From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 3a.49.1343.static.theplanet.com ([67.19.73.58] helo=pug.o-hand.com) by canuck.infradead.org with esmtps (Exim 4.63 #1 (Red Hat Linux)) id 1HNA61-0005Mp-3y for linux-mtd@lists.infradead.org; Fri, 02 Mar 2007 10:55:50 -0500 Subject: [PATCH 3/9] swap: Catch pages with errors and mark as bad From: Richard Purdie To: Nick Piggin , Hugh Dickins , kernel list , linux-mtd@lists.infradead.org, dwmw2@infradead.org Content-Type: text/plain Date: Fri, 02 Mar 2007 15:54:38 +0000 Message-Id: <1172850879.11149.122.camel@localhost.localdomain> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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. Based on a patch by Nick Piggin and some of my own changes as discussed on LKML. Signed-off-by: Richard Purdie --- mm/page_io.c | 3 --- mm/vmscan.c | 9 +++++++++ 2 files changed, 9 insertions(+), 3 deletions(-) Index: linux/mm/page_io.c =================================================================== --- linux.orig/mm/page_io.c 2007-02-28 18:12:16.000000000 +0000 +++ linux/mm/page_io.c 2007-02-28 18:12:44.000000000 +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: linux/mm/vmscan.c =================================================================== --- linux.orig/mm/vmscan.c 2007-02-28 18:12:34.000000000 +0000 +++ linux/mm/vmscan.c 2007-02-28 18:12:44.000000000 +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. */