Currently, all bearers are configured with MTU value same as the
underlying L2 device. However, in case of bearers with media type
UDP, higher throughput is possible with a fixed and higher emulated
MTU value than adapting to the underlying L2 MTU.
In this commit, we introduce a parameter mtu in struct tipc_media
and a default value is set for UDP. A default value of 14k
was determined by experimentation and found to have a higher throughput
than 16k. MTU for UDP bearers are assigned the above set value of
media MTU.
Acked-by: Ying Xue <ying....@windriver.com>
Acked-by: Jon Maloy <jon.ma...@ericsson.com>
Signed-off-by: GhantaKrishnamurthy MohanKrishna
<mohan.krishna.ghanta.krishnamur...@ericsson.com>
---
include/uapi/linux/tipc_config.h | 5 +++++
net/tipc/udp_media.c | 4 ++--
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/tipc_config.h b/include/uapi/linux/tipc_config.h
index 3f29e3c8ed06..4b2c93b1934c 100644
--- a/include/uapi/linux/tipc_config.h
+++ b/include/uapi/linux/tipc_config.h
@@ -185,6 +185,11 @@
#define TIPC_DEF_LINK_WIN 50
#define TIPC_MAX_LINK_WIN 8191
+/*
+ * Default MTU for UDP media
+ */
+
+#define TIPC_DEF_LINK_UDP_MTU 14000
struct tipc_node_info {
__be32 addr; /* network address of node */
diff --git a/net/tipc/udp_media.c b/net/tipc/udp_media.c
index e7d91f5d5cae..9783101bc4a9 100644
--- a/net/tipc/udp_media.c
+++ b/net/tipc/udp_media.c
@@ -713,8 +713,7 @@ static int tipc_udp_enable(struct net *net, struct
tipc_bearer *b,
err = -EINVAL;
goto err;
}
- b->mtu = dev->mtu - sizeof(struct iphdr)
- - sizeof(struct udphdr);
+ b->mtu = b->media->mtu;
#if IS_ENABLED(CONFIG_IPV6)
} else if (local.proto == htons(ETH_P_IPV6)) {
udp_conf.family = AF_INET6;
@@ -803,6 +802,7 @@ struct tipc_media udp_media_info = {
.priority = TIPC_DEF_LINK_PRI,
.tolerance = TIPC_DEF_LINK_TOL,
.window = TIPC_DEF_LINK_WIN,
+ .mtu = TIPC_DEF_LINK_UDP_MTU,
.type_id = TIPC_MEDIA_TYPE_UDP,
.hwaddr_len = 0,
.name = "udp"
--
2.1.4
