app/test/test_spinlock.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2013 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
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   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
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  13  *     * Redistributions in binary form must reproduce the above copyright
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  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
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  19  *       from this software without specific prior written permission.
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  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <stdio.h>
  35 #include <stdint.h>
  36 #include <inttypes.h>
  37 #include <string.h>
  38 #include <unistd.h>
  39 #include <sys/queue.h>
  40
  41 #include <cmdline_parse.h>
  42
  43 #include <rte_common.h>
  44 #include <rte_memory.h>
  45 #include <rte_memzone.h>
  46 #include <rte_per_lcore.h>
  47 #include <rte_launch.h>
  48 #include <rte_tailq.h>
  49 #include <rte_eal.h>
  50 #include <rte_per_lcore.h>
  51 #include <rte_lcore.h>
  52 #include <rte_cycles.h>
  53 #include <rte_spinlock.h>
  54 #include <rte_atomic.h>
  55
  56 #include "test.h"
  57
  58 /*
  59  * Spinlock test
  60  * =============
  61  *
  62  * - There is a global spinlock and a table of spinlocks (one per lcore).
  63  *
  64  * - The test function takes all of these locks and launches the
  65  *   ``test_spinlock_per_core()`` function on each core (except the master).
  66  *
  67  *   - The function takes the global lock, display something, then releases
  68  *     the global lock.
  69  *   - The function takes the per-lcore lock, display something, then releases
  70  *     the per-core lock.
  71  *
  72  * - The main function unlocks the per-lcore locks sequentially and
  73  *   waits between each lock. This triggers the display of a message
  74  *   for each core, in the correct order. The autotest script checks that
  75  *   this order is correct.
  76  *
  77  * - A load test is carried out, with all cores attempting to lock a single lock
  78  *   multiple times
  79  */
  80
  81 static rte_spinlock_t sl, sl_try;
  82 static rte_spinlock_t sl_tab[RTE_MAX_LCORE];
  83 static rte_spinlock_recursive_t slr;
  84 static unsigned count = 0;
  85
  86 static rte_atomic32_t synchro;
  87
  88 static int
  89 test_spinlock_per_core(__attribute__((unused)) void *arg)
  90 {
  91         rte_spinlock_lock(&sl);
  92         printf("Global lock taken on core %u\n", rte_lcore_id());
  93         rte_spinlock_unlock(&sl);
  94
  95         rte_spinlock_lock(&sl_tab[rte_lcore_id()]);
  96         printf("Hello from core %u !\n", rte_lcore_id());
  97         rte_spinlock_unlock(&sl_tab[rte_lcore_id()]);
  98
  99         return 0;
 100 }
 101
 102 static int
 103 test_spinlock_recursive_per_core(__attribute__((unused)) void *arg)
 104 {
 105         unsigned id = rte_lcore_id();
 106
 107         rte_spinlock_recursive_lock(&slr);
 108         printf("Global recursive lock taken on core %u - count = %d\n",
 109                id, slr.count);
 110         rte_spinlock_recursive_lock(&slr);
 111         printf("Global recursive lock taken on core %u - count = %d\n",
 112                id, slr.count);
 113         rte_spinlock_recursive_lock(&slr);
 114         printf("Global recursive lock taken on core %u - count = %d\n",
 115                id, slr.count);
 116
 117         printf("Hello from within recursive locks from core %u !\n", id);
 118
 119         rte_spinlock_recursive_unlock(&slr);
 120         printf("Global recursive lock released on core %u - count = %d\n",
 121                id, slr.count);
 122         rte_spinlock_recursive_unlock(&slr);
 123         printf("Global recursive lock released on core %u - count = %d\n",
 124                id, slr.count);
 125         rte_spinlock_recursive_unlock(&slr);
 126         printf("Global recursive lock released on core %u - count = %d\n",
 127                id, slr.count);
 128
 129         return 0;
 130 }
 131
 132 static rte_spinlock_t lk = RTE_SPINLOCK_INITIALIZER;
 133 static uint64_t lock_count[RTE_MAX_LCORE] = {0};
 134
 135 #define TIME_S 5
 136
 137 static int
 138 load_loop_fn(void *func_param)
 139 {
 140         uint64_t time_diff = 0, begin;
 141         uint64_t hz = rte_get_timer_hz();
 142         uint64_t lcount = 0;
 143         const int use_lock = *(int*)func_param;
 144         const unsigned lcore = rte_lcore_id();
 145
 146         /* wait synchro for slaves */
 147         if (lcore != rte_get_master_lcore())
 148                 while (rte_atomic32_read(&synchro) == 0);
 149
 150         begin = rte_get_timer_cycles();
 151         while (time_diff / hz < TIME_S) {
 152                 if (use_lock)
 153                         rte_spinlock_lock(&lk);
 154                 lcount++;
 155                 if (use_lock)
 156                         rte_spinlock_unlock(&lk);
 157                 /* delay to make lock duty cycle slighlty realistic */
 158                 rte_delay_us(1);
 159                 time_diff = rte_get_timer_cycles() - begin;
 160         }
 161         lock_count[lcore] = lcount;
 162         return 0;
 163 }
 164
 165 static int
 166 test_spinlock_perf(void)
 167 {
 168         unsigned int i;
 169         uint64_t total = 0;
 170         int lock = 0;
 171         const unsigned lcore = rte_lcore_id();
 172
 173         printf("\nTest with no lock on single core...\n");
 174         load_loop_fn(&lock);
 175         printf("Core [%u] count = %"PRIu64"\n", lcore, lock_count[lcore]);
 176         memset(lock_count, 0, sizeof(lock_count));
 177
 178         printf("\nTest with lock on single core...\n");
 179         lock = 1;
 180         load_loop_fn(&lock);
 181         printf("Core [%u] count = %"PRIu64"\n", lcore, lock_count[lcore]);
 182         memset(lock_count, 0, sizeof(lock_count));
 183
 184         printf("\nTest with lock on %u cores...\n", rte_lcore_count());
 185
 186         /* Clear synchro and start slaves */
 187         rte_atomic32_set(&synchro, 0);
 188         rte_eal_mp_remote_launch(load_loop_fn, &lock, SKIP_MASTER);
 189
 190         /* start synchro and launch test on master */
 191         rte_atomic32_set(&synchro, 1);
 192         load_loop_fn(&lock);
 193
 194         rte_eal_mp_wait_lcore();
 195
 196         RTE_LCORE_FOREACH(i) {
 197                 printf("Core [%u] count = %"PRIu64"\n", i, lock_count[i]);
 198                 total += lock_count[i];
 199         }
 200
 201         printf("Total count = %"PRIu64"\n", total);
 202
 203         return 0;
 204 }
 205
 206 /*
 207  * Use rte_spinlock_trylock() to trylock a spinlock object,
 208  * If it could not lock the object sucessfully, it would
 209  * return immediately and the variable of "count" would be
 210  * increased by one per times. the value of "count" could be
 211  * checked as the result later.
 212  */
 213 static int
 214 test_spinlock_try(__attribute__((unused)) void *arg)
 215 {
 216         if (rte_spinlock_trylock(&sl_try) == 0) {
 217                 rte_spinlock_lock(&sl);
 218                 count ++;
 219                 rte_spinlock_unlock(&sl);
 220         }
 221
 222         return 0;
 223 }
 224
 225
 226 /*
 227  * Test rte_eal_get_lcore_state() in addition to spinlocks
 228  * as we have "waiting" then "running" lcores.
 229  */
 230 int
 231 test_spinlock(void)
 232 {
 233         int ret = 0;
 234         int i;
 235
 236         /* slave cores should be waiting: print it */
 237         RTE_LCORE_FOREACH_SLAVE(i) {
 238                 printf("lcore %d state: %d\n", i,
 239                        (int) rte_eal_get_lcore_state(i));
 240         }
 241
 242         rte_spinlock_init(&sl);
 243         rte_spinlock_init(&sl_try);
 244         rte_spinlock_recursive_init(&slr);
 245         for (i=0; i<RTE_MAX_LCORE; i++)
 246                 rte_spinlock_init(&sl_tab[i]);
 247
 248         rte_spinlock_lock(&sl);
 249
 250         RTE_LCORE_FOREACH_SLAVE(i) {
 251                 rte_spinlock_lock(&sl_tab[i]);
 252                 rte_eal_remote_launch(test_spinlock_per_core, NULL, i);
 253         }
 254
 255         /* slave cores should be busy: print it */
 256         RTE_LCORE_FOREACH_SLAVE(i) {
 257                 printf("lcore %d state: %d\n", i,
 258                        (int) rte_eal_get_lcore_state(i));
 259         }
 260         rte_spinlock_unlock(&sl);
 261
 262         RTE_LCORE_FOREACH_SLAVE(i) {
 263                 rte_spinlock_unlock(&sl_tab[i]);
 264                 rte_delay_ms(100);
 265         }
 266
 267         rte_eal_mp_wait_lcore();
 268
 269         rte_spinlock_recursive_lock(&slr);
 270
 271         /*
 272          * Try to acquire a lock that we already own
 273          */
 274         if(!rte_spinlock_recursive_trylock(&slr)) {
 275                 printf("rte_spinlock_recursive_trylock failed on a lock that "
 276                        "we already own\n");
 277                 ret = -1;
 278         } else
 279                 rte_spinlock_recursive_unlock(&slr);
 280
 281         RTE_LCORE_FOREACH_SLAVE(i) {
 282                 rte_eal_remote_launch(test_spinlock_recursive_per_core, NULL, i);
 283         }
 284         rte_spinlock_recursive_unlock(&slr);
 285         rte_eal_mp_wait_lcore();
 286
 287         /*
 288          * Test if it could return immediately from try-locking a locked object.
 289          * Here it will lock the spinlock object first, then launch all the slave
 290          * lcores to trylock the same spinlock object.
 291          * All the slave lcores should give up try-locking a locked object and
 292          * return immediately, and then increase the "count" initialized with zero
 293          * by one per times.
 294          * We can check if the "count" is finally equal to the number of all slave
 295          * lcores to see if the behavior of try-locking a locked spinlock object
 296          * is correct.
 297          */
 298         if (rte_spinlock_trylock(&sl_try) == 0) {
 299                 return -1;
 300         }
 301         count = 0;
 302         RTE_LCORE_FOREACH_SLAVE(i) {
 303                 rte_eal_remote_launch(test_spinlock_try, NULL, i);
 304         }
 305         rte_eal_mp_wait_lcore();
 306         rte_spinlock_unlock(&sl_try);
 307         if (rte_spinlock_is_locked(&sl)) {
 308                 printf("spinlock is locked but it should not be\n");
 309                 return -1;
 310         }
 311         rte_spinlock_lock(&sl);
 312         if (count != ( rte_lcore_count() - 1)) {
 313                 ret = -1;
 314         }
 315         rte_spinlock_unlock(&sl);
 316
 317         /*
 318          * Test if it can trylock recursively.
 319          * Use rte_spinlock_recursive_trylock() to check if it can lock a spinlock
 320          * object recursively. Here it will try to lock a spinlock object twice.
 321          */
 322         if (rte_spinlock_recursive_trylock(&slr) == 0) {
 323                 printf("It failed to do the first spinlock_recursive_trylock but it should able to do\n");
 324                 return -1;
 325         }
 326         if (rte_spinlock_recursive_trylock(&slr) == 0) {
 327                 printf("It failed to do the second spinlock_recursive_trylock but it should able to do\n");
 328                 return -1;
 329         }
 330         rte_spinlock_recursive_unlock(&slr);
 331         rte_spinlock_recursive_unlock(&slr);
 332
 333         if (test_spinlock_perf() < 0)
 334                 return -1;
 335
 336         return ret;
 337 }