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Date: Wed, 16 Apr 2008 10:08:49 -0700
From: Arjan van de Ven <arjan@infradead.org>
To: Matthew Wilcox <matthew@wil.cx>
Cc: Oliver Neukum <oliver@neukum.org>, Ingo Oeser <ioe-lkml@rameria.de>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Andi Kleen <andi@firstfloor.org>, Peter Zijlstra <peterz@infradead.org>,
       Bart Van Assche <bart.vanassche@gmail.com>,
       Roland Dreier <rdreier@cisco.com>, Ingo Molnar <mingo@elte.hu>,
       Daniel Walker <dwalker@mvista.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Replace completions with semaphores
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On Wed, 16 Apr 2008 10:58:11 -0600
Matthew Wilcox <matthew@wil.cx> wrote:

> On Wed, Apr 16, 2008 at 09:50:26AM -0700, Arjan van de Ven wrote:
> > yup. For kcounters there is a clear owner for each "slot".
> > [This is the part that makes it debugable again)
> > 
> > Now for non-debug builds, the space taken for the token can be..
> > zero depending on how we define the types for it.
> 
> Hm.  That might be worth changing the API for.  Right now, I'm
> overloading the return value of kcounter_claim with an errno and a
> cookie.  Maybe we should go for:
> 
> extern int __must_check kcounter_claim(struct kcounter *kc,
> kcounter_cookie_t *resource);
> 
> with the return value being 0 or errno and on success, kcounter_claim
> writes a cookie to 'resource'?

or we return a cookie, and define some sort of "cookie_is_error()" thing

> 


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