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Date: Fri, 27 Mar 2015 19:09:27 +0100
Message-ID: <CAJuTgQUKMYOE7XBxUPG=amYi1zSJ-7FVk92uf4pVbGimtymXMw@mail.gmail.com>
Subject: Re: [RFC PATCH 07/11] IB/Verbs: Use management helper has_mcast()
 and, cap_mcast() for mcast-check
From: Yun Wang <yun.wang@profitbricks.com>
To: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
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On Fri, Mar 27, 2015 at 6:49 PM, Jason Gunthorpe
<jgunthorpe@obsidianresearch.com> wrote:
> On Fri, Mar 27, 2015 at 06:31:26PM +0100, Yun Wang wrote:
>
>> Maybe we can temporarily reserve the old logical, and gradually solve
>> these problems?
>
> It is best to make behavioral changes in small patches, yes.
>
> I think it is best to address these sorts of problems before trying to
> tackle the driver interface side - that will avoid complexity.
>
> ie how does a driver set has_ipoib? It isn't even a sensible question
> when it is a per port capability.

I used to imaging it would like:

init_device_mgmt_attributs(device)
{
    for_each_port(device)
        if (port support XX) {
            port.mgmt_attribute |= CAP_XX
             if !(device.mgmt_attribute & HAS_XX)
                 device.mgmt_attribute |= HAS_XX
        }
}

That is incase if a device got one port have some capability, the
device have it too, so has_XX() will check on device level that if it
has any port support XX, and cap_XX() to check on port level.

But if has_XX() is only for optimizing the init/exit path, then it
doesn't make sense to me any more...

Regards,
Michael Wang

>
> Jason