cregit-Linux how code gets into the kernel

Release 4.7 include/linux/quicklist.h

Directory: include/linux
#ifndef LINUX_QUICKLIST_H

#define LINUX_QUICKLIST_H
/*
 * Fast allocations and disposal of pages. Pages must be in the condition
 * as needed after allocation when they are freed. Per cpu lists of pages
 * are kept that only contain node local pages.
 *
 * (C) 2007, SGI. Christoph Lameter <cl@linux.com>
 */
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/percpu.h>

#ifdef CONFIG_QUICKLIST


struct quicklist {
	
void *page;
	
int nr_pages;
};

DECLARE_PER_CPU(struct quicklist, quicklist)[CONFIG_NR_QUICK];

/*
 * The two key functions quicklist_alloc and quicklist_free are inline so
 * that they may be custom compiled for the platform.
 * Specifying a NULL ctor can remove constructor support. Specifying
 * a constant quicklist allows the determination of the exact address
 * in the per cpu area.
 *
 * The fast patch in quicklist_alloc touched only a per cpu cacheline and
 * the first cacheline of the page itself. There is minmal overhead involved.
 */

static inline void *quicklist_alloc(int nr, gfp_t flags, void (*ctor)(void *)) { struct quicklist *q; void **p = NULL; q =&get_cpu_var(quicklist)[nr]; p = q->page; if (likely(p)) { q->page = p[0]; p[0] = NULL; q->nr_pages--; } put_cpu_var(quicklist); if (likely(p)) return p; p = (void *)__get_free_page(flags | __GFP_ZERO); if (ctor && p) ctor(p); return p; }

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christoph lameterchristoph lameter125100.00%1100.00%
Total125100.00%1100.00%


static inline void __quicklist_free(int nr, void (*dtor)(void *), void *p, struct page *page) { struct quicklist *q; q = &get_cpu_var(quicklist)[nr]; *(void **)p = q->page; q->page = p; q->nr_pages++; put_cpu_var(quicklist); }

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PersonTokensPropCommitsCommitProp
christoph lameterchristoph lameter73100.00%1100.00%
Total73100.00%1100.00%


static inline void quicklist_free(int nr, void (*dtor)(void *), void *pp) { __quicklist_free(nr, dtor, pp, virt_to_page(pp)); }

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PersonTokensPropCommitsCommitProp
christoph lameterchristoph lameter38100.00%1100.00%
Total38100.00%1100.00%


static inline void quicklist_free_page(int nr, void (*dtor)(void *), struct page *page) { __quicklist_free(nr, dtor, page_address(page), page); }

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PersonTokensPropCommitsCommitProp
christoph lameterchristoph lameter39100.00%1100.00%
Total39100.00%1100.00%

void quicklist_trim(int nr, void (*dtor)(void *), unsigned long min_pages, unsigned long max_free); unsigned long quicklist_total_size(void); #else
static inline unsigned long quicklist_total_size(void) { return 0; }

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kosaki motohirokosaki motohiro13100.00%1100.00%
Total13100.00%1100.00%

#endif #endif /* LINUX_QUICKLIST_H */

Overall Contributors

PersonTokensPropCommitsCommitProp
christoph lameterchristoph lameter35595.95%266.67%
kosaki motohirokosaki motohiro154.05%133.33%
Total370100.00%3100.00%
Directory: include/linux
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