Re: [dpdk-dev] [PATCH 1/2] eventdev: add implicit release disable capability

["Van Haaren, Harry" <harry.van.haaren@intel.com>]

> -----Original Message-----
> From: Eads, Gage
> Sent: Thursday, November 30, 2017 4:21 AM
> To: dev@dpdk.org
> Cc: jerin.jacob@caviumnetworks.com; Van Haaren, Harry
> <harry.van.haaren@intel.com>; Richardson, Bruce
> <bruce.richardson@intel.com>; hemant.agrawal@nxp.com; nipun.gupta@nxp.com;
> santosh.shukla@caviumnetworks.com
> Subject: [PATCH 1/2] eventdev: add implicit release disable capability
> 
> This commit introduces a capability for disabling the "implicit" release
> functionality for a port, which prevents the eventdev PMD from issuing
> outstanding releases for previously dequeued events when dequeuing a new
> batch of events.
> 
> If a PMD does not support this capability, the application will receive an
> error if it attempts to setup a port with implicit releases disabled.
> Otherwise, if the port is configured with implicit releases disabled, the
> application must release each dequeued event by invoking
> rte_event_enqueue_burst() with RTE_EVENT_OP_RELEASE or
> RTE_EVENT_OP_FORWARD.
> 
> Signed-off-by: Gage Eads <gage.eads@intel.com>

Some comments inline. In general, I think this makes sense, and is the easiest solution that I can see.


>  drivers/event/dpaa2/dpaa2_eventdev.c       |  2 ++
>  drivers/event/octeontx/ssovf_evdev.c       |  1 +
>  drivers/event/skeleton/skeleton_eventdev.c |  1 +
>  drivers/event/sw/sw_evdev.c                | 10 +++++++---
>  drivers/event/sw/sw_evdev.h                |  1 +
>  drivers/event/sw/sw_evdev_worker.c         | 16 ++++++++--------
>  examples/eventdev_pipeline_sw_pmd/main.c   | 24 +++++++++++++++++++++++-
>  lib/librte_eventdev/rte_eventdev.c         |  9 +++++++++
>  lib/librte_eventdev/rte_eventdev.h         | 23 ++++++++++++++++++++---
>  test/test/test_eventdev.c                  |  9 +++++++++
>  test/test/test_eventdev_sw.c               | 20 ++++++++++++++++++--
>  11 files changed, 99 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/event/dpaa2/dpaa2_eventdev.c
> b/drivers/event/dpaa2/dpaa2_eventdev.c
> index eeeb231..236b211 100644
> --- a/drivers/event/dpaa2/dpaa2_eventdev.c
> +++ b/drivers/event/dpaa2/dpaa2_eventdev.c
> @@ -440,6 +440,8 @@ dpaa2_eventdev_port_def_conf(struct rte_eventdev *dev,
> uint8_t port_id,
>  		DPAA2_EVENT_MAX_PORT_DEQUEUE_DEPTH;
>  	port_conf->enqueue_depth =
>  		DPAA2_EVENT_MAX_PORT_ENQUEUE_DEPTH;
> +	port_conf->disable_implicit_release =
> +		0;

Merge "0;" onto previous line?

<snip>

> --- a/drivers/event/skeleton/skeleton_eventdev.c
> +++ b/drivers/event/skeleton/skeleton_eventdev.c
> @@ -237,6 +237,7 @@ skeleton_eventdev_port_def_conf(struct rte_eventdev
> *dev, uint8_t port_id,
>  	port_conf->new_event_threshold = 32 * 1024;
>  	port_conf->dequeue_depth = 16;
>  	port_conf->enqueue_depth = 16;
> +	port_conf->disable_implicit_release = false;

Prefer 0 to false.

<snip>

> diff --git a/examples/eventdev_pipeline_sw_pmd/main.c
> b/examples/eventdev_pipeline_sw_pmd/main.c
> index 5f431d8..3910b53 100644
> --- a/examples/eventdev_pipeline_sw_pmd/main.c
> +++ b/examples/eventdev_pipeline_sw_pmd/main.c
> @@ -62,6 +62,7 @@ struct prod_data {
>  struct cons_data {
>  	uint8_t dev_id;
>  	uint8_t port_id;
> +	bool release;

I'd personally uint8_t this instead of bool, which requires <stdbool.h>. I haven't seen stdbool.h in other DPDK headers, so suggesting stick with the good old byte-sized integers for flags.. 


>  } __rte_cache_aligned;
> 
>  static struct prod_data prod_data;
> @@ -167,6 +168,18 @@ consumer(void)
>  		uint8_t outport = packets[i].mbuf->port;
>  		rte_eth_tx_buffer(outport, 0, fdata->tx_buf[outport],
>  				packets[i].mbuf);
> +
> +		packets[i].op = RTE_EVENT_OP_RELEASE;
> +	}
> +
> +	if (cons_data.release) {
> +		uint16_t nb_tx;
> +
> +		nb_tx = rte_event_enqueue_burst(dev_id, port_id, packets, n);
> +		while (nb_tx < n)
> +			nb_tx += rte_event_enqueue_burst(dev_id, port_id,
> +							 packets + nb_tx,
> +							 n - nb_tx);
>  	}
> 
>  	/* Print out mpps every 1<22 packets */
> @@ -702,6 +715,7 @@ setup_eventdev(struct prod_data *prod_data,
>  	};
> 
>  	struct port_link worker_queues[MAX_NUM_STAGES];
> +	bool disable_implicit_release;

Same uint8_t over stdbool.h comment as above


> @@ -3240,7 +3244,7 @@ test_sw_eventdev(void)
>  	if (rte_lcore_count() >= 3) {
>  		printf("*** Running Worker loopback test...\n");
> -		ret = worker_loopback(t);
> +		ret = worker_loopback(t, 0);
>  		if (ret != 0) {
>  			printf("ERROR - Worker loopback test FAILED.\n");
>  			return ret;
> @@ -3249,6 +3253,18 @@ test_sw_eventdev(void)
>  		printf("### Not enough cores for worker loopback test.\n");
>  		printf("### Need at least 3 cores for test.\n");
>  	}
> +	if (rte_lcore_count() >= 3) {
> +		printf("*** Running Worker loopback test (implicit release
> disabled)...\n");
> +		ret = worker_loopback(t, 1);
> +		if (ret != 0) {
> +			printf("ERROR - Worker loopback test FAILED.\n");
> +			return ret;
> +		}
> +	} else {
> +		printf("### Not enough cores for worker loopback test.\n");
> +		printf("### Need at least 3 cores for test.\n");
> +	}

The double if (count >= 3) here looks like it could be removed and the loopback(t, 1) added to the first if()- but otherwise the logic is fine.


With the above changes, this looks good to me!

Acked-by: Harry van Haaren <harry.van.haaren@intel.com>