page-writeback.c: subtract min_free_kbytes from dirtyable memory

When calculating amount of dirtyable memory, min_free_kbytes should be
subtracted because it is not intended for dirty pages.

Addresses http://bugs.debian.org/695182

[akpm@linux-foundation.org: fix up min_free_kbytes extern declarations]
[akpm@linux-foundation.org: fix min() warning]
Signed-off-by: Paul Szabo <psz@maths.usyd.edu.au>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Paul Szabo 2013-02-22 16:34:42 -08:00 committed by Linus Torvalds
parent 08b52706d5
commit 75f7ad8e04
4 changed files with 6 additions and 2 deletions

View File

@ -1393,6 +1393,9 @@ extern void setup_per_cpu_pageset(void);
extern void zone_pcp_update(struct zone *zone);
extern void zone_pcp_reset(struct zone *zone);
/* page_alloc.c */
extern int min_free_kbytes;
/* nommu.c */
extern atomic_long_t mmap_pages_allocated;
extern int nommu_shrink_inode_mappings(struct inode *, size_t, size_t);

View File

@ -105,7 +105,6 @@ extern char core_pattern[];
extern unsigned int core_pipe_limit;
#endif
extern int pid_max;
extern int min_free_kbytes;
extern int pid_max_min, pid_max_max;
extern int sysctl_drop_caches;
extern int percpu_pagelist_fraction;

View File

@ -105,7 +105,6 @@ static int set_recommended_min_free_kbytes(void)
struct zone *zone;
int nr_zones = 0;
unsigned long recommended_min;
extern int min_free_kbytes;
if (!khugepaged_enabled())
return 0;

View File

@ -241,6 +241,9 @@ static unsigned long global_dirtyable_memory(void)
if (!vm_highmem_is_dirtyable)
x -= highmem_dirtyable_memory(x);
/* Subtract min_free_kbytes */
x -= min_t(unsigned long, x, min_free_kbytes >> (PAGE_SHIFT - 10));
return x + 1; /* Ensure that we never return 0 */
}