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Date: Sat, 28 Sep 2002 20:47:06 -0700
From: Andrew Morton <akpm@digeo.com>
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To: Andi Kleen <ak@suse.de>
CC: John Levon <levon@movementarian.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH][RFC] oprofile for 2.5.39
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Andi Kleen wrote:
> 
> smp_processor_id

Using smp_processor_id() is usually a bug.

Please default to using get_cpu()/put_cpu().

- It pins the caller onto that CPU if the kernel is preemptive.

- You may not sleep inside get_cpu/put_cpu.  

- If you do something which might sleep inside get_cpu/put_cpu,
  you get might_sleep() warnings.

Probably, smp_processor_id() needs to be renamed to something
which is hard to type.
-
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