Re: [PATCH 1/2] kfifo: round up the fifo size power of 2

[Stefani Seibold <stefani@seibold.net>]

Am Freitag, den 26.10.2012, 20:33 +0800 schrieb Yuanhan Liu:
> On Fri, Oct 26, 2012 at 11:30:27AM +0200, Stefani Seibold wrote:
> > Am Freitag, den 26.10.2012, 15:56 +0800 schrieb Yuanhan Liu:
> > > Say, if we want to allocate a filo with size of 6 bytes, it would be safer
> > > to allocate 8 bytes instead of 4 bytes.
> > > ----
> > > I know it works with rounddown_pow_of_two as well, since size is maintained
> > > in the kfifo internal part. But, I'm quite curious why Stefani chose
> > > rounddown_pow_of_two. To reduce memory?
> > > 
> > 
> > Yes, exactly, if a user do the wrong thing, than the user will get also
> > a wrong result, and did not waste memory.
> 
> But, isn't it better to 'correct' it? ;-)

Both is wrong. This depends on the view. For me it is better to get less
and don't wast space. For example: requesting 1025 will yield in your
case to a fifo which 2048 elements, which requires double of the memory
as expected.

> 
> > 
> > But anyway, if the majority like this patch it is okay for me.
> 
> Sorry, do you mean you are OK with this patch?
> 

I depends not on me, ask for a democratic decisions.

Greetings,
Stefani