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From:   Jose Abreu <Jose.Abreu@synopsys.com>
To:     David Miller <davem@davemloft.net>,
        "jakub.kicinski@netronome.com" <jakub.kicinski@netronome.com>
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Subject: RE: [PATCH net-next v2 04/12] net: stmmac: Add Split Header support
 and enable it in XGMAC cores
Thread-Topic: [PATCH net-next v2 04/12] net: stmmac: Add Split Header support
 and enable it in XGMAC cores
Thread-Index: AQHVUPKdBvuj8ZjSi0+3V315mYCFAKb4AawAgAC8LGA=
Date:   Tue, 13 Aug 2019 08:30:47 +0000
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++ Jakub

From: David Miller <davem@davemloft.net>
Date: Aug/12/2019, 22:06:18 (UTC+00:00)

> From: Jose Abreu <Jose.Abreu@synopsys.com>
> Date: Mon, 12 Aug 2019 11:44:03 +0200
>=20
> > 	- Add performance info (David)
>=20
> Ummm...
>=20
> Whilst cpu utilization is interesting, I might be mainly interested in
> how this effects "networking" performance.  I find it very surprising
> that it isn't obvious that this is what I wanted.
>=20
> Do you not do performance testing on the networking level when you
> make fundamental changes to how packets are processed by the
> hardware/driver?

I do.

In my HW this feature does not impact performance neither improves it as=20
I'm already on max of theoretical bandwidth.

I do expect it to reduce CPU usage and memory footprint because we no=20
longer have to memcpy the entire buffer to SKB and instead we just copy=20
the header and then append payload as page which is passed directly to=20
net layer.

This feature is already used in some drivers and is part of GRO=20
offloading I think.

Jakub, as David is off can you please comment on how can we proceed with=20
this series ? I can add more information in commit log for this patch=20
...

---
Thanks,
Jose Miguel Abreu