 | * We encode the (void *)-2L data as either: |
66 | * fct | DQ_FCT_BIT, data (if fct is aligned), or | |
67 | * -2L, fct, data (if fct is not aligned). | |
0376e7b2 PM |
68 | * Here, DQ_FCT_MARK == ~DQ_FCT_BIT. Required for the test order. |
69 | */ | |
70 | #define DQ_FCT_BIT (1 << 0) | |
71 | #define DQ_IS_FCT_BIT(x) ((unsigned long)(x) & DQ_FCT_BIT) | |
72 | #define DQ_SET_FCT_BIT(x) \ | |
73 | (x = (void *)((unsigned long)(x) | DQ_FCT_BIT)) | |
74 | #define DQ_CLEAR_FCT_BIT(x) \ | |
75 | (x = (void *)((unsigned long)(x) & ~DQ_FCT_BIT)) | |
76 | #define DQ_FCT_MARK ((void *)(~DQ_FCT_BIT)) | |
77 | ||
78 | /* | |
79 | * This code section can only be included in LGPL 2.1 compatible source code. | |
80 | * See below for the function call wrappers which can be used in code meant to | |
81 | * be only linked with the Userspace RCU library. This comes with a small | |
82 | * performance degradation on the read-side due to the added function calls. | |
83 | * This is required to permit relinking with newer versions of the library. | |
84 | */ | |
85 | ||
86 | #ifdef DEBUG_RCU | |
87 | #define rcu_assert(args...) assert(args) | |
88 | #else | |
89 | #define rcu_assert(args...) | |
90 | #endif | |
91 | ||
92 | /* | |
93 | * defer queue. | |
94 | * Contains pointers. Encoded to save space when same callback is often used. | |
95 | * When looking up the next item: | |
96 | * - if DQ_FCT_BIT is set, set the current callback to DQ_CLEAR_FCT_BIT(ptr) | |
97 | * - next element contains pointer to data. | |
98 | * - else if item == DQ_FCT_MARK | |
99 | * - set the current callback to next element ptr | |
100 | * - following next element contains pointer to data. | |
101 | * - else current element contains data | |
102 | */ | |
103 | struct defer_queue { | |
104 | unsigned long head; /* add element at head */ | |
105 | void *last_fct_in; /* last fct pointer encoded */ | |
106 | unsigned long tail; /* next element to remove at tail */ | |
107 | void *last_fct_out; /* last fct pointer encoded */ | |
108 | void **q; | |
109 | /* registry information */ | |
110 | unsigned long last_head; | |
111 | struct cds_list_head list; /* list of thread queues */ | |
112 | }; | |
113 | ||
786ee85b MD |
114 | /* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */ |
115 | #include "urcu-defer.h" | |
116 | ||
02be5561 | 117 | void __attribute__((destructor)) rcu_defer_exit(void); |
786ee85b MD |
118 | |
119 | extern void synchronize_rcu(void); | |
120 | ||
121 | /* | |
02be5561 | 122 | * rcu_defer_mutex nests inside defer_thread_mutex. |
786ee85b | 123 | */ |
02be5561 | 124 | static pthread_mutex_t rcu_defer_mutex = PTHREAD_MUTEX_INITIALIZER; |
786ee85b MD |
125 | static pthread_mutex_t defer_thread_mutex = PTHREAD_MUTEX_INITIALIZER; |
126 | ||
6d841bc2 | 127 | static int32_t defer_thread_futex; |
d7ff6cee | 128 | static int32_t defer_thread_stop; |
4ce9e4f2 | 129 | |
786ee85b MD |
130 | /* |
131 | * Written to only by each individual deferer. Read by both the deferer and | |
132 | * the reclamation tread. | |
133 | */ | |
bd252a04 | 134 | static DEFINE_URCU_TLS(struct defer_queue, defer_queue); |
0376e7b2 | 135 | static CDS_LIST_HEAD(registry_defer); |
786ee85b | 136 | static pthread_t tid_defer; |
4ce9e4f2 | 137 | |
0376e7b2 | 138 | static void mutex_lock_defer(pthread_mutex_t *mutex) |
786ee85b MD |
139 | { |
140 | int ret; | |
141 | ||
142 | #ifndef DISTRUST_SIGNALS_EXTREME | |
143 | ret = pthread_mutex_lock(mutex); | |
144 | if (ret) { | |
145 | perror("Error in pthread mutex lock"); | |
146 | exit(-1); | |
147 | } | |
148 | #else /* #ifndef DISTRUST_SIGNALS_EXTREME */ | |
149 | while ((ret = pthread_mutex_trylock(mutex)) != 0) { | |
150 | if (ret != EBUSY && ret != EINTR) { | |
151 | printf("ret = %d, errno = %d\n", ret, errno); | |
152 | perror("Error in pthread mutex lock"); | |
153 | exit(-1); | |
154 | } | |
155 | poll(NULL,0,10); | |
156 | } | |
157 | #endif /* #else #ifndef DISTRUST_SIGNALS_EXTREME */ | |
158 | } | |
159 | ||
04eb9c4f MD |
160 | /* |
161 | * Wake-up any waiting defer thread. Called from many concurrent threads. | |
162 | */ | |
163 | static void wake_up_defer(void) | |
164 | { | |
a0b7f7ea | 165 | if (caa_unlikely(uatomic_read(&defer_thread_futex) == -1)) { |
ec4e58a3 | 166 | uatomic_set(&defer_thread_futex, 0); |
0854ccff | 167 | futex_noasync(&defer_thread_futex, FUTEX_WAKE, 1, |
04eb9c4f MD |
168 | NULL, NULL, 0); |
169 | } | |
170 | } | |
171 | ||
172 | static unsigned long rcu_defer_num_callbacks(void) | |
173 | { | |
174 | unsigned long num_items = 0, head; | |
dbc6128f | 175 | struct defer_queue *index; |
04eb9c4f | 176 | |
0376e7b2 PM |
177 | mutex_lock_defer(&rcu_defer_mutex); |
178 | cds_list_for_each_entry(index, ®istry_defer, list) { | |
6cf3827c | 179 | head = CMM_LOAD_SHARED(index->head); |
dbc6128f | 180 | num_items += head - index->tail; |
04eb9c4f | 181 | } |
6abb4bd5 | 182 | mutex_unlock(&rcu_defer_mutex); |
04eb9c4f MD |
183 | return num_items; |
184 | } | |
185 | ||
186 | /* | |
187 | * Defer thread waiting. Single thread. | |
188 | */ | |
189 | static void wait_defer(void) | |
190 | { | |
ec4e58a3 | 191 | uatomic_dec(&defer_thread_futex); |
d7ff6cee MD |
192 | /* Write futex before read queue */ |
193 | /* Write futex before read defer_thread_stop */ | |
194 | cmm_smp_mb(); | |
195 | if (_CMM_LOAD_SHARED(defer_thread_stop)) { | |
196 | uatomic_set(&defer_thread_futex, 0); | |
197 | pthread_exit(0); | |
198 | } | |
04eb9c4f | 199 | if (rcu_defer_num_callbacks()) { |
5481ddb3 | 200 | cmm_smp_mb(); /* Read queue before write futex */ |
04eb9c4f | 201 | /* Callbacks are queued, don't wait. */ |
ec4e58a3 | 202 | uatomic_set(&defer_thread_futex, 0); |
04eb9c4f | 203 | } else { |
5481ddb3 | 204 | cmm_smp_rmb(); /* Read queue before read futex */ |
ec4e58a3 | 205 | if (uatomic_read(&defer_thread_futex) == -1) |
0854ccff | 206 | futex_noasync(&defer_thread_futex, FUTEX_WAIT, -1, |
04eb9c4f MD |
207 | NULL, NULL, 0); |
208 | } | |
209 | } | |
210 | ||
786ee85b MD |
211 | /* |
212 | * Must be called after Q.S. is reached. | |
213 | */ | |
214 | static void rcu_defer_barrier_queue(struct defer_queue *queue, | |
804b4375 | 215 | unsigned long head) |
786ee85b MD |
216 | { |
217 | unsigned long i; | |
804b4375 MD |
218 | void (*fct)(void *p); |
219 | void *p; | |
786ee85b MD |
220 | |
221 | /* | |
222 | * Tail is only modified when lock is held. | |
223 | * Head is only modified by owner thread. | |
224 | */ | |
225 | ||
804b4375 | 226 | for (i = queue->tail; i != head;) { |
5481ddb3 | 227 | cmm_smp_rmb(); /* read head before q[]. */ |
6cf3827c | 228 | p = CMM_LOAD_SHARED(queue->q[i++ & DEFER_QUEUE_MASK]); |
a0b7f7ea | 229 | if (caa_unlikely(DQ_IS_FCT_BIT(p))) { |
804b4375 MD |
230 | DQ_CLEAR_FCT_BIT(p); |
231 | queue->last_fct_out = p; | |
6cf3827c | 232 | p = CMM_LOAD_SHARED(queue->q[i++ & DEFER_QUEUE_MASK]); |
a0b7f7ea | 233 | } else if (caa_unlikely(p == DQ_FCT_MARK)) { |
6cf3827c | 234 | p = CMM_LOAD_SHARED(queue->q[i++ & DEFER_QUEUE_MASK]); |
804b4375 | 235 | queue->last_fct_out = p; |
6cf3827c | 236 | p = CMM_LOAD_SHARED(queue->q[i++ & DEFER_QUEUE_MASK]); |
29cdb8d8 | 237 | } |
804b4375 | 238 | fct = queue->last_fct_out; |
804b4375 | 239 | fct(p); |
786ee85b | 240 | } |
5481ddb3 | 241 | cmm_smp_mb(); /* push tail after having used q[] */ |
6cf3827c | 242 | CMM_STORE_SHARED(queue->tail, i); |
786ee85b MD |
243 | } |
244 | ||
245 | static void _rcu_defer_barrier_thread(void) | |
246 | { | |
0d0e6c21 | 247 | unsigned long head, num_items; |
786ee85b | 248 | |
bd252a04 MD |
249 | head = URCU_TLS(defer_queue).head; |
250 | num_items = head - URCU_TLS(defer_queue).tail; | |
a0b7f7ea | 251 | if (caa_unlikely(!num_items)) |
0d0e6c21 | 252 | return; |
786ee85b | 253 | synchronize_rcu(); |
bd252a04 | 254 | rcu_defer_barrier_queue(&URCU_TLS(defer_queue), head); |
786ee85b MD |
255 | } |
256 | ||
786ee85b MD |
257 | void rcu_defer_barrier_thread(void) |
258 | { | |
0376e7b2 | 259 | mutex_lock_defer(&rcu_defer_mutex); |
786ee85b | 260 | _rcu_defer_barrier_thread(); |
6abb4bd5 | 261 | mutex_unlock(&rcu_defer_mutex); |
786ee85b MD |
262 | } |
263 | ||
0d0e6c21 MD |
264 | /* |
265 | * rcu_defer_barrier - Execute all queued rcu callbacks. | |
266 | * | |
267 | * Execute all RCU callbacks queued before rcu_defer_barrier() execution. | |
268 | * All callbacks queued on the local thread prior to a rcu_defer_barrier() call | |
269 | * are guaranteed to be executed. | |
270 | * Callbacks queued by other threads concurrently with rcu_defer_barrier() | |
271 | * execution are not guaranteed to be executed in the current batch (could | |
272 | * be left for the next batch). These callbacks queued by other threads are only | |
273 | * guaranteed to be executed if there is explicit synchronization between | |
274 | * the thread adding to the queue and the thread issuing the defer_barrier call. | |
275 | */ | |
276 | ||
786ee85b MD |
277 | void rcu_defer_barrier(void) |
278 | { | |
dbc6128f | 279 | struct defer_queue *index; |
0d0e6c21 | 280 | unsigned long num_items = 0; |
786ee85b | 281 | |
0376e7b2 | 282 | if (cds_list_empty(®istry_defer)) |
786ee85b MD |
283 | return; |
284 | ||
0376e7b2 PM |
285 | mutex_lock_defer(&rcu_defer_mutex); |
286 | cds_list_for_each_entry(index, ®istry_defer, list) { | |
6cf3827c | 287 | index->last_head = CMM_LOAD_SHARED(index->head); |
dbc6128f | 288 | num_items += index->last_head - index->tail; |
0d0e6c21 | 289 | } |
a0b7f7ea | 290 | if (caa_likely(!num_items)) { |
0d0e6c21 MD |
291 | /* |
292 | * We skip the grace period because there are no queued | |
293 | * callbacks to execute. | |
294 | */ | |
295 | goto end; | |
296 | } | |
786ee85b | 297 | synchronize_rcu(); |
0376e7b2 | 298 | cds_list_for_each_entry(index, ®istry_defer, list) |
dbc6128f | 299 | rcu_defer_barrier_queue(index, index->last_head); |
0d0e6c21 | 300 | end: |
6abb4bd5 | 301 | mutex_unlock(&rcu_defer_mutex); |
786ee85b MD |
302 | } |
303 | ||
2c22932b | 304 | /* |
b4f313b7 | 305 | * _defer_rcu - Queue a RCU callback. |
2c22932b | 306 | */ |
3614f13c | 307 | void _defer_rcu(void (*fct)(void *p), void *p) |
2c22932b MD |
308 | { |
309 | unsigned long head, tail; | |
310 | ||
311 | /* | |
312 | * Head is only modified by ourself. Tail can be modified by reclamation | |
313 | * thread. | |
314 | */ | |
bd252a04 MD |
315 | head = URCU_TLS(defer_queue).head; |
316 | tail = CMM_LOAD_SHARED(URCU_TLS(defer_queue).tail); | |
2c22932b MD |
317 | |
318 | /* | |
ec8e44cf | 319 | * If queue is full, or reached threshold. Empty queue ourself. |
2c22932b MD |
320 | * Worse-case: must allow 2 supplementary entries for fct pointer. |
321 | */ | |
a0b7f7ea | 322 | if (caa_unlikely(head - tail >= DEFER_QUEUE_SIZE - 2)) { |
2c22932b MD |
323 | assert(head - tail <= DEFER_QUEUE_SIZE); |
324 | rcu_defer_barrier_thread(); | |
bd252a04 | 325 | assert(head - CMM_LOAD_SHARED(URCU_TLS(defer_queue).tail) == 0); |
2c22932b MD |
326 | } |
327 | ||
2ef1bfb2 LJ |
328 | /* |
329 | * Encode: | |
330 | * if the function is not changed and the data is aligned and it is | |
331 | * not the marker: | |
332 | * store the data | |
333 | * otherwise if the function is aligned and its not the marker: | |
334 | * store the function with DQ_FCT_BIT | |
335 | * store the data | |
336 | * otherwise: | |
337 | * store the marker (DQ_FCT_MARK) | |
338 | * store the function | |
339 | * store the data | |
340 | * | |
341 | * Decode: see the comments before 'struct defer_queue' | |
342 | * or the code in rcu_defer_barrier_queue(). | |
343 | */ | |
bd252a04 | 344 | if (caa_unlikely(URCU_TLS(defer_queue).last_fct_in != fct |
2ef1bfb2 LJ |
345 | || DQ_IS_FCT_BIT(p) |
346 | || p == DQ_FCT_MARK)) { | |
bd252a04 | 347 | URCU_TLS(defer_queue).last_fct_in = fct; |
a0b7f7ea | 348 | if (caa_unlikely(DQ_IS_FCT_BIT(fct) || fct == DQ_FCT_MARK)) { |
bd252a04 | 349 | _CMM_STORE_SHARED(URCU_TLS(defer_queue).q[head++ & DEFER_QUEUE_MASK], |
2c22932b | 350 | DQ_FCT_MARK); |
bd252a04 | 351 | _CMM_STORE_SHARED(URCU_TLS(defer_queue).q[head++ & DEFER_QUEUE_MASK], |
2c22932b MD |
352 | fct); |
353 | } else { | |
354 | DQ_SET_FCT_BIT(fct); | |
bd252a04 | 355 | _CMM_STORE_SHARED(URCU_TLS(defer_queue).q[head++ & DEFER_QUEUE_MASK], |
2c22932b MD |
356 | fct); |
357 | } | |
2c22932b | 358 | } |
bd252a04 | 359 | _CMM_STORE_SHARED(URCU_TLS(defer_queue).q[head++ & DEFER_QUEUE_MASK], p); |
5481ddb3 | 360 | cmm_smp_wmb(); /* Publish new pointer before head */ |
2c22932b | 361 | /* Write q[] before head. */ |
bd252a04 | 362 | CMM_STORE_SHARED(URCU_TLS(defer_queue).head, head); |
5481ddb3 | 363 | cmm_smp_mb(); /* Write queue head before read futex */ |
2c22932b MD |
364 | /* |
365 | * Wake-up any waiting defer thread. | |
366 | */ | |
367 | wake_up_defer(); | |
368 | } | |
369 | ||
786ee85b MD |
370 | void *thr_defer(void *args) |
371 | { | |
372 | for (;;) { | |
4ce9e4f2 MD |
373 | /* |
374 | * "Be green". Don't wake up the CPU if there is no RCU work | |
375 | * to perform whatsoever. Aims at saving laptop battery life by | |
376 | * leaving the processor in sleep state when idle. | |
377 | */ | |
4ce9e4f2 | 378 | wait_defer(); |
4ce9e4f2 | 379 | /* Sleeping after wait_defer to let many callbacks enqueue */ |
71df5ef4 | 380 | poll(NULL,0,100); /* wait for 100ms */ |
786ee85b MD |
381 | rcu_defer_barrier(); |
382 | } | |
383 | ||
384 | return NULL; | |
385 | } | |
386 | ||
387 | /* | |
388 | * library wrappers to be used by non-LGPL compatible source code. | |
389 | */ | |
390 | ||
3614f13c | 391 | void defer_rcu(void (*fct)(void *p), void *p) |
786ee85b | 392 | { |
3614f13c | 393 | _defer_rcu(fct, p); |
786ee85b MD |
394 | } |
395 | ||
786ee85b MD |
396 | static void start_defer_thread(void) |
397 | { | |
398 | int ret; | |
399 | ||
dbc6128f | 400 | ret = pthread_create(&tid_defer, NULL, thr_defer, NULL); |
786ee85b MD |
401 | assert(!ret); |
402 | } | |
403 | ||
404 | static void stop_defer_thread(void) | |
405 | { | |
406 | int ret; | |
407 | void *tret; | |
408 | ||
d7ff6cee MD |
409 | _CMM_STORE_SHARED(defer_thread_stop, 1); |
410 | /* Store defer_thread_stop before testing futex */ | |
411 | cmm_smp_mb(); | |
4ce9e4f2 | 412 | wake_up_defer(); |
d7ff6cee | 413 | |
786ee85b MD |
414 | ret = pthread_join(tid_defer, &tret); |
415 | assert(!ret); | |
d7ff6cee MD |
416 | |
417 | CMM_STORE_SHARED(defer_thread_stop, 0); | |
418 | /* defer thread should always exit when futex value is 0 */ | |
419 | assert(uatomic_read(&defer_thread_futex) == 0); | |
786ee85b MD |
420 | } |
421 | ||
7fdbbd61 | 422 | int rcu_defer_register_thread(void) |
786ee85b | 423 | { |
dbc6128f MD |
424 | int was_empty; |
425 | ||
bd252a04 MD |
426 | assert(URCU_TLS(defer_queue).last_head == 0); |
427 | assert(URCU_TLS(defer_queue).q == NULL); | |
428 | URCU_TLS(defer_queue).q = malloc(sizeof(void *) * DEFER_QUEUE_SIZE); | |
429 | if (!URCU_TLS(defer_queue).q) | |
7fdbbd61 | 430 | return -ENOMEM; |
786ee85b | 431 | |
0376e7b2 PM |
432 | mutex_lock_defer(&defer_thread_mutex); |
433 | mutex_lock_defer(&rcu_defer_mutex); | |
434 | was_empty = cds_list_empty(®istry_defer); | |
bd252a04 | 435 | cds_list_add(&URCU_TLS(defer_queue).list, ®istry_defer); |
6abb4bd5 | 436 | mutex_unlock(&rcu_defer_mutex); |
786ee85b | 437 | |
dbc6128f | 438 | if (was_empty) |
786ee85b | 439 | start_defer_thread(); |
6abb4bd5 | 440 | mutex_unlock(&defer_thread_mutex); |
7fdbbd61 | 441 | return 0; |
786ee85b MD |
442 | } |
443 | ||
444 | void rcu_defer_unregister_thread(void) | |
445 | { | |
dbc6128f | 446 | int is_empty; |
786ee85b | 447 | |
0376e7b2 PM |
448 | mutex_lock_defer(&defer_thread_mutex); |
449 | mutex_lock_defer(&rcu_defer_mutex); | |
bd252a04 | 450 | cds_list_del(&URCU_TLS(defer_queue).list); |
786ee85b | 451 | _rcu_defer_barrier_thread(); |
bd252a04 MD |
452 | free(URCU_TLS(defer_queue).q); |
453 | URCU_TLS(defer_queue).q = NULL; | |
0376e7b2 | 454 | is_empty = cds_list_empty(®istry_defer); |
6abb4bd5 | 455 | mutex_unlock(&rcu_defer_mutex); |
786ee85b | 456 | |
dbc6128f | 457 | if (is_empty) |
786ee85b | 458 | stop_defer_thread(); |
6abb4bd5 | 459 | mutex_unlock(&defer_thread_mutex); |
786ee85b MD |
460 | } |
461 | ||
02be5561 | 462 | void rcu_defer_exit(void) |
786ee85b | 463 | { |
0376e7b2 | 464 | assert(cds_list_empty(®istry_defer)); |
786ee85b | 465 | } |
0376e7b2 PM |
466 | |
467 | #endif /* _URCU_DEFER_IMPL_H */ |