Re: [PATCH net-next] net: mana: Implement get_ringparam/set_ringparam for mana

[Simon Horman <horms@kernel.org>]

On Sun, Jul 14, 2024 at 08:40:20PM -0700, Shradha Gupta wrote:
> Currently the values of WQs for RX and TX queues for MANA devices
> are hardcoded to default sizes.
> Allow configuring these values for MANA devices as ringparam
> configuration(get/set) through ethtool_ops.
> 
> Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
> Reviewed-by: Long Li <longli@microsoft.com>

...

> diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
> index e39b8676fe54..3e27ca5155aa 100644
> --- a/include/net/mana/mana.h
> +++ b/include/net/mana/mana.h
> @@ -38,9 +38,21 @@ enum TRI_STATE {
>  
>  #define COMP_ENTRY_SIZE 64
>  
> -#define RX_BUFFERS_PER_QUEUE 512
> +/* This Max value for RX buffers is derived from __alloc_page()'s max page
> + * allocation calculation. It allows maximum 2^(MAX_ORDER -1) pages. RX buffer
> + * size beyond this value gets rejected by __alloc_page() call.
> + */
> +#define MAX_RX_BUFFERS_PER_QUEUE 8192
> +#define DEF_RX_BUFFERS_PER_QUEUE 512
> +#define MIN_RX_BUFFERS_PER_QUEUE 128
>  
> -#define MAX_SEND_BUFFERS_PER_QUEUE 256
> +/* This max value for TX buffers is dervied as the maximum allocatable

nit: derived

     Flagged by checkpatch --codespell



> + * pages supported on host per guest through testing. TX buffer size beyond
> + * this value is rejected by the hardware.
> + */
> +#define MAX_TX_BUFFERS_PER_QUEUE 16384
> +#define DEF_TX_BUFFERS_PER_QUEUE 256
> +#define MIN_TX_BUFFERS_PER_QUEUE 128
>  
>  #define EQ_SIZE (8 * MANA_PAGE_SIZE)
>  

...