Re: [PATCH RFC 1/3] xdp: Infrastructure to generalize XDP

On 16-09-20 06:00 PM, Tom Herbert wrote:

This patch creates an infrastructure for registering and running code at
XDP hooks in drivers. This is based on the orignal XDP?BPF and borrows
heavily from the techniques used by netfilter to make generic nfhooks.

An XDP hook is defined by the  xdp_hook_ops. This structure contains the
ops of an XDP hook. A pointer to this structure is passed into the XDP
register function to set up a hook. The XDP register function mallocs
its own xdp_hook_ops structure and copies the values from the
xdp_hook_ops passed in. The register function also stores the pointer
value of the xdp_hook_ops argument; this pointer is used in subsequently
calls to XDP to identify the registered hook.

The interface is defined in net/xdp.h. This includes the definition of
xdp_hook_ops, functions to register and unregister hook ops on a device
or individual instances of napi, and xdp_hook_run that is called by
drivers to run the hooks.

Tom,
perused the thread and it seems you are serious ;->
Are we heading towards Frankenstein Avenue?
The whole point behind letting in XDP is so that _small programs_
can be written to do some quick thing. eBPF 4K program limit was
touted as the check and bound. eBPF sounded fine.
This sounds like a huge contradiction.

cheers,
jamal