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From: Thomas Monjalon <thomas.monjalon@6wind.com>
To: "Ananyev, Konstantin" <konstantin.ananyev@intel.com>
Date: Wed, 09 Mar 2016 15:25:52 +0100
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Subject: Re: [dpdk-dev] [PATCH v2 1/2] ethdev: add buffered tx api
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2016-03-09 13:36, Ananyev, Konstantin:
> > > +   if (to_send == 0)
> > > +           return 0;
> > 
> > Why this check is done in the lib?
> > What is the performance gain if we are idle?
> > It can be done outside if needed.
> 
> Yes, that could be done outside, but if user has to do it anyway,
> why not to put it inside?
> I don't expect any performance gain/loss because of that -
> just seems a bit more convenient to the user.

It is handling an idle case so there is no gain obviously.
But the condition branching is surely a loss.
So why the user would you like to do this check?