event/dlb: add token pop API

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>
Reviewed-by: Gage Eads <gage.eads@intel.com>

diff --git a/doc/api/doxy-api-index.md b/doc/api/doxy-api-index.md
index e1836dc..4356cd3 100644 (file)
--- a/doc/api/doxy-api-index.md
+++ b/doc/api/doxy-api-index.md
@@ -53,6 +53,7 @@ The public API headers are grouped by topics:
   [dpaa2_cmdif]        (@ref rte_pmd_dpaa2_cmdif.h),
   [dpaa2_qdma]         (@ref rte_pmd_dpaa2_qdma.h),
   [crypto_scheduler]   (@ref rte_cryptodev_scheduler.h),
+  [dlb]                (@ref rte_pmd_dlb.h),
   [dlb2]               (@ref rte_pmd_dlb2.h)
 
 - **memory**:

diff --git a/doc/api/doxy-api.conf.in b/doc/api/doxy-api.conf.in
index 535321f..98d45c0 100644 (file)
--- a/doc/api/doxy-api.conf.in
+++ b/doc/api/doxy-api.conf.in
@@ -7,6 +7,7 @@ USE_MDFILE_AS_MAINPAGE  = @TOPDIR@/doc/api/doxy-api-index.md
 INPUT                   = @TOPDIR@/doc/api/doxy-api-index.md \
                           @TOPDIR@/drivers/bus/vdev \
                           @TOPDIR@/drivers/crypto/scheduler \
+                          @TOPDIR@/drivers/event/dlb \
                           @TOPDIR@/drivers/event/dlb2 \
                           @TOPDIR@/drivers/mempool/dpaa2 \
                           @TOPDIR@/drivers/net/ark \

diff --git a/drivers/event/dlb/dlb.c b/drivers/event/dlb/dlb.c
index 95b7bbe..e59a0de 100644 (file)
--- a/drivers/event/dlb/dlb.c
+++ b/drivers/event/dlb/dlb.c
@@ -72,6 +72,25 @@ static struct rte_event_dev_info evdev_dlb_default_info = {
 struct process_local_port_data
 dlb_port[DLB_MAX_NUM_PORTS][NUM_DLB_PORT_TYPES];
 
+static inline uint16_t
+dlb_event_enqueue_delayed(void *event_port,
+                         const struct rte_event events[]);
+
+static inline uint16_t
+dlb_event_enqueue_burst_delayed(void *event_port,
+                               const struct rte_event events[],
+                               uint16_t num);
+
+static inline uint16_t
+dlb_event_enqueue_new_burst_delayed(void *event_port,
+                                   const struct rte_event events[],
+                                   uint16_t num);
+
+static inline uint16_t
+dlb_event_enqueue_forward_burst_delayed(void *event_port,
+                                       const struct rte_event events[],
+                                       uint16_t num);
+
 static int
 dlb_hw_query_resources(struct dlb_eventdev *dlb)
 {
@@ -1003,6 +1022,33 @@ dlb_hw_create_ldb_port(struct dlb_eventdev *dlb,
 
        qm_port->dequeue_depth = dequeue_depth;
 
+       /* When using the reserved token scheme, token_pop_thresh is
+        * initially 2 * dequeue_depth. Once the tokens are reserved,
+        * the enqueue code re-assigns it to dequeue_depth.
+        */
+       qm_port->token_pop_thresh = cq_depth;
+
+       /* When the deferred scheduling vdev arg is selected, use deferred pop
+        * for all single-entry CQs.
+        */
+       if (cfg.cq_depth == 1 || (cfg.cq_depth == 2 && use_rsvd_token_scheme)) {
+               if (dlb->defer_sched)
+                       qm_port->token_pop_mode = DEFERRED_POP;
+       }
+
+       /* The default enqueue functions do not include delayed-pop support for
+        * performance reasons.
+        */
+       if (qm_port->token_pop_mode == DELAYED_POP) {
+               dlb->event_dev->enqueue = dlb_event_enqueue_delayed;
+               dlb->event_dev->enqueue_burst =
+                       dlb_event_enqueue_burst_delayed;
+               dlb->event_dev->enqueue_new_burst =
+                       dlb_event_enqueue_new_burst_delayed;
+               dlb->event_dev->enqueue_forward_burst =
+                       dlb_event_enqueue_forward_burst_delayed;
+       }
+
        qm_port->owed_tokens = 0;
        qm_port->issued_releases = 0;
 
@@ -1163,6 +1209,8 @@ dlb_hw_create_dir_port(struct dlb_eventdev *dlb,
 
        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;
 
@@ -2572,6 +2620,30 @@ dlb_event_build_hcws(struct dlb_port *qm_port,
        }
 }
 
+static inline void
+dlb_construct_token_pop_qe(struct dlb_port *qm_port, int idx)
+{
+       struct dlb_cq_pop_qe *qe = (void *)qm_port->qe4;
+       int num = qm_port->owed_tokens;
+
+       if (qm_port->use_rsvd_token_scheme) {
+               /* Check if there's a deficit of reserved tokens, and return
+                * early if there are no (unreserved) tokens to consume.
+                */
+               if (num <= qm_port->cq_rsvd_token_deficit) {
+                       qm_port->cq_rsvd_token_deficit -= num;
+                       qm_port->owed_tokens = 0;
+                       return;
+               }
+               num -= qm_port->cq_rsvd_token_deficit;
+               qm_port->cq_rsvd_token_deficit = 0;
+       }
+
+       qe[idx].cmd_byte = DLB_POP_CMD_BYTE;
+       qe[idx].tokens = num - 1;
+       qm_port->owed_tokens = 0;
+}
+
 static __rte_always_inline void
 dlb_pp_write(struct dlb_enqueue_qe *qe4,
             struct process_local_port_data *port_data)
@@ -2638,7 +2710,8 @@ dlb_consume_qe_immediate(struct dlb_port *qm_port, int num)
 static inline uint16_t
 __dlb_event_enqueue_burst(void *event_port,
                          const struct rte_event events[],
-                         uint16_t num)
+                         uint16_t num,
+                         bool use_delayed)
 {
        struct dlb_eventdev_port *ev_port = event_port;
        struct dlb_port *qm_port = &ev_port->qm_port;
@@ -2666,6 +2739,35 @@ __dlb_event_enqueue_burst(void *event_port,
 
                for (; j < DLB_NUM_QES_PER_CACHE_LINE && (i + j) < num; j++) {
                        const struct rte_event *ev = &events[i + j];
+                       int16_t thresh = qm_port->token_pop_thresh;
+
+                       if (use_delayed &&
+                           qm_port->token_pop_mode == DELAYED_POP &&
+                           (ev->op == RTE_EVENT_OP_FORWARD ||
+                            ev->op == RTE_EVENT_OP_RELEASE) &&
+                           qm_port->issued_releases >= thresh - 1) {
+                               /* Insert the token pop QE and break out. This
+                                * may result in a partial HCW, but that is
+                                * simpler than supporting arbitrary QE
+                                * insertion.
+                                */
+                               dlb_construct_token_pop_qe(qm_port, j);
+
+                               /* Reset the releases for the next QE batch */
+                               qm_port->issued_releases -= thresh;
+
+                               /* When using delayed token pop mode, the
+                                * initial token threshold is the full CQ
+                                * depth. After the first token pop, we need to
+                                * reset it to the dequeue_depth.
+                                */
+                               qm_port->token_pop_thresh =
+                                       qm_port->dequeue_depth;
+
+                               pop_offs = 1;
+                               j++;
+                               break;
+                       }
 
                        if (dlb_event_enqueue_prep(ev_port, qm_port, ev,
                                                   port_data, &sched_types[j],
@@ -2701,14 +2803,29 @@ dlb_event_enqueue_burst(void *event_port,
                        const struct rte_event events[],
                        uint16_t num)
 {
-       return __dlb_event_enqueue_burst(event_port, events, num);
+       return __dlb_event_enqueue_burst(event_port, events, num, false);
+}
+
+static inline uint16_t
+dlb_event_enqueue_burst_delayed(void *event_port,
+                               const struct rte_event events[],
+                               uint16_t num)
+{
+       return __dlb_event_enqueue_burst(event_port, events, num, true);
 }
 
 static inline uint16_t
 dlb_event_enqueue(void *event_port,
                  const struct rte_event events[])
 {
-       return __dlb_event_enqueue_burst(event_port, events, 1);
+       return __dlb_event_enqueue_burst(event_port, events, 1, false);
+}
+
+static inline uint16_t
+dlb_event_enqueue_delayed(void *event_port,
+                         const struct rte_event events[])
+{
+       return __dlb_event_enqueue_burst(event_port, events, 1, true);
 }
 
 static uint16_t
@@ -2716,7 +2833,15 @@ dlb_event_enqueue_new_burst(void *event_port,
                            const struct rte_event events[],
                            uint16_t num)
 {
-       return __dlb_event_enqueue_burst(event_port, events, num);
+       return __dlb_event_enqueue_burst(event_port, events, num, false);
+}
+
+static uint16_t
+dlb_event_enqueue_new_burst_delayed(void *event_port,
+                                   const struct rte_event events[],
+                                   uint16_t num)
+{
+       return __dlb_event_enqueue_burst(event_port, events, num, true);
 }
 
 static uint16_t
@@ -2724,7 +2849,15 @@ dlb_event_enqueue_forward_burst(void *event_port,
                                const struct rte_event events[],
                                uint16_t num)
 {
-       return __dlb_event_enqueue_burst(event_port, events, num);
+       return __dlb_event_enqueue_burst(event_port, events, num, false);
+}
+
+static uint16_t
+dlb_event_enqueue_forward_burst_delayed(void *event_port,
+                                       const struct rte_event events[],
+                                       uint16_t num)
+{
+       return __dlb_event_enqueue_burst(event_port, events, num, true);
 }
 
 static __rte_always_inline int
@@ -3124,7 +3257,8 @@ dlb_hw_dequeue(struct dlb_eventdev *dlb,
 
        qm_port->owed_tokens += num;
 
-       dlb_consume_qe_immediate(qm_port, num);
+       if (num && qm_port->token_pop_mode == AUTO_POP)
+               dlb_consume_qe_immediate(qm_port, num);
 
        ev_port->outstanding_releases += num;
 
@@ -3249,7 +3383,8 @@ dlb_hw_dequeue_sparse(struct dlb_eventdev *dlb,
 
        qm_port->owed_tokens += num;
 
-       dlb_consume_qe_immediate(qm_port, num);
+       if (num && qm_port->token_pop_mode == AUTO_POP)
+               dlb_consume_qe_immediate(qm_port, num);
 
        ev_port->outstanding_releases += num;
 
@@ -3293,6 +3428,28 @@ dlb_event_release(struct dlb_eventdev *dlb, uint8_t port_id, int n)
                qm_port->qe4[3].cmd_byte = 0;
 
                for (; j < DLB_NUM_QES_PER_CACHE_LINE && (i + j) < n; j++) {
+                       int16_t thresh = qm_port->token_pop_thresh;
+
+                       if (qm_port->token_pop_mode == DELAYED_POP &&
+                           qm_port->issued_releases >= thresh - 1) {
+                               /* Insert the token pop QE */
+                               dlb_construct_token_pop_qe(qm_port, j);
+
+                               /* Reset the releases for the next QE batch */
+                               qm_port->issued_releases -= thresh;
+
+                               /* When using delayed token pop mode, the
+                                * initial token threshold is the full CQ
+                                * depth. After the first token pop, we need to
+                                * reset it to the dequeue_depth.
+                                */
+                               qm_port->token_pop_thresh =
+                                       qm_port->dequeue_depth;
+
+                               pop_offs = 1;
+                               j++;
+                               break;
+                       }
 
                        qm_port->qe4[j].cmd_byte = DLB_COMP_CMD_BYTE;
                        qm_port->issued_releases++;
@@ -3325,6 +3482,7 @@ dlb_event_dequeue_burst(void *event_port, struct rte_event *ev, uint16_t num,
                        uint64_t wait)
 {
        struct dlb_eventdev_port *ev_port = event_port;
+       struct dlb_port *qm_port = &ev_port->qm_port;
        struct dlb_eventdev *dlb = ev_port->dlb;
        uint16_t cnt;
        int ret;
@@ -3344,6 +3502,10 @@ dlb_event_dequeue_burst(void *event_port, struct rte_event *ev, uint16_t num,
                DLB_INC_STAT(ev_port->stats.tx_implicit_rel, out_rels);
        }
 
+       if (qm_port->token_pop_mode == DEFERRED_POP &&
+                       qm_port->owed_tokens)
+               dlb_consume_qe_immediate(qm_port, qm_port->owed_tokens);
+
        cnt = dlb_hw_dequeue(dlb, ev_port, ev, num, wait);
 
        DLB_INC_STAT(ev_port->stats.traffic.total_polls, 1);
@@ -3362,6 +3524,7 @@ dlb_event_dequeue_burst_sparse(void *event_port, struct rte_event *ev,
                               uint16_t num, uint64_t wait)
 {
        struct dlb_eventdev_port *ev_port = event_port;
+       struct dlb_port *qm_port = &ev_port->qm_port;
        struct dlb_eventdev *dlb = ev_port->dlb;
        uint16_t cnt;
        int ret;
@@ -3381,6 +3544,10 @@ dlb_event_dequeue_burst_sparse(void *event_port, struct rte_event *ev,
                DLB_INC_STAT(ev_port->stats.tx_implicit_rel, out_rels);
        }
 
+       if (qm_port->token_pop_mode == DEFERRED_POP &&
+           qm_port->owed_tokens)
+               dlb_consume_qe_immediate(qm_port, qm_port->owed_tokens);
+
        cnt = dlb_hw_dequeue_sparse(dlb, ev_port, ev, num, wait);
 
        DLB_INC_STAT(ev_port->stats.traffic.total_polls, 1);
@@ -3687,7 +3854,7 @@ dlb_primary_eventdev_probe(struct rte_eventdev *dev,
                           struct dlb_devargs *dlb_args)
 {
        struct dlb_eventdev *dlb;
-       int err;
+       int err, i;
 
        dlb = dev->data->dev_private;
 
@@ -3736,6 +3903,10 @@ dlb_primary_eventdev_probe(struct rte_eventdev *dev,
                return err;
        }
 
+       /* Initialize each port's token pop mode */
+       for (i = 0; i < DLB_MAX_NUM_PORTS; i++)
+               dlb->ev_ports[i].qm_port.token_pop_mode = AUTO_POP;
+
        rte_spinlock_init(&dlb->qm_instance.resource_lock);
 
        dlb_iface_low_level_io_init(dlb);

diff --git a/drivers/event/dlb/dlb_priv.h b/drivers/event/dlb/dlb_priv.h
index adb1f7a..58ff428 100644 (file)
--- a/drivers/event/dlb/dlb_priv.h
+++ b/drivers/event/dlb/dlb_priv.h
@@ -16,6 +16,7 @@
 
 #include "dlb_user.h"
 #include "dlb_log.h"
+#include "rte_pmd_dlb.h"
 
 #ifndef RTE_LIBRTE_PMD_DLB_QUELL_STATS
 #define DLB_INC_STAT(_stat, _incr_val) ((_stat) += _incr_val)
@@ -262,6 +263,7 @@ struct dlb_port {
        bool gen_bit;
        uint16_t dir_credits;
        uint32_t dequeue_depth;
+       enum dlb_token_pop_mode token_pop_mode;
        int pp_mmio_base;
        uint16_t cached_ldb_credits;
        uint16_t ldb_pushcount_at_credit_expiry;
@@ -273,6 +275,7 @@ struct dlb_port {
        uint8_t cq_rsvd_token_deficit;
        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/dlb/meson.build b/drivers/event/dlb/meson.build
index 66a3fbe..2ea3b4c 100644 (file)
--- a/drivers/event/dlb/meson.build
+++ b/drivers/event/dlb/meson.build
@@ -12,9 +12,10 @@ sources = files('dlb.c',
                'dlb_xstats.c',
                'pf/dlb_main.c',
                'pf/dlb_pf.c',
-               'pf/base/dlb_resource.c'
+               'pf/base/dlb_resource.c',
+               'rte_pmd_dlb.c',
 )
 
-headers = files()
+headers = files('rte_pmd_dlb.h')
 
 deps += ['mbuf', 'mempool', 'ring', 'pci', 'bus_pci']

diff --git a/drivers/event/dlb/rte_pmd_dlb.c b/drivers/event/dlb/rte_pmd_dlb.c
new file mode 100644 (file)
index 0000000..bc802d3
--- /dev/null
+++ b/drivers/event/dlb/rte_pmd_dlb.c
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2020 Intel Corporation
+ */
+
+#include "rte_eventdev.h"
+#include "rte_eventdev_pmd.h"
+#include "rte_pmd_dlb.h"
+#include "dlb_priv.h"
+#include "dlb_inline_fns.h"
+
+int
+rte_pmd_dlb_set_token_pop_mode(uint8_t dev_id,
+                              uint8_t port_id,
+                              enum dlb_token_pop_mode mode)
+{
+       struct dlb_eventdev *dlb;
+       struct rte_eventdev *dev;
+
+       RTE_EVENTDEV_VALID_DEVID_OR_ERR_RET(dev_id, -EINVAL);
+       dev = &rte_eventdevs[dev_id];
+
+       dlb = dlb_pmd_priv(dev);
+
+       if (mode >= NUM_TOKEN_POP_MODES)
+               return -EINVAL;
+
+       /* The event device must be configured, but not yet started */
+       if (!dlb->configured || dlb->run_state != DLB_RUN_STATE_STOPPED)
+               return -EINVAL;
+
+       /* The token pop mode must be set before configuring the port */
+       if (port_id >= dlb->num_ports || dlb->ev_ports[port_id].setup_done)
+               return -EINVAL;
+
+       dlb->ev_ports[port_id].qm_port.token_pop_mode = mode;
+
+       return 0;
+}

diff --git a/drivers/event/dlb/rte_pmd_dlb.h b/drivers/event/dlb/rte_pmd_dlb.h
new file mode 100644 (file)
index 0000000..9cf6dd3
--- /dev/null
+++ b/drivers/event/dlb/rte_pmd_dlb.h
@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2019-2020 Intel Corporation
+ */
+
+/*!
+ *  @file      rte_pmd_dlb.h
+ *
+ *  @brief     DLB PMD-specific functions
+ *
+ */
+
+#ifndef _RTE_PMD_DLB_H_
+#define _RTE_PMD_DLB_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change, or be removed, without prior notice
+ *
+ * Selects the token pop mode for an DLB port.
+ */
+enum dlb_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
+};
+
+/*!
+ * @warning
+ * @b EXPERIMENTAL: this API may change, or be removed, without prior notice
+ *
+ * Configure the token pop mode for an DLB 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().
+ *
+ * @note
+ *    The defer_sched vdev arg, which configures all load-balanced ports with
+ *    dequeue_depth == 1 for DEFERRED_POP mode, takes precedence over this
+ *    function.
+ *
+ * @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 DLB is not configured, is already running, or the port is
+ *   already setup
+ */
+
+__rte_experimental
+int
+rte_pmd_dlb_set_token_pop_mode(uint8_t dev_id,
+                              uint8_t port_id,
+                              enum dlb_token_pop_mode mode);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_PMD_DLB_H_ */

diff --git a/drivers/event/dlb/version.map b/drivers/event/dlb/version.map
index 4a76d1d..3338a22 100644 (file)
--- a/drivers/event/dlb/version.map
+++ b/drivers/event/dlb/version.map
@@ -1,3 +1,9 @@
 DPDK_21 {
        local: *;
 };
+
+EXPERIMENTAL {
+       global:
+
+       rte_pmd_dlb_set_token_pop_mode;
+};