linux/lib/test_min_heap.c
Ian Rogers 6e24628d78 lib: Introduce generic min-heap
Supports push, pop and converting an array into a heap. If the sense of
the compare function is inverted then it can provide a max-heap.

Based-on-work-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-3-irogers@google.com
2020-03-06 11:56:59 +01:00

195 lines
4.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#define pr_fmt(fmt) "min_heap_test: " fmt
/*
* Test cases for the min max heap.
*/
#include <linux/log2.h>
#include <linux/min_heap.h>
#include <linux/module.h>
#include <linux/printk.h>
#include <linux/random.h>
static __init bool less_than(const void *lhs, const void *rhs)
{
return *(int *)lhs < *(int *)rhs;
}
static __init bool greater_than(const void *lhs, const void *rhs)
{
return *(int *)lhs > *(int *)rhs;
}
static __init void swap_ints(void *lhs, void *rhs)
{
int temp = *(int *)lhs;
*(int *)lhs = *(int *)rhs;
*(int *)rhs = temp;
}
static __init int pop_verify_heap(bool min_heap,
struct min_heap *heap,
const struct min_heap_callbacks *funcs)
{
int *values = heap->data;
int err = 0;
int last;
last = values[0];
min_heap_pop(heap, funcs);
while (heap->nr > 0) {
if (min_heap) {
if (last > values[0]) {
pr_err("error: expected %d <= %d\n", last,
values[0]);
err++;
}
} else {
if (last < values[0]) {
pr_err("error: expected %d >= %d\n", last,
values[0]);
err++;
}
}
last = values[0];
min_heap_pop(heap, funcs);
}
return err;
}
static __init int test_heapify_all(bool min_heap)
{
int values[] = { 3, 1, 2, 4, 0x8000000, 0x7FFFFFF, 0,
-3, -1, -2, -4, 0x8000000, 0x7FFFFFF };
struct min_heap heap = {
.data = values,
.nr = ARRAY_SIZE(values),
.size = ARRAY_SIZE(values),
};
struct min_heap_callbacks funcs = {
.elem_size = sizeof(int),
.less = min_heap ? less_than : greater_than,
.swp = swap_ints,
};
int i, err;
/* Test with known set of values. */
min_heapify_all(&heap, &funcs);
err = pop_verify_heap(min_heap, &heap, &funcs);
/* Test with randomly generated values. */
heap.nr = ARRAY_SIZE(values);
for (i = 0; i < heap.nr; i++)
values[i] = get_random_int();
min_heapify_all(&heap, &funcs);
err += pop_verify_heap(min_heap, &heap, &funcs);
return err;
}
static __init int test_heap_push(bool min_heap)
{
const int data[] = { 3, 1, 2, 4, 0x80000000, 0x7FFFFFFF, 0,
-3, -1, -2, -4, 0x80000000, 0x7FFFFFFF };
int values[ARRAY_SIZE(data)];
struct min_heap heap = {
.data = values,
.nr = 0,
.size = ARRAY_SIZE(values),
};
struct min_heap_callbacks funcs = {
.elem_size = sizeof(int),
.less = min_heap ? less_than : greater_than,
.swp = swap_ints,
};
int i, temp, err;
/* Test with known set of values copied from data. */
for (i = 0; i < ARRAY_SIZE(data); i++)
min_heap_push(&heap, &data[i], &funcs);
err = pop_verify_heap(min_heap, &heap, &funcs);
/* Test with randomly generated values. */
while (heap.nr < heap.size) {
temp = get_random_int();
min_heap_push(&heap, &temp, &funcs);
}
err += pop_verify_heap(min_heap, &heap, &funcs);
return err;
}
static __init int test_heap_pop_push(bool min_heap)
{
const int data[] = { 3, 1, 2, 4, 0x80000000, 0x7FFFFFFF, 0,
-3, -1, -2, -4, 0x80000000, 0x7FFFFFFF };
int values[ARRAY_SIZE(data)];
struct min_heap heap = {
.data = values,
.nr = 0,
.size = ARRAY_SIZE(values),
};
struct min_heap_callbacks funcs = {
.elem_size = sizeof(int),
.less = min_heap ? less_than : greater_than,
.swp = swap_ints,
};
int i, temp, err;
/* Fill values with data to pop and replace. */
temp = min_heap ? 0x80000000 : 0x7FFFFFFF;
for (i = 0; i < ARRAY_SIZE(data); i++)
min_heap_push(&heap, &temp, &funcs);
/* Test with known set of values copied from data. */
for (i = 0; i < ARRAY_SIZE(data); i++)
min_heap_pop_push(&heap, &data[i], &funcs);
err = pop_verify_heap(min_heap, &heap, &funcs);
heap.nr = 0;
for (i = 0; i < ARRAY_SIZE(data); i++)
min_heap_push(&heap, &temp, &funcs);
/* Test with randomly generated values. */
for (i = 0; i < ARRAY_SIZE(data); i++) {
temp = get_random_int();
min_heap_pop_push(&heap, &temp, &funcs);
}
err += pop_verify_heap(min_heap, &heap, &funcs);
return err;
}
static int __init test_min_heap_init(void)
{
int err = 0;
err += test_heapify_all(true);
err += test_heapify_all(false);
err += test_heap_push(true);
err += test_heap_push(false);
err += test_heap_pop_push(true);
err += test_heap_pop_push(false);
if (err) {
pr_err("test failed with %d errors\n", err);
return -EINVAL;
}
pr_info("test passed\n");
return 0;
}
module_init(test_min_heap_init);
static void __exit test_min_heap_exit(void)
{
/* do nothing */
}
module_exit(test_min_heap_exit);
MODULE_LICENSE("GPL");