Re: [dpdk-dev] [PATCH] eventdev: remove event copy in Rx adapter

[Jerin Jacob Kollanukkaran <jerinj@marvell.com>]

> -----Original Message-----
> From: Nikhil Rao <nikhil.rao@intel.com>
> Sent: Wednesday, May 22, 2019 3:23 AM
> To: Jerin Jacob Kollanukkaran <jerinj@marvell.com>;
> mattias.ronnblom@ericsson.com
> Cc: dev@dpdk.org; Nikhil Rao <nikhil.rao@intel.com>
> Subject: [PATCH] eventdev: remove event copy in Rx adapter
> 
> Remove copy from temporary event array on the stack to the enqueue
> buffer event array entry, instead initialize event in the enqueue buffer event
> array entry.
> 
> Suggested-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
> Signed-off-by: Nikhil Rao <nikhil.rao@intel.com>
> ---
> 
> Hi Mattias,
> 
> This patch eliminates the event copy as you previously mentioned
> (https://patches.dpdk.org/patch/53350/), the enqueue buffer array is still
> retained in the rx_adapter struct, since the Rx adapter service function can
> return with events in the enqueue buffer that have not yet been shipped to
> the event device.
> 
> Let me know your comments.
 
Mattias,

Let us know, if you have any comments on this patch?



> Thanks,
> Nikhil
> 
>  lib/librte_eventdev/rte_event_eth_rx_adapter.c | 20 ++++----------------
>  1 file changed, 4 insertions(+), 16 deletions(-)
> 
> diff --git a/lib/librte_eventdev/rte_event_eth_rx_adapter.c
> b/lib/librte_eventdev/rte_event_eth_rx_adapter.c
> index 8d178be..a201668 100644
> --- a/lib/librte_eventdev/rte_event_eth_rx_adapter.c
> +++ b/lib/librte_eventdev/rte_event_eth_rx_adapter.c
> @@ -715,18 +715,6 @@ static uint16_t rxa_gcd_u16(uint16_t a, uint16_t b)
>  	}
>  }
> 
> -/* Add event to buffer, free space check is done prior to calling
> - * this function
> - */
> -static inline void
> -rxa_buffer_event(struct rte_event_eth_rx_adapter *rx_adapter,
> -		struct rte_event *ev)
> -{
> -	struct rte_eth_event_enqueue_buffer *buf =
> -	    &rx_adapter->event_enqueue_buffer;
> -	rte_memcpy(&buf->events[buf->count++], ev, sizeof(struct
> rte_event));
> -}
> -
>  /* Enqueue buffered events to event device */  static inline uint16_t
> rxa_flush_event_buffer(struct rte_event_eth_rx_adapter *rx_adapter)
> @@ -769,11 +757,11 @@ static uint16_t rxa_gcd_u16(uint16_t a, uint16_t b)
>  					&dev_info-
> >rx_queue[rx_queue_id];
>  	struct rte_eth_event_enqueue_buffer *buf =
>  					&rx_adapter-
> >event_enqueue_buffer;
> +	struct rte_event *ev = &buf->events[buf->count];
>  	int32_t qid = eth_rx_queue_info->event_queue_id;
>  	uint8_t sched_type = eth_rx_queue_info->sched_type;
>  	uint8_t priority = eth_rx_queue_info->priority;
>  	uint32_t flow_id;
> -	struct rte_event events[BATCH_SIZE];
>  	struct rte_mbuf *m = mbufs[0];
>  	uint32_t rss_mask;
>  	uint32_t rss;
> @@ -811,7 +799,6 @@ static uint16_t rxa_gcd_u16(uint16_t a, uint16_t b)
> 
>  	for (i = 0; i < num; i++) {
>  		m = mbufs[i];
> -		struct rte_event *ev = &events[i];
> 
>  		rss = do_rss ?
>  			rxa_do_softrss(m, rx_adapter->rss_key_be) :
> @@ -828,9 +815,10 @@ static uint16_t rxa_gcd_u16(uint16_t a, uint16_t b)
>  		ev->sub_event_type = 0;
>  		ev->priority = priority;
>  		ev->mbuf = m;
> -
> -		rxa_buffer_event(rx_adapter, ev);
> +		ev++;
>  	}
> +
> +	buf->count += num;
>  }
> 
>  /* Enqueue packets from  <port, q>  to event buffer */
> --
> 1.8.3.1