tree b2d075990b32e8c21129851bf1b1adf4cdc441f1
parent d6f144830bdfa5fcf116e9ab8fc6a60d23fa623d
author Eric Dumazet <eric.dumazet@gmail.com> 1321499606 +0000
committer David S. Miller <davem@davemloft.net> 1321567568 -0500

net: use jump_label to shortcut RPS if not setup

Most machines dont use RPS/RFS, and pay a fair amount of instructions in
netif_receive_skb() / netif_rx() / get_rps_cpu() just to discover
RPS/RFS is not setup.

Add a jump_label named rps_needed.

If no device rps_map or global rps_sock_flow_table is setup,
netif_receive_skb() / netif_rx() do a single instruction instead of many
ones, including conditional jumps.

jmp +0    (if CONFIG_JUMP_LABEL=y)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>