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.
28 #include <sys/types.h>
33 #include <sys/syscall.h>
38 #if defined(_syscall0)
39 _syscall0(pid_t
, gettid
)
40 #elif defined(__NR_gettid)
41 static inline pid_t
gettid(void)
43 return syscall(__NR_gettid
);
46 #warning "use pid as tid"
47 static inline pid_t
gettid(void)
53 #ifndef DYNAMIC_LINK_TEST
56 #define debug_yield_read()
64 static volatile int test_go
, test_stop
;
68 static struct test_array
*test_rcu_pointer
;
70 static unsigned long duration
;
72 /* read-side C.S. duration, in us */
73 static unsigned long rduration
;
76 * returns 0 if test should end.
78 static int test_duration_write(void)
83 static int test_duration_read(void)
88 static unsigned long long __thread nr_writes
;
89 static unsigned long long __thread nr_reads
;
91 static unsigned int nr_readers
;
92 static unsigned int nr_writers
;
94 pthread_mutex_t rcu_copy_mutex
= PTHREAD_MUTEX_INITIALIZER
;
96 void rcu_copy_mutex_lock(void)
99 ret
= pthread_mutex_lock(&rcu_copy_mutex
);
101 perror("Error in pthread mutex lock");
106 void rcu_copy_mutex_unlock(void)
110 ret
= pthread_mutex_unlock(&rcu_copy_mutex
);
112 perror("Error in pthread mutex unlock");
118 * malloc/free are reusing memory areas too quickly, which does not let us
119 * test races appropriately. Use a large circular array for allocations.
120 * ARRAY_SIZE is larger than nr_writers, which insures we never run over our tail.
122 #define ARRAY_SIZE (1048576 * nr_writers)
123 #define ARRAY_POISON 0xDEADBEEF
124 static int array_index
;
125 static struct test_array
*test_array
;
127 static struct test_array
*test_array_alloc(void)
129 struct test_array
*ret
;
132 rcu_copy_mutex_lock();
133 index
= array_index
% ARRAY_SIZE
;
134 assert(test_array
[index
].a
== ARRAY_POISON
||
135 test_array
[index
].a
== 0);
136 ret
= &test_array
[index
];
138 if (array_index
== ARRAY_SIZE
)
140 rcu_copy_mutex_unlock();
144 static void test_array_free(struct test_array
*ptr
)
148 rcu_copy_mutex_lock();
149 ptr
->a
= ARRAY_POISON
;
150 rcu_copy_mutex_unlock();
153 void *thr_reader(void *_count
)
155 unsigned long long *count
= _count
;
156 struct test_array
*local_ptr
;
158 printf("thread_begin %s, thread id : %lx, tid %lu\n",
159 "reader", pthread_self(), (unsigned long)gettid());
161 rcu_register_thread();
170 local_ptr
= rcu_dereference(test_rcu_pointer
);
173 assert(local_ptr
->a
== 8);
174 if (unlikely(rduration
))
178 if (unlikely(!test_duration_read()))
182 rcu_unregister_thread();
185 printf("thread_end %s, thread id : %lx, tid %lu\n",
186 "reader", pthread_self(), (unsigned long)gettid());
191 void *thr_writer(void *_count
)
193 unsigned long long *count
= _count
;
194 struct test_array
*new, *old
;
196 printf("thread_begin %s, thread id : %lx, tid %lu\n",
197 "writer", pthread_self(), (unsigned long)gettid());
205 new = test_array_alloc();
206 rcu_copy_mutex_lock();
207 old
= test_rcu_pointer
;
211 old
= rcu_publish_content(&test_rcu_pointer
, new);
212 rcu_copy_mutex_unlock();
213 /* can be done after unlock */
216 test_array_free(old
);
218 if (unlikely(!test_duration_write()))
220 if (unlikely(wdelay
))
224 printf("thread_end %s, thread id : %lx, tid %lu\n",
225 "writer", pthread_self(), (unsigned long)gettid());
230 void show_usage(int argc
, char **argv
)
232 printf("Usage : %s nr_readers nr_writers duration (s)", argv
[0]);
234 printf(" [-r] [-w] (yield reader and/or writer)");
236 printf(" [-d delay] (writer period (us))");
237 printf(" [-c duration] (reader C.S. duration (us))");
238 printf(" [-a cpu#] [-a cpu#]... (affinity)");
244 int main(int argc
, char **argv
)
247 pthread_t
*tid_reader
, *tid_writer
;
249 unsigned long long *count_reader
, *count_writer
;
250 unsigned long long tot_reads
= 0, tot_writes
= 0;
252 int use_affinity
= 0;
255 show_usage(argc
, argv
);
259 err
= sscanf(argv
[1], "%u", &nr_readers
);
261 show_usage(argc
, argv
);
265 err
= sscanf(argv
[2], "%u", &nr_writers
);
267 show_usage(argc
, argv
);
271 err
= sscanf(argv
[3], "%lu", &duration
);
273 show_usage(argc
, argv
);
279 for (i
= 4; i
< argc
; i
++) {
280 if (argv
[i
][0] != '-')
282 switch (argv
[i
][1]) {
285 yield_active
|= YIELD_READ
;
288 yield_active
|= YIELD_WRITE
;
293 show_usage(argc
, argv
);
297 CPU_SET(a
, &affinity
);
299 printf("Adding CPU %d affinity\n", a
);
303 show_usage(argc
, argv
);
306 rduration
= atoi(argv
[++i
]);
310 show_usage(argc
, argv
);
313 wdelay
= atoi(argv
[++i
]);
318 printf("running test for %lu seconds, %u readers, %u writers.\n",
319 duration
, nr_readers
, nr_writers
);
320 printf("Writer delay : %u us.\n", wdelay
);
321 printf("thread %-6s, thread id : %lx, tid %lu\n",
322 "main", pthread_self(), (unsigned long)gettid());
325 && sched_setaffinity(0, sizeof(affinity
), &affinity
) < 0) {
326 perror("sched_setaffinity");
330 test_array
= malloc(sizeof(*test_array
) * ARRAY_SIZE
);
331 tid_reader
= malloc(sizeof(*tid_reader
) * nr_readers
);
332 tid_writer
= malloc(sizeof(*tid_writer
) * nr_writers
);
333 count_reader
= malloc(sizeof(*count_reader
) * nr_readers
);
334 count_writer
= malloc(sizeof(*count_writer
) * nr_writers
);
336 for (i
= 0; i
< nr_readers
; i
++) {
337 err
= pthread_create(&tid_reader
[i
], NULL
, thr_reader
,
342 for (i
= 0; i
< nr_writers
; i
++) {
343 err
= pthread_create(&tid_writer
[i
], NULL
, thr_writer
,
357 for (i
= 0; i
< nr_readers
; i
++) {
358 err
= pthread_join(tid_reader
[i
], &tret
);
361 tot_reads
+= count_reader
[i
];
363 for (i
= 0; i
< nr_writers
; i
++) {
364 err
= pthread_join(tid_writer
[i
], &tret
);
367 tot_writes
+= count_writer
[i
];
370 printf("total number of reads : %llu, writes %llu\n", tot_reads
,
372 test_array_free(test_rcu_pointer
);