From 7f7bebefba152c5bdfe961cd2e97e8695a32998c Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Mon, 8 Oct 2012 21:56:01 +1100 Subject: [PATCH] xfs: don't run the sync work if the filesystem is read-only If the filesystem is mounted or remounted read-only, stop the sync worker that tries to flush or cover the log if the filesystem is dirty. It's read-only, so it isn't dirty. Restart it on a remount,rw as necessary. This avoids the need for RO checks in the work. Similarly, stop the sync work when the filesystem is frozen, and start it again when the filesysetm is thawed. This avoids the need for special freeze checks in the work. Signed-off-by: Dave Chinner Reviewed-by: Mark Tinguely Reviewed-by: Christoph Hellwig Signed-off-by: Ben Myers --- fs/xfs/xfs_super.c | 2 ++ fs/xfs/xfs_sync.c | 29 ++++++++++++++++------------- 2 files changed, 18 insertions(+), 13 deletions(-) diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 9805cac81fc9..20fa955d80d1 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1200,6 +1200,7 @@ xfs_fs_remount( * value if it is non-zero, otherwise go with the default. */ xfs_restore_resvblks(mp); + xfs_syncd_queue_sync(mp); } /* rw -> ro */ @@ -1245,6 +1246,7 @@ xfs_fs_unfreeze( struct xfs_mount *mp = XFS_M(sb); xfs_restore_resvblks(mp); + xfs_syncd_queue_sync(mp); return 0; } diff --git a/fs/xfs/xfs_sync.c b/fs/xfs/xfs_sync.c index a68761696ab5..e898d1807044 100644 --- a/fs/xfs/xfs_sync.c +++ b/fs/xfs/xfs_sync.c @@ -323,6 +323,9 @@ xfs_quiesce_data( * Second stage of a quiesce. The data is already synced, now we have to take * care of the metadata. New transactions are already blocked, so we need to * wait for any remaining transactions to drain out before proceeding. + * + * Note: this stops background sync work - the callers must ensure it is started + * again when appropriate. */ void xfs_quiesce_attr( @@ -341,6 +344,9 @@ xfs_quiesce_attr( /* flush all pending changes from the AIL */ xfs_ail_push_all_sync(mp->m_ail); + /* stop background sync work */ + cancel_delayed_work_sync(&mp->m_sync_work); + /* * Just warn here till VFS can correctly support * read-only remount without racing. @@ -379,9 +385,8 @@ xfs_syncd_queue_sync( } /* - * Every sync period we need to unpin all items in the AIL and push them to - * disk. If there is nothing dirty, then we might need to cover the log to - * indicate that the filesystem is idle and not frozen. + * Every sync period we need to push dirty metadata and try to cover the log + * to indicate the filesystem is idle and not frozen. */ void xfs_sync_worker( @@ -391,17 +396,15 @@ xfs_sync_worker( struct xfs_mount, m_sync_work); int error; - if (!(mp->m_flags & XFS_MOUNT_RDONLY)) { - /* dgc: errors ignored here */ - if (mp->m_super->s_writers.frozen == SB_UNFROZEN && - xfs_log_need_covered(mp)) - error = xfs_fs_log_dummy(mp); - else - xfs_log_force(mp, 0); + /* dgc: errors ignored here */ + if (mp->m_super->s_writers.frozen == SB_UNFROZEN && + xfs_log_need_covered(mp)) + error = xfs_fs_log_dummy(mp); + else + xfs_log_force(mp, 0); - /* start pushing all the metadata that is currently dirty */ - xfs_ail_push_all(mp->m_ail); - } + /* start pushing all the metadata that is currently dirty */ + xfs_ail_push_all(mp->m_ail); /* queue us up again */ xfs_syncd_queue_sync(mp);