From 199a9afc3dbe98c35326f1d3907ab94dae953a6e Mon Sep 17 00:00:00 2001 From: Dave Jones Date: Fri, 29 Sep 2006 01:59:00 -0700 Subject: [PATCH] Debug variants of linked list macros Signed-off-by: Dave Jones Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/list_debug.c | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 77 insertions(+) create mode 100644 lib/list_debug.c (limited to 'lib/list_debug.c') diff --git a/lib/list_debug.c b/lib/list_debug.c new file mode 100644 index 00000000000..1aae85cef92 --- /dev/null +++ b/lib/list_debug.c @@ -0,0 +1,77 @@ +/* + * 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 +#include + +/* + * 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) +{ + 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); + -- cgit v1.2.3-70-g09d2 From df89a864631f5d840f4873c4c03733b4206e78ea Mon Sep 17 00:00:00 2001 From: Manfred Spraul Date: Fri, 29 Sep 2006 01:59:01 -0700 Subject: [PATCH] list_del debug check 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 Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/list_debug.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'lib/list_debug.c') diff --git a/lib/list_debug.c b/lib/list_debug.c index 1aae85cef92..e80d27c9789 100644 --- a/lib/list_debug.c +++ b/lib/list_debug.c @@ -59,14 +59,17 @@ EXPORT_SYMBOL(list_add); */ 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); + 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); + 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); @@ -74,4 +77,3 @@ void list_del(struct list_head *entry) entry->prev = LIST_POISON2; } EXPORT_SYMBOL(list_del); - -- cgit v1.2.3-70-g09d2