Re: [patch v4 06/13] [PATCH 06/13] xfs: xfs_sync_data is redundant.

Ben Myers
2012-10-05T18:03:22Z

Hey Mark,

On Fri, Oct 05, 2012 at 12:55:45PM -0500, Mark Tinguely wrote:
> On 10/05/12 12:18, Ben Myers wrote:
> >Index: xfs/fs/xfs/xfs_mount.h
> >===================================================================
> >--- xfs.orig/fs/xfs/xfs_mount.h
> >+++ xfs/fs/xfs/xfs_mount.h
> >@@ -198,7 +198,6 @@ typedef struct xfs_mount {
> > #endif
> > struct xfs_mru_cache *m_filestream; /* per-mount filestream data */
> > struct delayed_work m_reclaim_work; /* background inode reclaim */
> >- struct work_struct m_flush_work; /* background inode flush */
> > __int64_t m_update_flags; /* sb flags we need to update
> > on the next remount,rw */
> > struct shrinker m_inode_shrink; /* inode reclaim shrinker */
> >@@ -381,6 +380,27 @@ extern int xfs_dev_is_read_only(struct x
> >
> > extern void xfs_set_low_space_thresholds(struct xfs_mount *);
> >
> >+/*
> >+ * Flush all dirty data to disk. Must not be called while holding an XFS_ILOCK
> >+ * or a page lock.
> >+ *
> >+ * We have to hold the s_umount lock here, but because this call can nest
> >+ * inside i_mutex (the parent directory in the create case, held by the VFS),
> >+ * we have to use down_read_trylock() to avoid potential deadlocks. In
> >+ * practice, this trylock will succeed on almost every attempt as
> >+ * unmount/remount type operations are exceedingly rare.
> >+ */
> >+static inline void
> >+xfs_flush_inodes(struct xfs_mount *mp)
> >+{
> >+ struct super_block *sb = mp->m_super;
> >+
> >+ if (down_read_trylock(&sb->s_umount)) {
> >+ sync_inodes_sb(sb);
> >+ up_read(&sb->s_umount);
> >+ }
> >+}
> >+
>
>
> Was this suppose to be in xfs_inode.h? Otherwise....

Christoph suggested that xfs_flush_inodes should take an xfs_mount instead of
an inode. It is operating on the super_block level to flush multiple inodes
rather than the single inode whose pointer was passed in, so I moved it from
xfs_inode.h to xfs_mount.h.

Regards,
Ben