[dpdk-dev,v2,1/6] ethdev: add an field for querying hash key size

  To support querying hash key size per port, an new field of
'hash_key_size' was added in 'struct rte_eth_dev_info' for storing
hash key size in bytes.

Signed-off-by: Helin Zhang <helin.zhang@intel.com>
---
 lib/librte_ether/rte_ethdev.h | 3 +++
 1 file changed, 3 insertions(+)

v2 changes:
* Disabled the code changes by default, to avoid breaking ABI compatibility.
  

Hi Helin,

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Helin Zhang
> Sent: Thursday, June 04, 2015 8:34 AM
> To: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH v2 1/6] ethdev: add an field for querying hash key size
> 
> To support querying hash key size per port, an new field of
> 'hash_key_size' was added in 'struct rte_eth_dev_info' for storing
> hash key size in bytes.
> 
> Signed-off-by: Helin Zhang <helin.zhang@intel.com>
> ---
>  lib/librte_ether/rte_ethdev.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> v2 changes:
> * Disabled the code changes by default, to avoid breaking ABI compatibility.
> 
> diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
> index 16dbe00..bdebc87 100644
> --- a/lib/librte_ether/rte_ethdev.h
> +++ b/lib/librte_ether/rte_ethdev.h
> @@ -916,6 +916,9 @@ struct rte_eth_dev_info {
>  	uint16_t max_vmdq_pools; /**< Maximum number of VMDq pools. */
>  	uint32_t rx_offload_capa; /**< Device RX offload capabilities. */
>  	uint32_t tx_offload_capa; /**< Device TX offload capabilities. */
> +#ifdef RTE_QUERY_HASH_KEY_SIZE
> +	uint8_t hash_key_size; /**< Hash key size in bytes */
> +#endif
>  	uint16_t reta_size;
>  	/**< Device redirection table size, the total number of entries. */
>  	/** Bit mask of RSS offloads, the bit offset also means flow type */

Why do you need to introduce an #ifdef RTE_QUERY_HASH_KEY_SIZE
around your code?
Why not to have it always on?
Is it because of not breaking ABI for 2.1?
But here, I suppose there would be no breakage anyway:

struct rte_eth_dev_info {
...
        uint32_t tx_offload_capa; /**< Device TX offload capabilities. */
        uint16_t reta_size;
        /**< Device redirection table size, the total number of entries. */
        /** Bit mask of RSS offloads, the bit offset also means flow type */
        uint64_t flow_type_rss_offloads;
        struct rte_eth_rxconf default_rxconf;
 

so between 'reta_size' and 'flow_type_rss_offloads', there is a 2 bytes gap.
Wonder, why not put it there?

Konstantin

> --
> 1.9.3
  

> -----Original Message-----
> From: Ananyev, Konstantin
> Sent: Thursday, June 4, 2015 6:38 PM
> To: Zhang, Helin; dev@dpdk.org
> Subject: RE: [dpdk-dev] [PATCH v2 1/6] ethdev: add an field for querying hash
> key size
> 
> Hi Helin,
> 
> > -----Original Message-----
> > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Helin Zhang
> > Sent: Thursday, June 04, 2015 8:34 AM
> > To: dev@dpdk.org
> > Subject: [dpdk-dev] [PATCH v2 1/6] ethdev: add an field for querying
> > hash key size
> >
> > To support querying hash key size per port, an new field of
> > 'hash_key_size' was added in 'struct rte_eth_dev_info' for storing
> > hash key size in bytes.
> >
> > Signed-off-by: Helin Zhang <helin.zhang@intel.com>
> > ---
> >  lib/librte_ether/rte_ethdev.h | 3 +++
> >  1 file changed, 3 insertions(+)
> >
> > v2 changes:
> > * Disabled the code changes by default, to avoid breaking ABI compatibility.
> >
> > diff --git a/lib/librte_ether/rte_ethdev.h
> > b/lib/librte_ether/rte_ethdev.h index 16dbe00..bdebc87 100644
> > --- a/lib/librte_ether/rte_ethdev.h
> > +++ b/lib/librte_ether/rte_ethdev.h
> > @@ -916,6 +916,9 @@ struct rte_eth_dev_info {
> >  	uint16_t max_vmdq_pools; /**< Maximum number of VMDq pools. */
> >  	uint32_t rx_offload_capa; /**< Device RX offload capabilities. */
> >  	uint32_t tx_offload_capa; /**< Device TX offload capabilities. */
> > +#ifdef RTE_QUERY_HASH_KEY_SIZE
> > +	uint8_t hash_key_size; /**< Hash key size in bytes */ #endif
> >  	uint16_t reta_size;
> >  	/**< Device redirection table size, the total number of entries. */
> >  	/** Bit mask of RSS offloads, the bit offset also means flow type */
> 
> Why do you need to introduce an #ifdef RTE_QUERY_HASH_KEY_SIZE around
> your code?
> Why not to have it always on?
> Is it because of not breaking ABI for 2.1?
> But here, I suppose there would be no breakage anyway:
> 
> struct rte_eth_dev_info {
> ...
>         uint32_t tx_offload_capa; /**< Device TX offload capabilities. */
>         uint16_t reta_size;
>         /**< Device redirection table size, the total number of entries. */
>         /** Bit mask of RSS offloads, the bit offset also means flow type */
>         uint64_t flow_type_rss_offloads;
>         struct rte_eth_rxconf default_rxconf;
> 
> 
> so between 'reta_size' and 'flow_type_rss_offloads', there is a 2 bytes gap.
> Wonder, why not put it there?
Oh, yes, you are totally right. There should be a 2 bytes padding there.
I will rework it with that. Thanks!

Helin

> 
> Konstantin
> 
> > --
> > 1.9.3