Re: [RFC, 2.6] a simple FIFO implementation

[Stelian Pop]

On Fri, Sep 17, 2004 at 02:37:57PM +0200, Duncan Sands wrote:

> > + * Note that with only one concurrent reader and one concurrent 
> > + * writer, you don't need extra locking to use these functions.
>                                  ^^^^^ which functions? (ambiguous)

Well, the same comment is for two adjacent functions, so I don't
think it's so ambiguous. Or s/these/this/ if you prefer.

> And what does "extra locking" mean?

Some kind of locking, like the one the wrapper kfifo_get/kfifo_put
propose.

> > +	len = min(len, fifo->size - fifo->in + fifo->out);
> 
> After all, since you are reading both in and out here, some kind of
> locking is needed.

But the order in which in and out get modified guarantees that you
will still have a coherent content (provided the assignments are 
atomic, which they are).

Stelian.
-- 
Stelian Pop <stelian@xxxxxxxxxx>    
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