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Date: Sat, 23 Aug 2008 11:02:19 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
       "H. Peter Anvin" <hpa@zytor.com>, Jeremy Fitzhardinge <jeremy@goop.org>,
       Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>,
       Joe Perches <joe@perches.com>, linux-kernel@vger.kernel.org,
       Steven Rostedt <rostedt@goodmis.org>
Subject: Re: [RFC PATCH] Writer-biased low-latency rwlock v8
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On Sat, 23 Aug 2008, Mathieu Desnoyers wrote:
> 
> Now, let me explain why I need at least not one, but _four different_
> contention bits. Simply because there are four types of contention, one
> for each execution context which may take the read lock. (irq, softirq,
> non-preemptable, preemptable)

No. You need _one_ contention bit in the fast-path.

Then, as you get into the slow-path, you can decide on four different 
behaviours.

Quite frankly, I don't think this discussion is going anywhere. I don't 
think I'd take anything from you, since you seem to have a really hard 
time separating out the issue of fast-path and slow-path. So I'm simply 
not going to bother, and I'm not going to expect to merge your work. 

Sorry, but it simply isn't worth my time or effort.

			Linus