Re: Designing a safe RX-zero-copy Memory Model for Networking

On Tue, 13 Dec 2016, Hannes Frederic Sowa wrote:

quoted

Interesting.  So you even imagine sockets registering memory regions
with the NIC.  If we had a proper NIC HW filter API across the drivers,
to register the steering rule (like ibv_create_flow), this would be
doable, but we don't (DPDK actually have an interesting proposal[1])

On a side note, this is what windows does with RIO ("registered I/O").
Maybe you want to look at the API to get some ideas: allocating and
pinning down memory in user space and registering that with sockets to
get zero-copy IO.

Yup that is also what I think. Regarding the memory registration and flow
steering for user space RX/TX ring please look at the qpair model
implemented by the RDMA subsystem in the kernel. The memory semantics are
clearly established there and have been in use for more than a decade.