app/test/test_spinlock.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 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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  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 <rte_common.h>
  42 #include <rte_memory.h>
  43 #include <rte_memzone.h>
  44 #include <rte_per_lcore.h>
  45 #include <rte_launch.h>
  46 #include <rte_eal.h>
  47 #include <rte_per_lcore.h>
  48 #include <rte_lcore.h>
  49 #include <rte_cycles.h>
  50 #include <rte_spinlock.h>
  51 #include <rte_atomic.h>
  52
  53 #include "test.h"
  54
  55 /*
  56  * Spinlock test
  57  * =============
  58  *
  59  * - There is a global spinlock and a table of spinlocks (one per lcore).
  60  *
  61  * - The test function takes all of these locks and launches the
  62  *   ``test_spinlock_per_core()`` function on each core (except the master).
  63  *
  64  *   - The function takes the global lock, display something, then releases
  65  *     the global lock.
  66  *   - The function takes the per-lcore lock, display something, then releases
  67  *     the per-core lock.
  68  *
  69  * - The main function unlocks the per-lcore locks sequentially and
  70  *   waits between each lock. This triggers the display of a message
  71  *   for each core, in the correct order. The autotest script checks that
  72  *   this order is correct.
  73  *
  74  * - A load test is carried out, with all cores attempting to lock a single lock
  75  *   multiple times
  76  */
  77
  78 static rte_spinlock_t sl, sl_try;
  79 static rte_spinlock_t sl_tab[RTE_MAX_LCORE];
  80 static rte_spinlock_recursive_t slr;
  81 static unsigned count = 0;
  82
  83 static rte_atomic32_t synchro;
  84
  85 static int
  86 test_spinlock_per_core(__attribute__((unused)) void *arg)
  87 {
  88         rte_spinlock_lock(&sl);
  89         printf("Global lock taken on core %u\n", rte_lcore_id());
  90         rte_spinlock_unlock(&sl);
  91
  92         rte_spinlock_lock(&sl_tab[rte_lcore_id()]);
  93         printf("Hello from core %u !\n", rte_lcore_id());
  94         rte_spinlock_unlock(&sl_tab[rte_lcore_id()]);
  95
  96         return 0;
  97 }
  98
  99 static int
 100 test_spinlock_recursive_per_core(__attribute__((unused)) void *arg)
 101 {
 102         unsigned id = rte_lcore_id();
 103
 104         rte_spinlock_recursive_lock(&slr);
 105         printf("Global recursive lock taken on core %u - count = %d\n",
 106                id, slr.count);
 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
 114         printf("Hello from within recursive locks from core %u !\n", id);
 115
 116         rte_spinlock_recursive_unlock(&slr);
 117         printf("Global recursive lock released on core %u - count = %d\n",
 118                id, slr.count);
 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
 126         return 0;
 127 }
 128
 129 static rte_spinlock_t lk = RTE_SPINLOCK_INITIALIZER;
 130 static uint64_t lock_count[RTE_MAX_LCORE] = {0};
 131
 132 #define TIME_MS 100
 133
 134 static int
 135 load_loop_fn(void *func_param)
 136 {
 137         uint64_t time_diff = 0, begin;
 138         uint64_t hz = rte_get_timer_hz();
 139         uint64_t lcount = 0;
 140         const int use_lock = *(int*)func_param;
 141         const unsigned lcore = rte_lcore_id();
 142
 143         /* wait synchro for slaves */
 144         if (lcore != rte_get_master_lcore())
 145                 while (rte_atomic32_read(&synchro) == 0);
 146
 147         begin = rte_get_timer_cycles();
 148         while (time_diff < hz * TIME_MS / 1000) {
 149                 if (use_lock)
 150                         rte_spinlock_lock(&lk);
 151                 lcount++;
 152                 if (use_lock)
 153                         rte_spinlock_unlock(&lk);
 154                 /* delay to make lock duty cycle slighlty realistic */
 155                 rte_delay_us(1);
 156                 time_diff = rte_get_timer_cycles() - begin;
 157         }
 158         lock_count[lcore] = lcount;
 159         return 0;
 160 }
 161
 162 static int
 163 test_spinlock_perf(void)
 164 {
 165         unsigned int i;
 166         uint64_t total = 0;
 167         int lock = 0;
 168         const unsigned lcore = rte_lcore_id();
 169
 170         printf("\nTest with no lock on single core...\n");
 171         load_loop_fn(&lock);
 172         printf("Core [%u] count = %"PRIu64"\n", lcore, lock_count[lcore]);
 173         memset(lock_count, 0, sizeof(lock_count));
 174
 175         printf("\nTest with lock on single core...\n");
 176         lock = 1;
 177         load_loop_fn(&lock);
 178         printf("Core [%u] count = %"PRIu64"\n", lcore, lock_count[lcore]);
 179         memset(lock_count, 0, sizeof(lock_count));
 180
 181         printf("\nTest with lock on %u cores...\n", rte_lcore_count());
 182
 183         /* Clear synchro and start slaves */
 184         rte_atomic32_set(&synchro, 0);
 185         rte_eal_mp_remote_launch(load_loop_fn, &lock, SKIP_MASTER);
 186
 187         /* start synchro and launch test on master */
 188         rte_atomic32_set(&synchro, 1);
 189         load_loop_fn(&lock);
 190
 191         rte_eal_mp_wait_lcore();
 192
 193         RTE_LCORE_FOREACH(i) {
 194                 printf("Core [%u] count = %"PRIu64"\n", i, lock_count[i]);
 195                 total += lock_count[i];
 196         }
 197
 198         printf("Total count = %"PRIu64"\n", total);
 199
 200         return 0;
 201 }
 202
 203 /*
 204  * Use rte_spinlock_trylock() to trylock a spinlock object,
 205  * If it could not lock the object sucessfully, it would
 206  * return immediately and the variable of "count" would be
 207  * increased by one per times. the value of "count" could be
 208  * checked as the result later.
 209  */
 210 static int
 211 test_spinlock_try(__attribute__((unused)) void *arg)
 212 {
 213         if (rte_spinlock_trylock(&sl_try) == 0) {
 214                 rte_spinlock_lock(&sl);
 215                 count ++;
 216                 rte_spinlock_unlock(&sl);
 217         }
 218
 219         return 0;
 220 }
 221
 222
 223 /*
 224  * Test rte_eal_get_lcore_state() in addition to spinlocks
 225  * as we have "waiting" then "running" lcores.
 226  */
 227 static int
 228 test_spinlock(void)
 229 {
 230         int ret = 0;
 231         int i;
 232
 233         /* slave cores should be waiting: print it */
 234         RTE_LCORE_FOREACH_SLAVE(i) {
 235                 printf("lcore %d state: %d\n", i,
 236                        (int) rte_eal_get_lcore_state(i));
 237         }
 238
 239         rte_spinlock_init(&sl);
 240         rte_spinlock_init(&sl_try);
 241         rte_spinlock_recursive_init(&slr);
 242         for (i=0; i<RTE_MAX_LCORE; i++)
 243                 rte_spinlock_init(&sl_tab[i]);
 244
 245         rte_spinlock_lock(&sl);
 246
 247         RTE_LCORE_FOREACH_SLAVE(i) {
 248                 rte_spinlock_lock(&sl_tab[i]);
 249                 rte_eal_remote_launch(test_spinlock_per_core, NULL, i);
 250         }
 251
 252         /* slave cores should be busy: print it */
 253         RTE_LCORE_FOREACH_SLAVE(i) {
 254                 printf("lcore %d state: %d\n", i,
 255                        (int) rte_eal_get_lcore_state(i));
 256         }
 257         rte_spinlock_unlock(&sl);
 258
 259         RTE_LCORE_FOREACH_SLAVE(i) {
 260                 rte_spinlock_unlock(&sl_tab[i]);
 261                 rte_delay_ms(10);
 262         }
 263
 264         rte_eal_mp_wait_lcore();
 265
 266         rte_spinlock_recursive_lock(&slr);
 267
 268         /*
 269          * Try to acquire a lock that we already own
 270          */
 271         if(!rte_spinlock_recursive_trylock(&slr)) {
 272                 printf("rte_spinlock_recursive_trylock failed on a lock that "
 273                        "we already own\n");
 274                 ret = -1;
 275         } else
 276                 rte_spinlock_recursive_unlock(&slr);
 277
 278         RTE_LCORE_FOREACH_SLAVE(i) {
 279                 rte_eal_remote_launch(test_spinlock_recursive_per_core, NULL, i);
 280         }
 281         rte_spinlock_recursive_unlock(&slr);
 282         rte_eal_mp_wait_lcore();
 283
 284         /*
 285          * Test if it could return immediately from try-locking a locked object.
 286          * Here it will lock the spinlock object first, then launch all the slave
 287          * lcores to trylock the same spinlock object.
 288          * All the slave lcores should give up try-locking a locked object and
 289          * return immediately, and then increase the "count" initialized with zero
 290          * by one per times.
 291          * We can check if the "count" is finally equal to the number of all slave
 292          * lcores to see if the behavior of try-locking a locked spinlock object
 293          * is correct.
 294          */
 295         if (rte_spinlock_trylock(&sl_try) == 0) {
 296                 return -1;
 297         }
 298         count = 0;
 299         RTE_LCORE_FOREACH_SLAVE(i) {
 300                 rte_eal_remote_launch(test_spinlock_try, NULL, i);
 301         }
 302         rte_eal_mp_wait_lcore();
 303         rte_spinlock_unlock(&sl_try);
 304         if (rte_spinlock_is_locked(&sl)) {
 305                 printf("spinlock is locked but it should not be\n");
 306                 return -1;
 307         }
 308         rte_spinlock_lock(&sl);
 309         if (count != ( rte_lcore_count() - 1)) {
 310                 ret = -1;
 311         }
 312         rte_spinlock_unlock(&sl);
 313
 314         /*
 315          * Test if it can trylock recursively.
 316          * Use rte_spinlock_recursive_trylock() to check if it can lock a spinlock
 317          * object recursively. Here it will try to lock a spinlock object twice.
 318          */
 319         if (rte_spinlock_recursive_trylock(&slr) == 0) {
 320                 printf("It failed to do the first spinlock_recursive_trylock but it should able to do\n");
 321                 return -1;
 322         }
 323         if (rte_spinlock_recursive_trylock(&slr) == 0) {
 324                 printf("It failed to do the second spinlock_recursive_trylock but it should able to do\n");
 325                 return -1;
 326         }
 327         rte_spinlock_recursive_unlock(&slr);
 328         rte_spinlock_recursive_unlock(&slr);
 329
 330         if (test_spinlock_perf() < 0)
 331                 return -1;
 332
 333         return ret;
 334 }
 335
 336 static struct test_command spinlock_cmd = {
 337         .command = "spinlock_autotest",
 338         .callback = test_spinlock,
 339 };
 340 REGISTER_TEST_COMMAND(spinlock_cmd);