xref: /linux/lib/test_min_heap.c (revision d6053666ef2b6631ef8f265f49ff2cc0f4d45c50)
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 
14 static __init bool less_than(const void *lhs, const void *rhs)
15 {
16 	return *(int *)lhs < *(int *)rhs;
17 }
18 
19 static __init bool greater_than(const void *lhs, const void *rhs)
20 {
21 	return *(int *)lhs > *(int *)rhs;
22 }
23 
24 static __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 
32 static __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 
62 static __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_u32();
87 
88 	min_heapify_all(&heap, &funcs);
89 	err += pop_verify_heap(min_heap, &heap, &funcs);
90 
91 	return err;
92 }
93 
94 static __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_u32();
120 		min_heap_push(&heap, &temp, &funcs);
121 	}
122 	err += pop_verify_heap(min_heap, &heap, &funcs);
123 
124 	return err;
125 }
126 
127 static __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_u32();
162 		min_heap_pop_push(&heap, &temp, &funcs);
163 	}
164 	err += pop_verify_heap(min_heap, &heap, &funcs);
165 
166 	return err;
167 }
168 
169 static 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 }
186 module_init(test_min_heap_init);
187 
188 static void __exit test_min_heap_exit(void)
189 {
190 	/* do nothing */
191 }
192 module_exit(test_min_heap_exit);
193 
194 MODULE_LICENSE("GPL");
195