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