linux/tools/include
Daniel Borkmann b1d9fc41aa 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 6d4339028b
("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 <edumazet@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 13:53:27 -04:00
..
asm tools: Provide a definition of WARN_ON 2017-01-27 21:29:39 -05:00
asm-generic radix tree test suite: Remove duplicate bitops code 2017-01-27 21:29:39 -05:00
linux bpf: add various verifier test cases for self-tests 2017-04-01 12:36:37 -07:00
tools tools: add more endian.h macros 2014-09-26 11:03:01 +02:00
uapi bpf: add napi_id read access to __sk_buff 2017-04-21 13:53:27 -04:00