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Date: Tue, 27 Nov 2001 12:52:26 +0100 (CET)
From: Ingo Molnar <mingo@elte.hu>
Reply-To: <mingo@elte.hu>
To: Robert Love <rml@tech9.net>
Cc: linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] proc-based cpu affinity user interface
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On 26 Nov 2001, Robert Love wrote:

> Attached is my procfs-based implementation of a user interface for
> getting and setting a task's CPU affinity.  Patch is against 2.4.16.

two comments. First, this has already been done - Andrew Morton has
written such a patch.

Second, as i've repeatedly said it, it's a failure to do this over /proc.
What if /proc is not mounted? What if the process is in a chroot()
environment, should it not be able to set its own affinity? This is a
fundamental limitation of your approach, and *if* we want to export the
cpus_allowed affinity to user-space (which is up to discussion), then the
right way (TM) to do it is via a syscall.

	Ingo

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