Re: [PATCH v6 05/24] erofs: add inode operations

[Christoph Hellwig]

On Thu, Aug 29, 2019 at 07:59:22PM +0800, Gao Xiang wrote:
> On Thu, Aug 29, 2019 at 03:24:26AM -0700, Christoph Hellwig wrote:
> 
> []
> 
> > 
> > > +
> > > +		/* fill last page if inline data is available */
> > > +		err = fill_inline_data(inode, data, ofs);
> > 
> > Well, I think you should move the is_inode_flat_inline and
> > (S_ISLNK(inode->i_mode) && inode->i_size < PAGE_SIZE) checks from that
> > helper here, as otherwise you make everyone wonder why you'd always
> > fill out the inline data.
> 
> Currently, fill_inline_data() only fills for fast symlink,
> later we can fill any tail-end block (such as dir block)
> for our requirements.

So change it when that later changes actually come in.  And even then
having the checks outside the function is a lot more obvious.

> And I think that is minor.

The problem is that each of these issues might appear minor on their
own.  But combined a lot of the coding style choices lead to code that
is more suitable an obsfucated code contest than the Linux kernel as
trying to understand even just a few places requires jumping through
tons of helpers with misleading names and spread over various files.

> The consideration is simply because iget_locked performs better
> than iget5_locked.

In what benchmark do the differences show up?