From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Wiles, Keith" <keith.wiles@intel.com>
Subject: Re: [PATCH v1] [net/tap] add logic to assign speed from
 user
Date: Thu, 21 Dec 2017 13:38:25 +0000
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Cc: "dev@dpdk.org" <dev@dpdk.org>, "Yigit, Ferruh" <ferruh.yigit@intel.com>,
 "Patel, Amol" <amol.patel@intel.com>, "Hunt, David" <david.hunt@intel.com>,
 "Jain, Deepak K" <deepak.k.jain@intel.com>
To: "Varghese, Vipin" <vipin.varghese@intel.com>
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> On Dec 21, 2017, at 10:53 AM, Vipin Varghese <vipin.varghese@intel.com> w=
rote:
>=20
> TAP speed is passed as user argument, but never set to interface.
> New logic brings speed get and set to LOCAL and REMOTE interfaces.
>=20
> Updated the default PMD speeed to 10M as per Linux Kernel default
> value.

The problem in setting the link speed to 10M is that TAP will not limit its=
 traffic to 10M. Applications like pktgen and others use the Link speed to =
calculate the bit rate, which will be broken now.

I would suggest making the default value 10G or 40G instead as CPU speeds w=
ill continue to increase. Forcing someone to always add the link speed seem=
s a bit much when we know the systems can send/receive much higher then 10M=
, which is the reason 10G was picked. Please set the default back to 10G or=
 some much higher number.

>=20
> Signed-off-by: Vipin Varghese <vipin.varghese@intel.com>
> ---
> drivers/net/tap/rte_eth_tap.c | 185 +++++++++++++++++++++++++++++++++++++=
++++-
> 1 file changed, 182 insertions(+), 3 deletions(-)
>=20
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.=
c
> index 6b27679..7238504 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -62,6 +62,8 @@
> #include <linux/if_ether.h>
> #include <linux/version.h>
> #include <fcntl.h>
> +#include <linux/ethtool.h>
> +#include <linux/sockios.h>
>=20

Regards,
Keith