From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: question about softirqs
Date: Wed, 13 May 2009 19:01:22 +0200
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Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>, netdev@vger.kernel.org,
	Ingo Molnar <mingo@elte.hu>,
	Steven Rostedt <rostedt@goodmis.org>, linuxppc-dev@ozlabs.org,
	Andi Kleen <andi@firstfloor.org>, paulus@samba.org,
	Thomas Gleixner <tglx@linutronix.de>, David Miller <davem@davemloft.net>
To: Chris Friesen <cfriesen@nortel.com>
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On Wed, May 13, 2009 at 09:05:01AM -0600, Chris Friesen wrote:
> Andi Kleen wrote:
> > Thomas Gleixner <tglx@linutronix.de> writes:
> 
> >>Err, no. Chris is completely correct:
> >>
> >>        if (!in_interrupt())
> >>		wakeup_softirqd();
> > 
> > Yes you have to wake it up just in case, but it doesn't normally
> > process the data because a normal softirq comes in faster. It's
> > just a safety policy. 
> 
> What about the scenario I raised earlier, where we have incoming network
> packets,

network packets are normally processed by the network packet interrupt's
softirq or alternatively in the NAPI poll loop.

-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.