mirror of
https://github.com/torvalds/linux.git
synced 2025-11-04 10:40:15 +02:00
93e205a728
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>
102 lines
2.4 KiB
C
102 lines
2.4 KiB
C
/*
|
|
* Quicklist support.
|
|
*
|
|
* Quicklists are light weight lists of pages that have a defined state
|
|
* on alloc and free. Pages must be in the quicklist specific defined state
|
|
* (zero by default) when the page is freed. It seems that the initial idea
|
|
* for such lists first came from Dave Miller and then various other people
|
|
* improved on it.
|
|
*
|
|
* Copyright (C) 2007 SGI,
|
|
* Christoph Lameter <cl@linux.com>
|
|
* Generalized, added support for multiple lists and
|
|
* constructors / destructors.
|
|
*/
|
|
#include <linux/kernel.h>
|
|
|
|
#include <linux/gfp.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/mmzone.h>
|
|
#include <linux/quicklist.h>
|
|
|
|
DEFINE_PER_CPU(struct quicklist [CONFIG_NR_QUICK], quicklist);
|
|
|
|
#define FRACTION_OF_NODE_MEM 16
|
|
|
|
static unsigned long max_pages(unsigned long min_pages)
|
|
{
|
|
unsigned long node_free_pages, max;
|
|
int node = numa_node_id();
|
|
struct zone *zones = NODE_DATA(node)->node_zones;
|
|
int num_cpus_on_node;
|
|
|
|
node_free_pages =
|
|
#ifdef CONFIG_ZONE_DMA
|
|
zone_page_state(&zones[ZONE_DMA], NR_FREE_PAGES) +
|
|
#endif
|
|
#ifdef CONFIG_ZONE_DMA32
|
|
zone_page_state(&zones[ZONE_DMA32], NR_FREE_PAGES) +
|
|
#endif
|
|
zone_page_state(&zones[ZONE_NORMAL], NR_FREE_PAGES);
|
|
|
|
max = node_free_pages / FRACTION_OF_NODE_MEM;
|
|
|
|
num_cpus_on_node = cpumask_weight(cpumask_of_node(node));
|
|
max /= num_cpus_on_node;
|
|
|
|
return max(max, min_pages);
|
|
}
|
|
|
|
static long min_pages_to_free(struct quicklist *q,
|
|
unsigned long min_pages, long max_free)
|
|
{
|
|
long pages_to_free;
|
|
|
|
pages_to_free = q->nr_pages - max_pages(min_pages);
|
|
|
|
return min(pages_to_free, max_free);
|
|
}
|
|
|
|
/*
|
|
* Trim down the number of pages in the quicklist
|
|
*/
|
|
void quicklist_trim(int nr, void (*dtor)(void *),
|
|
unsigned long min_pages, unsigned long max_free)
|
|
{
|
|
long pages_to_free;
|
|
struct quicklist *q;
|
|
|
|
q = &get_cpu_var(quicklist)[nr];
|
|
if (q->nr_pages > min_pages) {
|
|
pages_to_free = min_pages_to_free(q, min_pages, max_free);
|
|
|
|
while (pages_to_free > 0) {
|
|
/*
|
|
* We pass a gfp_t of 0 to quicklist_alloc here
|
|
* because we will never call into the page allocator.
|
|
*/
|
|
void *p = quicklist_alloc(nr, 0, NULL);
|
|
|
|
if (dtor)
|
|
dtor(p);
|
|
free_page((unsigned long)p);
|
|
pages_to_free--;
|
|
}
|
|
}
|
|
put_cpu_var(quicklist);
|
|
}
|
|
|
|
unsigned long quicklist_total_size(void)
|
|
{
|
|
unsigned long count = 0;
|
|
int cpu;
|
|
struct quicklist *ql, *q;
|
|
|
|
for_each_online_cpu(cpu) {
|
|
ql = per_cpu(quicklist, cpu);
|
|
for (q = ql; q < ql + CONFIG_NR_QUICK; q++)
|
|
count += q->nr_pages;
|
|
}
|
|
return count;
|
|
}
|
|
|