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