From: Daniel Phillips <phillips@istop.com>
To: Andi Kleen <ak@suse.de>
Subject: Re: RFC: i386: kill !4KSTACKS
Date: Tue, 6 Sep 2005 18:36:07 -0400
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Cc: Giridhar Pemmasani <giri@lmc.cs.sunysb.edu>, linux-kernel@vger.kernel.org
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On Tuesday 06 September 2005 18:21, Andi Kleen wrote:
> On Wednesday 07 September 2005 00:19, Daniel Phillips wrote:
> > Andi, their stack will have to have a valid thread_info->task because
> > interrupts will use it.  Out of interest, could you please explain what
> > for?
>
> No, with 4k interrupts run on their own stack with their own thread_info
> Or rather they mostly do. Currently do_IRQ does irq_enter which refers
> thread_info before switching to the interrupt stack, that order would
> likely need to be exchanged.

But then how would thread_info->task on the irq stack ever get initialized?

My "what for" question was re why interrupt routines even need a valid 
current.  I see one answer out there on the web: statistical profiling.  Is 
that it?

Regards,

Daniel
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