On Wed, 13 Jul 2011, Andrew Morton wrote:
> On Tue, 12 Jul 2011 15:08:58 -0700 (PDT)
> Hugh Dickins <hughd@google.com> wrote:
> > 
> > I'll keep the bland naming, if that's okay, but send a patch adding
> > a line of comment in such places.  Mentioning shmem, tmpfs, swap.
> 
> A better fix would be to create a nicely-documented filemap-specific
> function with a non-bland name which simply wraps
> radix_tree_exception().

I did yesterday try out page_tree_entry_is_not_a_page() to wrap
radix_tree_exceptional_entry(); but (a) I'm wary of negative names,
(b) it was hard to explain why radix_tree_deref_retry() is not a
part of that case, and (c) does a further wrapper help or obscure?

I've skirted the issue in the patch 3/3 I'm about to send you,
maybe you'll think it an improvement, maybe not: I'm neutral.

Hugh