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 #include <linux/rcupdate.h> 19 #include <linux/slab.h> 20 21 #define __param(type, name, init, msg) \ 22 static type name = init; \ 23 module_param(name, type, 0444); \ 24 MODULE_PARM_DESC(name, msg) \ 25 26 __param(int, nr_threads, 0, 27 "Number of workers to perform tests(min: 1 max: USHRT_MAX)"); 28 29 __param(bool, sequential_test_order, false, 30 "Use sequential stress tests order"); 31 32 __param(int, test_repeat_count, 1, 33 "Set test repeat counter"); 34 35 __param(int, test_loop_count, 1000000, 36 "Set test loop counter"); 37 38 __param(int, nr_pages, 0, 39 "Set number of pages for fix_size_alloc_test(default: 1)"); 40 41 __param(bool, use_huge, false, 42 "Use vmalloc_huge in fix_size_alloc_test"); 43 44 __param(int, run_test_mask, INT_MAX, 45 "Set tests specified in the mask.\n\n" 46 "\t\tid: 1, name: fix_size_alloc_test\n" 47 "\t\tid: 2, name: full_fit_alloc_test\n" 48 "\t\tid: 4, name: long_busy_list_alloc_test\n" 49 "\t\tid: 8, name: random_size_alloc_test\n" 50 "\t\tid: 16, name: fix_align_alloc_test\n" 51 "\t\tid: 32, name: random_size_align_alloc_test\n" 52 "\t\tid: 64, name: align_shift_alloc_test\n" 53 "\t\tid: 128, name: pcpu_alloc_test\n" 54 "\t\tid: 256, name: kvfree_rcu_1_arg_vmalloc_test\n" 55 "\t\tid: 512, name: kvfree_rcu_2_arg_vmalloc_test\n" 56 "\t\tid: 1024, name: vm_map_ram_test\n" 57 /* Add a new test case description here. */ 58 ); 59 60 /* 61 * Read write semaphore for synchronization of setup 62 * phase that is done in main thread and workers. 63 */ 64 static DECLARE_RWSEM(prepare_for_test_rwsem); 65 66 /* 67 * Completion tracking for worker threads. 68 */ 69 static DECLARE_COMPLETION(test_all_done_comp); 70 static atomic_t test_n_undone = ATOMIC_INIT(0); 71 72 static inline void 73 test_report_one_done(void) 74 { 75 if (atomic_dec_and_test(&test_n_undone)) 76 complete(&test_all_done_comp); 77 } 78 79 static int random_size_align_alloc_test(void) 80 { 81 unsigned long size, align; 82 unsigned int rnd; 83 void *ptr; 84 int i; 85 86 for (i = 0; i < test_loop_count; i++) { 87 rnd = get_random_u8(); 88 89 /* 90 * Maximum 1024 pages, if PAGE_SIZE is 4096. 91 */ 92 align = 1 << (rnd % 23); 93 94 /* 95 * Maximum 10 pages. 96 */ 97 size = ((rnd % 10) + 1) * PAGE_SIZE; 98 99 ptr = __vmalloc_node(size, align, GFP_KERNEL | __GFP_ZERO, 0, 100 __builtin_return_address(0)); 101 if (!ptr) 102 return -1; 103 104 vfree(ptr); 105 } 106 107 return 0; 108 } 109 110 /* 111 * This test case is supposed to be failed. 112 */ 113 static int align_shift_alloc_test(void) 114 { 115 unsigned long align; 116 void *ptr; 117 int i; 118 119 for (i = 0; i < BITS_PER_LONG; i++) { 120 align = ((unsigned long) 1) << i; 121 122 ptr = __vmalloc_node(PAGE_SIZE, align, GFP_KERNEL|__GFP_ZERO, 0, 123 __builtin_return_address(0)); 124 if (!ptr) 125 return -1; 126 127 vfree(ptr); 128 } 129 130 return 0; 131 } 132 133 static int fix_align_alloc_test(void) 134 { 135 void *ptr; 136 int i; 137 138 for (i = 0; i < test_loop_count; i++) { 139 ptr = __vmalloc_node(5 * PAGE_SIZE, THREAD_ALIGN << 1, 140 GFP_KERNEL | __GFP_ZERO, 0, 141 __builtin_return_address(0)); 142 if (!ptr) 143 return -1; 144 145 vfree(ptr); 146 } 147 148 return 0; 149 } 150 151 static int random_size_alloc_test(void) 152 { 153 unsigned int n; 154 void *p; 155 int i; 156 157 for (i = 0; i < test_loop_count; i++) { 158 n = get_random_u32_inclusive(1, 100); 159 p = vmalloc(n * PAGE_SIZE); 160 161 if (!p) 162 return -1; 163 164 *((__u8 *)p) = 1; 165 vfree(p); 166 } 167 168 return 0; 169 } 170 171 static int long_busy_list_alloc_test(void) 172 { 173 void *ptr_1, *ptr_2; 174 void **ptr; 175 int rv = -1; 176 int i; 177 178 ptr = vmalloc(sizeof(void *) * 15000); 179 if (!ptr) 180 return rv; 181 182 for (i = 0; i < 15000; i++) 183 ptr[i] = vmalloc(1 * PAGE_SIZE); 184 185 for (i = 0; i < test_loop_count; i++) { 186 ptr_1 = vmalloc(100 * PAGE_SIZE); 187 if (!ptr_1) 188 goto leave; 189 190 ptr_2 = vmalloc(1 * PAGE_SIZE); 191 if (!ptr_2) { 192 vfree(ptr_1); 193 goto leave; 194 } 195 196 *((__u8 *)ptr_1) = 0; 197 *((__u8 *)ptr_2) = 1; 198 199 vfree(ptr_1); 200 vfree(ptr_2); 201 } 202 203 /* Success */ 204 rv = 0; 205 206 leave: 207 for (i = 0; i < 15000; i++) 208 vfree(ptr[i]); 209 210 vfree(ptr); 211 return rv; 212 } 213 214 static int full_fit_alloc_test(void) 215 { 216 void **ptr, **junk_ptr, *tmp; 217 int junk_length; 218 int rv = -1; 219 int i; 220 221 junk_length = fls(num_online_cpus()); 222 junk_length *= (32 * 1024 * 1024 / PAGE_SIZE); 223 224 ptr = vmalloc(sizeof(void *) * junk_length); 225 if (!ptr) 226 return rv; 227 228 junk_ptr = vmalloc(sizeof(void *) * junk_length); 229 if (!junk_ptr) { 230 vfree(ptr); 231 return rv; 232 } 233 234 for (i = 0; i < junk_length; i++) { 235 ptr[i] = vmalloc(1 * PAGE_SIZE); 236 junk_ptr[i] = vmalloc(1 * PAGE_SIZE); 237 } 238 239 for (i = 0; i < junk_length; i++) 240 vfree(junk_ptr[i]); 241 242 for (i = 0; i < test_loop_count; i++) { 243 tmp = vmalloc(1 * PAGE_SIZE); 244 245 if (!tmp) 246 goto error; 247 248 *((__u8 *)tmp) = 1; 249 vfree(tmp); 250 } 251 252 /* Success */ 253 rv = 0; 254 255 error: 256 for (i = 0; i < junk_length; i++) 257 vfree(ptr[i]); 258 259 vfree(ptr); 260 vfree(junk_ptr); 261 262 return rv; 263 } 264 265 static int fix_size_alloc_test(void) 266 { 267 void *ptr; 268 int i; 269 270 for (i = 0; i < test_loop_count; i++) { 271 if (use_huge) 272 ptr = vmalloc_huge((nr_pages > 0 ? nr_pages:1) * PAGE_SIZE, GFP_KERNEL); 273 else 274 ptr = vmalloc((nr_pages > 0 ? nr_pages:1) * PAGE_SIZE); 275 276 if (!ptr) 277 return -1; 278 279 *((__u8 *)ptr) = 0; 280 281 vfree(ptr); 282 } 283 284 return 0; 285 } 286 287 static int 288 pcpu_alloc_test(void) 289 { 290 int rv = 0; 291 #ifndef CONFIG_NEED_PER_CPU_KM 292 void __percpu **pcpu; 293 size_t size, align; 294 int i; 295 296 pcpu = vmalloc(sizeof(void __percpu *) * 35000); 297 if (!pcpu) 298 return -1; 299 300 for (i = 0; i < 35000; i++) { 301 size = get_random_u32_inclusive(1, PAGE_SIZE / 4); 302 303 /* 304 * Maximum PAGE_SIZE 305 */ 306 align = 1 << get_random_u32_inclusive(1, 11); 307 308 pcpu[i] = __alloc_percpu(size, align); 309 if (!pcpu[i]) 310 rv = -1; 311 } 312 313 for (i = 0; i < 35000; i++) 314 free_percpu(pcpu[i]); 315 316 vfree(pcpu); 317 #endif 318 return rv; 319 } 320 321 struct test_kvfree_rcu { 322 struct rcu_head rcu; 323 unsigned char array[20]; 324 }; 325 326 static int 327 kvfree_rcu_1_arg_vmalloc_test(void) 328 { 329 struct test_kvfree_rcu *p; 330 int i; 331 332 for (i = 0; i < test_loop_count; i++) { 333 p = vmalloc(1 * PAGE_SIZE); 334 if (!p) 335 return -1; 336 337 p->array[0] = 'a'; 338 kvfree_rcu_mightsleep(p); 339 } 340 341 return 0; 342 } 343 344 static int 345 kvfree_rcu_2_arg_vmalloc_test(void) 346 { 347 struct test_kvfree_rcu *p; 348 int i; 349 350 for (i = 0; i < test_loop_count; i++) { 351 p = vmalloc(1 * PAGE_SIZE); 352 if (!p) 353 return -1; 354 355 p->array[0] = 'a'; 356 kvfree_rcu(p, rcu); 357 } 358 359 return 0; 360 } 361 362 static int 363 vm_map_ram_test(void) 364 { 365 unsigned long nr_allocated; 366 unsigned int map_nr_pages; 367 unsigned char *v_ptr; 368 struct page **pages; 369 int i; 370 371 map_nr_pages = nr_pages > 0 ? nr_pages:1; 372 pages = kmalloc(map_nr_pages * sizeof(struct page), GFP_KERNEL); 373 if (!pages) 374 return -1; 375 376 nr_allocated = alloc_pages_bulk_array(GFP_KERNEL, map_nr_pages, pages); 377 if (nr_allocated != map_nr_pages) 378 goto cleanup; 379 380 /* Run the test loop. */ 381 for (i = 0; i < test_loop_count; i++) { 382 v_ptr = vm_map_ram(pages, map_nr_pages, NUMA_NO_NODE); 383 *v_ptr = 'a'; 384 vm_unmap_ram(v_ptr, map_nr_pages); 385 } 386 387 cleanup: 388 for (i = 0; i < nr_allocated; i++) 389 __free_page(pages[i]); 390 391 kfree(pages); 392 393 /* 0 indicates success. */ 394 return nr_allocated != map_nr_pages; 395 } 396 397 struct test_case_desc { 398 const char *test_name; 399 int (*test_func)(void); 400 }; 401 402 static struct test_case_desc test_case_array[] = { 403 { "fix_size_alloc_test", fix_size_alloc_test }, 404 { "full_fit_alloc_test", full_fit_alloc_test }, 405 { "long_busy_list_alloc_test", long_busy_list_alloc_test }, 406 { "random_size_alloc_test", random_size_alloc_test }, 407 { "fix_align_alloc_test", fix_align_alloc_test }, 408 { "random_size_align_alloc_test", random_size_align_alloc_test }, 409 { "align_shift_alloc_test", align_shift_alloc_test }, 410 { "pcpu_alloc_test", pcpu_alloc_test }, 411 { "kvfree_rcu_1_arg_vmalloc_test", kvfree_rcu_1_arg_vmalloc_test }, 412 { "kvfree_rcu_2_arg_vmalloc_test", kvfree_rcu_2_arg_vmalloc_test }, 413 { "vm_map_ram_test", vm_map_ram_test }, 414 /* Add a new test case here. */ 415 }; 416 417 struct test_case_data { 418 int test_failed; 419 int test_passed; 420 u64 time; 421 }; 422 423 static struct test_driver { 424 struct task_struct *task; 425 struct test_case_data data[ARRAY_SIZE(test_case_array)]; 426 427 unsigned long start; 428 unsigned long stop; 429 } *tdriver; 430 431 static void shuffle_array(int *arr, int n) 432 { 433 int i, j; 434 435 for (i = n - 1; i > 0; i--) { 436 /* Cut the range. */ 437 j = get_random_u32_below(i); 438 439 /* Swap indexes. */ 440 swap(arr[i], arr[j]); 441 } 442 } 443 444 static int test_func(void *private) 445 { 446 struct test_driver *t = private; 447 int random_array[ARRAY_SIZE(test_case_array)]; 448 int index, i, j; 449 ktime_t kt; 450 u64 delta; 451 452 for (i = 0; i < ARRAY_SIZE(test_case_array); i++) 453 random_array[i] = i; 454 455 if (!sequential_test_order) 456 shuffle_array(random_array, ARRAY_SIZE(test_case_array)); 457 458 /* 459 * Block until initialization is done. 460 */ 461 down_read(&prepare_for_test_rwsem); 462 463 t->start = get_cycles(); 464 for (i = 0; i < ARRAY_SIZE(test_case_array); i++) { 465 index = random_array[i]; 466 467 /* 468 * Skip tests if run_test_mask has been specified. 469 */ 470 if (!((run_test_mask & (1 << index)) >> index)) 471 continue; 472 473 kt = ktime_get(); 474 for (j = 0; j < test_repeat_count; j++) { 475 if (!test_case_array[index].test_func()) 476 t->data[index].test_passed++; 477 else 478 t->data[index].test_failed++; 479 } 480 481 /* 482 * Take an average time that test took. 483 */ 484 delta = (u64) ktime_us_delta(ktime_get(), kt); 485 do_div(delta, (u32) test_repeat_count); 486 487 t->data[index].time = delta; 488 } 489 t->stop = get_cycles(); 490 491 up_read(&prepare_for_test_rwsem); 492 test_report_one_done(); 493 494 /* 495 * Wait for the kthread_stop() call. 496 */ 497 while (!kthread_should_stop()) 498 msleep(10); 499 500 return 0; 501 } 502 503 static int 504 init_test_configurtion(void) 505 { 506 /* 507 * A maximum number of workers is defined as hard-coded 508 * value and set to USHRT_MAX. We add such gap just in 509 * case and for potential heavy stressing. 510 */ 511 nr_threads = clamp(nr_threads, 1, (int) USHRT_MAX); 512 513 /* Allocate the space for test instances. */ 514 tdriver = kvcalloc(nr_threads, sizeof(*tdriver), GFP_KERNEL); 515 if (tdriver == NULL) 516 return -1; 517 518 if (test_repeat_count <= 0) 519 test_repeat_count = 1; 520 521 if (test_loop_count <= 0) 522 test_loop_count = 1; 523 524 return 0; 525 } 526 527 static void do_concurrent_test(void) 528 { 529 int i, ret; 530 531 /* 532 * Set some basic configurations plus sanity check. 533 */ 534 ret = init_test_configurtion(); 535 if (ret < 0) 536 return; 537 538 /* 539 * Put on hold all workers. 540 */ 541 down_write(&prepare_for_test_rwsem); 542 543 for (i = 0; i < nr_threads; i++) { 544 struct test_driver *t = &tdriver[i]; 545 546 t->task = kthread_run(test_func, t, "vmalloc_test/%d", i); 547 548 if (!IS_ERR(t->task)) 549 /* Success. */ 550 atomic_inc(&test_n_undone); 551 else 552 pr_err("Failed to start %d kthread\n", i); 553 } 554 555 /* 556 * Now let the workers do their job. 557 */ 558 up_write(&prepare_for_test_rwsem); 559 560 /* 561 * Sleep quiet until all workers are done with 1 second 562 * interval. Since the test can take a lot of time we 563 * can run into a stack trace of the hung task. That is 564 * why we go with completion_timeout and HZ value. 565 */ 566 do { 567 ret = wait_for_completion_timeout(&test_all_done_comp, HZ); 568 } while (!ret); 569 570 for (i = 0; i < nr_threads; i++) { 571 struct test_driver *t = &tdriver[i]; 572 int j; 573 574 if (!IS_ERR(t->task)) 575 kthread_stop(t->task); 576 577 for (j = 0; j < ARRAY_SIZE(test_case_array); j++) { 578 if (!((run_test_mask & (1 << j)) >> j)) 579 continue; 580 581 pr_info( 582 "Summary: %s passed: %d failed: %d repeat: %d loops: %d avg: %llu usec\n", 583 test_case_array[j].test_name, 584 t->data[j].test_passed, 585 t->data[j].test_failed, 586 test_repeat_count, test_loop_count, 587 t->data[j].time); 588 } 589 590 pr_info("All test took worker%d=%lu cycles\n", 591 i, t->stop - t->start); 592 } 593 594 kvfree(tdriver); 595 } 596 597 static int vmalloc_test_init(void) 598 { 599 do_concurrent_test(); 600 return -EAGAIN; /* Fail will directly unload the module */ 601 } 602 603 static void vmalloc_test_exit(void) 604 { 605 } 606 607 module_init(vmalloc_test_init) 608 module_exit(vmalloc_test_exit) 609 610 MODULE_LICENSE("GPL"); 611 MODULE_AUTHOR("Uladzislau Rezki"); 612 MODULE_DESCRIPTION("vmalloc test module"); 613