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1// SPDX-License-Identifier: GPL-2.02 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 setup62 * phase that is done in main thread and workers.63 */64static DECLARE_RWSEM(prepare_for_test_rwsem);65 66/*67 * Completion tracking for worker threads.68 */69static DECLARE_COMPLETION(test_all_done_comp);70static atomic_t test_n_undone = ATOMIC_INIT(0);71 72static inline void73test_report_one_done(void)74{75 if (atomic_dec_and_test(&test_n_undone))76 complete(&test_all_done_comp);77}78 79static 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 */113static 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 = 1UL << 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 133static 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 151static 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 171static 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 206leave:207 for (i = 0; i < 15000; i++)208 vfree(ptr[i]);209 210 vfree(ptr);211 return rv;212}213 214static 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 255error: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 265static 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 else274 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 287static int288pcpu_alloc_test(void)289{290 int rv = 0;291#ifndef CONFIG_NEED_PER_CPU_KM292 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_SIZE305 */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#endif318 return rv;319}320 321struct test_kvfree_rcu {322 struct rcu_head rcu;323 unsigned char array[20];324};325 326static int327kvfree_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 344static int345kvfree_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 362static int363vm_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 = kcalloc(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 387cleanup: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 397struct test_case_desc {398 const char *test_name;399 int (*test_func)(void);400};401 402static 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 417struct test_case_data {418 int test_failed;419 int test_passed;420 u64 time;421};422 423static 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 431static 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 444static 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 else478 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 503static int504init_test_configuration(void)505{506 /*507 * A maximum number of workers is defined as hard-coded508 * value and set to USHRT_MAX. We add such gap just in509 * 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 527static 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_configuration();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 else552 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 second562 * interval. Since the test can take a lot of time we563 * can run into a stack trace of the hung task. That is564 * 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 597static int vmalloc_test_init(void)598{599 do_concurrent_test();600 return -EAGAIN; /* Fail will directly unload the module */601}602 603module_init(vmalloc_test_init)604 605MODULE_LICENSE("GPL");606MODULE_AUTHOR("Uladzislau Rezki");607MODULE_DESCRIPTION("vmalloc test module");608