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Date: Mon, 04 Dec 2000 15:08:29 -0800
From: Cedric Berger <cedric@wireless-networks.com>
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Subject: Re: Netgraph and SMP
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Mike Smith wrote:
> 
> The simplest structure for this is a shared/exclusive lock
> that supports intention; Terry would have ranted about this. (He would
> have called it a SIX-lock, I think).
> 
> In this model, you acquire the lock in 'shared' mode every time you enter
> Netgraph, and release it when you leave.
> 
> When you plan to make changes to Netgraph, you get the lock in
> 'exclusive' mode.  'Intention' comes in here; now that you are trying to
> get the lock in exclusive mode, your intention is recorded and nobody
> else can get it in 'shared' mode, so eventually all the users drain out
> of Netgraph and you get the lock.
> 

How is this SIX-pack lock any different than a standard reader-writer lock?

Cedric


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