From: "Nélio Laranjeiro" <nelio.laranjeiro@6wind.com>
To: Bruce Richardson <bruce.richardson@intel.com>
Cc: dev@dpdk.org, Adrien Mazarguil <adrien.mazarguil@6wind.com>
Subject: Re: [dpdk-dev] [PATCH] net/mlx5: return RSS hash result in mbuf
Date: Tue, 27 Sep 2016 16:29:49 +0200 [thread overview]
Message-ID: <20160927142949.GE32397@autoinstall.dev.6wind.com> (raw)
In-Reply-To: <20160927141110.GC36420@bricha3-MOBL3>
Hi Bruce,
On Tue, Sep 27, 2016 at 03:11:10PM +0100, Bruce Richardson wrote:
> On Wed, Sep 14, 2016 at 10:16:05AM +0200, Nelio Laranjeiro wrote:
> > Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>
> > ---
> > 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.
Ok for this one.
> 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
ConnectX-4 NICs does not return a hash value for a single queue as
software does not request RSS in this situation, that is why it is not
filled.
I will send a v2 to also fix a bug discovered since concerning the hash
result which is not retrieve from the right place when Completion Queue
Entry is compressed.
Regards,
--
Nélio Laranjeiro
6WIND
next prev parent reply other threads:[~2016-09-27 14:29 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-14 8:16 Nelio Laranjeiro
2016-09-14 8:16 ` Nelio Laranjeiro
2016-09-23 9:15 ` Adrien Mazarguil
2016-09-27 14:11 ` Bruce Richardson
2016-09-27 14:29 ` Nélio Laranjeiro [this message]
2016-09-27 14:53 ` [dpdk-dev] [PATCH v2] " Nelio Laranjeiro
2016-09-27 17:03 ` Ferruh Yigit
2016-09-28 7:01 ` Nélio Laranjeiro
2016-09-28 7:02 ` [dpdk-dev] [PATCH v3] " Nelio Laranjeiro
2016-09-28 8:59 ` Adrien Mazarguil
2016-09-28 12:11 ` [dpdk-dev] [PATCH v4] " Nelio Laranjeiro
2016-10-12 15:12 ` Bruce Richardson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160927142949.GE32397@autoinstall.dev.6wind.com \
--to=nelio.laranjeiro@6wind.com \
--cc=adrien.mazarguil@6wind.com \
--cc=bruce.richardson@intel.com \
--cc=dev@dpdk.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).