tests/test_perthreadlock_timing.c

   1 /*
   2  * test_perthreadloc_timing.c
   3  *
   4  * Per thread locks - test program
   5  *
   6  * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
   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 <sys/syscall.h>
  33 #include <pthread.h>
  34
  35 #include "../arch.h"
  36
  37 /* Make this big enough to include the POWER5+ L3 cacheline size of 256B */
  38 #define CACHE_LINE_SIZE 4096
  39
  40 #if defined(_syscall0)
  41 _syscall0(pid_t, gettid)
  42 #elif defined(__NR_gettid)
  43 static inline pid_t gettid(void)
  44 {
  45         return syscall(__NR_gettid);
  46 }
  47 #else
  48 #warning "use pid as tid"
  49 static inline pid_t gettid(void)
  50 {
  51         return getpid();
  52 }
  53 #endif
  54
  55 #include "../urcu.h"
  56
  57 struct test_array {
  58         int a;
  59 };
  60
  61 static struct test_array test_array = { 8 };
  62
  63 struct per_thread_lock {
  64         pthread_mutex_t lock;
  65 } __attribute__((aligned(CACHE_LINE_SIZE)));    /* cache-line aligned */
  66
  67 static struct per_thread_lock *per_thread_lock;
  68
  69 #define OUTER_READ_LOOP 200U
  70 #define INNER_READ_LOOP 100000U
  71 #define READ_LOOP ((unsigned long long)OUTER_READ_LOOP * INNER_READ_LOOP)
  72
  73 #define OUTER_WRITE_LOOP 10U
  74 #define INNER_WRITE_LOOP 200U
  75 #define WRITE_LOOP ((unsigned long long)OUTER_WRITE_LOOP * INNER_WRITE_LOOP)
  76
  77 static int num_read;
  78 static int num_write;
  79
  80 #define NR_READ num_read
  81 #define NR_WRITE num_write
  82
  83 static cycles_t __attribute__((aligned(CACHE_LINE_SIZE))) *reader_time;
  84 static cycles_t __attribute__((aligned(CACHE_LINE_SIZE))) *writer_time;
  85
  86 void *thr_reader(void *arg)
  87 {
  88         int i, j;
  89         cycles_t time1, time2;
  90         long tidx = (long)arg;
  91
  92         printf("thread_begin %s, thread id : %lx, tid %lu\n",
  93                         "reader", pthread_self(), (unsigned long)gettid());
  94         sleep(2);
  95
  96         time1 = get_cycles();
  97         for (i = 0; i < OUTER_READ_LOOP; i++) {
  98                 for (j = 0; j < INNER_READ_LOOP; j++) {
  99                         pthread_mutex_lock(&per_thread_lock[tidx].lock);
 100                         assert(test_array.a == 8);
 101                         pthread_mutex_unlock(&per_thread_lock[tidx].lock);
 102                 }
 103         }
 104         time2 = get_cycles();
 105
 106         reader_time[tidx] = time2 - time1;
 107
 108         sleep(2);
 109         printf("thread_end %s, thread id : %lx, tid %lu\n",
 110                         "reader", pthread_self(), (unsigned long)gettid());
 111         return ((void*)1);
 112
 113 }
 114
 115 void *thr_writer(void *arg)
 116 {
 117         int i, j;
 118         long tidx;
 119         cycles_t time1, time2;
 120
 121         printf("thread_begin %s, thread id : %lx, tid %lu\n",
 122                         "writer", pthread_self(), (unsigned long)gettid());
 123         sleep(2);
 124
 125         for (i = 0; i < OUTER_WRITE_LOOP; i++) {
 126                 for (j = 0; j < INNER_WRITE_LOOP; j++) {
 127                         time1 = get_cycles();
 128                         for (tidx = 0; tidx < NR_READ; tidx++) {
 129                                 pthread_mutex_lock(&per_thread_lock[tidx].lock);
 130                         }
 131                         test_array.a = 8;
 132                         for (tidx = NR_READ - 1; tidx >= 0; tidx--) {
 133                                 pthread_mutex_unlock(&per_thread_lock[tidx].lock);
 134                         }
 135                         time2 = get_cycles();
 136                         writer_time[(unsigned long)arg] += time2 - time1;
 137                         usleep(1);
 138                 }
 139         }
 140
 141         printf("thread_end %s, thread id : %lx, tid %lu\n",
 142                         "writer", pthread_self(), (unsigned long)gettid());
 143         return ((void*)2);
 144 }
 145
 146 int main(int argc, char **argv)
 147 {
 148         int err;
 149         pthread_t *tid_reader, *tid_writer;
 150         void *tret;
 151         int i;
 152         cycles_t tot_rtime = 0;
 153         cycles_t tot_wtime = 0;
 154
 155         if (argc < 2) {
 156                 printf("Usage : %s nr_readers nr_writers\n", argv[0]);
 157                 exit(-1);
 158         }
 159         num_read = atoi(argv[1]);
 160         num_write = atoi(argv[2]);
 161
 162         reader_time = malloc(sizeof(*reader_time) * num_read);
 163         writer_time = malloc(sizeof(*writer_time) * num_write);
 164         tid_reader = malloc(sizeof(*tid_reader) * num_read);
 165         tid_writer = malloc(sizeof(*tid_writer) * num_write);
 166
 167         printf("thread %-6s, thread id : %lx, tid %lu\n",
 168                         "main", pthread_self(), (unsigned long)gettid());
 169
 170         per_thread_lock = malloc(sizeof(struct per_thread_lock) * NR_READ);
 171
 172         for (i = 0; i < NR_READ; i++) {
 173                 pthread_mutex_init(&per_thread_lock[i].lock, NULL);
 174         }
 175         for (i = 0; i < NR_READ; i++) {
 176                 err = pthread_create(&tid_reader[i], NULL, thr_reader,
 177                                      (void *)(long)i);
 178                 if (err != 0)
 179                         exit(1);
 180         }
 181         for (i = 0; i < NR_WRITE; i++) {
 182                 err = pthread_create(&tid_writer[i], NULL, thr_writer,
 183                                      (void *)(long)i);
 184                 if (err != 0)
 185                         exit(1);
 186         }
 187
 188         sleep(10);
 189
 190         for (i = 0; i < NR_READ; i++) {
 191                 err = pthread_join(tid_reader[i], &tret);
 192                 if (err != 0)
 193                         exit(1);
 194                 tot_rtime += reader_time[i];
 195         }
 196         for (i = 0; i < NR_WRITE; i++) {
 197                 err = pthread_join(tid_writer[i], &tret);
 198                 if (err != 0)
 199                         exit(1);
 200                 tot_wtime += writer_time[i];
 201         }
 202         printf("Time per read : %g cycles\n",
 203                (double)tot_rtime / ((double)NR_READ * (double)READ_LOOP));
 204         printf("Time per write : %g cycles\n",
 205                (double)tot_wtime / ((double)NR_WRITE * (double)WRITE_LOOP));
 206         free(per_thread_lock);
 207
 208         free(reader_time);
 209         free(writer_time);
 210         free(tid_reader);
 211         free(tid_writer);
 212
 213         return 0;
 214 }