Re: [PATCH v4][next] xfs: Replace one-element arrays with flexible-array members

[Chen, Rong A]

On 4/14/2021 12:53 AM, Christoph Hellwig wrote:
> On Mon, Apr 12, 2021 at 08:48:08AM -0700, Darrick J. Wong wrote:
> > A couple of revisions ago I specifically asked Gustavo to create these
> > 'silly' sizeof helpers to clean up...
> >
> > > > -					(sizeof(struct xfs_efd_log_item) +
> > > > -					(XFS_EFD_MAX_FAST_EXTENTS - 1) *
> > > > -					sizeof(struct xfs_extent)),
> > > > -					0, 0, NULL);
> > > > +					 struct_size((struct xfs_efd_log_item *)0,
> > > > +					 efd_format.efd_extents,
> > > > +					 XFS_EFD_MAX_FAST_EXTENTS),
> >
> > ...these even uglier multiline statements.  I was also going to ask for
> > these kmem cache users to get cleaned up.  I'd much rather look at:
> >
> > 	xfs_efi_zone = kmem_cache_create("xfs_efi_item",
> > 				sizeof_xfs_efi(XFS_EFI_MAX_FAST_EXTENTS), 0);
> > 	if (!xfs_efi_zone)
> > 		goto the_drop_zone;
> >
> > even if it means another static inline.
>
> Which doesn't really work with struct_size or rather leads to a mess
> like the above as struct_size really wants a variable and not just a
> type.  Making it really nasty for both allocations and creating slab
> caches.  I tried to find a workaround for that, but that makes the
> compiler unhappy based its inlining heuristics.
>
> Anyway, a lot of the helpers are pretty silly as they duplicate stuff
> without cleaning up the underlying mess.  I tried to sort much of this
> out here, still WIP:
>
> http://git.infradead.org/users/hch/xfs.git/shortlog/refs/heads/xfs-array-size

Hi xfs maintainers,

Kindly ping, is there any new progress on this patch series?

Best Regards,
Rong Chen