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Date: Wed, 21 Mar 2001 10:18:38 -0800 (PST)
From: Nigel Gamble <nigel@nrg.org>
Reply-To: nigel@nrg.org
To: "David S. Miller" <davem@redhat.com>
cc: Keith Owens <kaos@ocs.com.au>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH for 2.5] preemptible kernel
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On Wed, 21 Mar 2001, David S. Miller wrote:
> Basically, anything which uses smp_processor_id() would need to
> be holding some lock so as to not get pre-empted.

Not necessarily.  Another solution for the smp_processor_id() case is
to ensure that the task can only be scheduled on the current CPU for the
duration that the value of smp_processor_id() is used.  Or, if the
critical region is very short, to disable interrupts on the local CPU.

Nigel Gamble                                    nigel@nrg.org
Mountain View, CA, USA.                         http://www.nrg.org/

MontaVista Software                             nigel@mvista.com

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