From b1d9fc41aab11f9520b2e0d57ae872e2ec5d6f32 Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Wed, 19 Apr 2017 23:01:17 +0200 Subject: bpf: add napi_id read access to __sk_buff Add napi_id access to __sk_buff for socket filter program types, tc program types and other bpf_convert_ctx_access() users. Having access to skb->napi_id is useful for per RX queue listener siloing, f.e. in combination with SO_ATTACH_REUSEPORT_EBPF and when busy polling is used, meaning SO_REUSEPORT enabled listeners can then select the corresponding socket at SYN time already [1]. The skb is marked via skb_mark_napi_id() early in the receive path (e.g., napi_gro_receive()). Currently, sockets can only use SO_INCOMING_NAPI_ID from 6d4339028b35 ("net: Introduce SO_INCOMING_NAPI_ID") as a socket option to look up the NAPI ID associated with the queue for steering, which requires a prior sk_mark_napi_id() after the socket was looked up. Semantics for the __sk_buff napi_id access are similar, meaning if skb->napi_id is < MIN_NAPI_ID (e.g. outgoing packets using sender_cpu), then an invalid napi_id of 0 is returned to the program, otherwise a valid non-zero napi_id. [1] http://netdevconf.org/2.1/slides/apr6/dumazet-BUSY-POLLING-Netdev-2.1.pdf Suggested-by: Eric Dumazet Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- tools/include/uapi/linux/bpf.h | 1 + 1 file changed, 1 insertion(+) (limited to 'tools/include') diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 1e062bb..e553529 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -603,6 +603,7 @@ struct __sk_buff { __u32 tc_classid; __u32 data; __u32 data_end; + __u32 napi_id; }; struct bpf_tunnel_key { -- cgit v1.1