Re: [dpdk-dev] [PATCH v5 1/5] eventdev/rx_adapter: add event buffer size configurability

["Naga Harish K, S V" <s.v.naga.harish.k@intel.com>]

Hi Jay,

> -----Original Message-----
> From: Jayatheerthan, Jay <jay.jayatheerthan@intel.com>
> Sent: Tuesday, October 5, 2021 12:49 PM
> To: Naga Harish K, S V <s.v.naga.harish.k@intel.com>; jerinj@marvell.com
> Cc: dev@dpdk.org; Kundapura, Ganapati <ganapati.kundapura@intel.com>
> Subject: RE: [PATCH v5 1/5] eventdev/rx_adapter: add event buffer size
> configurability
> 
> > -----Original Message-----
> > From: Naga Harish K, S V <s.v.naga.harish.k@intel.com>
> > Sent: Monday, October 4, 2021 11:11 AM
> > To: jerinj@marvell.com; Jayatheerthan, Jay
> > <jay.jayatheerthan@intel.com>
> > Cc: dev@dpdk.org; Kundapura, Ganapati <ganapati.kundapura@intel.com>
> > Subject: [PATCH v5 1/5] eventdev/rx_adapter: add event buffer size
> > configurability
> >
> > Currently event buffer is static array with a default size defined
> > internally.
> >
> > To configure event buffer size from application,
> > ``rte_event_eth_rx_adapter_create_with_params`` api is added which
> > takes ``struct rte_event_eth_rx_adapter_params`` to configure event
> > buffer size in addition other params . The event buffer size is
> > rounded up for better buffer utilization and performance . In case of
> > NULL params argument, default event buffer size is used.
> >
> > Signed-off-by: Naga Harish K S V <s.v.naga.harish.k@intel.com>
> > Signed-off-by: Ganapati Kundapura <ganapati.kundapura@intel.com>
> >
> > ---
> > v5:
> > * reverted queue conf get unit test change
> >
> > v4:
> > * rebased with latest dpdk-next-eventdev branch
> > * changed queue conf get unit test
> >
> > v3:
> > * updated documentation and code comments as per review comments.
> > * updated new create api test case name with suitable one.
> >
> > v2:
> > * Updated header file and rx adapter documentation as per review
> comments.
> > * new api name is modified as
> rte_event_eth_rx_adapter_create_with_params
> >   as per review comments.
> > * rxa_params pointer argument Value NULL is allowed to represent the
> >   default values
> >
> > v1:
> > * Initial implementation with documentation and unit tests.
> > ---
> > ---
> >  .../prog_guide/event_ethernet_rx_adapter.rst  |  7 ++
> >  lib/eventdev/rte_event_eth_rx_adapter.c       | 98 +++++++++++++++++--
> >  lib/eventdev/rte_event_eth_rx_adapter.h       | 41 +++++++-
> >  lib/eventdev/version.map                      |  2 +
> >  4 files changed, 140 insertions(+), 8 deletions(-)
> >
> > diff --git a/doc/guides/prog_guide/event_ethernet_rx_adapter.rst
> > b/doc/guides/prog_guide/event_ethernet_rx_adapter.rst
> > index ce23d8a474..8526aecf57 100644
> > --- a/doc/guides/prog_guide/event_ethernet_rx_adapter.rst
> > +++ b/doc/guides/prog_guide/event_ethernet_rx_adapter.rst
> > @@ -62,6 +62,13 @@ service function and needs to create an event port
> > for it. The callback is  expected to fill the ``struct
> > rte_event_eth_rx_adapter_conf structure``  passed to it.
> >
> > +If the application desires to control the event buffer size, it can
> > +use the ``rte_event_eth_rx_adapter_create_with_params()`` api. The
> > +event buffer size is specified using ``struct
> rte_event_eth_rx_adapter_params::event_buf_size``.
> > +The function is passed the event device to be associated with the
> > +adapter and port configuration for the adapter to setup an event port
> > +if the adapter needs to use a service function.
> > +
> >  Adding Rx Queues to the Adapter Instance
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > diff --git a/lib/eventdev/rte_event_eth_rx_adapter.c
> > b/lib/eventdev/rte_event_eth_rx_adapter.c
> > index 10491ca07b..606db241b8 100644
> > --- a/lib/eventdev/rte_event_eth_rx_adapter.c
> > +++ b/lib/eventdev/rte_event_eth_rx_adapter.c
> > @@ -85,7 +85,9 @@ struct rte_eth_event_enqueue_buffer {
> >  	/* Count of events in this buffer */
> >  	uint16_t count;
> >  	/* Array of events in this buffer */
> > -	struct rte_event events[ETH_EVENT_BUFFER_SIZE];
> > +	struct rte_event *events;
> > +	/* size of event buffer */
> > +	uint16_t events_size;
> >  	/* Event enqueue happens from head */
> >  	uint16_t head;
> >  	/* New packets from rte_eth_rx_burst is enqued from tail */ @@
> > -946,7 +948,7 @@ rxa_buffer_mbufs(struct rte_event_eth_rx_adapter
> *rx_adapter,
> >  		dropped = 0;
> >  		nb_cb = dev_info->cb_fn(eth_dev_id, rx_queue_id,
> >  				       buf->last |
> > -				       (RTE_DIM(buf->events) & ~buf-
> >last_mask),
> > +				       (buf->events_size & ~buf->last_mask),
> >  				       buf->count >= BATCH_SIZE ?
> >  						buf->count - BATCH_SIZE : 0,
> >  				       &buf->events[buf->tail],
> > @@ -972,7 +974,7 @@ rxa_pkt_buf_available(struct
> rte_eth_event_enqueue_buffer *buf)
> >  	uint32_t nb_req = buf->tail + BATCH_SIZE;
> >
> >  	if (!buf->last) {
> > -		if (nb_req <= RTE_DIM(buf->events))
> > +		if (nb_req <= buf->events_size)
> >  			return true;
> >
> >  		if (buf->head >= BATCH_SIZE) {
> > @@ -2206,12 +2208,15 @@ rxa_ctrl(uint8_t id, int start)
> >  	return 0;
> >  }
> >
> > -int
> > -rte_event_eth_rx_adapter_create_ext(uint8_t id, uint8_t dev_id,
> > -				rte_event_eth_rx_adapter_conf_cb
> conf_cb,
> > -				void *conf_arg)
> > +static int
> > +rxa_create(uint8_t id, uint8_t dev_id,
> > +	   struct rte_event_eth_rx_adapter_params *rxa_params,
> > +	   rte_event_eth_rx_adapter_conf_cb conf_cb,
> > +	   void *conf_arg)
> >  {
> >  	struct rte_event_eth_rx_adapter *rx_adapter;
> > +	struct rte_eth_event_enqueue_buffer *buf;
> > +	struct rte_event *events;
> >  	int ret;
> >  	int socket_id;
> >  	uint16_t i;
> > @@ -2226,6 +2231,7 @@ rte_event_eth_rx_adapter_create_ext(uint8_t
> id,
> > uint8_t dev_id,
> >
> >  	RTE_EVENT_ETH_RX_ADAPTER_ID_VALID_OR_ERR_RET(id, -
> EINVAL);
> >  	RTE_EVENTDEV_VALID_DEVID_OR_ERR_RET(dev_id, -EINVAL);
> > +
> >  	if (conf_cb == NULL)
> >  		return -EINVAL;
> >
> > @@ -2273,11 +2279,30 @@
> rte_event_eth_rx_adapter_create_ext(uint8_t id, uint8_t dev_id,
> >  		rte_free(rx_adapter);
> >  		return -ENOMEM;
> >  	}
> > +
> >  	rte_spinlock_init(&rx_adapter->rx_lock);
> > +
> >  	for (i = 0; i < RTE_MAX_ETHPORTS; i++)
> >  		rx_adapter->eth_devices[i].dev = &rte_eth_devices[i];
> >
> > +	/* Rx adapter event buffer allocation */
> > +	buf = &rx_adapter->event_enqueue_buffer;
> > +	buf->events_size = RTE_ALIGN(rxa_params->event_buf_size,
> > +BATCH_SIZE);
> 
> Do we need to align event_buf_size again here ? The caller seems to take
> care of it.

It is redundant, and is removed in v6 patchset.

> 
> > +
> > +	events = rte_zmalloc_socket(rx_adapter->mem_name,
> > +				    buf->events_size * sizeof(*events),
> > +				    0, socket_id);
> > +	if (events == NULL) {
> > +		RTE_EDEV_LOG_ERR("Failed to allocate mem for event
> buffer\n");
> > +		rte_free(rx_adapter->eth_devices);
> > +		rte_free(rx_adapter);
> > +		return -ENOMEM;
> > +	}
> > +
> > +	rx_adapter->event_enqueue_buffer.events = events;
> > +
> >  	event_eth_rx_adapter[id] = rx_adapter;
> > +
> >  	if (conf_cb == rxa_default_conf_cb)
> >  		rx_adapter->default_cb_arg = 1;
> >
> > @@ -2293,6 +2318,61 @@ rte_event_eth_rx_adapter_create_ext(uint8_t
> id, uint8_t dev_id,
> >  	return 0;
> >  }
> >
> > +int
> > +rte_event_eth_rx_adapter_create_ext(uint8_t id, uint8_t dev_id,
> > +				rte_event_eth_rx_adapter_conf_cb
> conf_cb,
> > +				void *conf_arg)
> > +{
> > +	struct rte_event_eth_rx_adapter_params rxa_params;
> 
> Can initialize rxa_params in case if more fields get added in future that we
> don't assign here.

Done

> 
> > +
> > +	/* use default values for adapter params */
> > +	rxa_params.event_buf_size = ETH_EVENT_BUFFER_SIZE;
> > +
> > +	return rxa_create(id, dev_id, &rxa_params, conf_cb, conf_arg); }
> > +
> > +int
> > +rte_event_eth_rx_adapter_create_with_params(uint8_t id, uint8_t
> dev_id,
> > +			struct rte_event_port_conf *port_config,
> > +			struct rte_event_eth_rx_adapter_params
> *rxa_params) {
> > +	struct rte_event_port_conf *pc;
> > +	int ret;
> > +	struct rte_event_eth_rx_adapter_params temp_params = {0};
> > +
> > +	if (port_config == NULL)
> > +		return -EINVAL;
> > +
> > +	/* use default values if rxa_parmas is NULL */
> > +	if (rxa_params == NULL) {
> > +		rxa_params = &temp_params;
> > +		rxa_params->event_buf_size = ETH_EVENT_BUFFER_SIZE;
> > +	}
> > +
> > +	if (rxa_params->event_buf_size == 0)
> > +		return -EINVAL;
> > +
> > +	pc = rte_malloc(NULL, sizeof(*pc), 0);
> > +	if (pc == NULL)
> > +		return -ENOMEM;
> > +
> > +	*pc = *port_config;
> > +
> > +	/* adjust event buff size with BATCH_SIZE used for fetching packets
> > +	 * from NIC rx queues to get full buffer utilization and prevent
> > +	 * unnecessary rollovers.
> > +	 */
> > +	rxa_params->event_buf_size = RTE_ALIGN(rxa_params-
> >event_buf_size,
> > +					       BATCH_SIZE);
> > +	rxa_params->event_buf_size += BATCH_SIZE + BATCH_SIZE;
> 
> Please add brackets to be more explicit and readable.

Done

> 
> > +
> > +	ret = rxa_create(id, dev_id, rxa_params, rxa_default_conf_cb, pc);
> > +	if (ret)
> > +		rte_free(pc);
> > +
> > +	return ret;
> > +}
> > +
> >  int
> >  rte_event_eth_rx_adapter_create(uint8_t id, uint8_t dev_id,
> >  		struct rte_event_port_conf *port_config) @@ -2302,12
> +2382,14 @@
> > rte_event_eth_rx_adapter_create(uint8_t id, uint8_t dev_id,
> >
> >  	if (port_config == NULL)
> >  		return -EINVAL;
> > +
> >  	RTE_EVENT_ETH_RX_ADAPTER_ID_VALID_OR_ERR_RET(id, -
> EINVAL);
> >
> >  	pc = rte_malloc(NULL, sizeof(*pc), 0);
> >  	if (pc == NULL)
> >  		return -ENOMEM;
> >  	*pc = *port_config;
> > +
> >  	ret = rte_event_eth_rx_adapter_create_ext(id, dev_id,
> >  					rxa_default_conf_cb,
> >  					pc);
> > @@ -2336,6 +2418,7 @@ rte_event_eth_rx_adapter_free(uint8_t id)
> >  	if (rx_adapter->default_cb_arg)
> >  		rte_free(rx_adapter->conf_arg);
> >  	rte_free(rx_adapter->eth_devices);
> > +	rte_free(rx_adapter->event_enqueue_buffer.events);
> >  	rte_free(rx_adapter);
> >  	event_eth_rx_adapter[id] = NULL;
> >
> > @@ -2711,6 +2794,7 @@ rte_event_eth_rx_adapter_stats_get(uint8_t id,
> >
> >  	stats->rx_packets += dev_stats_sum.rx_packets;
> >  	stats->rx_enq_count += dev_stats_sum.rx_enq_count;
> > +
> >  	return 0;
> >  }
> >
> > diff --git a/lib/eventdev/rte_event_eth_rx_adapter.h
> > b/lib/eventdev/rte_event_eth_rx_adapter.h
> > index 470543e434..846ca569e9 100644
> > --- a/lib/eventdev/rte_event_eth_rx_adapter.h
> > +++ b/lib/eventdev/rte_event_eth_rx_adapter.h
> > @@ -26,6 +26,7 @@
> >   * The ethernet Rx event adapter's functions are:
> >   *  - rte_event_eth_rx_adapter_create_ext()
> >   *  - rte_event_eth_rx_adapter_create()
> > + *  - rte_event_eth_rx_adapter_create_with_params()
> >   *  - rte_event_eth_rx_adapter_free()
> >   *  - rte_event_eth_rx_adapter_queue_add()
> >   *  - rte_event_eth_rx_adapter_queue_del()
> > @@ -37,7 +38,7 @@
> >   *
> >   * The application creates an ethernet to event adapter using
> >   * rte_event_eth_rx_adapter_create_ext() or
> > rte_event_eth_rx_adapter_create()
> > - * functions.
> > + * or rte_event_eth_rx_adapter_create_with_params() functions.
> >   * The adapter needs to know which ethernet rx queues to poll for mbufs
> as well
> >   * as event device parameters such as the event queue identifier, event
> >   * priority and scheduling type that the adapter should use when
> > constructing @@ -257,6 +258,17 @@ struct
> rte_event_eth_rx_adapter_vector_limits {
> >  	 */
> >  };
> >
> > +/**
> > + * A structure to hold adapter config params  */ struct
> > +rte_event_eth_rx_adapter_params {
> > +	uint16_t event_buf_size;
> > +	/**< size of event buffer for the adapter.
> > +	 * This value is rounded up for better buffer utilization
> > +	 * and performance.
> > +	 */
> > +};
> > +
> >  /**
> >   *
> >   * Callback function invoked by the SW adapter before it continues @@
> > -357,6 +369,33 @@ int rte_event_eth_rx_adapter_create_ext(uint8_t id,
> > uint8_t dev_id,  int rte_event_eth_rx_adapter_create(uint8_t id, uint8_t
> dev_id,
> >  				struct rte_event_port_conf *port_config);
> >
> > +/**
> > + * This is a variant of rte_event_eth_rx_adapter_create() with
> > +additional
> > + * adapter params specified in ``struct
> rte_event_eth_rx_adapter_params``.
> > + *
> > + * @param id
> > + *  The identifier of the ethernet Rx event adapter.
> > + *
> > + * @param dev_id
> > + *  The identifier of the event device to configure.
> > + *
> > + * @param port_config
> > + *  Argument of type *rte_event_port_conf* that is passed to the
> > +conf_cb
> > + *  function.
> > + *
> > + * @param rxa_params
> > + *  Pointer to struct rte_event_eth_rx_adapter_params.
> > + *  In case of NULL, default values are used.
> > + *
> > + * @return
> > + *   - 0: Success
> > + *   - <0: Error code on failure
> > + */
> > +__rte_experimental
> > +int rte_event_eth_rx_adapter_create_with_params(uint8_t id, uint8_t
> dev_id,
> > +			struct rte_event_port_conf *port_config,
> > +			struct rte_event_eth_rx_adapter_params
> *rxa_params);
> > +
> >  /**
> >   * Free an event adapter
> >   *
> > diff --git a/lib/eventdev/version.map b/lib/eventdev/version.map index
> > 9f280160fa..7de18497a6 100644
> > --- a/lib/eventdev/version.map
> > +++ b/lib/eventdev/version.map
> > @@ -138,6 +138,8 @@ EXPERIMENTAL {
> >  	__rte_eventdev_trace_port_setup;
> >  	# added in 20.11
> >  	rte_event_pmd_pci_probe_named;
> > +	# added in 21.11
> > +	rte_event_eth_rx_adapter_create_with_params;
> >
> >  	#added in 21.05
> >  	rte_event_vector_pool_create;
> > --
> > 2.25.1