On Mon, Nov 19, 2018 at 09:07:27PM -0800, Hugh Dickins wrote: > I don't much like my original use of the name "swap_index", when it was > not the index in a swapfile (though it was the index in the radix tree); > but it will become a correct name with your patch. > > Though Matthew Wilcox seems to want us to avoid saying "radix tree"... Naming is hard ... but the Linux radix tree looks almost nothing like a classic computer science radix tree. If you try to reconcile our implementation with the wikipedia article on radix trees, you'll get very confused. A lot of places where we were saying 'radix tree' in comments should really have said 'page cache'. So is this a swap cache index? I'm not really familiar enough with the swapping code to say.