Re: [PATCH 0/4] enhanced reimplemention of the kfifo API

[Greg KH <gregkh@suse.de>]

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