#define INNER_READ_LOOP 100000U
#define READ_LOOP ((unsigned long long)OUTER_READ_LOOP * INNER_READ_LOOP)
-#define WRITE_LOOP 2000U
+#define OUTER_WRITE_LOOP 10U
+#define INNER_WRITE_LOOP 200U
+#define WRITE_LOOP ((unsigned long long)OUTER_WRITE_LOOP * INNER_WRITE_LOOP)
-#define NR_READ 10
-#define NR_WRITE 9
+static int num_read;
+static int num_write;
-static cycles_t reader_time[NR_READ] __attribute__((aligned(128)));
+#define NR_READ num_read
+#define NR_WRITE num_write
+
+static cycles_t __attribute__((aligned(128))) *reader_time;
+static cycles_t __attribute__((aligned(128))) *writer_time;
void *thr_reader(void *arg)
{
void *thr_writer(void *arg)
{
- int i;
+ int i, j;
+ cycles_t time1, time2;
printf("thread_begin %s, thread id : %lx, tid %lu\n",
"writer", pthread_self(), (unsigned long)gettid());
sleep(2);
- for (i = 0; i < WRITE_LOOP; i++) {
- pthread_rwlock_wrlock(&lock);
- test_array.a = 8;
- pthread_rwlock_unlock(&lock);
- usleep(1);
+ for (i = 0; i < OUTER_WRITE_LOOP; i++) {
+ for (j = 0; j < INNER_WRITE_LOOP; j++) {
+ time1 = get_cycles();
+ pthread_rwlock_wrlock(&lock);
+ test_array.a = 8;
+ pthread_rwlock_unlock(&lock);
+ time2 = get_cycles();
+ writer_time[(unsigned long)arg] += time2 - time1;
+ usleep(1);
+ }
}
printf("thread_end %s, thread id : %lx, tid %lu\n",
return ((void*)2);
}
-int main()
+int main(int argc, char **argv)
{
int err;
- pthread_t tid_reader[NR_READ], tid_writer[NR_WRITE];
+ pthread_t *tid_reader, *tid_writer;
void *tret;
int i;
- cycles_t tot_time = 0;
+ cycles_t tot_rtime = 0;
+ cycles_t tot_wtime = 0;
+
+ if (argc < 2) {
+ printf("Usage : %s nr_readers nr_writers\n", argv[0]);
+ exit(-1);
+ }
+ num_read = atoi(argv[1]);
+ num_write = atoi(argv[2]);
+
+ reader_time = malloc(sizeof(*reader_time) * num_read);
+ writer_time = malloc(sizeof(*writer_time) * num_write);
+ tid_reader = malloc(sizeof(*tid_reader) * num_read);
+ tid_writer = malloc(sizeof(*tid_writer) * num_write);
printf("thread %-6s, thread id : %lx, tid %lu\n",
"main", pthread_self(), (unsigned long)gettid());
exit(1);
}
for (i = 0; i < NR_WRITE; i++) {
- err = pthread_create(&tid_writer[i], NULL, thr_writer, NULL);
+ err = pthread_create(&tid_writer[i], NULL, thr_writer,
+ (void *)(long)i);
if (err != 0)
exit(1);
}
err = pthread_join(tid_reader[i], &tret);
if (err != 0)
exit(1);
- tot_time += reader_time[i];
+ tot_rtime += reader_time[i];
}
for (i = 0; i < NR_WRITE; i++) {
err = pthread_join(tid_writer[i], &tret);
if (err != 0)
exit(1);
+ tot_wtime += writer_time[i];
}
printf("Time per read : %g cycles\n",
- (double)tot_time / ((double)NR_READ * (double)READ_LOOP));
+ (double)tot_rtime / ((double)NR_READ * (double)READ_LOOP));
+ printf("Time per write : %g cycles\n",
+ (double)tot_wtime / ((double)NR_WRITE * (double)WRITE_LOOP));
+
+ free(reader_time);
+ free(writer_time);
+ free(tid_reader);
+ free(tid_writer);
return 0;
}