af_packet: Add Queue mapping mode to af_packet fanout operation
This patch adds a queue mapping mode to the fanout operation of af_packet
sockets. This allows user space af_packet users to better filter on flows
ingressing and egressing via a specific hardware queue, and avoids the potential
packet reordering that can occur when FANOUT_CPU is being used and irq affinity
varies.
Tested successfully by myself. applies to net-next
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 9734616..6a2bb37 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1312,6 +1312,13 @@
return idx;
}
+static unsigned int fanout_demux_qm(struct packet_fanout *f,
+ struct sk_buff *skb,
+ unsigned int num)
+{
+ return skb_get_queue_mapping(skb) % num;
+}
+
static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
{
return f->flags & (flag >> 8);
@@ -1351,6 +1358,9 @@
case PACKET_FANOUT_RND:
idx = fanout_demux_rnd(f, skb, num);
break;
+ case PACKET_FANOUT_QM:
+ idx = fanout_demux_qm(f, skb, num);
+ break;
case PACKET_FANOUT_ROLLOVER:
idx = fanout_demux_rollover(f, skb, 0, (unsigned int) -1, num);
break;
@@ -1421,6 +1431,7 @@
case PACKET_FANOUT_LB:
case PACKET_FANOUT_CPU:
case PACKET_FANOUT_RND:
+ case PACKET_FANOUT_QM:
break;
default:
return -EINVAL;