swsusp: free more memory

Move the definition of PAGES_FOR_IO to kernel/power/power.h and introduce
SPARE_PAGES representing the number of pages that should be freed by the
swsusp's memory shrinker in addition to PAGES_FOR_IO so that device drivers
can allocate some memory (up to 1 MB total) in their .suspend() routines
without causing the suspend to fail.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: Nigel Cunningham <nigel@nigel.suspend2.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Rafael J. Wysocki 2007-05-06 14:50:52 -07:00 committed by Linus Torvalds
parent 9b95e43763
commit 56f99bcb52
3 changed files with 12 additions and 8 deletions

View file

@ -52,10 +52,4 @@ struct saved_context;
void __save_processor_state(struct saved_context *ctxt);
void __restore_processor_state(struct saved_context *ctxt);
/*
* XXX: We try to keep some more pages free so that I/O operations succeed
* without paging. Might this be more?
*/
#define PAGES_FOR_IO 1024
#endif /* _LINUX_SWSUSP_H */

View file

@ -14,8 +14,18 @@ struct swsusp_info {
#ifdef CONFIG_SOFTWARE_SUSPEND
extern int pm_suspend_disk(void);
/*
* Keep some memory free so that I/O operations can succeed without paging
* [Might this be more than 4 MB?]
*/
#define PAGES_FOR_IO ((4096 * 1024) >> PAGE_SHIFT)
/*
* Keep 1 MB of memory free so that device drivers can allocate some pages in
* their .suspend() routines without breaking the suspend to disk.
*/
#define SPARE_PAGES ((1024 * 1024) >> PAGE_SHIFT)
extern int pm_suspend_disk(void);
#else
static inline int pm_suspend_disk(void)
{

View file

@ -233,7 +233,7 @@ int swsusp_shrink_memory(void)
long size, highmem_size;
highmem_size = count_highmem_pages();
size = count_data_pages() + PAGES_FOR_IO;
size = count_data_pages() + PAGES_FOR_IO + SPARE_PAGES;
tmp = size;
size += highmem_size;
for_each_zone (zone)