[PATCH] remove static variable mm/page-writeback.c:total_pages

page-writeback.c has a static local variable "total_pages", which is the
total number of pages in the system.

There is a global variable "vm_total_pages", which is the total number of
pages the VM controls.

Both are assigned from the return value of nr_free_pagecache_pages().

This patch removes the local variable and uses the global variable in that
place.

One more issue with the local static variable "total_pages" is that it is
not updated when new pages are hot-added.  Since vm_total_pages is updated
when new pages are hot-added, this patch fixes that problem too.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Chandra Seetharaman 2006-09-29 02:01:24 -07:00 committed by Linus Torvalds
parent 153dcc54df
commit 40c99aae23

View File

@ -46,7 +46,6 @@
*/
static long ratelimit_pages = 32;
static long total_pages; /* The total number of pages in the machine. */
static int dirty_exceeded __cacheline_aligned_in_smp; /* Dirty mem may be over limit */
/*
@ -126,7 +125,7 @@ get_dirty_limits(long *pbackground, long *pdirty,
int unmapped_ratio;
long background;
long dirty;
unsigned long available_memory = total_pages;
unsigned long available_memory = vm_total_pages;
struct task_struct *tsk;
#ifdef CONFIG_HIGHMEM
@ -141,7 +140,7 @@ get_dirty_limits(long *pbackground, long *pdirty,
unmapped_ratio = 100 - ((global_page_state(NR_FILE_MAPPED) +
global_page_state(NR_ANON_PAGES)) * 100) /
total_pages;
vm_total_pages;
dirty_ratio = vm_dirty_ratio;
if (dirty_ratio > unmapped_ratio / 2)
@ -504,7 +503,7 @@ void laptop_sync_completion(void)
static void set_ratelimit(void)
{
ratelimit_pages = total_pages / (num_online_cpus() * 32);
ratelimit_pages = vm_total_pages / (num_online_cpus() * 32);
if (ratelimit_pages < 16)
ratelimit_pages = 16;
if (ratelimit_pages * PAGE_CACHE_SIZE > 4096 * 1024)
@ -533,9 +532,7 @@ void __init page_writeback_init(void)
long buffer_pages = nr_free_buffer_pages();
long correction;
total_pages = nr_free_pagecache_pages();
correction = (100 * 4 * buffer_pages) / total_pages;
correction = (100 * 4 * buffer_pages) / vm_total_pages;
if (correction < 100) {
dirty_background_ratio *= correction;