[v2,18/22] event/dlb2: add PMD's token pop public interface

Message ID 1602958879-8558-19-git-send-email-timothy.mcdaniel@intel.com (mailing list archive)
State Superseded, archived
Delegated to: Jerin Jacob
Headers
Series Add DLB2 PMD |

Checks

Context Check Description
ci/checkpatch success coding style OK

Commit Message

Timothy McDaniel Oct. 17, 2020, 6:21 p.m. UTC
  The PMD uses a public interface to allow applications to
control the token pop mode. Supported token pop modes are
as follows, and they impact core scheduling affinity for
ldb ports.

AUTO_POP: Pop the CQ tokens immediately after dequeueing.
DELAYED_POP: Pop CQ tokens after (dequeue_depth - 1) events
             are released. Supported on load-balanced ports
             only.
DEFERRED_POP: Pop the CQ tokens during next dequeue operation.

Signed-off-by: Timothy McDaniel <timothy.mcdaniel@intel.com>
---
 doc/api/doxy-api-index.md                         |  1 +
 drivers/event/dlb2/dlb2.c                         | 53 ++++++++++++++++--
 drivers/event/dlb2/dlb2_priv.h                    |  3 +
 drivers/event/dlb2/meson.build                    |  5 +-
 drivers/event/dlb2/rte_pmd_dlb2.c                 | 39 +++++++++++++
 drivers/event/dlb2/rte_pmd_dlb2.h                 | 68 +++++++++++++++++++++++
 drivers/event/dlb2/rte_pmd_dlb2_event_version.map |  6 ++
 7 files changed, 168 insertions(+), 7 deletions(-)
 create mode 100644 drivers/event/dlb2/rte_pmd_dlb2.c
 create mode 100644 drivers/event/dlb2/rte_pmd_dlb2.h
  

Comments

Jerin Jacob Oct. 18, 2020, 9:13 a.m. UTC | #1
On Sat, Oct 17, 2020 at 11:57 PM Timothy McDaniel
<timothy.mcdaniel@intel.com> wrote:
>
> The PMD uses a public interface to allow applications to
> control the token pop mode. Supported token pop modes are
> as follows, and they impact core scheduling affinity for
> ldb ports.
>
> AUTO_POP: Pop the CQ tokens immediately after dequeueing.
> DELAYED_POP: Pop CQ tokens after (dequeue_depth - 1) events
>              are released. Supported on load-balanced ports
>              only.
> DEFERRED_POP: Pop the CQ tokens during next dequeue operation.
>
> Signed-off-by: Timothy McDaniel <timothy.mcdaniel@intel.com>
> ---
>  doc/api/doxy-api-index.md                         |  1 +
>  drivers/event/dlb2/dlb2.c                         | 53 ++++++++++++++++--
>  drivers/event/dlb2/dlb2_priv.h                    |  3 +
>  drivers/event/dlb2/meson.build                    |  5 +-
>  drivers/event/dlb2/rte_pmd_dlb2.c                 | 39 +++++++++++++
>  drivers/event/dlb2/rte_pmd_dlb2.h                 | 68 +++++++++++++++++++++++
>  drivers/event/dlb2/rte_pmd_dlb2_event_version.map |  6 ++
>  7 files changed, 168 insertions(+), 7 deletions(-)
>  create mode 100644 drivers/event/dlb2/rte_pmd_dlb2.c
>  create mode 100644 drivers/event/dlb2/rte_pmd_dlb2.h
>
> diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
> index b855a8f..2b2020c 100644
> --- a/doc/api/doxy-api-index.md
> +++ b/doc/api/doxy-api-index.md
> @@ -26,6 +26,7 @@ The public API headers are grouped by topics:
>    [event_eth_tx_adapter]   (@ref rte_event_eth_tx_adapter.h),
>    [event_timer_adapter]    (@ref rte_event_timer_adapter.h),
>    [event_crypto_adapter]   (@ref rte_event_crypto_adapter.h),
> +  [dlb2]              (@ref rte_pmd_dlb2.h)

move this under the already existing "- **device specific**:" section.
  
Ray Kinsella Oct. 19, 2020, 10:01 a.m. UTC | #2
On 17/10/2020 19:21, Timothy McDaniel wrote:
> The PMD uses a public interface to allow applications to
> control the token pop mode. Supported token pop modes are
> as follows, and they impact core scheduling affinity for
> ldb ports.
> 
> AUTO_POP: Pop the CQ tokens immediately after dequeueing.
> DELAYED_POP: Pop CQ tokens after (dequeue_depth - 1) events
>              are released. Supported on load-balanced ports
>              only.
> DEFERRED_POP: Pop the CQ tokens during next dequeue operation.
> 
> Signed-off-by: Timothy McDaniel <timothy.mcdaniel@intel.com>
> ---
>  doc/api/doxy-api-index.md                         |  1 +
>  drivers/event/dlb2/dlb2.c                         | 53 ++++++++++++++++--
>  drivers/event/dlb2/dlb2_priv.h                    |  3 +
>  drivers/event/dlb2/meson.build                    |  5 +-
>  drivers/event/dlb2/rte_pmd_dlb2.c                 | 39 +++++++++++++
>  drivers/event/dlb2/rte_pmd_dlb2.h                 | 68 +++++++++++++++++++++++
>  drivers/event/dlb2/rte_pmd_dlb2_event_version.map |  6 ++
>  7 files changed, 168 insertions(+), 7 deletions(-)
>  create mode 100644 drivers/event/dlb2/rte_pmd_dlb2.c
>  create mode 100644 drivers/event/dlb2/rte_pmd_dlb2.h
> 
> diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
> index b855a8f..2b2020c 100644
> --- a/doc/api/doxy-api-index.md
> +++ b/doc/api/doxy-api-index.md
> @@ -26,6 +26,7 @@ The public API headers are grouped by topics:
>    [event_eth_tx_adapter]   (@ref rte_event_eth_tx_adapter.h),
>    [event_timer_adapter]    (@ref rte_event_timer_adapter.h),
>    [event_crypto_adapter]   (@ref rte_event_crypto_adapter.h),
> +  [dlb2]	       (@ref rte_pmd_dlb2.h)
>    [rawdev]             (@ref rte_rawdev.h),
>    [metrics]            (@ref rte_metrics.h),
>    [bitrate]            (@ref rte_bitrate.h),
> diff --git a/drivers/event/dlb2/dlb2.c b/drivers/event/dlb2/dlb2.c
> index 483659e..9a41418 100644
> --- a/drivers/event/dlb2/dlb2.c
> +++ b/drivers/event/dlb2/dlb2.c
> @@ -1200,7 +1200,7 @@ dlb2_hw_create_ldb_port(struct dlb2_eventdev *dlb2,
>  	qm_port->qid_mappings = &dlb2->qm_ldb_to_ev_queue_id[0];
>  
>  	qm_port->dequeue_depth = dequeue_depth;
> -
> +	qm_port->token_pop_thresh = dequeue_depth;
>  	qm_port->owed_tokens = 0;
>  	qm_port->issued_releases = 0;
>  
> @@ -1368,6 +1368,8 @@ dlb2_hw_create_dir_port(struct dlb2_eventdev *dlb2,
>  
>  	qm_port->dequeue_depth = dequeue_depth;
>  
> +	/* Directed ports are auto-pop, by default. */
> +	qm_port->token_pop_mode = AUTO_POP;
>  	qm_port->owed_tokens = 0;
>  	qm_port->issued_releases = 0;
>  
> @@ -2615,6 +2617,14 @@ dlb2_event_enqueue_burst(void *event_port,
>  		dlb2_event_build_hcws(qm_port, &events[i], j,
>  				      sched_types, queue_ids);
>  
> +		if (qm_port->token_pop_mode == DELAYED_POP && j < 4 &&
> +		    qm_port->issued_releases >= qm_port->token_pop_thresh - 1) {
> +			dlb2_construct_token_pop_qe(qm_port, j);
> +
> +			/* Reset the releases counter for the next QE batch */
> +			qm_port->issued_releases -= qm_port->token_pop_thresh;
> +		}
> +
>  		dlb2_hw_do_enqueue(qm_port, i == 0, port_data);
>  
>  		cnt += j;
> @@ -2623,6 +2633,11 @@ dlb2_event_enqueue_burst(void *event_port,
>  			break;
>  	}
>  
> +	if (qm_port->token_pop_mode == DELAYED_POP &&
> +	    qm_port->issued_releases >= qm_port->token_pop_thresh - 1) {
> +		dlb2_consume_qe_immediate(qm_port, qm_port->owed_tokens);
> +		qm_port->issued_releases -= qm_port->token_pop_thresh;
> +	}
>  	return cnt;
>  }
>  
> @@ -3105,11 +3120,25 @@ dlb2_event_release(struct dlb2_eventdev *dlb2,
>  		if (j == 0)
>  			break;
>  
> +		if (qm_port->token_pop_mode == DELAYED_POP && j < 4 &&
> +		    qm_port->issued_releases >= qm_port->token_pop_thresh - 1) {
> +			dlb2_construct_token_pop_qe(qm_port, j);
> +
> +			/* Reset the releases counter for the next QE batch */
> +			qm_port->issued_releases -= qm_port->token_pop_thresh;
> +		}
> +
>  		dlb2_hw_do_enqueue(qm_port, i == 0, port_data);
>  
>  		cnt += j;
>  	}
>  
> +	if (qm_port->token_pop_mode == DELAYED_POP &&
> +	    qm_port->issued_releases >= qm_port->token_pop_thresh - 1) {
> +		dlb2_consume_qe_immediate(qm_port, qm_port->owed_tokens);
> +		qm_port->issued_releases -= qm_port->token_pop_thresh;
> +	}
> +
>  sw_credit_update:
>  	/* each release returns one credit */
>  	if (!ev_port->outstanding_releases) {
> @@ -3193,8 +3222,8 @@ dlb2_hw_dequeue_sparse(struct dlb2_eventdev *dlb2,
>  	qm_port->owed_tokens += num;
>  
>  	if (num) {
> -
> -		dlb2_consume_qe_immediate(qm_port, num);
> +		if (qm_port->token_pop_mode == AUTO_POP)
> +			dlb2_consume_qe_immediate(qm_port, num);
>  
>  		ev_port->outstanding_releases += num;
>  
> @@ -3320,8 +3349,8 @@ dlb2_hw_dequeue(struct dlb2_eventdev *dlb2,
>  	qm_port->owed_tokens += num;
>  
>  	if (num) {
> -
> -		dlb2_consume_qe_immediate(qm_port, num);
> +		if (qm_port->token_pop_mode == AUTO_POP)
> +			dlb2_consume_qe_immediate(qm_port, num);
>  
>  		ev_port->outstanding_releases += num;
>  
> @@ -3336,6 +3365,7 @@ dlb2_event_dequeue_burst(void *event_port, struct rte_event *ev, uint16_t num,
>  			 uint64_t wait)
>  {
>  	struct dlb2_eventdev_port *ev_port = event_port;
> +	struct dlb2_port *qm_port = &ev_port->qm_port;
>  	struct dlb2_eventdev *dlb2 = ev_port->dlb2;
>  	uint16_t cnt;
>  
> @@ -3351,6 +3381,9 @@ dlb2_event_dequeue_burst(void *event_port, struct rte_event *ev, uint16_t num,
>  		DLB2_INC_STAT(ev_port->stats.tx_implicit_rel, out_rels);
>  	}
>  
> +	if (qm_port->token_pop_mode == DEFERRED_POP && qm_port->owed_tokens)
> +		dlb2_consume_qe_immediate(qm_port, qm_port->owed_tokens);
> +
>  	cnt = dlb2_hw_dequeue(dlb2, ev_port, ev, num, wait);
>  
>  	DLB2_INC_STAT(ev_port->stats.traffic.total_polls, 1);
> @@ -3370,6 +3403,7 @@ dlb2_event_dequeue_burst_sparse(void *event_port, struct rte_event *ev,
>  				uint16_t num, uint64_t wait)
>  {
>  	struct dlb2_eventdev_port *ev_port = event_port;
> +	struct dlb2_port *qm_port = &ev_port->qm_port;
>  	struct dlb2_eventdev *dlb2 = ev_port->dlb2;
>  	uint16_t cnt;
>  
> @@ -3385,6 +3419,9 @@ dlb2_event_dequeue_burst_sparse(void *event_port, struct rte_event *ev,
>  		DLB2_INC_STAT(ev_port->stats.tx_implicit_rel, out_rels);
>  	}
>  
> +	if (qm_port->token_pop_mode == DEFERRED_POP && qm_port->owed_tokens)
> +		dlb2_consume_qe_immediate(qm_port, qm_port->owed_tokens);
> +
>  	cnt = dlb2_hw_dequeue_sparse(dlb2, ev_port, ev, num, wait);
>  
>  	DLB2_INC_STAT(ev_port->stats.traffic.total_polls, 1);
> @@ -3689,7 +3726,7 @@ dlb2_primary_eventdev_probe(struct rte_eventdev *dev,
>  			    struct dlb2_devargs *dlb2_args)
>  {
>  	struct dlb2_eventdev *dlb2;
> -	int err;
> +	int err, i;
>  
>  	dlb2 = dev->data->dev_private;
>  
> @@ -3739,6 +3776,10 @@ dlb2_primary_eventdev_probe(struct rte_eventdev *dev,
>  		return err;
>  	}
>  
> +	/* Initialize each port's token pop mode */
> +	for (i = 0; i < DLB2_MAX_NUM_PORTS; i++)
> +		dlb2->ev_ports[i].qm_port.token_pop_mode = AUTO_POP;
> +
>  	rte_spinlock_init(&dlb2->qm_instance.resource_lock);
>  
>  	dlb2_iface_low_level_io_init();
> diff --git a/drivers/event/dlb2/dlb2_priv.h b/drivers/event/dlb2/dlb2_priv.h
> index 61567a6..b73cf3f 100644
> --- a/drivers/event/dlb2/dlb2_priv.h
> +++ b/drivers/event/dlb2/dlb2_priv.h
> @@ -12,6 +12,7 @@
>  #include <rte_config.h>
>  #include "dlb2_user.h"
>  #include "dlb2_log.h"
> +#include "rte_pmd_dlb2.h"
>  
>  #ifndef RTE_LIBRTE_PMD_DLB2_QUELL_STATS
>  #define DLB2_INC_STAT(_stat, _incr_val) ((_stat) += _incr_val)
> @@ -290,6 +291,7 @@ struct dlb2_port {
>  	bool gen_bit;
>  	uint16_t dir_credits;
>  	uint32_t dequeue_depth;
> +	enum dlb2_token_pop_mode token_pop_mode;
>  	union dlb2_port_config cfg;
>  	uint32_t *credit_pool[DLB2_NUM_QUEUE_TYPES]; /* use __atomic builtins */
>  	uint16_t cached_ldb_credits;
> @@ -298,6 +300,7 @@ struct dlb2_port {
>  	bool int_armed;
>  	uint16_t owed_tokens;
>  	int16_t issued_releases;
> +	int16_t token_pop_thresh;
>  	int cq_depth;
>  	uint16_t cq_idx;
>  	uint16_t cq_idx_unmasked;
> diff --git a/drivers/event/dlb2/meson.build b/drivers/event/dlb2/meson.build
> index 6bf8adf..539773c 100644
> --- a/drivers/event/dlb2/meson.build
> +++ b/drivers/event/dlb2/meson.build
> @@ -1,3 +1,4 @@
> +
>  # SPDX-License-Identifier: BSD-3-Clause
>  # Copyright(c) 2019-2020 Intel Corporation
>  
> @@ -6,7 +7,9 @@ sources = files('dlb2.c',
>  		'dlb2_xstats.c',
>  		'pf/dlb2_main.c',
>  		'pf/dlb2_pf.c',
> -		'pf/base/dlb2_resource.c'
> +		'pf/base/dlb2_resource.c',
> +		'rte_pmd_dlb2.c'
>  )
>  
>  deps += ['mbuf', 'mempool', 'ring', 'pci', 'bus_pci']
> +install_headers('rte_pmd_dlb2.h')
> diff --git a/drivers/event/dlb2/rte_pmd_dlb2.c b/drivers/event/dlb2/rte_pmd_dlb2.c
> new file mode 100644
> index 0000000..b09b585
> --- /dev/null
> +++ b/drivers/event/dlb2/rte_pmd_dlb2.c
> @@ -0,0 +1,39 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2020 Intel Corporation
> + */
> +
> +#include <rte_eventdev.h>
> +#include <rte_eventdev_pmd.h>
> +
> +#include "rte_pmd_dlb2.h"
> +#include "dlb2_priv.h"
> +#include "dlb2_inline_fns.h"
> +
> +int
> +rte_pmd_dlb2_set_token_pop_mode(uint8_t dev_id,
> +				uint8_t port_id,
> +				enum dlb2_token_pop_mode mode)
> +{
> +	struct dlb2_eventdev *dlb2;
> +	struct rte_eventdev *dev;
> +
> +	RTE_EVENTDEV_VALID_DEVID_OR_ERR_RET(dev_id, -EINVAL);
> +	dev = &rte_eventdevs[dev_id];
> +
> +	dlb2 = dlb2_pmd_priv(dev);
> +
> +	if (mode >= NUM_TOKEN_POP_MODES)
> +		return -EINVAL;
> +
> +	/* The event device must be configured, but not yet started */
> +	if (!dlb2->configured || dlb2->run_state != DLB2_RUN_STATE_STOPPED)
> +		return -EINVAL;
> +
> +	/* The token pop mode must be set before configuring the port */
> +	if (port_id >= dlb2->num_ports || dlb2->ev_ports[port_id].setup_done)
> +		return -EINVAL;
> +
> +	dlb2->ev_ports[port_id].qm_port.token_pop_mode = mode;
> +
> +	return 0;
> +}
> diff --git a/drivers/event/dlb2/rte_pmd_dlb2.h b/drivers/event/dlb2/rte_pmd_dlb2.h
> new file mode 100644
> index 0000000..489693f
> --- /dev/null
> +++ b/drivers/event/dlb2/rte_pmd_dlb2.h
> @@ -0,0 +1,68 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright(c) 2020 Intel Corporation
> + */
> +
> +/*!
> + *  @file      rte_pmd_dlb2.h
> + *
> + *  @brief     DLB PMD-specific functions
> + *
> + *  @b EXPERIMENTAL: this API may change, or be removed, without prior notice
> + */
> +
> +#ifndef _RTE_PMD_DLB2_H_
> +#define _RTE_PMD_DLB2_H_
> +
> +#ifdef __cplusplus
> +extern "C" {
> +#endif
> +
> +#include <stdint.h>
> +
> +/**
> + * Selects the token pop mode for a DLB2 port.
> + */
> +enum dlb2_token_pop_mode {
> +	/* Pop the CQ tokens immediately after dequeueing. */
> +	AUTO_POP,
> +	/* Pop CQ tokens after (dequeue_depth - 1) events are released.
> +	 * Supported on load-balanced ports only.
> +	 */
> +	DELAYED_POP,
> +	/* Pop the CQ tokens during next dequeue operation. */
> +	DEFERRED_POP,
> +
> +	/* NUM_TOKEN_POP_MODES must be last */
> +	NUM_TOKEN_POP_MODES
> +};
> +


Missing the banner.

+ * @warning
+ * @b EXPERIMENTAL: this API may change, or be removed, without prior notice

> +/*!
> + * Configure the token pop mode for a DLB2 port. By default, all ports use
> + * AUTO_POP. This function must be called before calling rte_event_port_setup()
> + * for the port, but after calling rte_event_dev_configure().
> + *
> + * @param dev_id
> + *    The identifier of the event device.
> + * @param port_id
> + *    The identifier of the event port.
> + * @param mode
> + *    The token pop mode.
> + *
> + * @return
> + * - 0: Success
> + * - EINVAL: Invalid dev_id, port_id, or mode
> + * - EINVAL: The DLB2 is not configured, is already running, or the port is
> + *   already setup
> + */
> +
> +__rte_experimental
> +int
> +rte_pmd_dlb2_set_token_pop_mode(uint8_t dev_id,
> +				uint8_t port_id,
> +				enum dlb2_token_pop_mode mode);
> +
> +#ifdef __cplusplus
> +}
> +#endif
> +
> +#endif /* _RTE_PMD_DLB2_H_ */
> diff --git a/drivers/event/dlb2/rte_pmd_dlb2_event_version.map b/drivers/event/dlb2/rte_pmd_dlb2_event_version.map
> index 299ae63..84b81a4 100644
> --- a/drivers/event/dlb2/rte_pmd_dlb2_event_version.map
> +++ b/drivers/event/dlb2/rte_pmd_dlb2_event_version.map
> @@ -1,3 +1,9 @@
>  DPDK_21.0 {
>  	local: *;
>  };
> +
> +EXPERIMENTAL {
> +	global:
> +
> +	rte_pmd_dlb2_set_token_pop_mode;
> +};
>
  
Eads, Gage Oct. 20, 2020, 2:05 p.m. UTC | #3
> -----Original Message-----
> From: McDaniel, Timothy <timothy.mcdaniel@intel.com>
> Sent: Saturday, October 17, 2020 1:21 PM
> To: Mcnamara, John <john.mcnamara@intel.com>; Kovacevic, Marko
> <marko.kovacevic@intel.com>; Ray Kinsella <mdr@ashroe.eu>; Neil Horman
> <nhorman@tuxdriver.com>
> Cc: dev@dpdk.org; Carrillo, Erik G <erik.g.carrillo@intel.com>; Eads, Gage
> <gage.eads@intel.com>; Van Haaren, Harry <harry.van.haaren@intel.com>;
> jerinj@marvell.com
> Subject: [PATCH v2 18/22] event/dlb2: add PMD's token pop public interface
> 
> The PMD uses a public interface to allow applications to
> control the token pop mode. Supported token pop modes are
> as follows, and they impact core scheduling affinity for
> ldb ports.
> 
> AUTO_POP: Pop the CQ tokens immediately after dequeueing.
> DELAYED_POP: Pop CQ tokens after (dequeue_depth - 1) events
>              are released. Supported on load-balanced ports
>              only.
> DEFERRED_POP: Pop the CQ tokens during next dequeue operation.
> 
> Signed-off-by: Timothy McDaniel <timothy.mcdaniel@intel.com>

With Jerin and Ray's issues addressed:
Reviewed-by: Gage Eads <gage.eads@intel.com>

Thanks,
Gage
  
Timothy McDaniel Oct. 20, 2020, 2:12 p.m. UTC | #4
> -----Original Message-----
> From: Jerin Jacob <jerinjacobk@gmail.com>
> Sent: Sunday, October 18, 2020 4:14 AM
> To: McDaniel, Timothy <timothy.mcdaniel@intel.com>
> Cc: Mcnamara, John <john.mcnamara@intel.com>; Kovacevic, Marko
> <Marko.Kovacevic@intel.com>; Ray Kinsella <mdr@ashroe.eu>; Neil Horman
> <nhorman@tuxdriver.com>; dpdk-dev <dev@dpdk.org>; Carrillo, Erik G
> <Erik.G.Carrillo@intel.com>; Eads, Gage <gage.eads@intel.com>; Van Haaren,
> Harry <harry.van.haaren@intel.com>; Jerin Jacob <jerinj@marvell.com>
> Subject: Re: [dpdk-dev] [PATCH v2 18/22] event/dlb2: add PMD's token pop
> public interface
> 
> On Sat, Oct 17, 2020 at 11:57 PM Timothy McDaniel
> <timothy.mcdaniel@intel.com> wrote:
> >
> > The PMD uses a public interface to allow applications to
> > control the token pop mode. Supported token pop modes are
> > as follows, and they impact core scheduling affinity for
> > ldb ports.
> >
> > AUTO_POP: Pop the CQ tokens immediately after dequeueing.
> > DELAYED_POP: Pop CQ tokens after (dequeue_depth - 1) events
> >              are released. Supported on load-balanced ports
> >              only.
> > DEFERRED_POP: Pop the CQ tokens during next dequeue operation.
> >
> > Signed-off-by: Timothy McDaniel <timothy.mcdaniel@intel.com>
> > ---
> >  doc/api/doxy-api-index.md                         |  1 +
> >  drivers/event/dlb2/dlb2.c                         | 53 ++++++++++++++++--
> >  drivers/event/dlb2/dlb2_priv.h                    |  3 +
> >  drivers/event/dlb2/meson.build                    |  5 +-
> >  drivers/event/dlb2/rte_pmd_dlb2.c                 | 39 +++++++++++++
> >  drivers/event/dlb2/rte_pmd_dlb2.h                 | 68 +++++++++++++++++++++++
> >  drivers/event/dlb2/rte_pmd_dlb2_event_version.map |  6 ++
> >  7 files changed, 168 insertions(+), 7 deletions(-)
> >  create mode 100644 drivers/event/dlb2/rte_pmd_dlb2.c
> >  create mode 100644 drivers/event/dlb2/rte_pmd_dlb2.h
> >
> > diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
> > index b855a8f..2b2020c 100644
> > --- a/doc/api/doxy-api-index.md
> > +++ b/doc/api/doxy-api-index.md
> > @@ -26,6 +26,7 @@ The public API headers are grouped by topics:
> >    [event_eth_tx_adapter]   (@ref rte_event_eth_tx_adapter.h),
> >    [event_timer_adapter]    (@ref rte_event_timer_adapter.h),
> >    [event_crypto_adapter]   (@ref rte_event_crypto_adapter.h),
> > +  [dlb2]              (@ref rte_pmd_dlb2.h)
> 
> move this under the already existing "- **device specific**:" section.

okay, will do.
  

Patch

diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
index b855a8f..2b2020c 100644
--- a/doc/api/doxy-api-index.md
+++ b/doc/api/doxy-api-index.md
@@ -26,6 +26,7 @@  The public API headers are grouped by topics:
   [event_eth_tx_adapter]   (@ref rte_event_eth_tx_adapter.h),
   [event_timer_adapter]    (@ref rte_event_timer_adapter.h),
   [event_crypto_adapter]   (@ref rte_event_crypto_adapter.h),
+  [dlb2]	       (@ref rte_pmd_dlb2.h)
   [rawdev]             (@ref rte_rawdev.h),
   [metrics]            (@ref rte_metrics.h),
   [bitrate]            (@ref rte_bitrate.h),
diff --git a/drivers/event/dlb2/dlb2.c b/drivers/event/dlb2/dlb2.c
index 483659e..9a41418 100644
--- a/drivers/event/dlb2/dlb2.c
+++ b/drivers/event/dlb2/dlb2.c
@@ -1200,7 +1200,7 @@  dlb2_hw_create_ldb_port(struct dlb2_eventdev *dlb2,
 	qm_port->qid_mappings = &dlb2->qm_ldb_to_ev_queue_id[0];
 
 	qm_port->dequeue_depth = dequeue_depth;
-
+	qm_port->token_pop_thresh = dequeue_depth;
 	qm_port->owed_tokens = 0;
 	qm_port->issued_releases = 0;
 
@@ -1368,6 +1368,8 @@  dlb2_hw_create_dir_port(struct dlb2_eventdev *dlb2,
 
 	qm_port->dequeue_depth = dequeue_depth;
 
+	/* Directed ports are auto-pop, by default. */
+	qm_port->token_pop_mode = AUTO_POP;
 	qm_port->owed_tokens = 0;
 	qm_port->issued_releases = 0;
 
@@ -2615,6 +2617,14 @@  dlb2_event_enqueue_burst(void *event_port,
 		dlb2_event_build_hcws(qm_port, &events[i], j,
 				      sched_types, queue_ids);
 
+		if (qm_port->token_pop_mode == DELAYED_POP && j < 4 &&
+		    qm_port->issued_releases >= qm_port->token_pop_thresh - 1) {
+			dlb2_construct_token_pop_qe(qm_port, j);
+
+			/* Reset the releases counter for the next QE batch */
+			qm_port->issued_releases -= qm_port->token_pop_thresh;
+		}
+
 		dlb2_hw_do_enqueue(qm_port, i == 0, port_data);
 
 		cnt += j;
@@ -2623,6 +2633,11 @@  dlb2_event_enqueue_burst(void *event_port,
 			break;
 	}
 
+	if (qm_port->token_pop_mode == DELAYED_POP &&
+	    qm_port->issued_releases >= qm_port->token_pop_thresh - 1) {
+		dlb2_consume_qe_immediate(qm_port, qm_port->owed_tokens);
+		qm_port->issued_releases -= qm_port->token_pop_thresh;
+	}
 	return cnt;
 }
 
@@ -3105,11 +3120,25 @@  dlb2_event_release(struct dlb2_eventdev *dlb2,
 		if (j == 0)
 			break;
 
+		if (qm_port->token_pop_mode == DELAYED_POP && j < 4 &&
+		    qm_port->issued_releases >= qm_port->token_pop_thresh - 1) {
+			dlb2_construct_token_pop_qe(qm_port, j);
+
+			/* Reset the releases counter for the next QE batch */
+			qm_port->issued_releases -= qm_port->token_pop_thresh;
+		}
+
 		dlb2_hw_do_enqueue(qm_port, i == 0, port_data);
 
 		cnt += j;
 	}
 
+	if (qm_port->token_pop_mode == DELAYED_POP &&
+	    qm_port->issued_releases >= qm_port->token_pop_thresh - 1) {
+		dlb2_consume_qe_immediate(qm_port, qm_port->owed_tokens);
+		qm_port->issued_releases -= qm_port->token_pop_thresh;
+	}
+
 sw_credit_update:
 	/* each release returns one credit */
 	if (!ev_port->outstanding_releases) {
@@ -3193,8 +3222,8 @@  dlb2_hw_dequeue_sparse(struct dlb2_eventdev *dlb2,
 	qm_port->owed_tokens += num;
 
 	if (num) {
-
-		dlb2_consume_qe_immediate(qm_port, num);
+		if (qm_port->token_pop_mode == AUTO_POP)
+			dlb2_consume_qe_immediate(qm_port, num);
 
 		ev_port->outstanding_releases += num;
 
@@ -3320,8 +3349,8 @@  dlb2_hw_dequeue(struct dlb2_eventdev *dlb2,
 	qm_port->owed_tokens += num;
 
 	if (num) {
-
-		dlb2_consume_qe_immediate(qm_port, num);
+		if (qm_port->token_pop_mode == AUTO_POP)
+			dlb2_consume_qe_immediate(qm_port, num);
 
 		ev_port->outstanding_releases += num;
 
@@ -3336,6 +3365,7 @@  dlb2_event_dequeue_burst(void *event_port, struct rte_event *ev, uint16_t num,
 			 uint64_t wait)
 {
 	struct dlb2_eventdev_port *ev_port = event_port;
+	struct dlb2_port *qm_port = &ev_port->qm_port;
 	struct dlb2_eventdev *dlb2 = ev_port->dlb2;
 	uint16_t cnt;
 
@@ -3351,6 +3381,9 @@  dlb2_event_dequeue_burst(void *event_port, struct rte_event *ev, uint16_t num,
 		DLB2_INC_STAT(ev_port->stats.tx_implicit_rel, out_rels);
 	}
 
+	if (qm_port->token_pop_mode == DEFERRED_POP && qm_port->owed_tokens)
+		dlb2_consume_qe_immediate(qm_port, qm_port->owed_tokens);
+
 	cnt = dlb2_hw_dequeue(dlb2, ev_port, ev, num, wait);
 
 	DLB2_INC_STAT(ev_port->stats.traffic.total_polls, 1);
@@ -3370,6 +3403,7 @@  dlb2_event_dequeue_burst_sparse(void *event_port, struct rte_event *ev,
 				uint16_t num, uint64_t wait)
 {
 	struct dlb2_eventdev_port *ev_port = event_port;
+	struct dlb2_port *qm_port = &ev_port->qm_port;
 	struct dlb2_eventdev *dlb2 = ev_port->dlb2;
 	uint16_t cnt;
 
@@ -3385,6 +3419,9 @@  dlb2_event_dequeue_burst_sparse(void *event_port, struct rte_event *ev,
 		DLB2_INC_STAT(ev_port->stats.tx_implicit_rel, out_rels);
 	}
 
+	if (qm_port->token_pop_mode == DEFERRED_POP && qm_port->owed_tokens)
+		dlb2_consume_qe_immediate(qm_port, qm_port->owed_tokens);
+
 	cnt = dlb2_hw_dequeue_sparse(dlb2, ev_port, ev, num, wait);
 
 	DLB2_INC_STAT(ev_port->stats.traffic.total_polls, 1);
@@ -3689,7 +3726,7 @@  dlb2_primary_eventdev_probe(struct rte_eventdev *dev,
 			    struct dlb2_devargs *dlb2_args)
 {
 	struct dlb2_eventdev *dlb2;
-	int err;
+	int err, i;
 
 	dlb2 = dev->data->dev_private;
 
@@ -3739,6 +3776,10 @@  dlb2_primary_eventdev_probe(struct rte_eventdev *dev,
 		return err;
 	}
 
+	/* Initialize each port's token pop mode */
+	for (i = 0; i < DLB2_MAX_NUM_PORTS; i++)
+		dlb2->ev_ports[i].qm_port.token_pop_mode = AUTO_POP;
+
 	rte_spinlock_init(&dlb2->qm_instance.resource_lock);
 
 	dlb2_iface_low_level_io_init();
diff --git a/drivers/event/dlb2/dlb2_priv.h b/drivers/event/dlb2/dlb2_priv.h
index 61567a6..b73cf3f 100644
--- a/drivers/event/dlb2/dlb2_priv.h
+++ b/drivers/event/dlb2/dlb2_priv.h
@@ -12,6 +12,7 @@ 
 #include <rte_config.h>
 #include "dlb2_user.h"
 #include "dlb2_log.h"
+#include "rte_pmd_dlb2.h"
 
 #ifndef RTE_LIBRTE_PMD_DLB2_QUELL_STATS
 #define DLB2_INC_STAT(_stat, _incr_val) ((_stat) += _incr_val)
@@ -290,6 +291,7 @@  struct dlb2_port {
 	bool gen_bit;
 	uint16_t dir_credits;
 	uint32_t dequeue_depth;
+	enum dlb2_token_pop_mode token_pop_mode;
 	union dlb2_port_config cfg;
 	uint32_t *credit_pool[DLB2_NUM_QUEUE_TYPES]; /* use __atomic builtins */
 	uint16_t cached_ldb_credits;
@@ -298,6 +300,7 @@  struct dlb2_port {
 	bool int_armed;
 	uint16_t owed_tokens;
 	int16_t issued_releases;
+	int16_t token_pop_thresh;
 	int cq_depth;
 	uint16_t cq_idx;
 	uint16_t cq_idx_unmasked;
diff --git a/drivers/event/dlb2/meson.build b/drivers/event/dlb2/meson.build
index 6bf8adf..539773c 100644
--- a/drivers/event/dlb2/meson.build
+++ b/drivers/event/dlb2/meson.build
@@ -1,3 +1,4 @@ 
+
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright(c) 2019-2020 Intel Corporation
 
@@ -6,7 +7,9 @@  sources = files('dlb2.c',
 		'dlb2_xstats.c',
 		'pf/dlb2_main.c',
 		'pf/dlb2_pf.c',
-		'pf/base/dlb2_resource.c'
+		'pf/base/dlb2_resource.c',
+		'rte_pmd_dlb2.c'
 )
 
 deps += ['mbuf', 'mempool', 'ring', 'pci', 'bus_pci']
+install_headers('rte_pmd_dlb2.h')
diff --git a/drivers/event/dlb2/rte_pmd_dlb2.c b/drivers/event/dlb2/rte_pmd_dlb2.c
new file mode 100644
index 0000000..b09b585
--- /dev/null
+++ b/drivers/event/dlb2/rte_pmd_dlb2.c
@@ -0,0 +1,39 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2020 Intel Corporation
+ */
+
+#include <rte_eventdev.h>
+#include <rte_eventdev_pmd.h>
+
+#include "rte_pmd_dlb2.h"
+#include "dlb2_priv.h"
+#include "dlb2_inline_fns.h"
+
+int
+rte_pmd_dlb2_set_token_pop_mode(uint8_t dev_id,
+				uint8_t port_id,
+				enum dlb2_token_pop_mode mode)
+{
+	struct dlb2_eventdev *dlb2;
+	struct rte_eventdev *dev;
+
+	RTE_EVENTDEV_VALID_DEVID_OR_ERR_RET(dev_id, -EINVAL);
+	dev = &rte_eventdevs[dev_id];
+
+	dlb2 = dlb2_pmd_priv(dev);
+
+	if (mode >= NUM_TOKEN_POP_MODES)
+		return -EINVAL;
+
+	/* The event device must be configured, but not yet started */
+	if (!dlb2->configured || dlb2->run_state != DLB2_RUN_STATE_STOPPED)
+		return -EINVAL;
+
+	/* The token pop mode must be set before configuring the port */
+	if (port_id >= dlb2->num_ports || dlb2->ev_ports[port_id].setup_done)
+		return -EINVAL;
+
+	dlb2->ev_ports[port_id].qm_port.token_pop_mode = mode;
+
+	return 0;
+}
diff --git a/drivers/event/dlb2/rte_pmd_dlb2.h b/drivers/event/dlb2/rte_pmd_dlb2.h
new file mode 100644
index 0000000..489693f
--- /dev/null
+++ b/drivers/event/dlb2/rte_pmd_dlb2.h
@@ -0,0 +1,68 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2020 Intel Corporation
+ */
+
+/*!
+ *  @file      rte_pmd_dlb2.h
+ *
+ *  @brief     DLB PMD-specific functions
+ *
+ *  @b EXPERIMENTAL: this API may change, or be removed, without prior notice
+ */
+
+#ifndef _RTE_PMD_DLB2_H_
+#define _RTE_PMD_DLB2_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+/**
+ * Selects the token pop mode for a DLB2 port.
+ */
+enum dlb2_token_pop_mode {
+	/* Pop the CQ tokens immediately after dequeueing. */
+	AUTO_POP,
+	/* Pop CQ tokens after (dequeue_depth - 1) events are released.
+	 * Supported on load-balanced ports only.
+	 */
+	DELAYED_POP,
+	/* Pop the CQ tokens during next dequeue operation. */
+	DEFERRED_POP,
+
+	/* NUM_TOKEN_POP_MODES must be last */
+	NUM_TOKEN_POP_MODES
+};
+
+/*!
+ * Configure the token pop mode for a DLB2 port. By default, all ports use
+ * AUTO_POP. This function must be called before calling rte_event_port_setup()
+ * for the port, but after calling rte_event_dev_configure().
+ *
+ * @param dev_id
+ *    The identifier of the event device.
+ * @param port_id
+ *    The identifier of the event port.
+ * @param mode
+ *    The token pop mode.
+ *
+ * @return
+ * - 0: Success
+ * - EINVAL: Invalid dev_id, port_id, or mode
+ * - EINVAL: The DLB2 is not configured, is already running, or the port is
+ *   already setup
+ */
+
+__rte_experimental
+int
+rte_pmd_dlb2_set_token_pop_mode(uint8_t dev_id,
+				uint8_t port_id,
+				enum dlb2_token_pop_mode mode);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_PMD_DLB2_H_ */
diff --git a/drivers/event/dlb2/rte_pmd_dlb2_event_version.map b/drivers/event/dlb2/rte_pmd_dlb2_event_version.map
index 299ae63..84b81a4 100644
--- a/drivers/event/dlb2/rte_pmd_dlb2_event_version.map
+++ b/drivers/event/dlb2/rte_pmd_dlb2_event_version.map
@@ -1,3 +1,9 @@ 
 DPDK_21.0 {
 	local: *;
 };
+
+EXPERIMENTAL {
+	global:
+
+	rte_pmd_dlb2_set_token_pop_mode;
+};