From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Sandeen Subject: Re: [PATCH] ext3: Don't warn from writepage when readonly inode is spotted after error Date: Thu, 22 Dec 2011 10:11:36 -0600 Message-ID: <4EF356B8.5010605@redhat.com> References: <1324569415-9824-1-git-send-email-jack@suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: linux-ext4@vger.kernel.org To: Jan Kara Return-path: Received: from mx1.redhat.com ([209.132.183.28]:6231 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753139Ab1LVQMD (ORCPT ); Thu, 22 Dec 2011 11:12:03 -0500 In-Reply-To: <1324569415-9824-1-git-send-email-jack@suse.cz> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 12/22/11 9:56 AM, Jan Kara wrote: > WARN_ON_ONCE(IS_RDONLY(inode)) tends to trip when filesystem hits error and is > remounted read-only. This unnecessarily scares users (well, they should be > scared because of filesystem error, but the stack trace distracts them from the > right source of their fear ;-). We could as well just remove the WARN_ON but > it's not hard to fix it to not trip on filesystem with errors and not use more > cycles in the common case so that's what we do. I've seen that too and it is distracting. Looks good to me, aside from the rather long lines ;) -Eric > Signed-off-by: Jan Kara > --- > fs/ext3/inode.c | 18 +++++++++++++++--- > 1 files changed, 15 insertions(+), 3 deletions(-) > > I carry this patch in my tree and will merge it with Linus in the next merge > window if noone objects. > > diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c > index a8d3217..91ac85b 100644 > --- a/fs/ext3/inode.c > +++ b/fs/ext3/inode.c > @@ -1623,7 +1623,11 @@ static int ext3_ordered_writepage(struct page *page, > int err; > > J_ASSERT(PageLocked(page)); > - WARN_ON_ONCE(IS_RDONLY(inode)); > + /* > + * We don't want to warn for emergency remount. The condition is ordered to avoid > + * dereferencing inode->i_sb in non-error case to avoid slow-downs. > + */ > + WARN_ON_ONCE(IS_RDONLY(inode) && !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ERROR_FS)); > > /* > * We give up here if we're reentered, because it might be for a > @@ -1698,7 +1702,11 @@ static int ext3_writeback_writepage(struct page *page, > int err; > > J_ASSERT(PageLocked(page)); > - WARN_ON_ONCE(IS_RDONLY(inode)); > + /* > + * We don't want to warn for emergency remount. The condition is ordered to avoid > + * dereferencing inode->i_sb in non-error case to avoid slow-downs. > + */ > + WARN_ON_ONCE(IS_RDONLY(inode) && !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ERROR_FS)); > > if (ext3_journal_current_handle()) > goto out_fail; > @@ -1741,7 +1749,11 @@ static int ext3_journalled_writepage(struct page *page, > int err; > > J_ASSERT(PageLocked(page)); > - WARN_ON_ONCE(IS_RDONLY(inode)); > + /* > + * We don't want to warn for emergency remount. The condition is ordered to avoid > + * dereferencing inode->i_sb in non-error case to avoid slow-downs. > + */ > + WARN_ON_ONCE(IS_RDONLY(inode) && !(EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ERROR_FS)); > > if (ext3_journal_current_handle()) > goto no_write;