From a4dfa72d0acd1c99a160e25c099849ae37ad13fd Mon Sep 17 00:00:00 2001 From: GhantaKrishnamurthy MohanKrishna Date: Thu, 19 Apr 2018 11:06:18 +0200 Subject: [PATCH] tipc: set default MTU for UDP media 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 Acked-by: Jon Maloy Signed-off-by: GhantaKrishnamurthy MohanKrishna Signed-off-by: David S. Miller --- 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" -- 2.11.0