leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

net: ipv4 only populate IP_PKTINFO when needed

Browse Source 
The since the removal of the routing cache computing
fib_compute_spec_dst() does a fib_table lookup for each UDP multicast
packet received.  This has introduced a performance regression for some
UDP workloads.

This change skips populating the packet info for sockets that do not have
IP_PKTINFO set.

Benchmark results from a netperf UDP_RR test:
Before 89789.68 transactions/s
After  90587.62 transactions/s

Benchmark results from a fio 1 byte UDP multicast pingpong test
(Multicast one way unicast response):
Before 12.63us RTT
After  12.48us RTT

Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Shawn Bohrer
2013-10-07 11:01:40 -05:00
committed by David S. Miller
parent 421b3885bf
commit fbf8866d65
4 changed files with 6 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
include/net/ip.h
View File

@@ -459,7 +459,7 @@ int ip_options_rcv_srr(struct sk_buff *skb);
* Functions provided by ip_sockglue.c
*/
void ipv4_pktinfo_prepare(struct sk_buff *skb);
void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb);
void ip_cmsg_recv(struct msghdr *msg, struct sk_buff *skb);
int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc);
int ip_setsockopt(struct sock *sk, int level, int optname, char __user *optval,