From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH RFC]: napi_struct V4
Date: Wed, 25 Jul 2007 19:02:45 -0700 (PDT)
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From: Jeff Garzik <jeff@garzik.org>
Date: Wed, 25 Jul 2007 22:00:31 -0400

> David Miller wrote:
> > From: Jeff Garzik <jgarzik@pobox.com>
> > Date: Wed, 25 Jul 2007 21:55:08 -0400
> > 
> >> I don't see any logic to your request, only added overhead for no reason.
> > 
> > There may be some flawed logic in what Stephen stated, but
> > the change really is needed.
> > 
> > It must be atomic to execute the:
> > 
> > 	enable_interrupts();
> > 	netif_rx_complete();
> > 
> > sequence wrt. the same code path in the interrupt handler.
> 
> Sure.  And how did the existing code fail to achieve that?

The interrupt handler can run on another cpu in betwen those two
statements, running the NAPI test-and-do-something operations in
parallel with the netif_rx_complete() which causes problems as Rusty
and I discussed yesterday.