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Subject: Re: [RFC PATCH] Fair low-latency rwlock v5
From: Peter Zijlstra <peterz@infradead.org>
To: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       "H. Peter Anvin" <hpa@zytor.com>, Jeremy Fitzhardinge <jeremy@goop.org>,
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Date: Mon, 25 Aug 2008 21:20:42 +0200
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On Sun, 2008-08-17 at 15:10 -0400, Mathieu Desnoyers wrote:

> Fair low-latency rwlock v5
> 
> Fair low-latency rwlock provides fairness for writers against reader threads,
> but lets softirq and irq readers in even when there are subscribed writers
> waiting for the lock. Writers could starve reader threads.

New lock types should come with lockdep support.

Also, if you're serious about -rt, you'll need to consider full PI.