ceph/src/spdk/dpdk/test/test/test_atomic.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2014 Intel Corporation
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdint.h>
   7 #include <unistd.h>
   8 #include <sys/queue.h>
   9
  10 #include <rte_memory.h>
  11 #include <rte_per_lcore.h>
  12 #include <rte_launch.h>
  13 #include <rte_atomic.h>
  14 #include <rte_eal.h>
  15 #include <rte_lcore.h>
  16
  17 #include "test.h"
  18
  19 /*
  20  * Atomic Variables
  21  * ================
  22  *
  23  * - The main test function performs three subtests. The first test
  24  *   checks that the usual inc/dec/add/sub functions are working
  25  *   correctly:
  26  *
  27  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to specific
  28  *     values.
  29  *
  30  *   - These variables are incremented and decremented on each core at
  31  *     the same time in ``test_atomic_usual()``.
  32  *
  33  *   - The function checks that once all lcores finish their function,
  34  *     the value of the atomic variables are still the same.
  35  *
  36  * - The second test verifies the behavior of "test and set" functions.
  37  *
  38  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to zero.
  39  *
  40  *   - Invoke ``test_atomic_tas()`` on each lcore: before doing anything
  41  *     else. The cores are waiting a synchro using ``while
  42  *     (rte_atomic32_read(&val) == 0)`` which is triggered by the main test
  43  *     function. Then all cores do a
  44  *     ``rte_atomicXX_test_and_set()`` at the same time. If it is successful,
  45  *     it increments another atomic counter.
  46  *
  47  *   - The main function checks that the atomic counter was incremented
  48  *     twice only (one for 16-bit, one for 32-bit and one for 64-bit values).
  49  *
  50  * - Test "add/sub and return"
  51  *
  52  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to zero.
  53  *
  54  *   - Invoke ``test_atomic_addsub_return()`` on each lcore. Before doing
  55  *     anything else, the cores are waiting a synchro. Each lcore does
  56  *     this operation several times::
  57  *
  58  *       tmp = rte_atomicXX_add_return(&a, 1);
  59  *       atomic_add(&count, tmp);
  60  *       tmp = rte_atomicXX_sub_return(&a, 1);
  61  *       atomic_sub(&count, tmp+1);
  62  *
  63  *   - At the end of the test, the *count* value must be 0.
  64  */
  65
  66 #define NUM_ATOMIC_TYPES 3
  67
  68 #define N 10000
  69
  70 static rte_atomic16_t a16;
  71 static rte_atomic32_t a32;
  72 static rte_atomic64_t a64;
  73 static rte_atomic64_t count;
  74 static rte_atomic32_t synchro;
  75
  76 static int
  77 test_atomic_usual(__attribute__((unused)) void *arg)
  78 {
  79         unsigned i;
  80
  81         while (rte_atomic32_read(&synchro) == 0)
  82                 ;
  83
  84         for (i = 0; i < N; i++)
  85                 rte_atomic16_inc(&a16);
  86         for (i = 0; i < N; i++)
  87                 rte_atomic16_dec(&a16);
  88         for (i = 0; i < (N / 5); i++)
  89                 rte_atomic16_add(&a16, 5);
  90         for (i = 0; i < (N / 5); i++)
  91                 rte_atomic16_sub(&a16, 5);
  92
  93         for (i = 0; i < N; i++)
  94                 rte_atomic32_inc(&a32);
  95         for (i = 0; i < N; i++)
  96                 rte_atomic32_dec(&a32);
  97         for (i = 0; i < (N / 5); i++)
  98                 rte_atomic32_add(&a32, 5);
  99         for (i = 0; i < (N / 5); i++)
 100                 rte_atomic32_sub(&a32, 5);
 101
 102         for (i = 0; i < N; i++)
 103                 rte_atomic64_inc(&a64);
 104         for (i = 0; i < N; i++)
 105                 rte_atomic64_dec(&a64);
 106         for (i = 0; i < (N / 5); i++)
 107                 rte_atomic64_add(&a64, 5);
 108         for (i = 0; i < (N / 5); i++)
 109                 rte_atomic64_sub(&a64, 5);
 110
 111         return 0;
 112 }
 113
 114 static int
 115 test_atomic_tas(__attribute__((unused)) void *arg)
 116 {
 117         while (rte_atomic32_read(&synchro) == 0)
 118                 ;
 119
 120         if (rte_atomic16_test_and_set(&a16))
 121                 rte_atomic64_inc(&count);
 122         if (rte_atomic32_test_and_set(&a32))
 123                 rte_atomic64_inc(&count);
 124         if (rte_atomic64_test_and_set(&a64))
 125                 rte_atomic64_inc(&count);
 126
 127         return 0;
 128 }
 129
 130 static int
 131 test_atomic_addsub_and_return(__attribute__((unused)) void *arg)
 132 {
 133         uint32_t tmp16;
 134         uint32_t tmp32;
 135         uint64_t tmp64;
 136         unsigned i;
 137
 138         while (rte_atomic32_read(&synchro) == 0)
 139                 ;
 140
 141         for (i = 0; i < N; i++) {
 142                 tmp16 = rte_atomic16_add_return(&a16, 1);
 143                 rte_atomic64_add(&count, tmp16);
 144
 145                 tmp16 = rte_atomic16_sub_return(&a16, 1);
 146                 rte_atomic64_sub(&count, tmp16+1);
 147
 148                 tmp32 = rte_atomic32_add_return(&a32, 1);
 149                 rte_atomic64_add(&count, tmp32);
 150
 151                 tmp32 = rte_atomic32_sub_return(&a32, 1);
 152                 rte_atomic64_sub(&count, tmp32+1);
 153
 154                 tmp64 = rte_atomic64_add_return(&a64, 1);
 155                 rte_atomic64_add(&count, tmp64);
 156
 157                 tmp64 = rte_atomic64_sub_return(&a64, 1);
 158                 rte_atomic64_sub(&count, tmp64+1);
 159         }
 160
 161         return 0;
 162 }
 163
 164 /*
 165  * rte_atomic32_inc_and_test() would increase a 32 bits counter by one and then
 166  * test if that counter is equal to 0. It would return true if the counter is 0
 167  * and false if the counter is not 0. rte_atomic64_inc_and_test() could do the
 168  * same thing but for a 64 bits counter.
 169  * Here checks that if the 32/64 bits counter is equal to 0 after being atomically
 170  * increased by one. If it is, increase the variable of "count" by one which would
 171  * be checked as the result later.
 172  *
 173  */
 174 static int
 175 test_atomic_inc_and_test(__attribute__((unused)) void *arg)
 176 {
 177         while (rte_atomic32_read(&synchro) == 0)
 178                 ;
 179
 180         if (rte_atomic16_inc_and_test(&a16)) {
 181                 rte_atomic64_inc(&count);
 182         }
 183         if (rte_atomic32_inc_and_test(&a32)) {
 184                 rte_atomic64_inc(&count);
 185         }
 186         if (rte_atomic64_inc_and_test(&a64)) {
 187                 rte_atomic64_inc(&count);
 188         }
 189
 190         return 0;
 191 }
 192
 193 /*
 194  * rte_atomicXX_dec_and_test() should decrease a 32 bits counter by one and then
 195  * test if that counter is equal to 0. It should return true if the counter is 0
 196  * and false if the counter is not 0.
 197  * This test checks if the counter is equal to 0 after being atomically
 198  * decreased by one. If it is, increase the value of "count" by one which is to
 199  * be checked as the result later.
 200  */
 201 static int
 202 test_atomic_dec_and_test(__attribute__((unused)) void *arg)
 203 {
 204         while (rte_atomic32_read(&synchro) == 0)
 205                 ;
 206
 207         if (rte_atomic16_dec_and_test(&a16))
 208                 rte_atomic64_inc(&count);
 209
 210         if (rte_atomic32_dec_and_test(&a32))
 211                 rte_atomic64_inc(&count);
 212
 213         if (rte_atomic64_dec_and_test(&a64))
 214                 rte_atomic64_inc(&count);
 215
 216         return 0;
 217 }
 218
 219 static int
 220 test_atomic(void)
 221 {
 222         rte_atomic16_init(&a16);
 223         rte_atomic32_init(&a32);
 224         rte_atomic64_init(&a64);
 225         rte_atomic64_init(&count);
 226         rte_atomic32_init(&synchro);
 227
 228         rte_atomic16_set(&a16, 1UL << 10);
 229         rte_atomic32_set(&a32, 1UL << 10);
 230         rte_atomic64_set(&a64, 1ULL << 33);
 231
 232         printf("usual inc/dec/add/sub functions\n");
 233
 234         rte_eal_mp_remote_launch(test_atomic_usual, NULL, SKIP_MASTER);
 235         rte_atomic32_set(&synchro, 1);
 236         rte_eal_mp_wait_lcore();
 237         rte_atomic32_set(&synchro, 0);
 238
 239         if (rte_atomic16_read(&a16) != 1UL << 10) {
 240                 printf("Atomic16 usual functions failed\n");
 241                 return -1;
 242         }
 243
 244         if (rte_atomic32_read(&a32) != 1UL << 10) {
 245                 printf("Atomic32 usual functions failed\n");
 246                 return -1;
 247         }
 248
 249         if (rte_atomic64_read(&a64) != 1ULL << 33) {
 250                 printf("Atomic64 usual functions failed\n");
 251                 return -1;
 252         }
 253
 254         printf("test and set\n");
 255
 256         rte_atomic64_set(&a64, 0);
 257         rte_atomic32_set(&a32, 0);
 258         rte_atomic16_set(&a16, 0);
 259         rte_atomic64_set(&count, 0);
 260         rte_eal_mp_remote_launch(test_atomic_tas, NULL, SKIP_MASTER);
 261         rte_atomic32_set(&synchro, 1);
 262         rte_eal_mp_wait_lcore();
 263         rte_atomic32_set(&synchro, 0);
 264
 265         if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
 266                 printf("Atomic test and set failed\n");
 267                 return -1;
 268         }
 269
 270         printf("add/sub and return\n");
 271
 272         rte_atomic64_set(&a64, 0);
 273         rte_atomic32_set(&a32, 0);
 274         rte_atomic16_set(&a16, 0);
 275         rte_atomic64_set(&count, 0);
 276         rte_eal_mp_remote_launch(test_atomic_addsub_and_return, NULL,
 277                                  SKIP_MASTER);
 278         rte_atomic32_set(&synchro, 1);
 279         rte_eal_mp_wait_lcore();
 280         rte_atomic32_set(&synchro, 0);
 281
 282         if (rte_atomic64_read(&count) != 0) {
 283                 printf("Atomic add/sub+return failed\n");
 284                 return -1;
 285         }
 286
 287         /*
 288          * Set a64, a32 and a16 with the same value of minus "number of slave
 289          * lcores", launch all slave lcores to atomically increase by one and
 290          * test them respectively.
 291          * Each lcore should have only one chance to increase a64 by one and
 292          * then check if it is equal to 0, but there should be only one lcore
 293          * that finds that it is 0. It is similar for a32 and a16.
 294          * Then a variable of "count", initialized to zero, is increased by
 295          * one if a64, a32 or a16 is 0 after being increased and tested
 296          * atomically.
 297          * We can check if "count" is finally equal to 3 to see if all slave
 298          * lcores performed "atomic inc and test" right.
 299          */
 300         printf("inc and test\n");
 301
 302         rte_atomic64_clear(&a64);
 303         rte_atomic32_clear(&a32);
 304         rte_atomic16_clear(&a16);
 305         rte_atomic32_clear(&synchro);
 306         rte_atomic64_clear(&count);
 307
 308         rte_atomic64_set(&a64, (int64_t)(1 - (int64_t)rte_lcore_count()));
 309         rte_atomic32_set(&a32, (int32_t)(1 - (int32_t)rte_lcore_count()));
 310         rte_atomic16_set(&a16, (int16_t)(1 - (int16_t)rte_lcore_count()));
 311         rte_eal_mp_remote_launch(test_atomic_inc_and_test, NULL, SKIP_MASTER);
 312         rte_atomic32_set(&synchro, 1);
 313         rte_eal_mp_wait_lcore();
 314         rte_atomic32_clear(&synchro);
 315
 316         if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
 317                 printf("Atomic inc and test failed %d\n", (int)count.cnt);
 318                 return -1;
 319         }
 320
 321         /*
 322          * Same as above, but this time we set the values to "number of slave
 323          * lcores", and decrement instead of increment.
 324          */
 325         printf("dec and test\n");
 326
 327         rte_atomic32_clear(&synchro);
 328         rte_atomic64_clear(&count);
 329
 330         rte_atomic64_set(&a64, (int64_t)(rte_lcore_count() - 1));
 331         rte_atomic32_set(&a32, (int32_t)(rte_lcore_count() - 1));
 332         rte_atomic16_set(&a16, (int16_t)(rte_lcore_count() - 1));
 333         rte_eal_mp_remote_launch(test_atomic_dec_and_test, NULL, SKIP_MASTER);
 334         rte_atomic32_set(&synchro, 1);
 335         rte_eal_mp_wait_lcore();
 336         rte_atomic32_clear(&synchro);
 337
 338         if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
 339                 printf("Atomic dec and test failed\n");
 340                 return -1;
 341         }
 342
 343         return 0;
 344 }
 345
 346 REGISTER_TEST_COMMAND(atomic_autotest, test_atomic);