Re: [dpdk-dev] [RFC PATCH 3/4] add support for a ring to be a pktdev

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

Hi Bruce,

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Bruce Richardson
> Sent: Friday, April 17, 2015 4:17 PM
> To: dev@dpdk.org; Wiles, Keith
> Subject: [dpdk-dev] [RFC PATCH 3/4] add support for a ring to be a pktdev
> 
> Add a new public API function, and two internal wrapper functions so we
> can use ring as a pktdev.
> ---
>  lib/librte_ring/rte_ring.c | 41 +++++++++++++++++++++++++++++++++++++++++
>  lib/librte_ring/rte_ring.h |  3 +++
>  2 files changed, 44 insertions(+)
> 
> diff --git a/lib/librte_ring/Makefile b/lib/librte_ring/Makefile
> index 84ad3d3..bc5dd09 100644
> --- a/lib/librte_ring/Makefile
> +++ b/lib/librte_ring/Makefile
> @@ -47,6 +47,6 @@ SRCS-$(CONFIG_RTE_LIBRTE_RING) := rte_ring.c
>  SYMLINK-$(CONFIG_RTE_LIBRTE_RING)-include := rte_ring.h
> 
>  # this lib needs eal and rte_malloc
> -DEPDIRS-$(CONFIG_RTE_LIBRTE_RING) += lib/librte_eal lib/librte_malloc
> +DEPDIRS-$(CONFIG_RTE_LIBRTE_RING) += lib/librte_eal lib/librte_malloc lib/librte_pktdev
> 
>  include $(RTE_SDK)/mk/rte.lib.mk
> diff --git a/lib/librte_ring/rte_ring.c b/lib/librte_ring/rte_ring.c
> index c9e59d4..424da20 100644
> --- a/lib/librte_ring/rte_ring.c
> +++ b/lib/librte_ring/rte_ring.c
> @@ -86,6 +86,7 @@
>  #include <rte_errno.h>
>  #include <rte_string_fns.h>
>  #include <rte_spinlock.h>
> +#include <rte_pktdev.h>

I don't think it is a good idea to make rte_ring dependent on rte_pktdev (or rte_ethdev).  
If we'd like to have pkt (or eth) device based on rte_ring, why not to create librte_pmd_ring
and put all that stuff there?  
Konstantin

> 
>  #include "rte_ring.h"
> 
> @@ -208,6 +208,47 @@ rte_ring_create(const char *name, unsigned count, int socket_id,
>  	return r;
>  }
> 
> +static uint16_t
> +dev_rx(void *r, struct rte_mbuf **pkts, uint16_t max_pkts)
> +{
> +	return rte_ring_dequeue_burst(r, (void *)pkts, max_pkts);
> +}
> +
> +static uint16_t
> +dev_tx(void *r, struct rte_mbuf **pkts, uint16_t max_pkts)
> +{
> +	return rte_ring_enqueue_burst(r, (void *)pkts, max_pkts);
> +}
> +
> +#define rte_ring_dev_data rte_pkt_dev_data
> +
> +struct rte_pkt_dev *
> +rte_ring_get_dev(struct rte_ring *r)
> +{
> +	struct ring_as_pktdev {
> +		RTE_PKT_DEV_HDR(rte_ring_dev);
> +		struct rte_ring_dev_data dev_data;
> +		void *ring;
> +	} *p;
> +	if (r == NULL ||
> +			(p = rte_zmalloc(NULL, sizeof(*p), 0)) == NULL)
> +		return NULL;
> +
> +	p->ring = r;
> +	p->rx_pkt_burst = dev_rx;
> +	p->tx_pkt_burst = dev_tx;
> +	p->data = &p->dev_data;
> +
> +	snprintf(p->dev_data.name, sizeof(p->dev_data.name), "%s", r->name);
> +	p->dev_data.nb_rx_queues = 1;
> +	p->dev_data.nb_tx_queues = 1;
> +	p->dev_data.rx_queues = &p->ring;
> +	p->dev_data.tx_queues = &p->ring;
> +
> +	return (void *)p;
> +}
> +
> +
>  /*
>   * change the high water mark. If *count* is 0, water marking is
>   * disabled
> diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h
> index af68888..c2f28be 100644
> --- a/lib/librte_ring/rte_ring.h
> +++ b/lib/librte_ring/rte_ring.h
> @@ -301,6 +302,10 @@ int rte_ring_init(struct rte_ring *r, const char *name, unsigned count,
>  struct rte_ring *rte_ring_create(const char *name, unsigned count,
>  				 int socket_id, unsigned flags);
> 
> +struct rte_pkt_dev;
> +
> +struct rte_pkt_dev *rte_ring_get_dev(struct rte_ring *r);
> +
>  /**
>   * Change the high water mark.
>   *
> --
> 2.1.0