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Subject: Re: fsl booke MM vs. SMP questions
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Dave Liu <r63238@freescale.com>
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Date: Wed, 23 May 2007 13:08:56 +1000
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On Wed, 2007-05-23 at 10:38 +0800, Dave Liu wrote:
> On Wed, 2007-05-23 at 08:42 +1000, Benjamin Herrenschmidt wrote:
> 
> > The IPIs should be buffered by the PIC ... delivered only once but
> 
> but what is the buffer depth for IPIs in the PIC?

One :-)

You never "loose" IPIs in the sense that you always get at least 1
interrupt for N IPIs and it's up to software to make sure not to lose
any event. The linux kernel arch code usually handles that with a
synchronous IPI mecanism.

Ben.