RE: [PATCH v3 bpf-next] bpf: devmap: move drop error path to devmap for XDP_REDIRECT

-----Original Message-----
From: Lorenzo Bianconi <lorenzo@kernel.org>
Sent: Monday, March 8, 2021 13:07
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Subject: [PATCH v3 bpf-next] bpf: devmap: move drop error path to devmap
for XDP_REDIRECT

We want to change the current ndo_xdp_xmit drop semantics because
it will allow us to implement better queue overflow handling.
This is working towards the larger goal of a XDP TX queue-hook.
Move XDP_REDIRECT error path handling from each XDP ethernet driver to
devmap code. According to the new APIs, the driver running the
ndo_xdp_xmit pointer, will break tx loop whenever the hw reports a tx
error and it will just return to devmap caller the number of successfully
transmitted frames. It will be devmap responsability to free dropped
frames.
Move each XDP ndo_xdp_xmit capable driver to the new APIs:
- veth
- virtio-net
- mvneta
- mvpp2
- socionext
- amazon ena
- bnxt
- freescale (dpaa2, dpaa)
- xen-frontend
- qede
- ice
- igb
- ixgbe
- i40e
- mlx5
- ti (cpsw, cpsw-new)
- tun
- sfc

Acked-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>

For the dpaa driver:
Reviewed-by: Camelia Groza <redacted>