Subject: Re: [RFC][PATCH] irq_work
From: Peter Zijlstra <peterz@infradead.org>
To: Huang Ying <ying.huang@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>, "H.PeterA" <"nvin hpa"@zytor.com>,
       linux-kernel@vger.kernel.org, Andi Kleen <andi@firstfloor.org>
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Date: Thu, 24 Jun 2010 08:58:00 +0200
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On Thu, 2010-06-24 at 14:50 +0800, Huang Ying wrote:
> On Thu, 2010-06-24 at 14:47 +0800, Peter Zijlstra wrote:
> > On Thu, 2010-06-24 at 14:43 +0800, Huang Ying wrote:
> > > Hi, Peter,
> > 
> > > I fact I uses exactly the similar method in my patches, just trigger it
> > > with soft_irq instead of IRQ. Please take a look at
> > > nmi_return_notifier_schedule in
> > 
> > But then why still use softirq? Once you have this its completely
> > useless.
> 
> Some systems have no self interrupt, for example the system without
> APIC. We need to provide a fallback for them. soft_irq can help here.

So there's systems that don't have self-ipi but do have NMI context?

Can't we run the callbacks from the tick or something for such legacy
muck? I really don't like the whole softirq mess.
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