LXR linux/lib/test_list

   1// SPDX-License-Identifier: GPL-2.0-only
   2#include <kunit/test.h>
   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
  21struct debug_el {
  22        unsigned int poison1;
  23        struct list_head list;
  24        unsigned int poison2;
  25        int value;
  26        unsigned int serial;
  27};
  28
  29static void check(struct kunit *test, struct debug_el *ela, struct debug_el *elb)
  30{
  31        struct debug_el **elts = test->priv;
  32
  33        KUNIT_EXPECT_LT_MSG(test, ela->serial, (unsigned int)TEST_LIST_LEN, "incorrect serial");
  34        KUNIT_EXPECT_LT_MSG(test, elb->serial, (unsigned int)TEST_LIST_LEN, "incorrect serial");
  35
  36        KUNIT_EXPECT_PTR_EQ_MSG(test, elts[ela->serial], ela, "phantom element");
  37        KUNIT_EXPECT_PTR_EQ_MSG(test, elts[elb->serial], elb, "phantom element");
  38
  39        KUNIT_EXPECT_EQ_MSG(test, ela->poison1, TEST_POISON1, "bad poison");
  40        KUNIT_EXPECT_EQ_MSG(test, ela->poison2, TEST_POISON2, "bad poison");
  41
  42        KUNIT_EXPECT_EQ_MSG(test, elb->poison1, TEST_POISON1, "bad poison");
  43        KUNIT_EXPECT_EQ_MSG(test, elb->poison2, TEST_POISON2, "bad poison");
  44}
  45
  46/* `priv` is the test pointer so check() can fail the test if the list is invalid. */
  47static int cmp(void *priv, const struct list_head *a, const struct list_head *b)
  48{
  49        struct debug_el *ela, *elb;
  50
  51        ela = container_of(a, struct debug_el, list);
  52        elb = container_of(b, struct debug_el, list);
  53
  54        check(priv, ela, elb);
  55        return ela->value - elb->value;
  56}
  57
  58static void list_sort_test(struct kunit *test)
  59{
  60        int i, count = 1;
  61        struct debug_el *el, **elts;
  62        struct list_head *cur;
  63        LIST_HEAD(head);
  64
  65        elts = kunit_kcalloc(test, TEST_LIST_LEN, sizeof(*elts), GFP_KERNEL);
  66        KUNIT_ASSERT_NOT_ERR_OR_NULL(test, elts);
  67        test->priv = elts;
  68
  69        for (i = 0; i < TEST_LIST_LEN; i++) {
  70                el = kunit_kmalloc(test, sizeof(*el), GFP_KERNEL);
  71                KUNIT_ASSERT_NOT_ERR_OR_NULL(test, el);
  72
  73                 /* force some equivalencies */
  74                el->value = prandom_u32() % (TEST_LIST_LEN / 3);
  75                el->serial = i;
  76                el->poison1 = TEST_POISON1;
  77                el->poison2 = TEST_POISON2;
  78                elts[i] = el;
  79                list_add_tail(&el->list, &head);
  80        }
  81
  82        list_sort(test, &head, cmp);
  83
  84        for (cur = head.next; cur->next != &head; cur = cur->next) {
  85                struct debug_el *el1;
  86                int cmp_result;
  87
  88                KUNIT_ASSERT_PTR_EQ_MSG(test, cur->next->prev, cur,
  89                                        "list is corrupted");
  90
  91                cmp_result = cmp(test, cur, cur->next);
  92                KUNIT_ASSERT_LE_MSG(test, cmp_result, 0, "list is not sorted");
  93
  94                el = container_of(cur, struct debug_el, list);
  95                el1 = container_of(cur->next, struct debug_el, list);
  96                if (cmp_result == 0) {
  97                        KUNIT_ASSERT_LE_MSG(test, el->serial, el1->serial,
  98                                            "order of equivalent elements not preserved");
  99                }
 100
 101                check(test, el, el1);
 102                count++;
 103        }
 104        KUNIT_EXPECT_PTR_EQ_MSG(test, head.prev, cur, "list is corrupted");
 105
 106        KUNIT_EXPECT_EQ_MSG(test, count, TEST_LIST_LEN,
 107                            "list length changed after sorting!");
 108}
 109
 110static struct kunit_case list_sort_cases[] = {
 111        KUNIT_CASE(list_sort_test),
 112        {}
 113};
 114
 115static struct kunit_suite list_sort_suite = {
 116        .name = "list_sort",
 117        .test_cases = list_sort_cases,
 118};
 119
 120kunit_test_suites(&list_sort_suite);
 121
 122MODULE_LICENSE("GPL");
 123