From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bruce Richardson Subject: Re: [PATCH] net/mlx5: return RSS hash result in mbuf Date: Tue, 27 Sep 2016 15:11:10 +0100 Message-ID: <20160927141110.GC36420@bricha3-MOBL3> References: <42701f77fcdb03c88ea845071c0710797cfaa549.1473840791.git.nelio.laranjeiro@6wind.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: dev@dpdk.org, Adrien Mazarguil To: Nelio Laranjeiro Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id A91002904 for ; Tue, 27 Sep 2016 16:11:14 +0200 (CEST) Content-Disposition: inline In-Reply-To: <42701f77fcdb03c88ea845071c0710797cfaa549.1473840791.git.nelio.laranjeiro@6wind.com> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Wed, Sep 14, 2016 at 10:16:05AM +0200, Nelio Laranjeiro wrote: > Signed-off-by: Nelio Laranjeiro > --- > drivers/net/mlx5/mlx5_rxq.c | 1 + > drivers/net/mlx5/mlx5_rxtx.c | 6 +++++- > drivers/net/mlx5/mlx5_rxtx.h | 2 ++ > 3 files changed, 8 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/mlx5/mlx5_rxq.c b/drivers/net/mlx5/mlx5_rxq.c > index f6f4315..65c264b 100644 > --- a/drivers/net/mlx5/mlx5_rxq.c > +++ b/drivers/net/mlx5/mlx5_rxq.c > @@ -926,6 +926,7 @@ rxq_ctrl_setup(struct rte_eth_dev *dev, struct rxq_ctrl *rxq_ctrl, > .rxq = { > .elts_n = log2above(desc), > .mp = mp, > + .rss_hash = !!(priv->rxqs_n > 1), > }, Two comments on this: 1. I don't think the !! is needed, since this is a comparison which will result in 0 or 1, rather than an int value that needs to be clamped to those values. 2. Why limit the use of RSS to when there is more than one RX queues? Sometimes it might be useful to have a precomputed hash for a packet even when not spreading packets among RX queues. For example, when using a single RX queue, but doing a hash table lookup for each packet, the RSS value could be used as the lookup hash. /Bruce