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From: Thomas Monjalon <thomas.monjalon@6wind.com>
To: Matthew Hall <mhall@mhcomputing.net>, Helin Zhang <helin.zhang@intel.com>
Date: Thu, 24 Jul 2014 10:07:37 +0200
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Subject: Re: [dpdk-dev] [PATCH 3/5] i40e: support selecting hash functions
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2014-07-24 01:01, Matthew Hall:
> On Thu, Jul 24, 2014 at 09:59:23AM +0200, Thomas Monjalon wrote:
> > Is it really a good idea to configure this kind of thing at build time?
> > Maybe yes, I'm not sure.
> 
> Whether it's safe to set at runtime probably depends what happens to the card 
> if it gets changed. Do you have to reset the card or the port? Or is it OK if 
> it's more dynamic?

No, we can change configuration with rte_eth_dev_configure() before
initializing port. So it is truly configurable.
Requiring recompilation means it's not really configurable between 2 runs.
And it breaks binary packaging for Linux distributions.

Many things in DPDK are configured at build time. But we should wonder if
it's really a good design.

-- 
Thomas