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To: Yongseok Koh <yskoh@mellanox.com>
Cc: stable@dpdk.org, shahafs@mellanox.com
References: <20190430202227.36167-1-yskoh@mellanox.com>
From: Kevin Traynor <ktraynor@redhat.com>
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 (mx1.redhat.com [10.5.110.49]); Wed, 01 May 2019 09:43:00 +0000 (UTC)
Subject: Re: [dpdk-stable] [PATCH 18.11] net/mlx5: fix instruction hotspot
 on replenishing Rx buffer
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On 30/04/2019 21:22, Yongseok Koh wrote:
> On replenishing Rx buffers for vectorized Rx, mbuf->buf_addr isn't needed
> to be accessed as it is static and easily calculated from the mbuf address.
> Accessing the mbuf content causes unnecessary load stall. non-x86
> processors (mostly RISC such as ARM and Power) are more vulnerable to load
> stall. For x86, reducing the number of instructions seems to matter most.
> 
> Fixes: 545b884b1da3 ("net/mlx5: fix buffer address posting in SSE Rx")
> 
> Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
> Acked-by: Shahaf Shuler <shahafs@mellanox.com>

Thanks. Added a reference to the dpdk master commits in the commit msg
and queued for 18.11 stable branch. Will push to dpdk-stable next week
as part of next batch.