On Thu, Oct 01, 2020 at 01:32:56PM -0400, Brian Foster wrote:
> On Tue, Sep 29, 2020 at 10:43:44AM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> >
> > When xfs_defer_capture extracts the deferred ops and transaction state
> > from a transaction, it should record the transaction reservation type
> > from the old transaction so that when we continue the dfops chain, we
> > still use the same reservation parameters.
> >
> > Doing this means that the log item recovery functions get to determine
> > the transaction reservation instead of abusing tr_itruncate in yet
> > another part of xfs.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> > ---
>
> Much nicer, and FWIW this is pretty much the approach I was wondering
> about wrt to the block reservation in the previous patch..
>
> > fs/xfs/libxfs/xfs_defer.c | 9 +++++++++
> > fs/xfs/libxfs/xfs_defer.h | 1 +
> > fs/xfs/xfs_log_recover.c | 4 ++--
> > 3 files changed, 12 insertions(+), 2 deletions(-)
> >
> >
> > diff --git a/fs/xfs/libxfs/xfs_defer.c b/fs/xfs/libxfs/xfs_defer.c
> > index 0cceebb390c4..4caaf5527403 100644
> > --- a/fs/xfs/libxfs/xfs_defer.c
> > +++ b/fs/xfs/libxfs/xfs_defer.c
> > @@ -579,6 +579,15 @@ xfs_defer_ops_capture(
> > dfc->dfc_blkres = tp->t_blk_res - tp->t_blk_res_used;
> > tp->t_blk_res = tp->t_blk_res_used;
> >
> > + /*
> > + * Preserve the transaction reservation type. The logcount is
> > + * hardwired to 1 to so that we can make forward progress in recovery
> > + * no matter how full the log might be, at a cost of more regrants.
> > + */
> > + dfc->dfc_tres.tr_logres = tp->t_log_res;
> > + dfc->dfc_tres.tr_logcount = 1;
> > + dfc->dfc_tres.tr_logflags = XFS_TRANS_PERM_LOG_RES;
>
> Any real need to allocate these last two fields in every captured chain
> when they're basically hardcoded? If not, it might be a bit more
> efficient to put an xfs_trans_res on the stack in
> xlog_finish_defer_ops() and just save the logres value here.
Ok, will do.
--D
>
> Brian
>
> > +
> > return dfc;
> > }
> >
> > diff --git a/fs/xfs/libxfs/xfs_defer.h b/fs/xfs/libxfs/xfs_defer.h
> > index b1c7b761afd5..c447c79bbe74 100644
> > --- a/fs/xfs/libxfs/xfs_defer.h
> > +++ b/fs/xfs/libxfs/xfs_defer.h
> > @@ -76,6 +76,7 @@ struct xfs_defer_capture {
> > struct list_head dfc_dfops;
> > unsigned int dfc_tpflags;
> > unsigned int dfc_blkres;
> > + struct xfs_trans_res dfc_tres;
> > };
> >
> > /*
> > diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
> > index b06c9881a13d..46e750279634 100644
> > --- a/fs/xfs/xfs_log_recover.c
> > +++ b/fs/xfs/xfs_log_recover.c
> > @@ -2442,8 +2442,8 @@ xlog_finish_defer_ops(
> > int error = 0;
> >
> > list_for_each_entry_safe(dfc, next, capture_list, dfc_list) {
> > - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0,
> > - 0, XFS_TRANS_RESERVE, &tp);
> > + error = xfs_trans_alloc(mp, &dfc->dfc_tres, 0, 0,
> > + XFS_TRANS_RESERVE, &tp);
> > if (error)
> > return error;
> >
> >
>
