[ovs-dev] [PATCHv3] lib: upgrade to DPDK v1.8.0

[Kavanagh, Mark B]

> -----Original Message-----
> From: Ben Pfaff [mailto:blp at nicira.com]
> Sent: Tuesday, February 17, 2015 9:51 PM
> To: Kavanagh, Mark B
> Cc: dev at openvswitch.org
> Subject: Re: [ovs-dev] [PATCHv3] lib: upgrade to DPDK v1.8.0
> 
> I'll leave the main review here to Pravin, but I did notice one thing.
> There's a comment here that talks about how something changed.  That's
> useful enough to someone who knows how it was before, but it's a
> little unfriendly to new readers.  I prefer comments to talk about the
> current state of affairs instead, unless the history is really
> relevant.  In this case it's only a really minor wording difference.
> So I'd change this:
> 
> On Tue, Feb 17, 2015 at 09:20:04PM +0000, Mark Kavanagh wrote:
> > +/* DPDK 1.8 makes significant changes to struct rte_ mbuf that impact OVS.
> > + * Chief among these is the replacement of the 'data' pointer (previously used
> > + * to store an ofpbuf's data) with an offset field - the data pointer may be
> > + * calculated by adding the data_off to the mbuf segment address. This breaks
> 
> to something more like this:
> 
>     In DPDK 1.8, struct rte_mbuf lacks a direct pointer to a packet's
>     data.  Instead, it has a segment address and an offset field, whose
>     sum is the data pointer.  This breaks...
> 
> which is only slightly different wording but IMO more friendly to
> newcomers.  If you did want to emphasize the history then you could
> add a few more words at the beginning:
> 
>     Unlike earlier versions, in DPDK 1.8, struct rte_mbuf lacks a
>     direct pointer to a packet's data.  Instead, it has a segment
>     address and an offset field, whose sum is the data pointer.  This
>     breaks...

Good point Ben, I'll update the relevant comment and the commit message with any rework suggested by Pravin.