From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ian Campbell <Ian.Campbell@eu.citrix.com>
Subject: Re: [PATCH 1/4] net: convert core to skb paged frag APIs
Date: Wed, 24 Aug 2011 08:49:56 +0100
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On Tue, 2011-08-23 at 19:34 +0100, Micha=C5=82 Miros=C5=82aw wrote:
> 2011/8/23 Ian Campbell <ian.campbell@citrix.com>:
> > +               for (i =3D 0; i < skb_shinfo(skb)->nr_frags; i++) {
> > +                       skb_frag_t *frag =3D &skb_shinfo(skb)->frag=
s[i];
>=20
> This is a rather common construct, so it might be worth it to
> introduce something like for_each_skb_frag().

I agree. My first stab at this helper (which was untenable for other
reasons, I never posted it) had such a helper. I decided not to tackle
it on this pass since it touches a bunch of places which even this
enormous series doesn't. I've got it on my list to do some time after
this series as a cleanup though.

Some places want the frag nr and others want the skb_frag_t* so I think
you'd end up with
	for_each_skb_frag(skb, frag) { ... }
and
	for_each_skb_frag_nr(skb, i) { ... }
a few places use both frag and i within the loop but not enough to
warrant an explicit helper, I don't think.

An "skb_frag(skb, i)" helper for the &skb_shinfo(skb)->frags[i]
construct might be nice too.

Ian.