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>
37 #include <urcu/arch.h>
38 #include <urcu/tls-compat.h>
40 #include "thread-id.h"
42 /* hardcoded number of CPUs */
45 #ifndef DYNAMIC_LINK_TEST
51 static volatile int test_go
, test_stop
;
53 static unsigned long rduration
;
55 static unsigned long duration
;
57 /* read-side C.S. duration, in loops */
58 static unsigned long wdelay
;
60 static inline void loop_sleep(unsigned long loops
)
66 static int verbose_mode
;
68 #define printf_verbose(fmt, args...) \
74 static unsigned int cpu_affinities
[NR_CPUS
];
75 static unsigned int next_aff
= 0;
76 static int use_affinity
= 0;
78 pthread_mutex_t affinity_mutex
= PTHREAD_MUTEX_INITIALIZER
;
80 static void set_affinity(void)
82 #if HAVE_SCHED_SETAFFINITY
85 #endif /* HAVE_SCHED_SETAFFINITY */
90 #if HAVE_SCHED_SETAFFINITY
91 ret
= pthread_mutex_lock(&affinity_mutex
);
93 perror("Error in pthread mutex lock");
96 cpu
= cpu_affinities
[next_aff
++];
97 ret
= pthread_mutex_unlock(&affinity_mutex
);
99 perror("Error in pthread mutex unlock");
105 #if SCHED_SETAFFINITY_ARGS == 2
106 sched_setaffinity(0, &mask
);
108 sched_setaffinity(0, sizeof(mask
), &mask
);
110 #endif /* HAVE_SCHED_SETAFFINITY */
114 * returns 0 if test should end.
116 static int test_duration_dequeue(void)
121 static int test_duration_enqueue(void)
126 static DEFINE_URCU_TLS(unsigned long long, nr_dequeues
);
127 static DEFINE_URCU_TLS(unsigned long long, nr_enqueues
);
129 static DEFINE_URCU_TLS(unsigned long long, nr_successful_dequeues
);
130 static DEFINE_URCU_TLS(unsigned long long, nr_successful_enqueues
);
132 static unsigned int nr_enqueuers
;
133 static unsigned int nr_dequeuers
;
136 struct cds_lfq_node_rcu list
;
140 static struct cds_lfq_queue_rcu q
;
142 void *thr_enqueuer(void *_count
)
144 unsigned long long *count
= _count
;
146 printf_verbose("thread_begin %s, tid %lu\n",
147 "enqueuer", urcu_get_thread_id());
151 rcu_register_thread();
159 struct test
*node
= malloc(sizeof(*node
));
162 cds_lfq_node_init_rcu(&node
->list
);
164 cds_lfq_enqueue_rcu(&q
, &node
->list
);
166 URCU_TLS(nr_successful_enqueues
)++;
168 if (caa_unlikely(wdelay
))
171 URCU_TLS(nr_enqueues
)++;
172 if (caa_unlikely(!test_duration_enqueue()))
176 rcu_unregister_thread();
178 count
[0] = URCU_TLS(nr_enqueues
);
179 count
[1] = URCU_TLS(nr_successful_enqueues
);
180 printf_verbose("enqueuer thread_end, tid %lu, "
181 "enqueues %llu successful_enqueues %llu\n",
182 urcu_get_thread_id(),
183 URCU_TLS(nr_enqueues
),
184 URCU_TLS(nr_successful_enqueues
));
190 void free_node_cb(struct rcu_head
*head
)
193 caa_container_of(head
, struct test
, rcu
);
197 void *thr_dequeuer(void *_count
)
199 unsigned long long *count
= _count
;
201 printf_verbose("thread_begin %s, tid %lu\n",
202 "dequeuer", urcu_get_thread_id());
206 rcu_register_thread();
214 struct cds_lfq_node_rcu
*qnode
;
217 qnode
= cds_lfq_dequeue_rcu(&q
);
223 node
= caa_container_of(qnode
, struct test
, list
);
224 call_rcu(&node
->rcu
, free_node_cb
);
225 URCU_TLS(nr_successful_dequeues
)++;
228 URCU_TLS(nr_dequeues
)++;
229 if (caa_unlikely(!test_duration_dequeue()))
231 if (caa_unlikely(rduration
))
232 loop_sleep(rduration
);
235 rcu_unregister_thread();
236 printf_verbose("dequeuer thread_end, tid %lu, "
237 "dequeues %llu, successful_dequeues %llu\n",
238 urcu_get_thread_id(),
239 URCU_TLS(nr_dequeues
),
240 URCU_TLS(nr_successful_dequeues
));
241 count
[0] = URCU_TLS(nr_dequeues
);
242 count
[1] = URCU_TLS(nr_successful_dequeues
);
246 void test_end(struct cds_lfq_queue_rcu
*q
, unsigned long long *nr_dequeues
)
248 struct cds_lfq_node_rcu
*snode
;
251 snode
= cds_lfq_dequeue_rcu(q
);
255 node
= caa_container_of(snode
, struct test
, list
);
256 free(node
); /* no more concurrent access */
262 void show_usage(int argc
, char **argv
)
264 printf("Usage : %s nr_dequeuers nr_enqueuers duration (s) <OPTIONS>\n",
266 printf("OPTIONS:\n");
267 printf(" [-d delay] (enqueuer period (in loops))\n");
268 printf(" [-c duration] (dequeuer period (in loops))\n");
269 printf(" [-v] (verbose output)\n");
270 printf(" [-a cpu#] [-a cpu#]... (affinity)\n");
274 int main(int argc
, char **argv
)
277 pthread_t
*tid_enqueuer
, *tid_dequeuer
;
279 unsigned long long *count_enqueuer
, *count_dequeuer
;
280 unsigned long long tot_enqueues
= 0, tot_dequeues
= 0;
281 unsigned long long tot_successful_enqueues
= 0,
282 tot_successful_dequeues
= 0;
283 unsigned long long end_dequeues
= 0;
287 show_usage(argc
, argv
);
291 err
= sscanf(argv
[1], "%u", &nr_dequeuers
);
293 show_usage(argc
, argv
);
297 err
= sscanf(argv
[2], "%u", &nr_enqueuers
);
299 show_usage(argc
, argv
);
303 err
= sscanf(argv
[3], "%lu", &duration
);
305 show_usage(argc
, argv
);
309 for (i
= 4; i
< argc
; i
++) {
310 if (argv
[i
][0] != '-')
312 switch (argv
[i
][1]) {
315 show_usage(argc
, argv
);
319 cpu_affinities
[next_aff
++] = a
;
321 printf_verbose("Adding CPU %d affinity\n", a
);
325 show_usage(argc
, argv
);
328 rduration
= atol(argv
[++i
]);
332 show_usage(argc
, argv
);
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
= 0; i
< nr_enqueuers
; i
++) {
364 err
= pthread_create(&tid_enqueuer
[i
], NULL
, thr_enqueuer
,
365 &count_enqueuer
[2 * i
]);
369 for (i
= 0; i
< nr_dequeuers
; i
++) {
370 err
= pthread_create(&tid_dequeuer
[i
], NULL
, thr_dequeuer
,
371 &count_dequeuer
[2 * i
]);
380 for (i
= 0; i
< duration
; i
++) {
383 fwrite(".", sizeof(char), 1, stdout
);
390 for (i
= 0; i
< nr_enqueuers
; i
++) {
391 err
= pthread_join(tid_enqueuer
[i
], &tret
);
394 tot_enqueues
+= count_enqueuer
[2 * i
];
395 tot_successful_enqueues
+= count_enqueuer
[2 * i
+ 1];
397 for (i
= 0; i
< nr_dequeuers
; i
++) {
398 err
= pthread_join(tid_dequeuer
[i
], &tret
);
401 tot_dequeues
+= count_dequeuer
[2 * i
];
402 tot_successful_dequeues
+= count_dequeuer
[2 * i
+ 1];
405 test_end(&q
, &end_dequeues
);
406 err
= cds_lfq_destroy_rcu(&q
);
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
);