From mboxrd@z Thu Jan  1 00:00:00 1970
From: Zoltan Kiss <zoltan.kiss@linaro.org>
Subject: Re: [PATCH v2] ixgbe: fix check for split packets
Date: Wed, 22 Jul 2015 10:47:34 +0100
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To: Bruce Richardson <bruce.richardson@intel.com>, dev@dpdk.org
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Hi,

And what happens if someone changes RTE_IXGBE_VPMD_RX_BURST to something 
else than 32? I guess this bug were introduced when someone raised it 
from 16 to 32
I think you are better off with a for loop which uses this value. Or at 
least make a comment around RTE_IXGBE_VPMD_RX_BURST that if you change 
that value this check should be modified as well.

Regards,

Zoltan

On 22/07/15 10:13, Bruce Richardson wrote:
> The check for split packets to be reassembled in the vector ixgbe PMD
> was incorrectly only checking the first 16 elements of the array instead
> of all 32. This is fixed by changing the uint32_t values to be uint64_t
> instead.
>
> Fixes: cf4b4708a88a ("ixgbe: improve slow-path perf with vector scattered Rx")
>
> Reported-by: Zoltan Kiss <zoltan.kiss@linaro.org>
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
>
> ---
> V2: Rename variable from split_fl32 to split_fl64 to match type change.
> ---
>   drivers/net/ixgbe/ixgbe_rxtx_vec.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/ixgbe/ixgbe_rxtx_vec.c b/drivers/net/ixgbe/ixgbe_rxtx_vec.c
> index d3ac74a..f2052c6 100644
> --- a/drivers/net/ixgbe/ixgbe_rxtx_vec.c
> +++ b/drivers/net/ixgbe/ixgbe_rxtx_vec.c
> @@ -549,10 +549,10 @@ ixgbe_recv_scattered_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
>   		return 0;
>
>   	/* happy day case, full burst + no packets to be joined */
> -	const uint32_t *split_fl32 = (uint32_t *)split_flags;
> +	const uint64_t *split_fl64 = (uint64_t *)split_flags;
>   	if (rxq->pkt_first_seg == NULL &&
> -			split_fl32[0] == 0 && split_fl32[1] == 0 &&
> -			split_fl32[2] == 0 && split_fl32[3] == 0)
> +			split_fl64[0] == 0 && split_fl64[1] == 0 &&
> +			split_fl64[2] == 0 && split_fl64[3] == 0)
>   		return nb_bufs;
>
>   	/* reassemble any packets that need reassembly*/
>