4 * Userspace RCU library - example RCU-based lock-free stack
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.
25 #include "../config.h"
32 #include <sys/types.h>
37 #include <sys/syscall.h>
41 #include <urcu/arch.h>
43 /* hardcoded number of CPUs */
46 #if defined(_syscall0)
47 _syscall0(pid_t
, gettid
)
48 #elif defined(__NR_gettid)
49 static inline pid_t
gettid(void)
51 return syscall(__NR_gettid
);
54 #warning "use pid as tid"
55 static inline pid_t
gettid(void)
61 #ifndef DYNAMIC_LINK_TEST
65 #include <urcu/rcuwfstack.h>
66 #include <urcu-defer.h>
68 static volatile int test_go
, test_stop
;
70 static unsigned long rduration
;
72 static unsigned long duration
;
74 /* read-side C.S. duration, in loops */
75 static unsigned long wdelay
;
77 static inline void loop_sleep(unsigned long l
)
83 static int verbose_mode
;
85 #define printf_verbose(fmt, args...) \
91 static unsigned int cpu_affinities
[NR_CPUS
];
92 static unsigned int next_aff
= 0;
93 static int use_affinity
= 0;
95 pthread_mutex_t affinity_mutex
= PTHREAD_MUTEX_INITIALIZER
;
97 #ifndef HAVE_CPU_SET_T
98 typedef unsigned long cpu_set_t
;
99 # define CPU_ZERO(cpuset) do { *(cpuset) = 0; } while(0)
100 # define CPU_SET(cpu, cpuset) do { *(cpuset) |= (1UL << (cpu)); } while(0)
103 static void set_affinity(void)
112 #if HAVE_SCHED_SETAFFINITY
113 ret
= pthread_mutex_lock(&affinity_mutex
);
115 perror("Error in pthread mutex lock");
118 cpu
= cpu_affinities
[next_aff
++];
119 ret
= pthread_mutex_unlock(&affinity_mutex
);
121 perror("Error in pthread mutex unlock");
127 #if SCHED_SETAFFINITY_ARGS == 2
128 sched_setaffinity(0, &mask
);
130 sched_setaffinity(0, sizeof(mask
), &mask
);
132 #endif /* HAVE_SCHED_SETAFFINITY */
136 * returns 0 if test should end.
138 static int test_duration_dequeue(void)
143 static int test_duration_enqueue(void)
148 static unsigned long long __thread nr_dequeues
;
149 static unsigned long long __thread nr_enqueues
;
151 static unsigned long long __thread nr_successful_dequeues
;
152 static unsigned long long __thread nr_successful_enqueues
;
154 static unsigned int nr_enqueuers
;
155 static unsigned int nr_dequeuers
;
157 static struct rcu_wfs_stack s
;
159 void *thr_enqueuer(void *_count
)
161 unsigned long long *count
= _count
;
163 printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
164 "enqueuer", pthread_self(), (unsigned long)gettid());
168 rcu_register_thread();
176 struct rcu_wfs_node
*node
= malloc(sizeof(*node
));
179 rcu_wfs_node_init(node
);
180 rcu_wfs_push(&s
, node
);
181 nr_successful_enqueues
++;
183 if (unlikely(wdelay
))
187 if (unlikely(!test_duration_enqueue()))
191 rcu_unregister_thread();
193 count
[0] = nr_enqueues
;
194 count
[1] = nr_successful_enqueues
;
195 printf_verbose("enqueuer thread_end, thread id : %lx, tid %lu, "
196 "enqueues %llu successful_enqueues %llu\n",
197 pthread_self(), (unsigned long)gettid(), nr_enqueues
,
198 nr_successful_enqueues
);
203 void *thr_dequeuer(void *_count
)
205 unsigned long long *count
= _count
;
207 printf_verbose("thread_begin %s, thread id : %lx, tid %lu\n",
208 "dequeuer", pthread_self(), (unsigned long)gettid());
212 rcu_defer_register_thread();
213 rcu_register_thread();
221 struct rcu_wfs_node
*node
= rcu_wfs_pop(&s
);
224 defer_rcu(free
, node
);
225 nr_successful_dequeues
++;
229 if (unlikely(!test_duration_dequeue()))
231 if (unlikely(rduration
))
232 loop_sleep(rduration
);
235 rcu_unregister_thread();
236 rcu_defer_unregister_thread();
238 printf_verbose("dequeuer thread_end, thread id : %lx, tid %lu, "
239 "dequeues %llu, successful_dequeues %llu\n",
240 pthread_self(), (unsigned long)gettid(), nr_dequeues
,
241 nr_successful_dequeues
);
242 count
[0] = nr_dequeues
;
243 count
[1] = nr_successful_dequeues
;
247 void test_end(struct rcu_wfs_stack
*s
, unsigned long long *nr_dequeues
)
249 struct rcu_wfs_node
*node
;
252 node
= rcu_wfs_pop(s
);
260 void show_usage(int argc
, char **argv
)
262 printf("Usage : %s nr_dequeuers nr_enqueuers duration (s)", argv
[0]);
263 printf(" [-d delay] (enqueuer period (in loops))");
264 printf(" [-c duration] (dequeuer period (in loops))");
265 printf(" [-v] (verbose output)");
266 printf(" [-a cpu#] [-a cpu#]... (affinity)");
270 int main(int argc
, char **argv
)
273 pthread_t
*tid_enqueuer
, *tid_dequeuer
;
275 unsigned long long *count_enqueuer
, *count_dequeuer
;
276 unsigned long long tot_enqueues
= 0, tot_dequeues
= 0;
277 unsigned long long tot_successful_enqueues
= 0,
278 tot_successful_dequeues
= 0;
279 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, thread id : %lx, tid %lu\n",
345 "main", pthread_self(), (unsigned long)gettid());
347 tid_enqueuer
= malloc(sizeof(*tid_enqueuer
) * nr_enqueuers
);
348 tid_dequeuer
= malloc(sizeof(*tid_dequeuer
) * nr_dequeuers
);
349 count_enqueuer
= malloc(2 * sizeof(*count_enqueuer
) * nr_enqueuers
);
350 count_dequeuer
= malloc(2 * sizeof(*count_dequeuer
) * nr_dequeuers
);
355 for (i
= 0; i
< nr_enqueuers
; i
++) {
356 err
= pthread_create(&tid_enqueuer
[i
], NULL
, thr_enqueuer
,
357 &count_enqueuer
[2 * i
]);
361 for (i
= 0; i
< nr_dequeuers
; i
++) {
362 err
= pthread_create(&tid_dequeuer
[i
], NULL
, thr_dequeuer
,
363 &count_dequeuer
[2 * i
]);
372 for (i
= 0; i
< duration
; i
++) {
380 for (i
= 0; i
< nr_enqueuers
; i
++) {
381 err
= pthread_join(tid_enqueuer
[i
], &tret
);
384 tot_enqueues
+= count_enqueuer
[2 * i
];
385 tot_successful_enqueues
+= count_enqueuer
[2 * i
+ 1];
387 for (i
= 0; i
< nr_dequeuers
; i
++) {
388 err
= pthread_join(tid_dequeuer
[i
], &tret
);
391 tot_dequeues
+= count_dequeuer
[2 * i
];
392 tot_successful_dequeues
+= count_dequeuer
[2 * i
+ 1];
395 test_end(&s
, &end_dequeues
);
397 printf_verbose("total number of enqueues : %llu, dequeues %llu\n",
398 tot_enqueues
, tot_dequeues
);
399 printf_verbose("total number of successful enqueues : %llu, "
400 "successful dequeues %llu\n",
401 tot_successful_enqueues
, tot_successful_dequeues
);
402 printf("SUMMARY %-25s testdur %4lu nr_enqueuers %3u wdelay %6lu "
404 "rdur %6lu nr_enqueues %12llu nr_dequeues %12llu "
405 "successful enqueues %12llu successful dequeues %12llu "
406 "end_dequeues %llu nr_ops %12llu\n",
407 argv
[0], duration
, nr_enqueuers
, wdelay
,
408 nr_dequeuers
, rduration
, tot_enqueues
, tot_dequeues
,
409 tot_successful_enqueues
,
410 tot_successful_dequeues
, end_dequeues
,
411 tot_enqueues
+ tot_dequeues
);
412 if (tot_successful_enqueues
!= tot_successful_dequeues
+ end_dequeues
)
413 printf("WARNING! Discrepancy between nr succ. enqueues %llu vs "
414 "succ. dequeues + end dequeues %llu.\n",
415 tot_successful_enqueues
,
416 tot_successful_dequeues
+ end_dequeues
);
418 free(count_enqueuer
);
419 free(count_dequeuer
);