Re: [PATCH net-next] bpf: Add access to snd_cwnd and others in sock_ops

On 12/05/2017 01:21 AM, Lawrence Brakmo wrote:
[...]

    Just a question for clarification: do you need to have this in
    the uapi struct as well? Meaning, do you have a specific use case
    where you do this check out of the BPF program given the below
    two snd_cwnd/srtt_us check this internally in the ctx rewrite?
    
Although is_fullsock is checked internally, the bpf program may want to
verify if a return value of zero is due to a non fullsock state. The issue is
that there are some ops that are called from both active and passive paths
so it is not possible to know just by the op type.

Ok, fair point. Patch applied to bpf-next, thanks Lawrence!

    Do you plan to reuse the ctx assignment also for bpf_setsockopt()
    and bpf_getsockopt() internally?

If you mean, check is_fullsock instead of the call to sk_fullsock, then yes, it is
a great idea. However, I would rather do it in another patch so we don’t delay
this one (I have other things almost ready that depend on this patch).

That's fine by me.