forked from mirrors/linux
		
	There are various email addresses for me throughout the kernel. Use the one that will always be valid. Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			93 lines
		
	
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			93 lines
		
	
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef LINUX_QUICKLIST_H
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#define LINUX_QUICKLIST_H
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/*
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 * Fast allocations and disposal of pages. Pages must be in the condition
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 * as needed after allocation when they are freed. Per cpu lists of pages
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 * are kept that only contain node local pages.
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 *
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 * (C) 2007, SGI. Christoph Lameter <cl@linux.com>
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 */
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#include <linux/kernel.h>
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#include <linux/gfp.h>
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#include <linux/percpu.h>
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#ifdef CONFIG_QUICKLIST
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struct quicklist {
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	void *page;
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	int nr_pages;
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};
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DECLARE_PER_CPU(struct quicklist, quicklist)[CONFIG_NR_QUICK];
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/*
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 * The two key functions quicklist_alloc and quicklist_free are inline so
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 * that they may be custom compiled for the platform.
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 * Specifying a NULL ctor can remove constructor support. Specifying
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 * a constant quicklist allows the determination of the exact address
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 * in the per cpu area.
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 *
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 * The fast patch in quicklist_alloc touched only a per cpu cacheline and
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 * the first cacheline of the page itself. There is minmal overhead involved.
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 */
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static inline void *quicklist_alloc(int nr, gfp_t flags, void (*ctor)(void *))
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{
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	struct quicklist *q;
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	void **p = NULL;
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	q =&get_cpu_var(quicklist)[nr];
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	p = q->page;
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	if (likely(p)) {
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		q->page = p[0];
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		p[0] = NULL;
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		q->nr_pages--;
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	}
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	put_cpu_var(quicklist);
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	if (likely(p))
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		return p;
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	p = (void *)__get_free_page(flags | __GFP_ZERO);
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	if (ctor && p)
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		ctor(p);
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	return p;
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}
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static inline void __quicklist_free(int nr, void (*dtor)(void *), void *p,
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	struct page *page)
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{
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	struct quicklist *q;
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	q = &get_cpu_var(quicklist)[nr];
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	*(void **)p = q->page;
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	q->page = p;
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	q->nr_pages++;
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	put_cpu_var(quicklist);
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}
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static inline void quicklist_free(int nr, void (*dtor)(void *), void *pp)
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{
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	__quicklist_free(nr, dtor, pp, virt_to_page(pp));
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}
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static inline void quicklist_free_page(int nr, void (*dtor)(void *),
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							struct page *page)
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{
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	__quicklist_free(nr, dtor, page_address(page), page);
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}
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void quicklist_trim(int nr, void (*dtor)(void *),
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	unsigned long min_pages, unsigned long max_free);
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unsigned long quicklist_total_size(void);
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#else
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static inline unsigned long quicklist_total_size(void)
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{
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	return 0;
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}
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#endif
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#endif /* LINUX_QUICKLIST_H */
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