From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andy Zhou <azhou@ovn.org>
Subject: Re: [net-next sample action optimization v2 1/4] openvswitch:
 Deferred fifo API change.
Date: Thu, 16 Mar 2017 12:21:07 -0700
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Cc: Linux Kernel Network Developers <netdev@vger.kernel.org>,
        Joe Stringer <joe@ovn.org>
To: Pravin Shelar <pshelar@ovn.org>
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On Thu, Mar 16, 2017 at 10:28 AM, Pravin Shelar <pshelar@ovn.org> wrote:
> On Tue, Mar 14, 2017 at 4:08 PM, Andy Zhou <azhou@ovn.org> wrote:
>> add_deferred_actions() API currently requires actions to be passed in
>> as a fully encoded netlink message. So far both 'sample' and 'recirc'
>> actions happens to carry actions as fully encoded netlink messages.
>> However, this requirement is more restrictive than necessary, future
>> patch will need to pass in action lists that are not fully encoded
>> by themselves.
>
> It is not obvious why this change is required?
> can you explain it.

The original 'attr' requires a nested netlink message for the callee
to get the size of
the actions list.  In the sample case, since we rewrite sample into an
internal format that
does not have actions encoded as a nested netlink, we will need to
pass both pointer
to the first action, and the size of the actions list.