From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Fastabend <john.r.fastabend@intel.com>
Subject: Re: ixgbe question
Date: Mon, 30 Nov 2009 12:20:15 -0800
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Cc: David Miller <davem@davemloft.net>,
	"Waskiewicz Jr, Peter P" <peter.p.waskiewicz.jr@intel.com>,
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To: Eric Dumazet <eric.dumazet@gmail.com>
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Eric Dumazet wrote:
> David Miller a =E9crit :
>  =20
>> From: John Fastabend <john.r.fastabend@intel.com>
>> Date: Tue, 24 Nov 2009 13:14:12 +0000
>>
>>    =20
>>> Believe the below patch will break DCB and FCoE though, both featur=
es
>>> have the potential to set real_num_tx_queues to greater then the
>>> number of CPUs.  This could result in real_num_tx_queues >
>>> num_tx_queues.
>>>
>>> The current solution isn't that great though, maybe we should set t=
o
>>> the minimum of MAX_TX_QUEUES and num_possible_cpus() * 2 + 8.
>>>
>>> That should cover the maximum possible queues for DCB, FCoE and the=
ir
>>> combinations.
>>>
>>> general multiq =3D num_possible_cpus()
>>> DCB =3D 8 tx queue's
>>> FCoE =3D 2*num_possible_cpus()
>>> FCoE + DCB =3D 8 tx queues + num_possible_cpus
>>>      =20
>> Eric, I'm tossing your patch because of this problem, just FYI.
>>    =20
>
> Sure, I guess we need a more generic way to handle this.
>
>  =20
Eric,

I'll resubmit your patch with a small update to fix my concerns soon.

thanks,
john.