linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: David Laight <David.Laight@ACULAB.COM>
Cc: "'Crt Mori'" <cmo@melexis.com>,
	Jonathan Cameron <jic23@kernel.org>,
	Ingo Molnar <mingo@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Kees Cook <keescook@chromium.org>,
	Rusty Russell <rusty@rustcorp.com.au>,
	Ian Abbott <abbotti@mev.co.uk>,
	Larry Finger <Larry.Finger@lwfinger.net>,
	Niklas Soderlund <niklas.soderlund+renesas@ragnatech.se>,
	Thomas Gleixner <tglx@linutronix.de>,
	Krzysztof Kozlowski <krzk@kernel.org>,
	Masahiro Yamada <yamada.masahiro@socionext.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-iio@vger.kernel.org" <linux-iio@vger.kernel.org>,
	Joe Perches <joe@perches.com>
Subject: Re: [PATCH v10 1/3] lib: Add strongly typed 64bit int_sqrt
Date: Wed, 20 Dec 2017 17:00:01 +0100	[thread overview]
Message-ID: <20171220160001.manjff26gfbjccsw@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <1c1d0ffa8ee140bf9adbc78f1559b1e8@AcuMS.aculab.com>

On Wed, Dec 20, 2017 at 02:39:26PM +0000, David Laight wrote:

> With minor changes it ought to be possible to remove most of the
> 64bit arithmetic and shifts.
> 
> If you care about performance then using 32 bit maths will be much faster.

Some, u64 add/sub/shift isn't exactly expensive, but yes, I also
indicated that improvement is possible. At the very least y can be made
a u32 I suppose.

  parent reply	other threads:[~2017-12-20 16:00 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-20 14:20 [PATCH v10 1/3] lib: Add strongly typed 64bit int_sqrt Crt Mori
2017-12-20 14:39 ` David Laight
2017-12-20 15:41   ` Crt Mori
2017-12-20 16:00   ` Peter Zijlstra [this message]
2017-12-20 16:17     ` Crt Mori
2017-12-20 16:46       ` David Laight
2017-12-20 17:19         ` Joe Perches
2017-12-21 10:02           ` David Laight
2017-12-20 17:30         ` Crt Mori
2017-12-21 10:08           ` David Laight
2017-12-21 10:59           ` David Laight
2017-12-21 11:43           ` David Laight
2017-12-21 13:17             ` Crt Mori
2017-12-21 13:56               ` David Laight
2017-12-21 14:11                 ` Peter Zijlstra
2017-12-21 14:48                   ` David Laight
2017-12-22 13:44                     ` Crt Mori
2018-01-09 15:18                       ` Crt Mori
2018-01-12  9:41                         ` David Laight
2018-01-15  8:17                           ` Crt Mori

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=20171220160001.manjff26gfbjccsw@hirez.programming.kicks-ass.net \
    --to=peterz@infradead.org \
    --cc=David.Laight@ACULAB.COM \
    --cc=Larry.Finger@lwfinger.net \
    --cc=abbotti@mev.co.uk \
    --cc=akpm@linux-foundation.org \
    --cc=cmo@melexis.com \
    --cc=jic23@kernel.org \
    --cc=joe@perches.com \
    --cc=keescook@chromium.org \
    --cc=krzk@kernel.org \
    --cc=linux-iio@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@kernel.org \
    --cc=niklas.soderlund+renesas@ragnatech.se \
    --cc=rusty@rustcorp.com.au \
    --cc=tglx@linutronix.de \
    --cc=yamada.masahiro@socionext.com \
    /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).