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>
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 #if HAVE_SCHED_SETAFFINITY
84 #endif /* HAVE_SCHED_SETAFFINITY */
89 #if 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
;
137 void *thr_enqueuer(void *_count
)
139 unsigned long long *count
= _count
;
141 printf_verbose("thread_begin %s, tid %lu\n",
142 "enqueuer", urcu_get_thread_id());
146 rcu_register_thread();
154 struct test
*node
= malloc(sizeof(*node
));
157 cds_lfq_node_init_rcu(&node
->list
);
159 cds_lfq_enqueue_rcu(&q
, &node
->list
);
161 URCU_TLS(nr_successful_enqueues
)++;
163 if (caa_unlikely(wdelay
))
166 URCU_TLS(nr_enqueues
)++;
167 if (caa_unlikely(!test_duration_enqueue()))
171 rcu_unregister_thread();
173 count
[0] = URCU_TLS(nr_enqueues
);
174 count
[1] = URCU_TLS(nr_successful_enqueues
);
175 printf_verbose("enqueuer thread_end, tid %lu, "
176 "enqueues %llu successful_enqueues %llu\n",
177 urcu_get_thread_id(),
178 URCU_TLS(nr_enqueues
),
179 URCU_TLS(nr_successful_enqueues
));
185 void free_node_cb(struct rcu_head
*head
)
188 caa_container_of(head
, struct test
, rcu
);
192 void *thr_dequeuer(void *_count
)
194 unsigned long long *count
= _count
;
196 printf_verbose("thread_begin %s, tid %lu\n",
197 "dequeuer", urcu_get_thread_id());
201 rcu_register_thread();
209 struct cds_lfq_node_rcu
*qnode
;
212 qnode
= cds_lfq_dequeue_rcu(&q
);
218 node
= caa_container_of(qnode
, struct test
, list
);
219 call_rcu(&node
->rcu
, free_node_cb
);
220 URCU_TLS(nr_successful_dequeues
)++;
223 URCU_TLS(nr_dequeues
)++;
224 if (caa_unlikely(!test_duration_dequeue()))
226 if (caa_unlikely(rduration
))
227 loop_sleep(rduration
);
230 rcu_unregister_thread();
231 printf_verbose("dequeuer thread_end, tid %lu, "
232 "dequeues %llu, successful_dequeues %llu\n",
233 urcu_get_thread_id(),
234 URCU_TLS(nr_dequeues
),
235 URCU_TLS(nr_successful_dequeues
));
236 count
[0] = URCU_TLS(nr_dequeues
);
237 count
[1] = URCU_TLS(nr_successful_dequeues
);
241 void test_end(struct cds_lfq_queue_rcu
*q
, unsigned long long *nr_dequeues
)
243 struct cds_lfq_node_rcu
*snode
;
246 snode
= cds_lfq_dequeue_rcu(q
);
250 node
= caa_container_of(snode
, struct test
, list
);
251 free(node
); /* no more concurrent access */
257 void show_usage(int argc
, char **argv
)
259 printf("Usage : %s nr_dequeuers nr_enqueuers duration (s) <OPTIONS>\n",
261 printf("OPTIONS:\n");
262 printf(" [-d delay] (enqueuer period (in loops))\n");
263 printf(" [-c duration] (dequeuer period (in loops))\n");
264 printf(" [-v] (verbose output)\n");
265 printf(" [-a cpu#] [-a cpu#]... (affinity)\n");
269 int main(int argc
, char **argv
)
272 pthread_t
*tid_enqueuer
, *tid_dequeuer
;
274 unsigned long long *count_enqueuer
, *count_dequeuer
;
275 unsigned long long tot_enqueues
= 0, tot_dequeues
= 0;
276 unsigned long long tot_successful_enqueues
= 0,
277 tot_successful_dequeues
= 0;
278 unsigned long long end_dequeues
= 0;
283 show_usage(argc
, argv
);
287 err
= sscanf(argv
[1], "%u", &nr_dequeuers
);
289 show_usage(argc
, argv
);
293 err
= sscanf(argv
[2], "%u", &nr_enqueuers
);
295 show_usage(argc
, argv
);
299 err
= sscanf(argv
[3], "%lu", &duration
);
301 show_usage(argc
, argv
);
305 for (i
= 4; i
< argc
; i
++) {
306 if (argv
[i
][0] != '-')
308 switch (argv
[i
][1]) {
311 show_usage(argc
, argv
);
315 cpu_affinities
[next_aff
++] = a
;
317 printf_verbose("Adding CPU %d affinity\n", a
);
321 show_usage(argc
, argv
);
324 rduration
= atol(argv
[++i
]);
328 show_usage(argc
, argv
);
331 wdelay
= atol(argv
[++i
]);
339 printf_verbose("running test for %lu seconds, %u enqueuers, "
341 duration
, nr_enqueuers
, nr_dequeuers
);
342 printf_verbose("Writer delay : %lu loops.\n", rduration
);
343 printf_verbose("Reader duration : %lu loops.\n", wdelay
);
344 printf_verbose("thread %-6s, tid %lu\n",
345 "main", urcu_get_thread_id());
347 tid_enqueuer
= calloc(nr_enqueuers
, sizeof(*tid_enqueuer
));
348 tid_dequeuer
= calloc(nr_dequeuers
, sizeof(*tid_dequeuer
));
349 count_enqueuer
= calloc(nr_enqueuers
, 2 * sizeof(*count_enqueuer
));
350 count_dequeuer
= calloc(nr_dequeuers
, 2 * sizeof(*count_dequeuer
));
351 cds_lfq_init_rcu(&q
, call_rcu
);
352 err
= create_all_cpu_call_rcu_data(0);
354 printf("Per-CPU call_rcu() worker threads unavailable. Using default global worker thread.\n");
359 for (i_thr
= 0; i_thr
< nr_enqueuers
; i_thr
++) {
360 err
= pthread_create(&tid_enqueuer
[i_thr
], NULL
, thr_enqueuer
,
361 &count_enqueuer
[2 * i_thr
]);
365 for (i_thr
= 0; i_thr
< nr_dequeuers
; i_thr
++) {
366 err
= pthread_create(&tid_dequeuer
[i_thr
], NULL
, thr_dequeuer
,
367 &count_dequeuer
[2 * i_thr
]);
376 for (i_thr
= 0; i_thr
< duration
; i_thr
++) {
379 fwrite(".", sizeof(char), 1, stdout
);
386 for (i_thr
= 0; i_thr
< nr_enqueuers
; i_thr
++) {
387 err
= pthread_join(tid_enqueuer
[i_thr
], &tret
);
390 tot_enqueues
+= count_enqueuer
[2 * i_thr
];
391 tot_successful_enqueues
+= count_enqueuer
[2 * i_thr
+ 1];
393 for (i_thr
= 0; i_thr
< nr_dequeuers
; i_thr
++) {
394 err
= pthread_join(tid_dequeuer
[i_thr
], &tret
);
397 tot_dequeues
+= count_dequeuer
[2 * i_thr
];
398 tot_successful_dequeues
+= count_dequeuer
[2 * i_thr
+ 1];
401 test_end(&q
, &end_dequeues
);
402 err
= cds_lfq_destroy_rcu(&q
);
405 printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
406 tot_enqueues
, tot_dequeues
);
407 printf_verbose("total number of successful enqueues : %llu, "
408 "successful dequeues %llu\n",
409 tot_successful_enqueues
, tot_successful_dequeues
);
410 printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
412 "rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
413 "successful enqueues %12llu successful dequeues %12llu "
414 "end_dequeues %llu nr_ops %12llu\n",
415 argv
[0], duration
, nr_enqueuers
, wdelay
,
416 nr_dequeuers
, rduration
, tot_enqueues
, tot_dequeues
,
417 tot_successful_enqueues
,
418 tot_successful_dequeues
, end_dequeues
,
419 tot_enqueues
+ tot_dequeues
);
420 if (tot_successful_enqueues
!= tot_successful_dequeues
+ end_dequeues
)
421 printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
422 "succ. dequeues + end dequeues %llu.\n",
423 tot_successful_enqueues
,
424 tot_successful_dequeues
+ end_dequeues
);
426 free_all_cpu_call_rcu_data();
427 free(count_enqueuer
);
428 free(count_dequeuer
);