/* SPDX-License-Identifier: GPL-2.0 */
|
#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;
|
}
|
|
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);
|
}
|
|
static inline void quicklist_free(int nr, void (*dtor)(void *), void *pp)
|
{
|
__quicklist_free(nr, dtor, pp, virt_to_page(pp));
|
}
|
|
static inline void quicklist_free_page(int nr, void (*dtor)(void *),
|
struct page *page)
|
{
|
__quicklist_free(nr, dtor, page_address(page), page);
|
}
|
|
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;
|
}
|
|
#endif
|
|
#endif /* LINUX_QUICKLIST_H */
|
