From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754377Ab0JAHoB (ORCPT ); Fri, 1 Oct 2010 03:44:01 -0400 Received: from f0.cmpxchg.org ([85.214.51.133]:52390 "EHLO cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753373Ab0JAHoA (ORCPT ); Fri, 1 Oct 2010 03:44:00 -0400 Date: Fri, 1 Oct 2010 09:43:54 +0200 From: Johannes Weiner To: xfs@oss.sgi.com Cc: John Hawley , linux-kernel@vger.kernel.org, stable@kernel.org Subject: [patch] xfs: properly account for reclaimed inodes Message-ID: <20101001074354.GF2618@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When marking an inode reclaimable, a per-AG counter is increased, the inode is tagged reclaimable in its per-AG tree, and, when this is the first reclaimable inode in the AG, the AG entry in the per-mount tree is also tagged. When an inode is finally reclaimed, however, it is only deleted from the per-AG tree. Neither the counter is decreased, nor is the parent tree's AG entry untagged properly. Since the tags in the per-mount tree are not cleared, the inode shrinker iterates over all AGs that have had reclaimable inodes at one point in time. The counters on the other hand signal an increasing amount of slab objects to reclaim. Since "70e60ce xfs: convert inode shrinker to per-filesystem context" this is not a real issue anymore because the shrinker bails out after one iteration. But the problem was observable on a machine running v2.6.34, where the reclaimable work increased and each process going into direct reclaim eventually got stuck on the xfs inode shrinking path, trying to scan several million objects. Fix this by properly unwinding the reclaimable-state tracking of an inode when it is reclaimed. Signed-off-by: Johannes Weiner Cc: stable@kernel.org --- fs/xfs/linux-2.6/xfs_sync.c | 19 ++++++++++++++----- 1 files changed, 14 insertions(+), 5 deletions(-) diff --git a/fs/xfs/linux-2.6/xfs_sync.c b/fs/xfs/linux-2.6/xfs_sync.c index d59c4a6..81976ff 100644 --- a/fs/xfs/linux-2.6/xfs_sync.c +++ b/fs/xfs/linux-2.6/xfs_sync.c @@ -668,14 +668,11 @@ xfs_inode_set_reclaim_tag( xfs_perag_put(pag); } -void -__xfs_inode_clear_reclaim_tag( - xfs_mount_t *mp, +STATIC void +__xfs_inode_clear_reclaim( xfs_perag_t *pag, xfs_inode_t *ip) { - radix_tree_tag_clear(&pag->pag_ici_root, - XFS_INO_TO_AGINO(mp, ip->i_ino), XFS_ICI_RECLAIM_TAG); pag->pag_ici_reclaimable--; if (!pag->pag_ici_reclaimable) { /* clear the reclaim tag from the perag radix tree */ @@ -689,6 +686,17 @@ __xfs_inode_clear_reclaim_tag( } } +void +__xfs_inode_clear_reclaim_tag( + xfs_mount_t *mp, + xfs_perag_t *pag, + xfs_inode_t *ip) +{ + radix_tree_tag_clear(&pag->pag_ici_root, + XFS_INO_TO_AGINO(mp, ip->i_ino), XFS_ICI_RECLAIM_TAG); + __xfs_inode_clear_reclaim(pag, ip); +} + /* * Inodes in different states need to be treated differently, and the return * value of xfs_iflush is not sufficient to get this right. The following table @@ -838,6 +846,7 @@ reclaim: if (!radix_tree_delete(&pag->pag_ici_root, XFS_INO_TO_AGINO(ip->i_mount, ip->i_ino))) ASSERT(0); + __xfs_inode_clear_reclaim(pag, ip); write_unlock(&pag->pag_ici_lock); /* -- 1.7.2.3