4 * Userspace RCU library - example RCU-based lock-free queue
6 * Copyright February 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
7 * Copyright February 2010 - Paolo Bonzini <pbonzini@redhat.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
30 #include <sys/types.h>
36 #include <urcu/arch.h>
37 #include <urcu/assert.h>
38 #include <urcu/tls-compat.h>
39 #include "thread-id.h"
41 /* hardcoded number of CPUs */
44 #ifndef DYNAMIC_LINK_TEST
50 static volatile int test_go
, test_stop
;
52 static unsigned long rduration
;
54 static unsigned long duration
;
56 /* read-side C.S. duration, in loops */
57 static unsigned long wdelay
;
59 static inline void loop_sleep(unsigned long loops
)
65 static int verbose_mode
;
67 #define printf_verbose(fmt, args...) \
73 static unsigned int cpu_affinities
[NR_CPUS
];
74 static unsigned int next_aff
= 0;
75 static int use_affinity
= 0;
77 pthread_mutex_t affinity_mutex
= PTHREAD_MUTEX_INITIALIZER
;
79 static void set_affinity(void)
81 #ifdef HAVE_SCHED_SETAFFINITY
84 #endif /* HAVE_SCHED_SETAFFINITY */
89 #ifdef HAVE_SCHED_SETAFFINITY
90 ret
= pthread_mutex_lock(&affinity_mutex
);
92 perror("Error in pthread mutex lock");
95 cpu
= cpu_affinities
[next_aff
++];
96 ret
= pthread_mutex_unlock(&affinity_mutex
);
98 perror("Error in pthread mutex unlock");
104 sched_setaffinity(0, sizeof(mask
), &mask
);
105 #endif /* HAVE_SCHED_SETAFFINITY */
109 * returns 0 if test should end.
111 static int test_duration_dequeue(void)
116 static int test_duration_enqueue(void)
121 static DEFINE_URCU_TLS(unsigned long long, nr_dequeues
);
122 static DEFINE_URCU_TLS(unsigned long long, nr_enqueues
);
124 static DEFINE_URCU_TLS(unsigned long long, nr_successful_dequeues
);
125 static DEFINE_URCU_TLS(unsigned long long, nr_successful_enqueues
);
127 static unsigned int nr_enqueuers
;
128 static unsigned int nr_dequeuers
;
131 struct cds_lfq_node_rcu list
;
135 static struct cds_lfq_queue_rcu q
;
138 void *thr_enqueuer(void *_count
)
140 unsigned long long *count
= _count
;
142 printf_verbose("thread_begin %s, tid %lu\n",
143 "enqueuer", urcu_get_thread_id());
147 rcu_register_thread();
155 struct test
*node
= malloc(sizeof(*node
));
158 cds_lfq_node_init_rcu(&node
->list
);
160 cds_lfq_enqueue_rcu(&q
, &node
->list
);
162 URCU_TLS(nr_successful_enqueues
)++;
164 if (caa_unlikely(wdelay
))
167 URCU_TLS(nr_enqueues
)++;
168 if (caa_unlikely(!test_duration_enqueue()))
172 rcu_unregister_thread();
174 count
[0] = URCU_TLS(nr_enqueues
);
175 count
[1] = URCU_TLS(nr_successful_enqueues
);
176 printf_verbose("enqueuer thread_end, tid %lu, "
177 "enqueues %llu successful_enqueues %llu\n",
178 urcu_get_thread_id(),
179 URCU_TLS(nr_enqueues
),
180 URCU_TLS(nr_successful_enqueues
));
186 void free_node_cb(struct rcu_head
*head
)
189 caa_container_of(head
, struct test
, rcu
);
194 void *thr_dequeuer(void *_count
)
196 unsigned long long *count
= _count
;
198 printf_verbose("thread_begin %s, tid %lu\n",
199 "dequeuer", urcu_get_thread_id());
203 rcu_register_thread();
211 struct cds_lfq_node_rcu
*qnode
;
214 qnode
= cds_lfq_dequeue_rcu(&q
);
220 node
= caa_container_of(qnode
, struct test
, list
);
221 call_rcu(&node
->rcu
, free_node_cb
);
222 URCU_TLS(nr_successful_dequeues
)++;
225 URCU_TLS(nr_dequeues
)++;
226 if (caa_unlikely(!test_duration_dequeue()))
228 if (caa_unlikely(rduration
))
229 loop_sleep(rduration
);
232 rcu_unregister_thread();
233 printf_verbose("dequeuer thread_end, tid %lu, "
234 "dequeues %llu, successful_dequeues %llu\n",
235 urcu_get_thread_id(),
236 URCU_TLS(nr_dequeues
),
237 URCU_TLS(nr_successful_dequeues
));
238 count
[0] = URCU_TLS(nr_dequeues
);
239 count
[1] = URCU_TLS(nr_successful_dequeues
);
244 void test_end(unsigned long long *nr_dequeues_l
)
246 struct cds_lfq_node_rcu
*snode
;
249 snode
= cds_lfq_dequeue_rcu(&q
);
253 node
= caa_container_of(snode
, struct test
, list
);
254 free(node
); /* no more concurrent access */
261 void show_usage(char **argv
)
263 printf("Usage : %s nr_dequeuers nr_enqueuers duration (s) <OPTIONS>\n",
265 printf("OPTIONS:\n");
266 printf(" [-d delay] (enqueuer period (in loops))\n");
267 printf(" [-c duration] (dequeuer period (in loops))\n");
268 printf(" [-v] (verbose output)\n");
269 printf(" [-a cpu#] [-a cpu#]... (affinity)\n");
273 int main(int argc
, char **argv
)
276 pthread_t
*tid_enqueuer
, *tid_dequeuer
;
278 unsigned long long *count_enqueuer
, *count_dequeuer
;
279 unsigned long long tot_enqueues
= 0, tot_dequeues
= 0;
280 unsigned long long tot_successful_enqueues
= 0,
281 tot_successful_dequeues
= 0;
282 unsigned long long end_dequeues
= 0;
291 err
= sscanf(argv
[1], "%u", &nr_dequeuers
);
297 err
= sscanf(argv
[2], "%u", &nr_enqueuers
);
303 err
= sscanf(argv
[3], "%lu", &duration
);
309 for (i
= 4; i
< argc
; i
++) {
310 if (argv
[i
][0] != '-')
312 switch (argv
[i
][1]) {
319 cpu_affinities
[next_aff
++] = a
;
321 printf_verbose("Adding CPU %d affinity\n", a
);
328 rduration
= atol(argv
[++i
]);
335 wdelay
= atol(argv
[++i
]);
343 printf_verbose("running test for %lu seconds, %u enqueuers, "
345 duration
, nr_enqueuers
, nr_dequeuers
);
346 printf_verbose("Writer delay : %lu loops.\n", rduration
);
347 printf_verbose("Reader duration : %lu loops.\n", wdelay
);
348 printf_verbose("thread %-6s, tid %lu\n",
349 "main", urcu_get_thread_id());
351 tid_enqueuer
= calloc(nr_enqueuers
, sizeof(*tid_enqueuer
));
352 tid_dequeuer
= calloc(nr_dequeuers
, sizeof(*tid_dequeuer
));
353 count_enqueuer
= calloc(nr_enqueuers
, 2 * sizeof(*count_enqueuer
));
354 count_dequeuer
= calloc(nr_dequeuers
, 2 * sizeof(*count_dequeuer
));
355 cds_lfq_init_rcu(&q
, call_rcu
);
356 err
= create_all_cpu_call_rcu_data(0);
358 printf("Per-CPU call_rcu() worker threads unavailable. Using default global worker thread.\n");
363 for (i_thr
= 0; i_thr
< nr_enqueuers
; i_thr
++) {
364 err
= pthread_create(&tid_enqueuer
[i_thr
], NULL
, thr_enqueuer
,
365 &count_enqueuer
[2 * i_thr
]);
369 for (i_thr
= 0; i_thr
< nr_dequeuers
; i_thr
++) {
370 err
= pthread_create(&tid_dequeuer
[i_thr
], NULL
, thr_dequeuer
,
371 &count_dequeuer
[2 * i_thr
]);
380 for (i_thr
= 0; i_thr
< duration
; i_thr
++) {
383 fwrite(".", sizeof(char), 1, stdout
);
390 for (i_thr
= 0; i_thr
< nr_enqueuers
; i_thr
++) {
391 err
= pthread_join(tid_enqueuer
[i_thr
], &tret
);
394 tot_enqueues
+= count_enqueuer
[2 * i_thr
];
395 tot_successful_enqueues
+= count_enqueuer
[2 * i_thr
+ 1];
397 for (i_thr
= 0; i_thr
< nr_dequeuers
; i_thr
++) {
398 err
= pthread_join(tid_dequeuer
[i_thr
], &tret
);
401 tot_dequeues
+= count_dequeuer
[2 * i_thr
];
402 tot_successful_dequeues
+= count_dequeuer
[2 * i_thr
+ 1];
405 test_end(&end_dequeues
);
406 err
= cds_lfq_destroy_rcu(&q
);
407 urcu_posix_assert(!err
);
409 printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
410 tot_enqueues
, tot_dequeues
);
411 printf_verbose("total number of successful enqueues : %llu, "
412 "successful dequeues %llu\n",
413 tot_successful_enqueues
, tot_successful_dequeues
);
414 printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
416 "rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
417 "successful enqueues %12llu successful dequeues %12llu "
418 "end_dequeues %llu nr_ops %12llu\n",
419 argv
[0], duration
, nr_enqueuers
, wdelay
,
420 nr_dequeuers
, rduration
, tot_enqueues
, tot_dequeues
,
421 tot_successful_enqueues
,
422 tot_successful_dequeues
, end_dequeues
,
423 tot_enqueues
+ tot_dequeues
);
424 if (tot_successful_enqueues
!= tot_successful_dequeues
+ end_dequeues
)
425 printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
426 "succ. dequeues + end dequeues %llu.\n",
427 tot_successful_enqueues
,
428 tot_successful_dequeues
+ end_dequeues
);
430 free_all_cpu_call_rcu_data();
431 free(count_enqueuer
);
432 free(count_dequeuer
);