[dpdk-dev] [PATCH v5 5/7] event/sw: enable SW PMD with service capability

[Harry van Haaren]

This commit shows how easy it is to enable a specific
DPDK component with a service callback, in order to get
CPU cycles for it.

The beauty of this method is that the service is unaware
of how much CPU time it is getting - the application can
decide how to split and slice cores and map them to the
registered services.

Signed-off-by: Harry van Haaren <harry.van.haa...@intel.com>
Acked-by: Jerin Jacob <jerin.ja...@caviumnetworks.com>

---

v4:
- Include Acked by

v2:
- Remove #include <rte_cycles.h> (Jerin)
- Remove development prints (Jerin)
- Track service name in PMD
- Print warning if service does not have an lcore mapped (Jerin)
---
 drivers/event/sw/sw_evdev.c | 32 ++++++++++++++++++++++++++++++++
 drivers/event/sw/sw_evdev.h |  3 +++
 2 files changed, 35 insertions(+)

diff --git a/drivers/event/sw/sw_evdev.c b/drivers/event/sw/sw_evdev.c
index 5b33bfd..9c534b7 100644
--- a/drivers/event/sw/sw_evdev.c
+++ b/drivers/event/sw/sw_evdev.c
@@ -39,6 +39,7 @@
 #include <rte_ring.h>
 #include <rte_errno.h>
 #include <rte_event_ring.h>
+#include <rte_service_component.h>
 
 #include "sw_evdev.h"
 #include "iq_ring.h"
@@ -614,6 +615,13 @@ sw_start(struct rte_eventdev *dev)
 {
        unsigned int i, j;
        struct sw_evdev *sw = sw_pmd_priv(dev);
+
+       /* check a service core is mapped to this service */
+       struct rte_service_spec *s = rte_service_get_by_name(sw->service_name);
+       if (!rte_service_is_running(s))
+               SW_LOG_ERR("Warning: No Service core enabled on service %s\n",
+                               s->name);
+
        /* check all ports are set up */
        for (i = 0; i < sw->port_count; i++)
                if (sw->ports[i].rx_worker_ring == NULL) {
@@ -716,6 +724,14 @@ set_credit_quanta(const char *key __rte_unused, const char 
*value, void *opaque)
        return 0;
 }
 
+
+static int32_t sw_sched_service_func(void *args)
+{
+       struct rte_eventdev *dev = args;
+       sw_event_schedule(dev);
+       return 0;
+}
+
 static int
 sw_probe(struct rte_vdev_device *vdev)
 {
@@ -829,6 +845,22 @@ sw_probe(struct rte_vdev_device *vdev)
        sw->credit_update_quanta = credit_quanta;
        sw->sched_quanta = sched_quanta;
 
+       /* register service with EAL */
+       struct rte_service_spec service;
+       memset(&service, 0, sizeof(struct rte_service_spec));
+       snprintf(service.name, sizeof(service.name), "%s_service", name);
+       snprintf(sw->service_name, sizeof(sw->service_name), "%s_service",
+                       name);
+       service.socket_id = socket_id;
+       service.callback = sw_sched_service_func;
+       service.callback_userdata = (void *)dev;
+
+       int32_t ret = rte_service_register(&service);
+       if (ret) {
+               SW_LOG_ERR("service register() failed");
+               return -ENOEXEC;
+       }
+
        return 0;
 }
 
diff --git a/drivers/event/sw/sw_evdev.h b/drivers/event/sw/sw_evdev.h
index 6ef03ce..71de3c1 100644
--- a/drivers/event/sw/sw_evdev.h
+++ b/drivers/event/sw/sw_evdev.h
@@ -59,6 +59,7 @@
 
 #define EVENTDEV_NAME_SW_PMD event_sw
 #define SW_PMD_NAME RTE_STR(event_sw)
+#define SW_PMD_NAME_MAX 64
 
 #define SW_SCHED_TYPE_DIRECT (RTE_SCHED_TYPE_PARALLEL + 1)
 
@@ -276,6 +277,8 @@ struct sw_evdev {
        /* store num stats and offset of the stats for each queue */
        uint16_t xstats_count_per_qid[RTE_EVENT_MAX_QUEUES_PER_DEV];
        uint16_t xstats_offset_for_qid[RTE_EVENT_MAX_QUEUES_PER_DEV];
+
+       char service_name[SW_PMD_NAME_MAX];
 };
 
 static inline struct sw_evdev *
-- 
2.7.4