From: Matthew Wilcox <willy@infradead.org>
To: Johan Hovold <johan@kernel.org>
Cc: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>,
Alex Elder <elder@kernel.org>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
greybus-dev@lists.linaro.org, linux-staging@lists.linux.dev,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v4] staging: greybus: Convert uart.c from IDR to XArray
Date: Mon, 30 Aug 2021 14:31:35 +0100 [thread overview]
Message-ID: <YSzdtzH1GdZqt66G@casper.infradead.org> (raw)
In-Reply-To: <YSzQAd0Rg5CF/eLe@hovoldconsulting.com>
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
;-(
next prev parent reply other threads:[~2021-08-30 13:32 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-29 9:22 [PATCH v4] staging: greybus: Convert uart.c from IDR to XArray Fabio M. De Francesco
2021-08-30 9:12 ` Johan Hovold
2021-08-30 11:10 ` Fabio M. De Francesco
2021-08-30 11:52 ` Johan Hovold
2021-08-30 12:16 ` Matthew Wilcox
2021-08-30 12:33 ` Johan Hovold
2021-08-30 13:16 ` Fabio M. De Francesco
2021-08-30 13:20 ` [greybus-dev] " Alex Elder
2021-08-31 8:07 ` Johan Hovold
2021-08-31 10:42 ` Alex Elder
2021-08-31 11:51 ` Johan Hovold
2021-08-31 11:50 ` Fabio M. De Francesco
2021-08-31 12:18 ` Johan Hovold
2021-09-01 12:09 ` Alex Elder
2021-09-01 13:56 ` Fabio M. De Francesco
2021-09-01 14:29 ` Matthew Wilcox
2021-09-01 15:39 ` Fabio M. De Francesco
2021-08-30 13:31 ` Matthew Wilcox [this message]
2021-08-31 8:16 ` Johan Hovold
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YSzdtzH1GdZqt66G@casper.infradead.org \
--to=willy@infradead.org \
--cc=elder@kernel.org \
--cc=fmdefrancesco@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=greybus-dev@lists.linaro.org \
--cc=johan@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-staging@lists.linux.dev \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).