Expand CONFIG_DEBUG_LIST to several other list operations

When list debugging is enabled, we aim to readably show list corruption
errors, and the basic list_add/list_del operations end up having extra
debugging code in them to do some basic validation of the list entries.

However, "list_del_init()" and "list_move[_tail]()" ended up avoiding
the debug code due to how they were written. This fixes that.

So the _next_ time we have list_move() problems with stale list entries,
we'll hopefully have an easier time finding them..

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds
2011-02-18 11:32:28 -08:00
parent 2a324ce7b7
commit 3c18d4de86
2 changed files with 35 additions and 16 deletions

View File

@@ -35,6 +35,31 @@ void __list_add(struct list_head *new,
}
EXPORT_SYMBOL(__list_add);
void __list_del_entry(struct list_head *entry)
{
struct list_head *prev, *next;
prev = entry->prev;
next = entry->next;
if (WARN(next == LIST_POISON1,
"list_del corruption, %p->next is LIST_POISON1 (%p)\n",
entry, LIST_POISON1) ||
WARN(prev == LIST_POISON2,
"list_del corruption, %p->prev is LIST_POISON2 (%p)\n",
entry, LIST_POISON2) ||
WARN(prev->next != entry,
"list_del corruption. prev->next should be %p, "
"but was %p\n", entry, prev->next) ||
WARN(next->prev != entry,
"list_del corruption. next->prev should be %p, "
"but was %p\n", entry, next->prev))
return;
__list_del(prev, next);
}
EXPORT_SYMBOL(__list_del_entry);
/**
* list_del - deletes entry from list.
* @entry: the element to delete from the list.
@@ -43,19 +68,7 @@ EXPORT_SYMBOL(__list_add);
*/
void list_del(struct list_head *entry)
{
WARN(entry->next == LIST_POISON1,
"list_del corruption, next is LIST_POISON1 (%p)\n",
LIST_POISON1);
WARN(entry->next != LIST_POISON1 && entry->prev == LIST_POISON2,
"list_del corruption, prev is LIST_POISON2 (%p)\n",
LIST_POISON2);
WARN(entry->prev->next != entry,
"list_del corruption. prev->next should be %p, "
"but was %p\n", entry, entry->prev->next);
WARN(entry->next->prev != entry,
"list_del corruption. next->prev should be %p, "
"but was %p\n", entry, entry->next->prev);
__list_del(entry->prev, entry->next);
__list_del_entry(entry);
entry->next = LIST_POISON1;
entry->prev = LIST_POISON2;
}