On Sun, Jun 30, 2019 at 07:32:14PM +0300, Ilias Apalodimas wrote:
On Sun, Jun 30, 2019 at 07:25:53PM +0300, Ivan Khoronzhuk wrote:
On Sat, Jun 29, 2019 at 08:23:25AM +0300, Ilias Apalodimas wrote:
>The interface only supports 1 Tx queue so locking is introduced on
>the Tx queue if XDP is enabled to make sure .ndo_start_xmit and
>.ndo_xdp_xmit won't corrupt Tx ring
>
>- Performance (SMMU off)
>
>Benchmark XDP_SKB XDP_DRV
>xdp1 291kpps 344kpps
>rxdrop 282kpps 342kpps
>
>- Performance (SMMU on)
>Benchmark XDP_SKB XDP_DRV
>xdp1 167kpps 324kpps
>rxdrop 164kpps 323kpps
>
>Signed-off-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
>---
>drivers/net/ethernet/socionext/netsec.c | 361 ++++++++++++++++++++++--
>1 file changed, 334 insertions(+), 27 deletions(-)
>
[...]
>+
>+static int netsec_xdp_setup(struct netsec_priv *priv, struct bpf_prog *prog,
>+ struct netlink_ext_ack *extack)
>+{
>+ struct net_device *dev = priv->ndev;
>+ struct bpf_prog *old_prog;
>+
>+ /* For now just support only the usual MTU sized frames */
>+ if (prog && dev->mtu > 1500) {
>+ NL_SET_ERR_MSG_MOD(extack, "Jumbo frames not supported on XDP");
>+ return -EOPNOTSUPP;
>+ }
>+
>+ if (netif_running(dev))
>+ netsec_netdev_stop(dev);
And why to stop the interface. XDP allows to update prog in runtime.
Adding the support is not limited to adding a prog only in this driver.
It also rebuilts the queues which changes the dma mapping of buffers.
Since i don't want to map BIDIRECTIONAL buffers if XDP is not in place,
i am resetting the device and forcing the buffer re-allocation
Thanks
/Ilias
I don't know the internals, probably it has some dependencies, but here you
just update the prog and can at least do it when exchange is happening.
I mean not in case of prog is attached/removed first time.
In case of prog -> prog it seems doable...
It ups to you ofc, but I can run smth like:
ip -force link set dev eth0 xdp obj xdp-example-pass.o sec .text
and expect it's updated w/o interface reset I mean on new prog.
I'm not sure, but maintainers can help, conceptually it's supposed to be in
runtime the prog be update uder rcu as a part of API usage...
--
Regards,
Ivan Khoronzhuk
