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: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Cc: Don Mullis <don.mullis@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/lib/list_sort.c b/lib/list_sort.c
index 679b3a0..8f3c244 100644 (file)
--- 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;