Date: Thu, 16 Sep 2004 06:57:50 -0700
From: Paul Jackson <pj@sgi.com>
To: Stelian Pop <stelian@popies.net>
Cc: akpm@osdl.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC, 2.6] a simple FIFO implementation
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This still has a 'size' attribute.  As Andrew noted,
this might not be needed.

See for example:

  http://cse.stanford.edu/class/cs110/handouts/27Queues.pdf

for coding a fifo queue with just a put and get pointer.

The queue is empty if put == get, and it is full if adding one more
would make it empty.  The number of elements in the queue can be done
using modulo arithmetic on the difference between put and get (or what
the above *.pdf file and your code calls head and tail), with no
distinct 'size' element.   The head and tail wrap.

-- 
                          I won't rest till it's the best ...
                          Programmer, Linux Scalability
                          Paul Jackson <pj@sgi.com> 1.650.933.1373
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