From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jianhua Xie <jianhua.xie@freescale.com>
Subject: Re: [PATCH 1/3] netdev: introduce new NETIF_F_HW_SWITCH_OFFLOAD feature
 flag for switch device offloads
Date: Fri, 5 Dec 2014 12:43:30 +0800
Message-ID: <548137F2.5080906@freescale.com>
References: <1417746401-8140-2-git-send-email-roopa@cumulusnetworks.com>
 <5481249E.7020902@freescale.com> <548131EB.3060502@cumulusnetworks.com>
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To: Roopa Prabhu <roopa@cumulusnetworks.com>
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=E5=9C=A8 2014=E5=B9=B412=E6=9C=8805=E6=97=A5 12:17, Roopa Prabhu =E5=86=
=99=E9=81=93:
> On 12/4/14, 7:21 PM, Jianhua Xie wrote:
>>
>> =E5=9C=A8 2014=E5=B9=B412=E6=9C=8805=E6=97=A5 10:26, roopa@cumulusne=
tworks.com =E5=86=99=E9=81=93:
>>> From: Roopa Prabhu <roopa@cumulusnetworks.com>
>>>
>>> This is a generic high level feature flag for all switch asic=20
>>> features today.
>>>
>>> switch drivers set this flag on switch ports. Logical devices like
>>> bridge, bonds, vxlans can inherit this flag from their slaves/ports=
=2E
>>>
>>> I had to use SWITCH in the name to avoid ambiguity with other featu=
re
>>> flags. But, since i have been harping about not calling it 'switch'=
,
>>> I am welcome to any suggestions :)
>>>
>>> An alternative to using a feature flag is to use a IFF_HW_OFFLOAD
>>> in net_device_flags.
>>> ---
>>>   include/linux/netdev_features.h |    2 ++
>>>   1 file changed, 2 insertions(+)
>>>
>>> diff --git a/include/linux/netdev_features.h=20
>>> b/include/linux/netdev_features.h
>>> index 8e30685..68db1de 100644
>>> --- a/include/linux/netdev_features.h
>>> +++ b/include/linux/netdev_features.h
>>> @@ -66,6 +66,7 @@ enum {
>>>       NETIF_F_HW_VLAN_STAG_FILTER_BIT,/* Receive filtering on VLAN=20
>>> STAGs */
>>>       NETIF_F_HW_L2FW_DOFFLOAD_BIT,    /* Allow L2 Forwarding in=20
>>> Hardware */
>>>       NETIF_F_BUSY_POLL_BIT,        /* Busy poll */
>>> +    NETIF_F_HW_SWITCH_OFFLOAD_BIT,  /* HW switch offload */
>> I am interested in this flag very much, but I am not very clear
>> how many offload capabilities does this flag imply.  If this flag
>> belongs to a general flag and can be accepted by all vendors,
>> I will reuse this flag to introduce another out going data traffics
>> distribution offload method to bonding driver.
> Right now its a one global offload flag for switch asics. Some may no=
t=20
> want to tune it more. But others may and so i do expect more flags in=
=20
> this category.
>
Got it with thanks.
Best Regards.
> Thanks,
> Roopa
>