On Fri, Dec 01, 2017 at 10:15:04AM -0800, Lawrence Brakmo wrote: > Adds read access to snd_cwnd and srtt_us fields of tcp_sock. Since these > fields are only valid if the socket associated with the sock_ops program > call is a full socket, the field is_fullsock is also added to the > bpf_sock_ops struct. If the socket is not a full socket, reading these > fields returns 0. > > Note that in most cases it will not be necessary to check is_fullsock to > know if there is a full socket. The context of the call, as specified by > the 'op' field, can sometimes determine whether there is a full socket. > > The struct bpf_sock_ops has the following fields added: > > __u32 is_fullsock; /* Some TCP fields are only valid if > * there is a full socket. If not, the > * fields read as zero. > */ > __u32 snd_cwnd; > __u32 srtt_us; /* Averaged RTT << 3 in usecs */ > > There is a new macro, SOCK_OPS_GET_TCP32(NAME), to make it easier to add > read access to more 32 bit tcp_sock fields. > > Signed-off-by: Lawrence Brakmo <bra...@fb.com>
lgtm Acked-by: Alexei Starovoitov <a...@kernel.org> will wait for Daniel to either ack it or apply it.
