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Date: Tue, 15 Apr 2008 09:09:23 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Peter Zijlstra <peterz@infradead.org>
cc: Bart Van Assche <bart.vanassche@gmail.com>,
       Andi Kleen <andi@firstfloor.org>, Roland Dreier <rdreier@cisco.com>,
       Ingo Molnar <mingo@elte.hu>, Matthew Wilcox <matthew@wil.cx>,
       Ingo Oeser <ioe-lkml@rameria.de>, Daniel Walker <dwalker@mvista.com>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Replace completions with semaphores
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On Tue, 15 Apr 2008, Peter Zijlstra wrote:
> 
> That sounds horrible; I really prefer targeted replacements like
> completions that make it clear what they're supposed to be used for.

I agree. I'd rather _keep_ the completions, and get rid of the semaphores, 
so I think the whole fundamental patch here under discussion is broken.

We should do:
 - continue replacing semaphores that are used purely for mutual exclusion 
   with mutexes.
 - probably add support for completions to do counting
 - and then eventually just do the _reverse_ of what the current patch 
   does, namely replace the existing counting semaphore usage with 
   completions.

Hmm?

		Linus