From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ferruh Yigit <ferruh.yigit@intel.com>
Subject: Re: [PATCH] net/liquidio: do not touch mbuf initialized
	fields
Date: Fri, 9 Jun 2017 12:24:56 +0100
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Cc: Olivier Matz <olivier.matz@6wind.com>
To: Shijith Thotton <shijith.thotton@caviumnetworks.com>, dev@dpdk.org
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On 6/8/2017 12:22 PM, Shijith Thotton wrote:
> Avoid re-initializing of mbuf fields which are set while in pool.
> Replaced lio_recv_buffer_alloc with rte_pktmbuf_alloc.
> 
> See commit 8f094a9ac5d7 ("mbuf: set mbuf fields while in pool").
> 
> Signed-off-by: Shijith Thotton <shijith.thotton@caviumnetworks.com>

<...>

> @@ -489,9 +466,6 @@
>  			droq->refill_count++;
>  
>  			if (likely(nicbuf != NULL)) {
> -				nicbuf->data_off = RTE_PKTMBUF_HEADROOM;

Hi Shijith, Olivier,

nb_segs and next are initialized properly when mbuf allocated, but is
"data_off = RTE_PKTMBUF_HEADROOM" guaranteed?

> -				nicbuf->nb_segs = 1;
> -				nicbuf->next = NULL;
>  				/* We don't have a way to pass flags yet */
>  				nicbuf->ol_flags = 0;
>  				if (rh->r_dh.has_hash) {

<...>