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From: "David S. Miller" <davem@redhat.com>
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Date: Wed, 21 Mar 2001 01:41:25 -0800 (PST)
To: Keith Owens <kaos@ocs.com.au>
Cc: nigel@nrg.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH for 2.5] preemptible kernel 
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Keith Owens writes:
 > Or have I missed something?

Nope, it is a fundamental problem with such kernel pre-emption
schemes.  As a result, it would also break our big-reader locks
(see include/linux/brlock.h).

Basically, anything which uses smp_processor_id() would need to
be holding some lock so as to not get pre-empted.

Later,
David S. Miller
davem@redhat.com
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