From: Subash Abhinov Kasiviswanathan Date: Sun, 7 Jan 2018 18:36:35 +0000 (-0700) Subject: net: qualcomm: rmnet: Set pacing shift X-Git-Tag: v4.19~1702^2~225^2~5 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4e8683a95c963d766c7341eddbbc2d0c20022ebf;p=platform%2Fkernel%2Flinux-rpi3.git net: qualcomm: rmnet: Set pacing shift The real device over which the rmnet devices are installed also aggregate multiple IP packets and sends them as a single large aggregate frame to the hardware. This causes degraded throughput for TCP TX due to bufferbloat. To overcome this problem, pacing shift value of 8 is set using the sk_pacing_shift_update() helper. This value was determined based on experiments with a single stream TCP TX using iperf for a duration of 30s. Pacing shift | Observed data rate (Mbps) 10 | 9 9 | 140 8 | 146 (Max link rate) Signed-off-by: Subash Abhinov Kasiviswanathan Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c index 8e1f43a..8f8c4f2 100644 --- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c @@ -16,6 +16,7 @@ #include #include #include +#include #include "rmnet_private.h" #include "rmnet_config.h" #include "rmnet_vnd.h" @@ -204,6 +205,8 @@ void rmnet_egress_handler(struct sk_buff *skb) struct rmnet_priv *priv; u8 mux_id; + sk_pacing_shift_update(skb->sk, 8); + orig_dev = skb->dev; priv = netdev_priv(orig_dev); skb->dev = priv->real_dev;