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Message-ID: <1329314906.2437.36.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC>
Subject: Re: [PATCH] char random: fix boot id uniqueness race (v2)
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>, linux-kernel@vger.kernel.org,
        Matt Mackall <mpm@selenic.com>, Greg Kroah-Hartman <greg@kroah.com>
Date: Wed, 15 Feb 2012 15:08:26 +0100
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Le mercredi 15 février 2012 à 08:35 -0500, Mathieu Desnoyers a écrit :

> That would make sense, as long as we're OK about turning a read-mostly
> operation into a fully serialized operation that requires to exchange
> the lock between processor cache-lines. But as you point out, it should
> be fairly unfrequently used.
> 
> Any particular reason to use a spin lock rather than a mutex ? I did put
> a mutex in my implementation assuming that it would be a little more
> RT-friendly.

generate_random_uuid(uuid) is very fast and doesnt sleep.