[PATCH 3/6] lib/list_sort: test: use generic random32

Artem Bityutskiy
2010-08-07T08:11:52Z

From: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
---
lib/list_sort.c | 27 +++++++++++++++------------
1 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/lib/list_sort.c b/lib/list_sort.c
index e0c2ccb..8600e8f 100644
--- a/lib/list_sort.c
+++ b/lib/list_sort.c
@@ -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;
--
1.7.1.1