lib/test_vmalloc.c

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This source file includes following definitions.
test_report_one_done
random_size_align_alloc_test
align_shift_alloc_test
fix_align_alloc_test
random_size_alloc_test
long_busy_list_alloc_test
full_fit_alloc_test
fix_size_alloc_test
pcpu_alloc_test
shuffle_array
test_func
init_test_configurtion
do_concurrent_test
vmalloc_test_init
vmalloc_test_exit
   1 // SPDX-License-Identifier: GPL-2.0
   2 
   3 /*
   4  * Test module for stress and analyze performance of vmalloc allocator.
   5  * (C) 2018 Uladzislau Rezki (Sony) <urezki@gmail.com>
   6  */
   7 #include <linux/init.h>
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/vmalloc.h>
  11 #include <linux/random.h>
  12 #include <linux/kthread.h>
  13 #include <linux/moduleparam.h>
  14 #include <linux/completion.h>
  15 #include <linux/delay.h>
  16 #include <linux/rwsem.h>
  17 #include <linux/mm.h>
  18 
  19 #define __param(type, name, init, msg)          \
  20         static type name = init;                                \
  21         module_param(name, type, 0444);                 \
  22         MODULE_PARM_DESC(name, msg)                             \
  23 
  24 __param(bool, single_cpu_test, false,
  25         "Use single first online CPU to run tests");
  26 
  27 __param(bool, sequential_test_order, false,
  28         "Use sequential stress tests order");
  29 
  30 __param(int, test_repeat_count, 1,
  31         "Set test repeat counter");
  32 
  33 __param(int, test_loop_count, 1000000,
  34         "Set test loop counter");
  35 
  36 __param(int, run_test_mask, INT_MAX,
  37         "Set tests specified in the mask.\n\n"
  38                 "\t\tid: 1,   name: fix_size_alloc_test\n"
  39                 "\t\tid: 2,   name: full_fit_alloc_test\n"
  40                 "\t\tid: 4,   name: long_busy_list_alloc_test\n"
  41                 "\t\tid: 8,   name: random_size_alloc_test\n"
  42                 "\t\tid: 16,  name: fix_align_alloc_test\n"
  43                 "\t\tid: 32,  name: random_size_align_alloc_test\n"
  44                 "\t\tid: 64,  name: align_shift_alloc_test\n"
  45                 "\t\tid: 128, name: pcpu_alloc_test\n"
  46                 /* Add a new test case description here. */
  47 );
  48 
  49 /*
  50  * Depends on single_cpu_test parameter. If it is true, then
  51  * use first online CPU to trigger a test on, otherwise go with
  52  * all online CPUs.
  53  */
  54 static cpumask_t cpus_run_test_mask = CPU_MASK_NONE;
  55 
  56 /*
  57  * Read write semaphore for synchronization of setup
  58  * phase that is done in main thread and workers.
  59  */
  60 static DECLARE_RWSEM(prepare_for_test_rwsem);
  61 
  62 /*
  63  * Completion tracking for worker threads.
  64  */
  65 static DECLARE_COMPLETION(test_all_done_comp);
  66 static atomic_t test_n_undone = ATOMIC_INIT(0);
  67 
  68 static inline void
  69 test_report_one_done(void)
  70 {
  71         if (atomic_dec_and_test(&test_n_undone))
  72                 complete(&test_all_done_comp);
  73 }
  74 
  75 static int random_size_align_alloc_test(void)
  76 {
  77         unsigned long size, align, rnd;
  78         void *ptr;
  79         int i;
  80 
  81         for (i = 0; i < test_loop_count; i++) {
  82                 get_random_bytes(&rnd, sizeof(rnd));
  83 
  84                 /*
  85                  * Maximum 1024 pages, if PAGE_SIZE is 4096.
  86                  */
  87                 align = 1 << (rnd % 23);
  88 
  89                 /*
  90                  * Maximum 10 pages.
  91                  */
  92                 size = ((rnd % 10) + 1) * PAGE_SIZE;
  93 
  94                 ptr = __vmalloc_node_range(size, align,
  95                    VMALLOC_START, VMALLOC_END,
  96                    GFP_KERNEL | __GFP_ZERO,
  97                    PAGE_KERNEL,
  98                    0, 0, __builtin_return_address(0));
  99 
 100                 if (!ptr)
 101                         return -1;
 102 
 103                 vfree(ptr);
 104         }
 105 
 106         return 0;
 107 }
 108 
 109 /*
 110  * This test case is supposed to be failed.
 111  */
 112 static int align_shift_alloc_test(void)
 113 {
 114         unsigned long align;
 115         void *ptr;
 116         int i;
 117 
 118         for (i = 0; i < BITS_PER_LONG; i++) {
 119                 align = ((unsigned long) 1) << i;
 120 
 121                 ptr = __vmalloc_node_range(PAGE_SIZE, align,
 122                         VMALLOC_START, VMALLOC_END,
 123                         GFP_KERNEL | __GFP_ZERO,
 124                         PAGE_KERNEL,
 125                         0, 0, __builtin_return_address(0));
 126 
 127                 if (!ptr)
 128                         return -1;
 129 
 130                 vfree(ptr);
 131         }
 132 
 133         return 0;
 134 }
 135 
 136 static int fix_align_alloc_test(void)
 137 {
 138         void *ptr;
 139         int i;
 140 
 141         for (i = 0; i < test_loop_count; i++) {
 142                 ptr = __vmalloc_node_range(5 * PAGE_SIZE,
 143                         THREAD_ALIGN << 1,
 144                         VMALLOC_START, VMALLOC_END,
 145                         GFP_KERNEL | __GFP_ZERO,
 146                         PAGE_KERNEL,
 147                         0, 0, __builtin_return_address(0));
 148 
 149                 if (!ptr)
 150                         return -1;
 151 
 152                 vfree(ptr);
 153         }
 154 
 155         return 0;
 156 }
 157 
 158 static int random_size_alloc_test(void)
 159 {
 160         unsigned int n;
 161         void *p;
 162         int i;
 163 
 164         for (i = 0; i < test_loop_count; i++) {
 165                 get_random_bytes(&n, sizeof(i));
 166                 n = (n % 100) + 1;
 167 
 168                 p = vmalloc(n * PAGE_SIZE);
 169 
 170                 if (!p)
 171                         return -1;
 172 
 173                 *((__u8 *)p) = 1;
 174                 vfree(p);
 175         }
 176 
 177         return 0;
 178 }
 179 
 180 static int long_busy_list_alloc_test(void)
 181 {
 182         void *ptr_1, *ptr_2;
 183         void **ptr;
 184         int rv = -1;
 185         int i;
 186 
 187         ptr = vmalloc(sizeof(void *) * 15000);
 188         if (!ptr)
 189                 return rv;
 190 
 191         for (i = 0; i < 15000; i++)
 192                 ptr[i] = vmalloc(1 * PAGE_SIZE);
 193 
 194         for (i = 0; i < test_loop_count; i++) {
 195                 ptr_1 = vmalloc(100 * PAGE_SIZE);
 196                 if (!ptr_1)
 197                         goto leave;
 198 
 199                 ptr_2 = vmalloc(1 * PAGE_SIZE);
 200                 if (!ptr_2) {
 201                         vfree(ptr_1);
 202                         goto leave;
 203                 }
 204 
 205                 *((__u8 *)ptr_1) = 0;
 206                 *((__u8 *)ptr_2) = 1;
 207 
 208                 vfree(ptr_1);
 209                 vfree(ptr_2);
 210         }
 211 
 212         /*  Success */
 213         rv = 0;
 214 
 215 leave:
 216         for (i = 0; i < 15000; i++)
 217                 vfree(ptr[i]);
 218 
 219         vfree(ptr);
 220         return rv;
 221 }
 222 
 223 static int full_fit_alloc_test(void)
 224 {
 225         void **ptr, **junk_ptr, *tmp;
 226         int junk_length;
 227         int rv = -1;
 228         int i;
 229 
 230         junk_length = fls(num_online_cpus());
 231         junk_length *= (32 * 1024 * 1024 / PAGE_SIZE);
 232 
 233         ptr = vmalloc(sizeof(void *) * junk_length);
 234         if (!ptr)
 235                 return rv;
 236 
 237         junk_ptr = vmalloc(sizeof(void *) * junk_length);
 238         if (!junk_ptr) {
 239                 vfree(ptr);
 240                 return rv;
 241         }
 242 
 243         for (i = 0; i < junk_length; i++) {
 244                 ptr[i] = vmalloc(1 * PAGE_SIZE);
 245                 junk_ptr[i] = vmalloc(1 * PAGE_SIZE);
 246         }
 247 
 248         for (i = 0; i < junk_length; i++)
 249                 vfree(junk_ptr[i]);
 250 
 251         for (i = 0; i < test_loop_count; i++) {
 252                 tmp = vmalloc(1 * PAGE_SIZE);
 253 
 254                 if (!tmp)
 255                         goto error;
 256 
 257                 *((__u8 *)tmp) = 1;
 258                 vfree(tmp);
 259         }
 260 
 261         /* Success */
 262         rv = 0;
 263 
 264 error:
 265         for (i = 0; i < junk_length; i++)
 266                 vfree(ptr[i]);
 267 
 268         vfree(ptr);
 269         vfree(junk_ptr);
 270 
 271         return rv;
 272 }
 273 
 274 static int fix_size_alloc_test(void)
 275 {
 276         void *ptr;
 277         int i;
 278 
 279         for (i = 0; i < test_loop_count; i++) {
 280                 ptr = vmalloc(3 * PAGE_SIZE);
 281 
 282                 if (!ptr)
 283                         return -1;
 284 
 285                 *((__u8 *)ptr) = 0;
 286 
 287                 vfree(ptr);
 288         }
 289 
 290         return 0;
 291 }
 292 
 293 static int
 294 pcpu_alloc_test(void)
 295 {
 296         int rv = 0;
 297 #ifndef CONFIG_NEED_PER_CPU_KM
 298         void __percpu **pcpu;
 299         size_t size, align;
 300         int i;
 301 
 302         pcpu = vmalloc(sizeof(void __percpu *) * 35000);
 303         if (!pcpu)
 304                 return -1;
 305 
 306         for (i = 0; i < 35000; i++) {
 307                 unsigned int r;
 308 
 309                 get_random_bytes(&r, sizeof(i));
 310                 size = (r % (PAGE_SIZE / 4)) + 1;
 311 
 312                 /*
 313                  * Maximum PAGE_SIZE
 314                  */
 315                 get_random_bytes(&r, sizeof(i));
 316                 align = 1 << ((i % 11) + 1);
 317 
 318                 pcpu[i] = __alloc_percpu(size, align);
 319                 if (!pcpu[i])
 320                         rv = -1;
 321         }
 322 
 323         for (i = 0; i < 35000; i++)
 324                 free_percpu(pcpu[i]);
 325 
 326         vfree(pcpu);
 327 #endif
 328         return rv;
 329 }
 330 
 331 struct test_case_desc {
 332         const char *test_name;
 333         int (*test_func)(void);
 334 };
 335 
 336 static struct test_case_desc test_case_array[] = {
 337         { "fix_size_alloc_test", fix_size_alloc_test },
 338         { "full_fit_alloc_test", full_fit_alloc_test },
 339         { "long_busy_list_alloc_test", long_busy_list_alloc_test },
 340         { "random_size_alloc_test", random_size_alloc_test },
 341         { "fix_align_alloc_test", fix_align_alloc_test },
 342         { "random_size_align_alloc_test", random_size_align_alloc_test },
 343         { "align_shift_alloc_test", align_shift_alloc_test },
 344         { "pcpu_alloc_test", pcpu_alloc_test },
 345         /* Add a new test case here. */
 346 };
 347 
 348 struct test_case_data {
 349         int test_failed;
 350         int test_passed;
 351         u64 time;
 352 };
 353 
 354 /* Split it to get rid of: WARNING: line over 80 characters */
 355 static struct test_case_data
 356         per_cpu_test_data[NR_CPUS][ARRAY_SIZE(test_case_array)];
 357 
 358 static struct test_driver {
 359         struct task_struct *task;
 360         unsigned long start;
 361         unsigned long stop;
 362         int cpu;
 363 } per_cpu_test_driver[NR_CPUS];
 364 
 365 static void shuffle_array(int *arr, int n)
 366 {
 367         unsigned int rnd;
 368         int i, j, x;
 369 
 370         for (i = n - 1; i > 0; i--)  {
 371                 get_random_bytes(&rnd, sizeof(rnd));
 372 
 373                 /* Cut the range. */
 374                 j = rnd % i;
 375 
 376                 /* Swap indexes. */
 377                 x = arr[i];
 378                 arr[i] = arr[j];
 379                 arr[j] = x;
 380         }
 381 }
 382 
 383 static int test_func(void *private)
 384 {
 385         struct test_driver *t = private;
 386         int random_array[ARRAY_SIZE(test_case_array)];
 387         int index, i, j;
 388         ktime_t kt;
 389         u64 delta;
 390 
 391         if (set_cpus_allowed_ptr(current, cpumask_of(t->cpu)) < 0)
 392                 pr_err("Failed to set affinity to %d CPU\n", t->cpu);
 393 
 394         for (i = 0; i < ARRAY_SIZE(test_case_array); i++)
 395                 random_array[i] = i;
 396 
 397         if (!sequential_test_order)
 398                 shuffle_array(random_array, ARRAY_SIZE(test_case_array));
 399 
 400         /*
 401          * Block until initialization is done.
 402          */
 403         down_read(&prepare_for_test_rwsem);
 404 
 405         t->start = get_cycles();
 406         for (i = 0; i < ARRAY_SIZE(test_case_array); i++) {
 407                 index = random_array[i];
 408 
 409                 /*
 410                  * Skip tests if run_test_mask has been specified.
 411                  */
 412                 if (!((run_test_mask & (1 << index)) >> index))
 413                         continue;
 414 
 415                 kt = ktime_get();
 416                 for (j = 0; j < test_repeat_count; j++) {
 417                         if (!test_case_array[index].test_func())
 418                                 per_cpu_test_data[t->cpu][index].test_passed++;
 419                         else
 420                                 per_cpu_test_data[t->cpu][index].test_failed++;
 421                 }
 422 
 423                 /*
 424                  * Take an average time that test took.
 425                  */
 426                 delta = (u64) ktime_us_delta(ktime_get(), kt);
 427                 do_div(delta, (u32) test_repeat_count);
 428 
 429                 per_cpu_test_data[t->cpu][index].time = delta;
 430         }
 431         t->stop = get_cycles();
 432 
 433         up_read(&prepare_for_test_rwsem);
 434         test_report_one_done();
 435 
 436         /*
 437          * Wait for the kthread_stop() call.
 438          */
 439         while (!kthread_should_stop())
 440                 msleep(10);
 441 
 442         return 0;
 443 }
 444 
 445 static void
 446 init_test_configurtion(void)
 447 {
 448         /*
 449          * Reset all data of all CPUs.
 450          */
 451         memset(per_cpu_test_data, 0, sizeof(per_cpu_test_data));
 452 
 453         if (single_cpu_test)
 454                 cpumask_set_cpu(cpumask_first(cpu_online_mask),
 455                         &cpus_run_test_mask);
 456         else
 457                 cpumask_and(&cpus_run_test_mask, cpu_online_mask,
 458                         cpu_online_mask);
 459 
 460         if (test_repeat_count <= 0)
 461                 test_repeat_count = 1;
 462 
 463         if (test_loop_count <= 0)
 464                 test_loop_count = 1;
 465 }
 466 
 467 static void do_concurrent_test(void)
 468 {
 469         int cpu, ret;
 470 
 471         /*
 472          * Set some basic configurations plus sanity check.
 473          */
 474         init_test_configurtion();
 475 
 476         /*
 477          * Put on hold all workers.
 478          */
 479         down_write(&prepare_for_test_rwsem);
 480 
 481         for_each_cpu(cpu, &cpus_run_test_mask) {
 482                 struct test_driver *t = &per_cpu_test_driver[cpu];
 483 
 484                 t->cpu = cpu;
 485                 t->task = kthread_run(test_func, t, "vmalloc_test/%d", cpu);
 486 
 487                 if (!IS_ERR(t->task))
 488                         /* Success. */
 489                         atomic_inc(&test_n_undone);
 490                 else
 491                         pr_err("Failed to start kthread for %d CPU\n", cpu);
 492         }
 493 
 494         /*
 495          * Now let the workers do their job.
 496          */
 497         up_write(&prepare_for_test_rwsem);
 498 
 499         /*
 500          * Sleep quiet until all workers are done with 1 second
 501          * interval. Since the test can take a lot of time we
 502          * can run into a stack trace of the hung task. That is
 503          * why we go with completion_timeout and HZ value.
 504          */
 505         do {
 506                 ret = wait_for_completion_timeout(&test_all_done_comp, HZ);
 507         } while (!ret);
 508 
 509         for_each_cpu(cpu, &cpus_run_test_mask) {
 510                 struct test_driver *t = &per_cpu_test_driver[cpu];
 511                 int i;
 512 
 513                 if (!IS_ERR(t->task))
 514                         kthread_stop(t->task);
 515 
 516                 for (i = 0; i < ARRAY_SIZE(test_case_array); i++) {
 517                         if (!((run_test_mask & (1 << i)) >> i))
 518                                 continue;
 519 
 520                         pr_info(
 521                                 "Summary: %s passed: %d failed: %d repeat: %d loops: %d avg: %llu usec\n",
 522                                 test_case_array[i].test_name,
 523                                 per_cpu_test_data[cpu][i].test_passed,
 524                                 per_cpu_test_data[cpu][i].test_failed,
 525                                 test_repeat_count, test_loop_count,
 526                                 per_cpu_test_data[cpu][i].time);
 527                 }
 528 
 529                 pr_info("All test took CPU%d=%lu cycles\n",
 530                         cpu, t->stop - t->start);
 531         }
 532 }
 533 
 534 static int vmalloc_test_init(void)
 535 {
 536         do_concurrent_test();
 537         return -EAGAIN; /* Fail will directly unload the module */
 538 }
 539 
 540 static void vmalloc_test_exit(void)
 541 {
 542 }
 543 
 544 module_init(vmalloc_test_init)
 545 module_exit(vmalloc_test_exit)
 546 
 547 MODULE_LICENSE("GPL");
 548 MODULE_AUTHOR("Uladzislau Rezki");
 549 MODULE_DESCRIPTION("vmalloc test module");
/* [<][>][^][v][top][bottom][index][help] */
root/lib/test_vmalloc.c

DEFINITIONS
