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

[Jeffrey Hugo <quic_jhugo@quicinc.com>]

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@linaro.org>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>   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?