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Date: Fri, 4 Mar 2016 10:11:54 +0800
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: "Xie, Huawei" <huawei.xie@intel.com>
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Cc: "Michael S. Tsirkin" <mst@redhat.com>, "dev@dpdk.org" <dev@dpdk.org>,
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Subject: Re: [dpdk-dev] [PATCH v2 1/7] vhost: refactor
	rte_vhost_dequeue_burst
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On Thu, Mar 03, 2016 at 05:19:42PM +0000, Xie, Huawei wrote:
> On 2/18/2016 9:48 PM, Yuanhan Liu wrote:
> > [...]
> CCed changchun, the author for the chained handling of desc and mbuf.
> The change makes the code more readable, but i think the following
> commit message is simple and enough.

Hmm.., my commit log tells a full story:

- What is the issue? (messy/logic twisted code)

- What the code does? (And what are the challenges: few tricky places)

- What's the proposed solution to fix it. (the below pseudo code)

And you suggest me to get rid of the first 2 items and leave 3rd item
(a solution) only?

	--yliu

> >
> > 	while (this_desc_is_not_drained_totally || has_next_desc) {
> > 		if (this_desc_has_drained_totally) {
> > 			this_desc = next_desc();
> > 		}
> >
> > 		if (mbuf_has_no_room) {
> > 			mbuf = allocate_a_new_mbuf();
> > 		}
> >
> > 		COPY(mbuf, desc);
> > 	}
> >
> > [...]
> >
> > This refactor makes the code much more readable (IMO), yet it reduces
> > binary code size (nearly 2K).
> I guess the reduced binary code size comes from reduced inline calls to
> mbuf allocation.
>