On Thu, Oct 06, 2016 at 12:44:39PM -0400, Brian Foster wrote:
> On Thu, Sep 29, 2016 at 08:09:52PM -0700, Darrick J. Wong wrote:
> > When destroying the inode, cancel all pending reservations in the CoW
> > fork so that all the reserved blocks go back to the free pile. In
> > theory this sort of cleanup is only needed to clean up after write
> > errors.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> > ---
> > fs/xfs/xfs_super.c | 8 ++++++++
> > 1 file changed, 8 insertions(+)
> >
> >
> > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> > index 204b794..26b45b3 100644
> > --- a/fs/xfs/xfs_super.c
> > +++ b/fs/xfs/xfs_super.c
> > @@ -49,6 +49,7 @@
> > #include "xfs_rmap_item.h"
> > #include "xfs_refcount_item.h"
> > #include "xfs_bmap_item.h"
> > +#include "xfs_reflink.h"
> >
> > #include <linux/namei.h>
> > #include <linux/init.h>
> > @@ -938,6 +939,7 @@ xfs_fs_destroy_inode(
> > struct inode *inode)
> > {
> > struct xfs_inode *ip = XFS_I(inode);
> > + int error;
> >
> > trace_xfs_destroy_inode(ip);
> >
> > @@ -945,6 +947,12 @@ xfs_fs_destroy_inode(
> > XFS_STATS_INC(ip->i_mount, vn_rele);
> > XFS_STATS_INC(ip->i_mount, vn_remove);
> >
> > + error = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF);
> > + if (error && !XFS_FORCED_SHUTDOWN(ip->i_mount))
> > + xfs_warn(ip->i_mount, "Error %d while evicting CoW blocks "
> > + "for inode %llu.",
> > + error, ip->i_ino);
> > +
>
> We don't actually check the inode reflink flag until down in
> xfs_reflink_cancel_cow_blocks(), after we've allocated a transaction.
> That seems potentially heavy weight for reclaim, as if there's a
> performance impact (which I haven't tested) it would affect all
> filesystems afaict (i.e., regardless of whether reflink is supported).
>
> Further, if this isn't a reflink inode, it looks like we actually commit
> the transaction rather than cancel it as well.
Eeek. xfs_reflink_cancel_cow_range (or something) should jump out if
it's not a reflink inode.
--D
>
> Brian
>
> > xfs_inactive(ip);
> >
> > ASSERT(XFS_FORCED_SHUTDOWN(ip->i_mount) || ip->i_delayed_blks == 0);
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
> > the body of a message to majordomo@xxxxxxxxxxxxxxx
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-xfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
