1 // SPDX-License-Identifier: GPL-2.0-only 2 #define pr_fmt(fmt) "list_sort_test: " fmt 3 4 #include <linux/kernel.h> 5 #include <linux/list_sort.h> 6 #include <linux/list.h> 7 #include <linux/module.h> 8 #include <linux/printk.h> 9 #include <linux/slab.h> 10 #include <linux/random.h> 11 12 /* 13 * The pattern of set bits in the list length determines which cases 14 * are hit in list_sort(). 15 */ 16 #define TEST_LIST_LEN (512+128+2) /* not including head */ 17 18 #define TEST_POISON1 0xDEADBEEF 19 #define TEST_POISON2 0xA324354C 20 21 struct debug_el { 22 unsigned int poison1; 23 struct list_head list; 24 unsigned int poison2; 25 int value; 26 unsigned serial; 27 }; 28 29 /* Array, containing pointers to all elements in the test list */ 30 static struct debug_el **elts __initdata; 31 32 static int __init check(struct debug_el *ela, struct debug_el *elb) 33 { 34 if (ela->serial >= TEST_LIST_LEN) { 35 pr_err("error: incorrect serial %d\n", ela->serial); 36 return -EINVAL; 37 } 38 if (elb->serial >= TEST_LIST_LEN) { 39 pr_err("error: incorrect serial %d\n", elb->serial); 40 return -EINVAL; 41 } 42 if (elts[ela->serial] != ela || elts[elb->serial] != elb) { 43 pr_err("error: phantom element\n"); 44 return -EINVAL; 45 } 46 if (ela->poison1 != TEST_POISON1 || ela->poison2 != TEST_POISON2) { 47 pr_err("error: bad poison: %#x/%#x\n", 48 ela->poison1, ela->poison2); 49 return -EINVAL; 50 } 51 if (elb->poison1 != TEST_POISON1 || elb->poison2 != TEST_POISON2) { 52 pr_err("error: bad poison: %#x/%#x\n", 53 elb->poison1, elb->poison2); 54 return -EINVAL; 55 } 56 return 0; 57 } 58 59 static int __init cmp(void *priv, const struct list_head *a, 60 const struct list_head *b) 61 { 62 struct debug_el *ela, *elb; 63 64 ela = container_of(a, struct debug_el, list); 65 elb = container_of(b, struct debug_el, list); 66 67 check(ela, elb); 68 return ela->value - elb->value; 69 } 70 71 static int __init list_sort_test(void) 72 { 73 int i, count = 1, err = -ENOMEM; 74 struct debug_el *el; 75 struct list_head *cur; 76 LIST_HEAD(head); 77 78 pr_debug("start testing list_sort()\n"); 79 80 elts = kcalloc(TEST_LIST_LEN, sizeof(*elts), GFP_KERNEL); 81 if (!elts) 82 return err; 83 84 for (i = 0; i < TEST_LIST_LEN; i++) { 85 el = kmalloc(sizeof(*el), GFP_KERNEL); 86 if (!el) 87 goto exit; 88 89 /* force some equivalencies */ 90 el->value = prandom_u32() % (TEST_LIST_LEN / 3); 91 el->serial = i; 92 el->poison1 = TEST_POISON1; 93 el->poison2 = TEST_POISON2; 94 elts[i] = el; 95 list_add_tail(&el->list, &head); 96 } 97 98 list_sort(NULL, &head, cmp); 99 100 err = -EINVAL; 101 for (cur = head.next; cur->next != &head; cur = cur->next) { 102 struct debug_el *el1; 103 int cmp_result; 104 105 if (cur->next->prev != cur) { 106 pr_err("error: list is corrupted\n"); 107 goto exit; 108 } 109 110 cmp_result = cmp(NULL, cur, cur->next); 111 if (cmp_result > 0) { 112 pr_err("error: list is not sorted\n"); 113 goto exit; 114 } 115 116 el = container_of(cur, struct debug_el, list); 117 el1 = container_of(cur->next, struct debug_el, list); 118 if (cmp_result == 0 && el->serial >= el1->serial) { 119 pr_err("error: order of equivalent elements not " 120 "preserved\n"); 121 goto exit; 122 } 123 124 if (check(el, el1)) { 125 pr_err("error: element check failed\n"); 126 goto exit; 127 } 128 count++; 129 } 130 if (head.prev != cur) { 131 pr_err("error: list is corrupted\n"); 132 goto exit; 133 } 134 135 136 if (count != TEST_LIST_LEN) { 137 pr_err("error: bad list length %d", count); 138 goto exit; 139 } 140 141 err = 0; 142 exit: 143 for (i = 0; i < TEST_LIST_LEN; i++) 144 kfree(elts[i]); 145 kfree(elts); 146 return err; 147 } 148 module_init(list_sort_test); 149 MODULE_LICENSE("GPL"); 150