Re: [PATCH 3/3] net: mhi: Increase the default MTU from 16K to 32K

From: Jeffrey Hugo
Date: Tue Jun 06 2023 - 09:51:22 EST


On 6/6/2023 6:31 AM, Manivannan Sadhasivam wrote:
Most of the Qualcomm endpoint devices are supporting 32K MTU for the
UL (Uplink) and DL (Downlink) channels. So let's use the same value
in the MHI NET driver also. This gives almost 2x increase in the throughput
for the UL channel.

Below is the comparision:

iperf on the UL channel with 16K MTU:

[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 353 MBytes 296 Mbits/sec

iperf on the UL channel with 32K MTU:

[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 695 MBytes 583 Mbits/sec

Cc: Loic Poulain <loic.poulain@xxxxxxxxxx>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
---
drivers/net/mhi_net.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/mhi_net.c b/drivers/net/mhi_net.c
index 3d322ac4f6a5..eddc2c701da4 100644
--- a/drivers/net/mhi_net.c
+++ b/drivers/net/mhi_net.c
@@ -14,7 +14,7 @@
#define MHI_NET_MIN_MTU ETH_MIN_MTU
#define MHI_NET_MAX_MTU 0xffff
-#define MHI_NET_DEFAULT_MTU 0x4000
+#define MHI_NET_DEFAULT_MTU 0x8000

Why not SZ_32K?