mm: swap: Rate limit swap write errors
If an error occurs in the swap subsystem when writing pages
out to a swap device the system might get overflowed with
logging errors because the mm subsystem will continously try
to swap out pages even in the event of error on the swap
device.
Reduce the amount of logging to prevent the kernel log
from being filled with these error messages.
Change-Id: Iddaf6c32ae87132817482cc4cb68b909a1c527e6
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
diff --git a/mm/page_io.c b/mm/page_io.c
index e60e43f..1499e1c 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -20,8 +20,15 @@
#include <linux/swapops.h>
#include <linux/writeback.h>
#include <linux/blkdev.h>
+#include <linux/ratelimit.h>
#include <asm/pgtable.h>
+/*
+ * We don't need to see swap errors more than once every 1 second to know
+ * that a problem is occurring.
+ */
+#define SWAP_ERROR_LOG_RATE_MS 1000
+
static struct bio *get_swap_bio(gfp_t gfp_flags,
struct page *page, bio_end_io_t end_io)
{
@@ -46,6 +53,7 @@
{
const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
struct page *page = bio->bi_io_vec[0].bv_page;
+ static unsigned long swap_error_rs_time;
if (!uptodate) {
SetPageError(page);
@@ -58,7 +66,9 @@
* Also clear PG_reclaim to avoid rotate_reclaimable_page()
*/
set_page_dirty(page);
- printk(KERN_ALERT "Write-error on swap-device (%u:%u:%Lu)\n",
+ if (printk_timed_ratelimit(&swap_error_rs_time,
+ SWAP_ERROR_LOG_RATE_MS))
+ printk(KERN_ALERT "Write-error on swap-device (%u:%u:%Lu)\n",
imajor(bio->bi_bdev->bd_inode),
iminor(bio->bi_bdev->bd_inode),
(unsigned long long)bio->bi_sector);