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-rw-r--r--kernel/power/snapshot.c80
1 files changed, 78 insertions, 2 deletions
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 33e2e4a819f..523a451b45d 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -39,6 +39,14 @@ static int swsusp_page_is_free(struct page *);
static void swsusp_set_page_forbidden(struct page *);
static void swsusp_unset_page_forbidden(struct page *);
+/*
+ * Preferred image size in bytes (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 bytes, but if that is impossible, it will
+ * try to create the smallest image possible.
+ */
+unsigned long image_size = 500 * 1024 * 1024;
+
/* List of PBEs needed for restoring the pages that were allocated before
* the suspend and included in the suspend image, but have also been
* allocated by the "resume" kernel, so their contents cannot be written
@@ -840,7 +848,7 @@ static struct page *saveable_highmem_page(struct zone *zone, unsigned long pfn)
* pages.
*/
-unsigned int count_highmem_pages(void)
+static unsigned int count_highmem_pages(void)
{
struct zone *zone;
unsigned int n = 0;
@@ -902,7 +910,7 @@ static struct page *saveable_page(struct zone *zone, unsigned long pfn)
* pages.
*/
-unsigned int count_data_pages(void)
+static unsigned int count_data_pages(void)
{
struct zone *zone;
unsigned long pfn, max_zone_pfn;
@@ -1058,6 +1066,74 @@ void swsusp_free(void)
buffer = NULL;
}
+/**
+ * swsusp_shrink_memory - Try to free as much memory as needed
+ *
+ * ... but do not OOM-kill anyone
+ *
+ * Notice: all userland should be stopped before it is called, or
+ * livelock is possible.
+ */
+
+#define SHRINK_BITE 10000
+static inline unsigned long __shrink_memory(long tmp)
+{
+ if (tmp > SHRINK_BITE)
+ tmp = SHRINK_BITE;
+ return shrink_all_memory(tmp);
+}
+
+int swsusp_shrink_memory(void)
+{
+ long tmp;
+ struct zone *zone;
+ unsigned long pages = 0;
+ unsigned int i = 0;
+ char *p = "-\\|/";
+ struct timeval start, stop;
+
+ printk(KERN_INFO "PM: Shrinking memory... ");
+ do_gettimeofday(&start);
+ do {
+ long size, highmem_size;
+
+ highmem_size = count_highmem_pages();
+ size = count_data_pages() + PAGES_FOR_IO + SPARE_PAGES;
+ tmp = size;
+ size += highmem_size;
+ for_each_populated_zone(zone) {
+ tmp += snapshot_additional_pages(zone);
+ if (is_highmem(zone)) {
+ highmem_size -=
+ zone_page_state(zone, NR_FREE_PAGES);
+ } else {
+ tmp -= zone_page_state(zone, NR_FREE_PAGES);
+ tmp += zone->lowmem_reserve[ZONE_NORMAL];
+ }
+ }
+
+ if (highmem_size < 0)
+ highmem_size = 0;
+
+ tmp += highmem_size;
+ if (tmp > 0) {
+ tmp = __shrink_memory(tmp);
+ if (!tmp)
+ return -ENOMEM;
+ pages += tmp;
+ } else if (size > image_size / PAGE_SIZE) {
+ tmp = __shrink_memory(size - (image_size / PAGE_SIZE));
+ pages += tmp;
+ }
+ printk("\b%c", p[i++%4]);
+ } while (tmp > 0);
+ do_gettimeofday(&stop);
+ printk("\bdone (%lu pages freed)\n", pages);
+ swsusp_show_speed(&start, &stop, pages, "Freed");
+
+ return 0;
+}
+
#ifdef CONFIG_HIGHMEM
/**
* count_pages_for_highmem - compute the number of non-highmem pages