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)
52 #include "urcu-qsbr.h"
58 static volatile int test_go
, test_stop
;
62 static struct test_array
*test_rcu_pointer
;
64 static unsigned long duration
;
67 * returns 0 if test should end.
69 static int test_duration_write(void)
74 static int test_duration_read(void)
79 static unsigned long long __thread nr_writes
;
80 static unsigned long long __thread nr_reads
;
82 static unsigned int nr_readers
;
83 static unsigned int nr_writers
;
85 pthread_mutex_t rcu_copy_mutex
= PTHREAD_MUTEX_INITIALIZER
;
87 void rcu_copy_mutex_lock(void)
90 ret
= pthread_mutex_lock(&rcu_copy_mutex
);
92 perror("Error in pthread mutex lock");
97 void rcu_copy_mutex_unlock(void)
101 ret
= pthread_mutex_unlock(&rcu_copy_mutex
);
103 perror("Error in pthread mutex unlock");
109 * malloc/free are reusing memory areas too quickly, which does not let us
110 * test races appropriately. Use a large circular array for allocations.
111 * ARRAY_SIZE is larger than nr_writers, which insures we never run over our tail.
113 #define ARRAY_SIZE (1048576 * nr_writers)
114 #define ARRAY_POISON 0xDEADBEEF
115 static int array_index
;
116 static struct test_array
*test_array
;
118 static struct test_array
*test_array_alloc(void)
120 struct test_array
*ret
;
123 rcu_copy_mutex_lock();
124 index
= array_index
% ARRAY_SIZE
;
125 assert(test_array
[index
].a
== ARRAY_POISON
||
126 test_array
[index
].a
== 0);
127 ret
= &test_array
[index
];
129 if (array_index
== ARRAY_SIZE
)
131 rcu_copy_mutex_unlock();
135 static void test_array_free(struct test_array
*ptr
)
139 rcu_copy_mutex_lock();
140 ptr
->a
= ARRAY_POISON
;
141 rcu_copy_mutex_unlock();
144 void *thr_reader(void *_count
)
146 unsigned long long *count
= _count
;
147 struct test_array
*local_ptr
;
149 printf("thread_begin %s, thread id : %lx, tid %lu\n",
150 "reader", pthread_self(), (unsigned long)gettid());
152 rcu_register_thread();
161 local_ptr
= _rcu_dereference(test_rcu_pointer
);
164 assert(local_ptr
->a
== 8);
167 /* QS each 1024 reads */
168 if ((nr_reads
& ((1 << 10) - 1)) == 0)
169 _rcu_quiescent_state();
170 if (!test_duration_read())
174 rcu_unregister_thread();
177 printf("thread_end %s, thread id : %lx, tid %lu\n",
178 "reader", pthread_self(), (unsigned long)gettid());
183 void *thr_writer(void *_count
)
185 unsigned long long *count
= _count
;
186 struct test_array
*new, *old
;
188 printf("thread_begin %s, thread id : %lx, tid %lu\n",
189 "writer", pthread_self(), (unsigned long)gettid());
197 new = test_array_alloc();
198 rcu_copy_mutex_lock();
199 old
= test_rcu_pointer
;
203 old
= _rcu_publish_content(&test_rcu_pointer
, new);
204 rcu_copy_mutex_unlock();
205 /* can be done after unlock */
208 test_array_free(old
);
210 if (!test_duration_write())
216 printf("thread_end %s, thread id : %lx, tid %lu\n",
217 "writer", pthread_self(), (unsigned long)gettid());
222 void show_usage(int argc
, char **argv
)
224 printf("Usage : %s nr_readers nr_writers duration (s)", argv
[0]);
226 printf(" [-r] [-w] (yield reader and/or writer)");
228 printf(" [-d delay] (writer period (us))");
232 int main(int argc
, char **argv
)
235 pthread_t
*tid_reader
, *tid_writer
;
237 unsigned long long *count_reader
, *count_writer
;
238 unsigned long long tot_reads
= 0, tot_writes
= 0;
242 show_usage(argc
, argv
);
246 err
= sscanf(argv
[1], "%u", &nr_readers
);
248 show_usage(argc
, argv
);
252 err
= sscanf(argv
[2], "%u", &nr_writers
);
254 show_usage(argc
, argv
);
258 err
= sscanf(argv
[3], "%lu", &duration
);
260 show_usage(argc
, argv
);
264 for (i
= 4; i
< argc
; i
++) {
265 if (argv
[i
][0] != '-')
267 switch (argv
[i
][1]) {
270 yield_active
|= YIELD_READ
;
273 yield_active
|= YIELD_WRITE
;
278 show_usage(argc
, argv
);
281 wdelay
= atoi(argv
[++i
]);
286 printf("running test for %lu seconds, %u readers, %u writers.\n",
287 duration
, nr_readers
, nr_writers
);
288 printf("Writer delay : %u us.\n", wdelay
);
289 printf("thread %-6s, thread id : %lx, tid %lu\n",
290 "main", pthread_self(), (unsigned long)gettid());
292 test_array
= malloc(sizeof(*test_array
) * ARRAY_SIZE
);
293 tid_reader
= malloc(sizeof(*tid_reader
) * nr_readers
);
294 tid_writer
= malloc(sizeof(*tid_writer
) * nr_writers
);
295 count_reader
= malloc(sizeof(*count_reader
) * nr_readers
);
296 count_writer
= malloc(sizeof(*count_writer
) * nr_writers
);
298 for (i
= 0; i
< nr_readers
; i
++) {
299 err
= pthread_create(&tid_reader
[i
], NULL
, thr_reader
,
304 for (i
= 0; i
< nr_writers
; i
++) {
305 err
= pthread_create(&tid_writer
[i
], NULL
, thr_writer
,
319 for (i
= 0; i
< nr_readers
; i
++) {
320 err
= pthread_join(tid_reader
[i
], &tret
);
323 tot_reads
+= count_reader
[i
];
325 for (i
= 0; i
< nr_writers
; i
++) {
326 err
= pthread_join(tid_writer
[i
], &tret
);
329 tot_writes
+= count_writer
[i
];
332 printf("total number of reads : %llu, writes %llu\n", tot_reads
,
334 test_array_free(test_rcu_pointer
);