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 <pthread.h>
  32 #include <errno.h>
  33
  34 #include <urcu/arch.h>
  35 #include <urcu/assert.h>
  36
  37 #include "thread-id.h"
  38
  39 #include <urcu.h>
  40
  41 struct test_array {
  42         int a;
  43 };
  44
  45 /*
  46  * static rwlock initializer is broken on Cygwin. Use runtime
  47  * initialization.
  48  */
  49 pthread_rwlock_t lock;
  50
  51 static struct test_array test_array = { 8 };
  52
  53 #define OUTER_READ_LOOP 200U
  54 #define INNER_READ_LOOP 100000U
  55 #define READ_LOOP ((unsigned long long)OUTER_READ_LOOP * INNER_READ_LOOP)
  56
  57 #define OUTER_WRITE_LOOP 10U
  58 #define INNER_WRITE_LOOP 200U
  59 #define WRITE_LOOP ((unsigned long long)OUTER_WRITE_LOOP * INNER_WRITE_LOOP)
  60
  61 static int num_read;
  62 static int num_write;
  63
  64 #define NR_READ num_read
  65 #define NR_WRITE num_write
  66
  67 static caa_cycles_t __attribute__((aligned(CAA_CACHE_LINE_SIZE))) *reader_time;
  68 static caa_cycles_t __attribute__((aligned(CAA_CACHE_LINE_SIZE))) *writer_time;
  69
  70 static
  71 void *thr_reader(void *arg)
  72 {
  73         unsigned int i, j;
  74         int ret;
  75         caa_cycles_t time1, time2;
  76
  77         printf("thread_begin %s, tid %lu\n",
  78                 "reader", urcu_get_thread_id());
  79         sleep(2);
  80
  81         time1 = caa_get_cycles();
  82         for (i = 0; i < OUTER_READ_LOOP; i++) {
  83                 for (j = 0; j < INNER_READ_LOOP; j++) {
  84                         ret = pthread_rwlock_rdlock(&lock);
  85                         if (ret) {
  86                                 fprintf(stderr, "reader pthread_rwlock_rdlock: %s\n", strerror(ret));
  87                                 abort();
  88                         }
  89
  90                         urcu_posix_assert(test_array.a == 8);
  91
  92                         ret = pthread_rwlock_unlock(&lock);
  93                         if (ret) {
  94                                 fprintf(stderr, "reader pthread_rwlock_unlock: %s\n", strerror(ret));
  95                                 abort();
  96                         }
  97                 }
  98         }
  99         time2 = caa_get_cycles();
 100
 101         reader_time[(unsigned long)arg] = time2 - time1;
 102
 103         sleep(2);
 104         printf("thread_end %s, tid %lu\n",
 105                 "reader", urcu_get_thread_id());
 106         return ((void*)1);
 107
 108 }
 109
 110 static
 111 void *thr_writer(void *arg)
 112 {
 113         unsigned int i, j;
 114         int ret;
 115         caa_cycles_t time1, time2;
 116
 117         printf("thread_begin %s, tid %lu\n",
 118                 "writer", urcu_get_thread_id());
 119         sleep(2);
 120
 121         for (i = 0; i < OUTER_WRITE_LOOP; i++) {
 122                 for (j = 0; j < INNER_WRITE_LOOP; j++) {
 123                         time1 = caa_get_cycles();
 124                         ret = pthread_rwlock_wrlock(&lock);
 125                         if (ret) {
 126                                 fprintf(stderr, "writer pthread_rwlock_wrlock: %s\n", strerror(ret));
 127                                 abort();
 128                         }
 129
 130                         test_array.a = 8;
 131
 132                         ret = pthread_rwlock_unlock(&lock);
 133                         if (ret) {
 134                                 fprintf(stderr, "writer pthread_rwlock_unlock: %s\n", strerror(ret));
 135                                 abort();
 136                         }
 137
 138                         time2 = caa_get_cycles();
 139                         writer_time[(unsigned long)arg] += time2 - time1;
 140                         usleep(1);
 141                 }
 142         }
 143
 144         printf("thread_end %s, tid %lu\n",
 145                 "writer", urcu_get_thread_id());
 146         return ((void*)2);
 147 }
 148
 149 int main(int argc, char **argv)
 150 {
 151         int err;
 152         pthread_t *tid_reader, *tid_writer;
 153         void *tret;
 154         int i;
 155         caa_cycles_t tot_rtime = 0;
 156         caa_cycles_t tot_wtime = 0;
 157
 158         if (argc < 2) {
 159                 printf("Usage : %s nr_readers nr_writers\n", argv[0]);
 160                 exit(-1);
 161         }
 162         num_read = atoi(argv[1]);
 163         num_write = atoi(argv[2]);
 164
 165         err = pthread_rwlock_init(&lock, NULL);
 166         if (err != 0) {
 167                 fprintf(stderr, "pthread_rwlock_init: (%d) %s\n", err, strerror(err));
 168                 exit(1);
 169         }
 170
 171         reader_time = calloc(num_read, sizeof(*reader_time));
 172         writer_time = calloc(num_write, sizeof(*writer_time));
 173         tid_reader = calloc(num_read, sizeof(*tid_reader));
 174         tid_writer = calloc(num_write, sizeof(*tid_writer));
 175
 176         printf("thread %-6s, tid %lu\n",
 177                 "main", urcu_get_thread_id());
 178
 179         for (i = 0; i < NR_READ; i++) {
 180                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 181                                      (void *)(long)i);
 182                 if (err != 0)
 183                         exit(1);
 184         }
 185         for (i = 0; i < NR_WRITE; i++) {
 186                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 187                                      (void *)(long)i);
 188                 if (err != 0)
 189                         exit(1);
 190         }
 191
 192         sleep(10);
 193
 194         for (i = 0; i < NR_READ; i++) {
 195                 err = pthread_join(tid_reader[i], &tret);
 196                 if (err != 0)
 197                         exit(1);
 198                 tot_rtime += reader_time[i];
 199         }
 200         for (i = 0; i < NR_WRITE; i++) {
 201                 err = pthread_join(tid_writer[i], &tret);
 202                 if (err != 0)
 203                         exit(1);
 204                 tot_wtime += writer_time[i];
 205         }
 206         printf("Time per read : %g cycles\n",
 207                (double)tot_rtime / ((double)NR_READ * (double)READ_LOOP));
 208         printf("Time per write : %g cycles\n",
 209                (double)tot_wtime / ((double)NR_WRITE * (double)WRITE_LOOP));
 210
 211         err = pthread_rwlock_destroy(&lock);
 212         if (err != 0) {
 213                 fprintf(stderr, "pthread_rwlock_destroy: (%d) %s\n", err, strerror(err));
 214                 exit(1);
 215         }
 216         free(reader_time);
 217         free(writer_time);
 218         free(tid_reader);
 219         free(tid_writer);
 220
 221         return 0;
 222 }