Re: [PATCH RFC net-next 06/19] net: mvpp2: increase BM pool size to 2048 buffers

[Andrew Lunn]

On Sun, Jan 10, 2021 at 05:30:10PM +0200, stefanc@xxxxxxxxxxx wrote:
> From: Stefan Chulski <stefanc@xxxxxxxxxxx>
> 
> BM pool size increased to support Firmware Flow Control.
> Minimum depletion thresholds to support FC is 1024 buffers.
> BM pool size increased to 2048 to have some 1024 buffers
> space between depletion thresholds and BM pool size.
> 
> Signed-off-by: Stefan Chulski <stefanc@xxxxxxxxxxx>
> ---
>  drivers/net/ethernet/marvell/mvpp2/mvpp2.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
> index 89b3ede..8dc669d 100644
> --- a/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
> +++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2.h
> @@ -851,8 +851,8 @@ enum mvpp22_ptp_packet_format {
>  #define MVPP22_PTP_TIMESTAMPQUEUESELECT	BIT(18)
>  
>  /* BM constants */
> -#define MVPP2_BM_JUMBO_BUF_NUM		512
> -#define MVPP2_BM_LONG_BUF_NUM		1024
> +#define MVPP2_BM_JUMBO_BUF_NUM		2048
> +#define MVPP2_BM_LONG_BUF_NUM		2048

Hi Stefan

Jumbo used to be 1/2 of regular. Do you know why?

It would be nice to have a comment in the commit message about why it
is O.K. to change the ratio of jumbo to regular frames, and what if
anything this does for memory requirements.

	 Andrew