On Mon, Aug 30, 2021 at 02:33:05PM +0200, Johan Hovold wrote:
On Mon, Aug 30, 2021 at 01:16:07PM +0100, Matthew Wilcox wrote:
On Mon, Aug 30, 2021 at 01:52:48PM +0200, Johan Hovold wrote:
Whether the API is better is debatable. As I said, almost no drivers use the new XArray interface, and perhaps partly because the new interface isn't as intuitive as has been claimed (e.g. xa_load() instead of ida_find()). And IDR/IDA isn't marked/documented as deprecated as far as I know.
I can't just slap a 'deprecated' attribute on it. That'll cause a storm of warnings. What would you suggest I do to warn people that this interface is deprecated and I would like to remove it?
I'd at least expect a suggestion in the IDR documentation to consider using XArray instead.
Fair enough.
+The IDR interface is deprecated; please use the `XArray`_ instead.
Just running that through htmldocs to make sure I've got the syntax right, and then I'll commit it.
Why do you think that idr_find() is more intuitive than xa_load()? The 'find' verb means that you search for something. But it doesn't search for anything; it just returns the pointer at that index. 'find' should return the next non-NULL pointer at-or-above a given index.
We're looking up a minor number which may or may not exist. "Find" (or "lookup" or "search") seems to describe this much better than "load" (even if that may better reflect the implementation of XArray).
It's not the _implementation_ that it fits, it's the _idiom_. The implementation is a lookup in a trie. The idiom of the XArray is that it's a sparse array, and so it's a load.
And no, I would not expect a find implementation to return the next entry if the requested entry does not exist (and neither does idr_find() or radix_tree_lookup()).
Oh dear. You've been corrupted by the bad naming of the IDR functions ;-(