Date: Wed, 28 Jan 2004 21:19:59 +0100
From: Andi Kleen <ak@suse.de>
To: Andi Kleen <ak@suse.de>
Cc: torvalds@osdl.org, 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 II
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On Wed, 28 Jan 2004 21:15:54 +0100
Andi Kleen <ak@suse.de> wrote:

>
> > 
> > Just set a flag aka "may need checking", and let the check be done by the 
> > actual "read_pcix_error()" code.
> 
> Where would you put the flag? 
> 
> Doing it global may give false errors for the wrong device with async MCEs
> and on SMP.
> 
> For putting it into the pci_dev you need to take logs to walk the list.
> If you delay it to a softirq for safely getting the lock it would be set too late.
> 
> Putting it into a different table indexed by pci index would be also racy 
> with hotplug.

... to follow up myself ...

I suppose moving the pci_dev lists to RCU could make the flag in pci-dev work. But it would be still
a bit tricky with preemptive kernels.

-Andi
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