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	 725d704eca
			
		
	
	
		725d704eca
		
	
	
	
	
		
			
			Introduce a VM_BUG_ON, which is turned on with CONFIG_DEBUG_VM. Use this in the lightweight, inline refcounting functions; PageLRU and PageActive checks in vmscan, because they're pretty well confined to vmscan. And in page allocate/free fastpaths which can be the hottest parts of the kernel for kbuilds. Unlike BUG_ON, VM_BUG_ON must not be used to execute statements with side-effects, and should not be used outside core mm code. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Hugh Dickins <hugh@veritas.com> Cc: Christoph Lameter <clameter@engr.sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
		
			
				
	
	
		
			41 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			41 lines
		
	
	
		
			1.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* internal.h: mm/ internal definitions
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|  *
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|  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
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|  * Written by David Howells (dhowells@redhat.com)
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License
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|  * as published by the Free Software Foundation; either version
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|  * 2 of the License, or (at your option) any later version.
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|  */
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| #ifndef __MM_INTERNAL_H
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| #define __MM_INTERNAL_H
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| 
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| #include <linux/mm.h>
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| 
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| static inline void set_page_count(struct page *page, int v)
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| {
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| 	atomic_set(&page->_count, v);
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| }
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| 
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| /*
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|  * Turn a non-refcounted page (->_count == 0) into refcounted with
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|  * a count of one.
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|  */
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| static inline void set_page_refcounted(struct page *page)
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| {
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| 	VM_BUG_ON(PageCompound(page) && page_private(page) != (unsigned long)page);
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| 	VM_BUG_ON(atomic_read(&page->_count));
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| 	set_page_count(page, 1);
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| }
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| 
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| static inline void __put_page(struct page *page)
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| {
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| 	atomic_dec(&page->_count);
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| }
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| 
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| extern void fastcall __init __free_pages_bootmem(struct page *page,
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| 						unsigned int order);
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| 
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| #endif
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