Commit eeee9ebb authored by Artem Bityutskiy's avatar Artem Bityutskiy Committed by Linus Torvalds
Browse files

lib/list_sort: test: use generic random32 



Instead of using own pseudo-random generator, use generic linux
'random32()' function.  Presumably, this should improve test coverage.

At the same time, do the following changes:
  o Use shorter macro name for test list length
  o Do not use strange 'l_h' name for 'struct list_head' element,
    use 'list', because it is traditional name and thus, makes the
    code more obvious and readable.

Signed-off-by: default avatarArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: Don Mullis <don.mullis@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent bb2ab10f

lib/list_sort.c

+15 −12
Original line number Diff line number Diff line
@@ -142,42 +142,45 @@ void list_sort(void *priv, struct list_head *head, 
EXPORT_SYMBOL(list_sort);



#ifdef CONFIG_TEST_LIST_SORT



#include <linux/random.h>



struct debug_el {

	struct list_head l_h;

	struct list_head list;

	int value;

	unsigned serial;

};



static int cmp(void *priv, struct list_head *a, struct list_head *b)

{

	return container_of(a, struct debug_el, l_h)->value

	     - container_of(b, struct debug_el, l_h)->value;

	return container_of(a, struct debug_el, list)->value

	     - container_of(b, struct debug_el, list)->value;

}



/*

 * The pattern of set bits in the list length determines which cases

 * are hit in list_sort().

 */

#define LIST_SORT_TEST_LENGTH (512+128+2) /* not including head */

#define TEST_LIST_LEN (512+128+2) /* not including head */



static int __init list_sort_test(void)

{

	int i, r = 1, count;

	int i, count;

	struct list_head *head = kmalloc(sizeof(*head), GFP_KERNEL);

	struct list_head *cur;



	printk(KERN_DEBUG "testing list_sort()\n");



	cur = head;

	for (i = 0; i < LIST_SORT_TEST_LENGTH; i++) {

	for (i = 0; i < TEST_LIST_LEN; i++) {

		struct debug_el *el = kmalloc(sizeof(*el), GFP_KERNEL);

		BUG_ON(!el);

		 /* force some equivalencies */

		el->value = (r = (r * 725861) % 6599) % (LIST_SORT_TEST_LENGTH/3);

		el->value = random32() % (TEST_LIST_LEN/3);

		el->serial = i;



		el->l_h.prev = cur;

		cur->next = &el->l_h;

		el->list.prev = cur;

		cur->next = &el->list;

		cur = cur->next;

	}

	head->prev = cur;
@@ -186,7 +189,7 @@ static int __init list_sort_test(void) 


	count = 1;

	for (cur = head->next; cur->next != head; cur = cur->next) {

		struct debug_el *el = container_of(cur, struct debug_el, l_h);

		struct debug_el *el = container_of(cur, struct debug_el, list);

		int cmp_result = cmp(NULL, cur, cur->next);

		if (cur->next->prev != cur) {

			printk(KERN_ERR "list_sort() returned "
@@ -197,7 +200,7 @@ static int __init list_sort_test(void) 
			return 1;

		} else if (cmp_result == 0 &&

				el->serial >= container_of(cur->next,

					struct debug_el, l_h)->serial) {

					struct debug_el, list)->serial) {

			printk(KERN_ERR "list_sort() failed to preserve order "

					"of equivalent elements!\n");

			return 1;
@@ -206,7 +209,7 @@ static int __init list_sort_test(void) 
		count++;

	}

	kfree(cur);

	if (count != LIST_SORT_TEST_LENGTH) {

	if (count != TEST_LIST_LEN) {

		printk(KERN_ERR "list_sort() returned list of "

				"different length!\n");

		return 1;

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