All of lore.kernel.org
 help / color / mirror / Atom feed
From: Patrick McHardy <kaber@trash.net>
To: Stephen Hemminger <shemminger@vyatta.com>
Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org
Subject: Re: [PATCH 2/4] dsmark: get rid of trivial function
Date: Mon, 21 Jan 2008 01:16:32 +0100	[thread overview]
Message-ID: <4793E460.5020804@trash.net> (raw)
In-Reply-To: <20080120132550.056370c0@deepthought>

Stephen Hemminger wrote:
> Replace loop in dsmark_valid_indices with equivalent bit math.
> 
> Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
> 
> --- a/net/sched/sch_dsmark.c	2008-01-20 13:07:58.000000000 -0800
> +++ b/net/sched/sch_dsmark.c	2008-01-20 13:22:54.000000000 -0800
> @@ -45,13 +45,8 @@ struct dsmark_qdisc_data {
>  
>  static inline int dsmark_valid_indices(u16 indices)
>  {
> -	while (indices != 1) {
> -		if (indices & 1)
> -			return 0;
> -		indices >>= 1;
> -	}
> -
> -	return 1;
> +	/* Must have only one bit set */
> +	return (indices & (indices - 1)) == 0;


hweight seems easier to understand, it took me a bit
to realize that the comment matches the code :)

  reply	other threads:[~2008-01-21  0:16 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20080120130542.16720b45@deepthought>
2008-01-20 21:25 ` [PATCH 2/4] dsmark: get rid of trivial function Stephen Hemminger
2008-01-21  0:16   ` Patrick McHardy [this message]
2008-01-21  8:39     ` Ilpo Järvinen
2008-01-21 10:22     ` David Miller
2008-01-22  3:47       ` Stephen Hemminger
2008-01-22  3:59         ` David Miller

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=4793E460.5020804@trash.net \
    --to=kaber@trash.net \
    --cc=davem@davemloft.net \
    --cc=netdev@vger.kernel.org \
    --cc=shemminger@vyatta.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.