Date: Wed, 28 Jan 2004 22:09:21 +0100
From: Andi Kleen <ak@suse.de>
To: Linus Torvalds <torvalds@osdl.org>
Cc: willy@debian.org, ishii.hironobu@jp.fujitsu.com,
       linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org
Subject: Re: [RFC/PATCH, 2/4] readX_check() performance evaluation
Message-Id: <20040128220921.7ba0bb78.ak@suse.de>
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On Wed, 28 Jan 2004 12:28:56 -0800 (PST)
Linus Torvalds <torvalds@osdl.org> wrote:

> 
> Alternatively, if you get a lot of information at MCE time (CPU that did
> the access + some device data), just queue up the information in a per-CPU
> queue. You don't have to worry about overflow - you can just drop if if 

That assumes that the access happened with preempt off ?

That's fine if it's guaranteed that the MCE still happened inside 
readl/writel. But if it's delayed longer for some reason there is no guarantee 
that you can find back to the CPU that caused the fault.

Putting it into the pci_dev and using RCU would be probably better.

-Andi
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