df89a86463
A list_del() debugging check. Has been in -mm for years. Dave moved list_del() out-of-line in the debug case, so this is now suitable for mainline. Cc: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
79 lines
2 KiB
C
79 lines
2 KiB
C
/*
|
|
* Copyright 2006, Red Hat, Inc., Dave Jones
|
|
* Released under the General Public License (GPL).
|
|
*
|
|
* This file contains the linked list implementations for
|
|
* DEBUG_LIST.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/list.h>
|
|
|
|
/*
|
|
* Insert a new entry between two known consecutive entries.
|
|
*
|
|
* This is only for internal list manipulation where we know
|
|
* the prev/next entries already!
|
|
*/
|
|
|
|
void __list_add(struct list_head *new,
|
|
struct list_head *prev,
|
|
struct list_head *next)
|
|
{
|
|
if (unlikely(next->prev != prev)) {
|
|
printk(KERN_ERR "list_add corruption. next->prev should be %p, but was %p\n",
|
|
prev, next->prev);
|
|
BUG();
|
|
}
|
|
if (unlikely(prev->next != next)) {
|
|
printk(KERN_ERR "list_add corruption. prev->next should be %p, but was %p\n",
|
|
next, prev->next);
|
|
BUG();
|
|
}
|
|
next->prev = new;
|
|
new->next = next;
|
|
new->prev = prev;
|
|
prev->next = new;
|
|
}
|
|
EXPORT_SYMBOL(__list_add);
|
|
|
|
/**
|
|
* list_add - add a new entry
|
|
* @new: new entry to be added
|
|
* @head: list head to add it after
|
|
*
|
|
* Insert a new entry after the specified head.
|
|
* This is good for implementing stacks.
|
|
*/
|
|
void list_add(struct list_head *new, struct list_head *head)
|
|
{
|
|
__list_add(new, head, head->next);
|
|
}
|
|
EXPORT_SYMBOL(list_add);
|
|
|
|
/**
|
|
* list_del - deletes entry from list.
|
|
* @entry: the element to delete from the list.
|
|
* Note: list_empty on entry does not return true after this, the entry is
|
|
* in an undefined state.
|
|
*/
|
|
void list_del(struct list_head *entry)
|
|
{
|
|
BUG_ON(entry->prev->next != entry);
|
|
BUG_ON(entry->next->prev != entry);
|
|
|
|
if (unlikely(entry->prev->next != entry)) {
|
|
printk(KERN_ERR "list_del corruption. prev->next should be %p, "
|
|
"but was %p\n", entry, entry->prev->next);
|
|
BUG();
|
|
}
|
|
if (unlikely(entry->next->prev != entry)) {
|
|
printk(KERN_ERR "list_del corruption. next->prev should be %p, "
|
|
"but was %p\n", entry, entry->next->prev);
|
|
BUG();
|
|
}
|
|
__list_del(entry->prev, entry->next);
|
|
entry->next = LIST_POISON1;
|
|
entry->prev = LIST_POISON2;
|
|
}
|
|
EXPORT_SYMBOL(list_del);
|