jfs: add cond_resched() to jfs_lazycommit

The lazy commit thread may run too long without yielding the cpu, if
there is a lot of work to do and it doesn't need to read from disk.

Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>

diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
index f26e4d0..a78409a 100644
--- a/fs/jfs/jfs_txnmgr.c
+++ b/fs/jfs/jfs_txnmgr.c
@@ -2781,6 +2781,7 @@ int jfs_lazycommit(void *arg)
 
 				LAZY_UNLOCK(flags);
 				txLazyCommit(tblk);
+				cond_resched();
 				LAZY_LOCK(flags);
 
 				sbi->commit_state &= ~IN_LAZYCOMMIT;