From: Calvin Walton <calvin.walton@kepstin.ca>
To: Christian Lamparter <chunkeey@googlemail.com>
Cc: linux-wireless@vger.kernel.org, linville@tuxdriver.com
Subject: Re: [PATCH] p54: Use do_div for 64-bit division to fix 32-bit kernels
Date: Wed, 07 Sep 2011 00:27:13 -0400 [thread overview]
Message-ID: <1315369635.3089.1.camel@ayu> (raw)
In-Reply-To: <201108252347.35706.chunkeey@googlemail.com>
On Thu, 2011-08-25 at 23:47 +0200, Christian Lamparter wrote:
> Use the do_div macro for 64-bit division. Otherwise, the module will
> reference __udivdi3 under 32-bit kernels, which is not allowed in
> kernel space.
>
> Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
> ---
> diff --git a/drivers/net/wireless/p54/txrx.c b/drivers/net/wireless/p54/txrx.c
> + do_div(survey->channel_time, 1024);
> + do_div(survey->channel_time_tx, 1024);
> + do_div(survey->channel_time_busy, 1024);
You're doing a division by a power of two here, why not just use a
bit-shift operation ">> 10" instead of a full division operation?
--
Calvin Walton <calvin.walton@kepstin.ca>
prev parent reply other threads:[~2011-09-07 4:27 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-08-25 21:47 [PATCH] p54: Use do_div for 64-bit division to fix 32-bit kernels Christian Lamparter
2011-09-07 4:27 ` Calvin Walton [this message]
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=1315369635.3089.1.camel@ayu \
--to=calvin.walton@kepstin.ca \
--cc=chunkeey@googlemail.com \
--cc=linux-wireless@vger.kernel.org \
--cc=linville@tuxdriver.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.