xref: /kernel/linux/linux-5.10/lib/test_min_heap.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-only
2#define pr_fmt(fmt) "min_heap_test: " fmt
3
4/*
5 * Test cases for the min max heap.
6 */
7
8#include <linux/log2.h>
9#include <linux/min_heap.h>
10#include <linux/module.h>
11#include <linux/printk.h>
12#include <linux/random.h>
13
14static __init bool less_than(const void *lhs, const void *rhs)
15{
16	return *(int *)lhs < *(int *)rhs;
17}
18
19static __init bool greater_than(const void *lhs, const void *rhs)
20{
21	return *(int *)lhs > *(int *)rhs;
22}
23
24static __init void swap_ints(void *lhs, void *rhs)
25{
26	int temp = *(int *)lhs;
27
28	*(int *)lhs = *(int *)rhs;
29	*(int *)rhs = temp;
30}
31
32static __init int pop_verify_heap(bool min_heap,
33				struct min_heap *heap,
34				const struct min_heap_callbacks *funcs)
35{
36	int *values = heap->data;
37	int err = 0;
38	int last;
39
40	last = values[0];
41	min_heap_pop(heap, funcs);
42	while (heap->nr > 0) {
43		if (min_heap) {
44			if (last > values[0]) {
45				pr_err("error: expected %d <= %d\n", last,
46					values[0]);
47				err++;
48			}
49		} else {
50			if (last < values[0]) {
51				pr_err("error: expected %d >= %d\n", last,
52					values[0]);
53				err++;
54			}
55		}
56		last = values[0];
57		min_heap_pop(heap, funcs);
58	}
59	return err;
60}
61
62static __init int test_heapify_all(bool min_heap)
63{
64	int values[] = { 3, 1, 2, 4, 0x8000000, 0x7FFFFFF, 0,
65			 -3, -1, -2, -4, 0x8000000, 0x7FFFFFF };
66	struct min_heap heap = {
67		.data = values,
68		.nr = ARRAY_SIZE(values),
69		.size =  ARRAY_SIZE(values),
70	};
71	struct min_heap_callbacks funcs = {
72		.elem_size = sizeof(int),
73		.less = min_heap ? less_than : greater_than,
74		.swp = swap_ints,
75	};
76	int i, err;
77
78	/* Test with known set of values. */
79	min_heapify_all(&heap, &funcs);
80	err = pop_verify_heap(min_heap, &heap, &funcs);
81
82
83	/* Test with randomly generated values. */
84	heap.nr = ARRAY_SIZE(values);
85	for (i = 0; i < heap.nr; i++)
86		values[i] = get_random_int();
87
88	min_heapify_all(&heap, &funcs);
89	err += pop_verify_heap(min_heap, &heap, &funcs);
90
91	return err;
92}
93
94static __init int test_heap_push(bool min_heap)
95{
96	const int data[] = { 3, 1, 2, 4, 0x80000000, 0x7FFFFFFF, 0,
97			     -3, -1, -2, -4, 0x80000000, 0x7FFFFFFF };
98	int values[ARRAY_SIZE(data)];
99	struct min_heap heap = {
100		.data = values,
101		.nr = 0,
102		.size =  ARRAY_SIZE(values),
103	};
104	struct min_heap_callbacks funcs = {
105		.elem_size = sizeof(int),
106		.less = min_heap ? less_than : greater_than,
107		.swp = swap_ints,
108	};
109	int i, temp, err;
110
111	/* Test with known set of values copied from data. */
112	for (i = 0; i < ARRAY_SIZE(data); i++)
113		min_heap_push(&heap, &data[i], &funcs);
114
115	err = pop_verify_heap(min_heap, &heap, &funcs);
116
117	/* Test with randomly generated values. */
118	while (heap.nr < heap.size) {
119		temp = get_random_int();
120		min_heap_push(&heap, &temp, &funcs);
121	}
122	err += pop_verify_heap(min_heap, &heap, &funcs);
123
124	return err;
125}
126
127static __init int test_heap_pop_push(bool min_heap)
128{
129	const int data[] = { 3, 1, 2, 4, 0x80000000, 0x7FFFFFFF, 0,
130			     -3, -1, -2, -4, 0x80000000, 0x7FFFFFFF };
131	int values[ARRAY_SIZE(data)];
132	struct min_heap heap = {
133		.data = values,
134		.nr = 0,
135		.size =  ARRAY_SIZE(values),
136	};
137	struct min_heap_callbacks funcs = {
138		.elem_size = sizeof(int),
139		.less = min_heap ? less_than : greater_than,
140		.swp = swap_ints,
141	};
142	int i, temp, err;
143
144	/* Fill values with data to pop and replace. */
145	temp = min_heap ? 0x80000000 : 0x7FFFFFFF;
146	for (i = 0; i < ARRAY_SIZE(data); i++)
147		min_heap_push(&heap, &temp, &funcs);
148
149	/* Test with known set of values copied from data. */
150	for (i = 0; i < ARRAY_SIZE(data); i++)
151		min_heap_pop_push(&heap, &data[i], &funcs);
152
153	err = pop_verify_heap(min_heap, &heap, &funcs);
154
155	heap.nr = 0;
156	for (i = 0; i < ARRAY_SIZE(data); i++)
157		min_heap_push(&heap, &temp, &funcs);
158
159	/* Test with randomly generated values. */
160	for (i = 0; i < ARRAY_SIZE(data); i++) {
161		temp = get_random_int();
162		min_heap_pop_push(&heap, &temp, &funcs);
163	}
164	err += pop_verify_heap(min_heap, &heap, &funcs);
165
166	return err;
167}
168
169static int __init test_min_heap_init(void)
170{
171	int err = 0;
172
173	err += test_heapify_all(true);
174	err += test_heapify_all(false);
175	err += test_heap_push(true);
176	err += test_heap_push(false);
177	err += test_heap_pop_push(true);
178	err += test_heap_pop_push(false);
179	if (err) {
180		pr_err("test failed with %d errors\n", err);
181		return -EINVAL;
182	}
183	pr_info("test passed\n");
184	return 0;
185}
186module_init(test_min_heap_init);
187
188static void __exit test_min_heap_exit(void)
189{
190	/* do nothing */
191}
192module_exit(test_min_heap_exit);
193
194MODULE_LICENSE("GPL");
195