Print the other (hopefully) known good pointer when list_head debugging too, which may yield additional clues. Also fix for 80-columns to win akpm brownie points. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
		
			
				
	
	
		
			78 lines
		
	
	
	
		
			2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			78 lines
		
	
	
	
		
			2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Copyright 2006, Red Hat, Inc., Dave Jones
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 * Released under the General Public License (GPL).
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 *
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 * This file contains the linked list implementations for
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 * DEBUG_LIST.
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 */
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#include <linux/module.h>
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#include <linux/list.h>
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/*
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 * Insert a new entry between two known consecutive entries.
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 *
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 * This is only for internal list manipulation where we know
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 * the prev/next entries already!
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 */
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void __list_add(struct list_head *new,
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			      struct list_head *prev,
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			      struct list_head *next)
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{
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	if (unlikely(next->prev != prev)) {
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		printk(KERN_ERR "list_add corruption. next->prev should be "
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			"prev (%p), but was %p. (next=%p).\n",
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			prev, next->prev, next);
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		BUG();
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	}
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	if (unlikely(prev->next != next)) {
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		printk(KERN_ERR "list_add corruption. prev->next should be "
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			"next (%p), but was %p. (prev=%p).\n",
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			next, prev->next, prev);
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		BUG();
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	}
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	next->prev = new;
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	new->next = next;
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	new->prev = prev;
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	prev->next = new;
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}
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EXPORT_SYMBOL(__list_add);
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/**
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 * list_add - add a new entry
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 * @new: new entry to be added
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 * @head: list head to add it after
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 *
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 * Insert a new entry after the specified head.
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 * This is good for implementing stacks.
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 */
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void list_add(struct list_head *new, struct list_head *head)
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{
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	__list_add(new, head, head->next);
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}
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EXPORT_SYMBOL(list_add);
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/**
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 * list_del - deletes entry from list.
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 * @entry: the element to delete from the list.
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 * Note: list_empty on entry does not return true after this, the entry is
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 * in an undefined state.
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 */
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void list_del(struct list_head *entry)
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{
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	if (unlikely(entry->prev->next != entry)) {
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		printk(KERN_ERR "list_del corruption. prev->next should be %p, "
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				"but was %p\n", entry, entry->prev->next);
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		BUG();
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	}
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	if (unlikely(entry->next->prev != entry)) {
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		printk(KERN_ERR "list_del corruption. next->prev should be %p, "
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				"but was %p\n", entry, entry->next->prev);
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		BUG();
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	}
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	__list_del(entry->prev, entry->next);
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	entry->next = LIST_POISON1;
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	entry->prev = LIST_POISON2;
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}
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EXPORT_SYMBOL(list_del);
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