From: Duncan Sands <baldrick@free.fr>
To: Stelian Pop <stelian@popies.net>
Subject: Re: [RFC, 2.6] a simple FIFO implementation
Date: Fri, 17 Sep 2004 15:16:24 +0200
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Cc: Hugh Dickins <hugh@veritas.com>, Andrew Morton <akpm@osdl.org>,
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References: <20040917102413.GA3089@crusoe.alcove-fr> <200409171500.35499.baldrick@free.fr> <20040917130532.GA22386@sd291.sivit.org>
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> > Hi Stelian, what is to stop the compiler putting, say, "in" in a register
> > for the process calling __kfifo_get, so that it only sees a constant
> > value.  Then after a while that process will think there is nothing
> > to get even though another process is shoving stuff into the fifo and
> > modifying "in".
> 
> This can happen all right, but the buffer (or the indices) will not
> get corrupt (this is what I call coherent). Its just like the __kfifo_get()
> was executed entirely before the __kfifo_put().

Hi Stelian, that's not how I read the comment

+ * Note that with only one concurrent reader and one concurrent 
+ * writer, you don't need extra locking to use these functions.

so maybe it is better to avoid confusion and be more explicit here.

Ciao,

Duncan.
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