[PATCH] swsusp: make image size limit tunable
Make the suspend image size limit tunable via /sys/power/image_size.
It is necessary for systems on which there is a limited amount of swap
available for suspend. It can also be useful for optimizing performance of
swsusp on systems with 1 GB of RAM or more.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index 6d5ceaf..d760a6a 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -69,6 +69,14 @@
#include "power.h"
+/*
+ * Preferred image size in MB (tunable via /sys/power/image_size).
+ * When it is set to N, swsusp will do its best to ensure the image
+ * size will not exceed N MB, but if that is impossible, it will
+ * try to create the smallest image possible.
+ */
+unsigned int image_size = 500;
+
#ifdef CONFIG_HIGHMEM
unsigned int count_highmem_pages(void);
int save_highmem(void);
@@ -647,7 +655,7 @@
if (!tmp)
return -ENOMEM;
pages += tmp;
- } else if (size > (IMAGE_SIZE * 1024 * 1024) / PAGE_SIZE) {
+ } else if (size > (image_size * 1024 * 1024) / PAGE_SIZE) {
tmp = shrink_all_memory(SHRINK_BITE);
pages += tmp;
}