Check for pages with errors within shrink_page_list() and if found, try
to unuse them which will trigger the functions to mark the page bad. The
page will then be allocated a new swap page.
If a swap page write error occurs, don't disable page reclaim.
These patches are a based on a patch by Nick Piggin and some of my own
patches/bugfixes as discussed on LKML.
Signed-off-by: Richard Purdie <[email protected]>
---
mm/page_io.c | 3 ---
mm/vmscan.c | 9 +++++++++
2 files changed, 9 insertions(+), 3 deletions(-)
Index: git/mm/page_io.c
===================================================================
--- git.orig/mm/page_io.c 2007-01-07 21:39:29.000000000 +0000
+++ git/mm/page_io.c 2007-01-08 11:40:38.000000000 +0000
@@ -59,15 +59,12 @@ static int end_swap_bio_write(struct bio
* Re-dirty the page in order to avoid it being reclaimed.
* Also print a dire warning that things will go BAD (tm)
* very quickly.
- *
- * 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",
imajor(bio->bi_bdev->bd_inode),
iminor(bio->bi_bdev->bd_inode),
(unsigned long long)bio->bi_sector);
- ClearPageReclaim(page);
}
end_page_writeback(page);
bio_put(bio);
Index: git/mm/vmscan.c
===================================================================
--- git.orig/mm/vmscan.c 2007-01-07 21:39:29.000000000 +0000
+++ git/mm/vmscan.c 2007-01-08 11:40:00.000000000 +0000
@@ -490,6 +490,15 @@ static unsigned long shrink_page_list(st
#ifdef CONFIG_SWAP
/*
+ * Encountered an error last time? Try to remove the
+ * page from its current position, which will notice
+ * the error and mark that swap entry bad. Then we can
+ * try allocating another swap entry.
+ */
+ if (PageSwapCache(page) && unlikely(PageError(page)))
+ try_to_unuse_page_entry(page);
+
+ /*
* Anonymous process memory has backing store?
* Try to allocate it some swap space here.
*/