tests/benchmark/test_rwlock_timing.c

   1 /*
   2  * test_urcu.c
   3  *
   4  * Userspace RCU library - test program
   5  *
   6  * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   7  *
   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.
  12  *
  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.
  17  *
  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.
  21  */
  22
  23 #include <stdio.h>
  24 #include <pthread.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <sys/types.h>
  28 #include <sys/wait.h>
  29 #include <unistd.h>
  30 #include <stdio.h>
  31 #include <assert.h>
  32 #include <pthread.h>
  33 #include <errno.h>
  34
  35 #include <urcu/arch.h>
  36
  37 #include "thread-id.h"
  38
  39 #include <urcu.h>
  40
  41 struct test_array {
  42         int a;
  43 };
  44
  45 pthread_rwlock_t lock = PTHREAD_RWLOCK_INITIALIZER;
  46
  47 static struct test_array test_array = { 8 };
  48
  49 #define OUTER_READ_LOOP 200U
  50 #define INNER_READ_LOOP 100000U
  51 #define READ_LOOP ((unsigned long long)OUTER_READ_LOOP * INNER_READ_LOOP)
  52
  53 #define OUTER_WRITE_LOOP 10U
  54 #define INNER_WRITE_LOOP 200U
  55 #define WRITE_LOOP ((unsigned long long)OUTER_WRITE_LOOP * INNER_WRITE_LOOP)
  56
  57 static int num_read;
  58 static int num_write;
  59
  60 #define NR_READ num_read
  61 #define NR_WRITE num_write
  62
  63 static caa_cycles_t __attribute__((aligned(CAA_CACHE_LINE_SIZE))) *reader_time;
  64 static caa_cycles_t __attribute__((aligned(CAA_CACHE_LINE_SIZE))) *writer_time;
  65
  66 void *thr_reader(void *arg)
  67 {
  68         int i, j;
  69         caa_cycles_t time1, time2;
  70
  71         printf("thread_begin %s, tid %lu\n",
  72                 "reader", urcu_get_thread_id());
  73         sleep(2);
  74
  75         time1 = caa_get_cycles();
  76         for (i = 0; i < OUTER_READ_LOOP; i++) {
  77                 for (j = 0; j < INNER_READ_LOOP; j++) {
  78                         pthread_rwlock_rdlock(&lock);
  79                         assert(test_array.a == 8);
  80                         pthread_rwlock_unlock(&lock);
  81                 }
  82         }
  83         time2 = caa_get_cycles();
  84
  85         reader_time[(unsigned long)arg] = time2 - time1;
  86
  87         sleep(2);
  88         printf("thread_end %s, tid %lu\n",
  89                 "reader", urcu_get_thread_id());
  90         return ((void*)1);
  91
  92 }
  93
  94 void *thr_writer(void *arg)
  95 {
  96         int i, j;
  97         caa_cycles_t time1, time2;
  98
  99         printf("thread_begin %s, tid %lu\n",
 100                 "writer", urcu_get_thread_id());
 101         sleep(2);
 102
 103         for (i = 0; i < OUTER_WRITE_LOOP; i++) {
 104                 for (j = 0; j < INNER_WRITE_LOOP; j++) {
 105                         time1 = caa_get_cycles();
 106                         pthread_rwlock_wrlock(&lock);
 107                         test_array.a = 8;
 108                         pthread_rwlock_unlock(&lock);
 109                         time2 = caa_get_cycles();
 110                         writer_time[(unsigned long)arg] += time2 - time1;
 111                         usleep(1);
 112                 }
 113         }
 114
 115         printf("thread_end %s, tid %lu\n",
 116                 "writer", urcu_get_thread_id());
 117         return ((void*)2);
 118 }
 119
 120 int main(int argc, char **argv)
 121 {
 122         int err;
 123         pthread_t *tid_reader, *tid_writer;
 124         void *tret;
 125         int i;
 126         caa_cycles_t tot_rtime = 0;
 127         caa_cycles_t tot_wtime = 0;
 128
 129         if (argc < 2) {
 130                 printf("Usage : %s nr_readers nr_writers\n", argv[0]);
 131                 exit(-1);
 132         }
 133         num_read = atoi(argv[1]);
 134         num_write = atoi(argv[2]);
 135
 136         reader_time = calloc(num_read, sizeof(*reader_time));
 137         writer_time = calloc(num_write, sizeof(*writer_time));
 138         tid_reader = calloc(num_read, sizeof(*tid_reader));
 139         tid_writer = calloc(num_write, sizeof(*tid_writer));
 140
 141         printf("thread %-6s, tid %lu\n",
 142                 "main", urcu_get_thread_id());
 143
 144         for (i = 0; i < NR_READ; i++) {
 145                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 146                                      (void *)(long)i);
 147                 if (err != 0)
 148                         exit(1);
 149         }
 150         for (i = 0; i < NR_WRITE; i++) {
 151                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 152                                      (void *)(long)i);
 153                 if (err != 0)
 154                         exit(1);
 155         }
 156
 157         sleep(10);
 158
 159         for (i = 0; i < NR_READ; i++) {
 160                 err = pthread_join(tid_reader[i], &tret);
 161                 if (err != 0)
 162                         exit(1);
 163                 tot_rtime += reader_time[i];
 164         }
 165         for (i = 0; i < NR_WRITE; i++) {
 166                 err = pthread_join(tid_writer[i], &tret);
 167                 if (err != 0)
 168                         exit(1);
 169                 tot_wtime += writer_time[i];
 170         }
 171         printf("Time per read : %g cycles\n",
 172                (double)tot_rtime / ((double)NR_READ * (double)READ_LOOP));
 173         printf("Time per write : %g cycles\n",
 174                (double)tot_wtime / ((double)NR_WRITE * (double)WRITE_LOOP));
 175
 176         free(reader_time);
 177         free(writer_time);
 178         free(tid_reader);
 179         free(tid_writer);
 180
 181         return 0;
 182 }