redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

udp: prefetch rmem_alloc in udp_queue_rcv_skb() 

On UDP packets processing, if the BH is the bottle-neck, it
always sees a cache miss while updating rmem_alloc; try to
avoid it prefetching the value as soon as we have the socket
available.

Performances under flood with multiple NIC rx queues used are
unaffected, but when a single NIC rx queue is in use, this
gives ~10% performance improvement.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hifive-unleashed-5.1
Paolo Abeni 2017-06-21 10:24:40 +02:00 committed by David S. Miller
parent da2e9cf03b
commit dd99e425be
1 changed files with 1 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
net/ipv4/udp.c
View File

@ -1949,6 +1949,7 @@ static int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
}
}
prefetch(&sk->sk_rmem_alloc);
if (rcu_access_pointer(sk->sk_filter) &&
udp_lib_checksum_complete(skb))
goto csum_error;