From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1755177Ab0DTUUl (ORCPT <rfc822;w@1wt.eu>);
	Tue, 20 Apr 2010 16:20:41 -0400
Received: from cantor2.suse.de ([195.135.220.15]:47860 "EHLO mx2.suse.de"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1755005Ab0DTUUk (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Tue, 20 Apr 2010 16:20:40 -0400
Date: Tue, 20 Apr 2010 13:16:42 -0700
From: Greg KH <gregkh@suse.de>
To: stefani@seibold.net
Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
       andi@firstfloor.org, alan@lxorguk.ukuu.org.uk, tytso@mit.edu,
       iws@ovro.caltech.edu
Subject: Re: [PATCH 0/4] enhanced reimplemention of the kfifo API
Message-ID: <20100420201642.GA32373@suse.de>
References: <1271794000-18897-1-git-send-email-stefani@seibold.net>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1271794000-18897-1-git-send-email-stefani@seibold.net>
User-Agent: Mutt/1.5.20 (2009-06-14)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Apr 20, 2010 at 10:06:36PM +0200, stefani@seibold.net wrote:
> From: Stefani Seibold <stefani@seibold.net>
> 
> This is a complete reimplementation of the new kfifo API, which is now 
> really generic, type save and type definable. 
> 
> The API is still stable, no code which use the current  kfifo API must 
> be modified!
> 
> Here are the results of the text section usage:
> 
> Example 1:
>                         kfifo_put/_get  kfifo_in/out    current kfifo
> dynamic allocated       0x000002a8      0x00000291      0x00000299
> in place                0x00000291      0x0000026e      0x00000273
> 
> kfifo.c                 new             old
> text section size       0x00000be5      0x000008b2
> 
> As you can see, kfifo_put/kfifo_get creates a little bit more code than 
> kfifo_in/kfifo_out, but it is much faster (the code is inline).
> 
> The code is complete hand crafted and optimized. The text section size is as 
> small as possible. You get all the fifo handling in only 3 kb. This includes 
> type safe fix size records, dynamic records and DMA handling.
> 
> This should be the final version. All requested features are implemented.
> 
> Note: Most features of this API doesn't have any users. All functions which
> are not used in the next 9 months will be removed. So, please adapt your
> drivers and other sources as soon as possible to the new API and post it. 
> 
> This are the features which are currently not used in the kernel:
> 
> kfifo_to_user()
> kfifo_from_user()
> kfifo_dma_....() macros
> kfifo_esize()
> kfifo_recsize()
> kfifo_put()
> kfifo_get()
> the fixed size record elements, exclude "unsigned char" fifo's and
> the variable size records fifo's

If you have features that have no users, why add them?  Do you think
that some drivers need/want these features?

thanks,

greg k-h