Re: [PATCH 26/28] xfs: use xfs_ail_push_all in xfs_reclaim_inodes

Dave Chinner
2019-11-14T21:53:54Z

On Wed, Nov 06, 2019 at 12:22:15PM -0500, Brian Foster wrote:
> On Fri, Nov 01, 2019 at 10:46:16AM +1100, Dave Chinner wrote:
> > From: Dave Chinner <dchinner@redhat.com>
> >
> > If we are reclaiming all inodes, it is likely we need to flush the
> > entire AIL to do that. We have mechanisms to do that without needing
> > to push to a specific LSN.
> >
> > Convert xfs_relaim_all_inodes() to use xfs_ail_push_all variant so
> > we can get rid of the hacky xfs_ail_push_sync() scaffolding we used
> > to support the intermediate stages of the non-blocking reclaim
> > changeset.
> >
> > Signed-off-by: Dave Chinner <dchinner@redhat.com>
> > ---
> > fs/xfs/xfs_icache.c | 17 +++++++++++------
> > fs/xfs/xfs_trans_ail.c | 32 --------------------------------
> > fs/xfs/xfs_trans_priv.h | 2 --
> > 3 files changed, 11 insertions(+), 40 deletions(-)
> >
> > diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
> > index 71a729e29260..11bf4768d491 100644
> > --- a/fs/xfs/xfs_icache.c
> > +++ b/fs/xfs/xfs_icache.c
> ...
> > @@ -1066,13 +1074,10 @@ xfs_reclaim_all_inodes(
> > xfs_inode_reclaim_isolate, &ra, to_free);
> > xfs_dispose_inodes(&ra.freeable);
> >
> > - if (freed == 0) {
> > + if (freed == 0)
> > xfs_log_force(mp, XFS_LOG_SYNC);
> > - xfs_ail_push_all(mp->m_ail);
> > - } else if (ra.lowest_lsn != NULLCOMMITLSN) {
> > - xfs_ail_push_sync(mp->m_ail, ra.lowest_lsn);
> > - }
> > - cond_resched();
> > + else if (ra.dirty_skipped)
> > + congestion_wait(BLK_RW_ASYNC, HZ/10);
>
> Why not use xfs_ail_push_all_sync() in this function and skip the direct
> stall? This is only used in the unmount and quiesce paths so the big
> hammer approach seems reasonable.

Ok, that's a good simplification :)

-Dave.
--
Dave Chinner
david@fromorbit.com