Re: [PATCH v5 3/8] ethdev: reserve capability flags for PMD-specific API

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

Hi Twei,

> -----Original Message-----
> From: Bie, Tiwei
> Sent: Wednesday, January 4, 2017 7:22 AM
> To: dev@dpdk.org
> Cc: adrien.mazarguil@6wind.com; Lu, Wenzhuo <wenzhuo.lu@intel.com>; Mcnamara, John <john.mcnamara@intel.com>;
> olivier.matz@6wind.com; thomas.monjalon@6wind.com; Ananyev, Konstantin <konstantin.ananyev@intel.com>; Zhang, Helin
> <helin.zhang@intel.com>; Dai, Wei <wei.dai@intel.com>; Wang, Xiao W <xiao.w.wang@intel.com>
> Subject: [PATCH v5 3/8] ethdev: reserve capability flags for PMD-specific API
> 
> Reserve a Tx capability flag and a Rx capability flag, that can be
> used by PMD to define its own capability flags when implementing the
> PMD-specific API.
> 
> Suggested-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
> Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
> Acked-by: Wenzhuo Lu <wenzhuo.lu@intel.com>
> ---
>  lib/librte_ether/rte_ethdev.h | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
> index d465825..8800b39 100644
> --- a/lib/librte_ether/rte_ethdev.h
> +++ b/lib/librte_ether/rte_ethdev.h
> @@ -857,6 +857,7 @@ struct rte_eth_conf {
>  #define DEV_RX_OFFLOAD_TCP_LRO     0x00000010
>  #define DEV_RX_OFFLOAD_QINQ_STRIP  0x00000020
>  #define DEV_RX_OFFLOAD_OUTER_IPV4_CKSUM 0x00000040
> +#define DEV_RX_OFFLOAD_RESERVED_0  0x00000080 /**< Used for PMD-specific API. */
> 
>  /**
>   * TX offload capabilities of a device.
> @@ -874,6 +875,7 @@ struct rte_eth_conf {
>  #define DEV_TX_OFFLOAD_GRE_TNL_TSO      0x00000400    /**< Used for tunneling packet. */
>  #define DEV_TX_OFFLOAD_IPIP_TNL_TSO     0x00000800    /**< Used for tunneling packet. */
>  #define DEV_TX_OFFLOAD_GENEVE_TNL_TSO   0x00001000    /**< Used for tunneling packet. */
> +#define DEV_TX_OFFLOAD_RESERVED_0  0x00002000 /**< Used for PMD-specific API. */
> 
>  /**
>   * Ethernet device information
> --
> 2.7.4

I am not sure how that supposed to work and how user should know that DEV_RX_OFFLOAD_RESERVED_0  
is actually a MACSEC for ixgbe?
Another question what to do if you would like to create a bonded device over two devices with different NIC types?
As I understand you can end up in situation when  DEV_RX_OFFLOAD_RESERVED_0  would mean different capabilities.
Why not to have this MACSEC capability and ol_flag value as generic ones, as you have them in previous versions of your patch?
Konstantin