From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: netif_tx_disable and lockless TX
Date: Wed, 31 May 2006 00:08:18 -0700 (PDT)
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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Wed, 31 May 2006 16:31:52 +1000

> On Tue, May 30, 2006 at 11:26:26PM -0700, David Miller wrote:
> > 
> > I don't think it will be worthwhile to keep NAPI around just for
> > TX completion.  Sure the dev_kfree_skb() will schedule software
> > interrupt work to do the actual free, but the TX ring walking
> > and dev_kfree_skb() calls will be in hard IRQ context.
> 
> Sure we won't need all of NAPI.  But would it be that bad to schedule
> a tasklet to do the TX completion?

It seems just an extra level of indirection. :)

> Oh, I'm not proposing that we disable IRQs on xmit_lock at all.
 ...

I understand what you're saying.  What I'm talking about is that in
net channel drivers we might go back to IRQ disabling locks again.