4 * Userspace RCU library - test program
6 * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
27 #include <sys/types.h>
32 #include <sys/syscall.h>
36 #if defined(_syscall0)
37 _syscall0(pid_t
, gettid
)
38 #elif defined(__NR_gettid)
39 static inline pid_t
gettid(void)
41 return syscall(__NR_gettid
);
44 #warning "use pid as tid"
45 static inline pid_t
gettid(void)
51 #ifndef DYNAMIC_LINK_TEST
54 #define debug_yield_read()
62 static volatile int test_go
, test_stop
;
66 static struct test_array
*test_rcu_pointer
;
68 static unsigned long duration
;
71 * returns 0 if test should end.
73 static int test_duration_write(void)
78 static int test_duration_read(void)
83 static unsigned long long __thread nr_writes
;
84 static unsigned long long __thread nr_reads
;
86 static unsigned int nr_readers
;
87 static unsigned int nr_writers
;
89 pthread_mutex_t rcu_copy_mutex
= PTHREAD_MUTEX_INITIALIZER
;
91 void rcu_copy_mutex_lock(void)
94 ret
= pthread_mutex_lock(&rcu_copy_mutex
);
96 perror("Error in pthread mutex lock");
101 void rcu_copy_mutex_unlock(void)
105 ret
= pthread_mutex_unlock(&rcu_copy_mutex
);
107 perror("Error in pthread mutex unlock");
113 * malloc/free are reusing memory areas too quickly, which does not let us
114 * test races appropriately. Use a large circular array for allocations.
115 * ARRAY_SIZE is larger than nr_writers, which insures we never run over our tail.
117 #define ARRAY_SIZE (1048576 * nr_writers)
118 #define ARRAY_POISON 0xDEADBEEF
119 static int array_index
;
120 static struct test_array
*test_array
;
122 static struct test_array
*test_array_alloc(void)
124 struct test_array
*ret
;
127 rcu_copy_mutex_lock();
128 index
= array_index
% ARRAY_SIZE
;
129 assert(test_array
[index
].a
== ARRAY_POISON
||
130 test_array
[index
].a
== 0);
131 ret
= &test_array
[index
];
133 if (array_index
== ARRAY_SIZE
)
135 rcu_copy_mutex_unlock();
139 static void test_array_free(struct test_array
*ptr
)
143 rcu_copy_mutex_lock();
144 ptr
->a
= ARRAY_POISON
;
145 rcu_copy_mutex_unlock();
148 void *thr_reader(void *_count
)
150 unsigned long long *count
= _count
;
151 struct test_array
*local_ptr
;
153 printf("thread_begin %s, thread id : %lx, tid %lu\n",
154 "reader", pthread_self(), (unsigned long)gettid());
156 rcu_register_thread();
165 local_ptr
= rcu_dereference(test_rcu_pointer
);
168 assert(local_ptr
->a
== 8);
171 if (!test_duration_read())
175 rcu_unregister_thread();
178 printf("thread_end %s, thread id : %lx, tid %lu\n",
179 "reader", pthread_self(), (unsigned long)gettid());
184 void *thr_writer(void *_count
)
186 unsigned long long *count
= _count
;
187 struct test_array
*new, *old
;
189 printf("thread_begin %s, thread id : %lx, tid %lu\n",
190 "writer", pthread_self(), (unsigned long)gettid());
198 new = test_array_alloc();
199 rcu_copy_mutex_lock();
200 old
= test_rcu_pointer
;
204 old
= rcu_publish_content(&test_rcu_pointer
, new);
205 rcu_copy_mutex_unlock();
206 /* can be done after unlock */
209 test_array_free(old
);
211 if (!test_duration_write())
217 printf("thread_end %s, thread id : %lx, tid %lu\n",
218 "writer", pthread_self(), (unsigned long)gettid());
223 void show_usage(int argc
, char **argv
)
225 printf("Usage : %s nr_readers nr_writers duration (s)", argv
[0]);
227 printf(" [-r] [-w] (yield reader and/or writer)");
229 printf(" [-d delay] (writer period (us))");
233 int main(int argc
, char **argv
)
236 pthread_t
*tid_reader
, *tid_writer
;
238 unsigned long long *count_reader
, *count_writer
;
239 unsigned long long tot_reads
= 0, tot_writes
= 0;
243 show_usage(argc
, argv
);
247 err
= sscanf(argv
[1], "%u", &nr_readers
);
249 show_usage(argc
, argv
);
253 err
= sscanf(argv
[2], "%u", &nr_writers
);
255 show_usage(argc
, argv
);
259 err
= sscanf(argv
[3], "%lu", &duration
);
261 show_usage(argc
, argv
);
265 for (i
= 4; i
< argc
; i
++) {
266 if (argv
[i
][0] != '-')
268 switch (argv
[i
][1]) {
271 yield_active
|= YIELD_READ
;
274 yield_active
|= YIELD_WRITE
;
279 show_usage(argc
, argv
);
282 wdelay
= atoi(argv
[++i
]);
287 printf("running test for %lu seconds, %u readers, %u writers.\n",
288 duration
, nr_readers
, nr_writers
);
289 printf("Writer delay : %u us.\n", wdelay
);
290 printf("thread %-6s, thread id : %lx, tid %lu\n",
291 "main", pthread_self(), (unsigned long)gettid());
293 test_array
= malloc(sizeof(*test_array
) * ARRAY_SIZE
);
294 tid_reader
= malloc(sizeof(*tid_reader
) * nr_readers
);
295 tid_writer
= malloc(sizeof(*tid_writer
) * nr_writers
);
296 count_reader
= malloc(sizeof(*count_reader
) * nr_readers
);
297 count_writer
= malloc(sizeof(*count_writer
) * nr_writers
);
299 for (i
= 0; i
< nr_readers
; i
++) {
300 err
= pthread_create(&tid_reader
[i
], NULL
, thr_reader
,
305 for (i
= 0; i
< nr_writers
; i
++) {
306 err
= pthread_create(&tid_writer
[i
], NULL
, thr_writer
,
320 for (i
= 0; i
< nr_readers
; i
++) {
321 err
= pthread_join(tid_reader
[i
], &tret
);
324 tot_reads
+= count_reader
[i
];
326 for (i
= 0; i
< nr_writers
; i
++) {
327 err
= pthread_join(tid_writer
[i
], &tret
);
330 tot_writes
+= count_writer
[i
];
333 printf("total number of reads : %llu, writes %llu\n", tot_reads
,
335 test_array_free(test_rcu_pointer
);