Re: [PATCH] JBD2: round commit timer up to avoid uncommitted transaction

[Andreas Dilger <adilger@sun.com>]

On Jul 30, 2009  19:47 +0200, Jan Kara wrote:
> > jbd and jbd2 fixes: fix jiffie rounding in jbd commit timer setup code.
> > Rounding down could cause the timer to be fired before the corresponding
> > transaction has expired.  That transaction can stay not committed forever if
> > no new transaction is created or expicit sync/umount happens.
> > 
> > Signed-off-by: Alex Zhuravlev (Tomas) <alex.zhuravlev@sun.com>
> > Signed-off-by: Andreas Dilger <adilger@sun.com>
>
>   Looks fine. You can add:
> Acked-by: Jan Kara <jack@suse.cz>
>   How about a similar JBD fix?

Index: linux-2.6.27.21-0.1/fs/jbd/transaction.c
===================================================================
--- linux-2.6.27.21-0.1.orig/fs/jbd/transaction.c	2009-06-10 11:11:41.000000000 -0600
+++ linux-2.6.27.21-0.1/fs/jbd/transaction.c	2009-06-10 11:12:32.000000000 -0600
@@ -54,7 +54,7 @@
 	spin_lock_init(&transaction->t_inode_list);
 
 	/* Set up the commit timer for the new transaction. */
-	journal->j_commit_timer.expires = round_jiffies(transaction->t_expires);
+	journal->j_commit_timer.expires = round_jiffies_up(transaction->t_expires);
 	add_timer(&journal->j_commit_timer);
 
 	J_ASSERT(journal->j_running_transaction == NULL);

Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.