[dpdk-dev] [PATCH v3 1/4] ethdev: Add eal device event callback

[Jeff Guo <jia.guo@intel.com>]

Implement a eal device event callback "rte_eth_dev_event_callback"
in ethdev, it could let pmd driver have chance to manage the eal
device event, such as process hotplug event.

Signed-off-by: Jeff Guo <jia.guo@intel.com>
---
v3->v2:
add new callback in ethdev
---
 doc/guides/rel_notes/release_18_08.rst |  8 ++++++++
 lib/librte_ethdev/rte_ethdev.c         | 37 ++++++++++++++++++++++++++++++++++
 lib/librte_ethdev/rte_ethdev_driver.h  | 20 ++++++++++++++++++
 3 files changed, 65 insertions(+)

diff --git a/doc/guides/rel_notes/release_18_08.rst b/doc/guides/rel_notes/release_18_08.rst
index bc01242..2326058 100644
--- a/doc/guides/rel_notes/release_18_08.rst
+++ b/doc/guides/rel_notes/release_18_08.rst
@@ -46,6 +46,14 @@ New Features
   Flow API support has been added to CXGBE Poll Mode Driver to offload
   flows to Chelsio T5/T6 NICs.
 
+* **Added eal device event callback in ethdev for hotplug.**
+
+  Implement a eal device event callback in ethdev, it could let pmd driver
+  have chance to manage the eal device event, such as process hotplug event.
+
+  * ``rte_eth_dev_event_callback`` for driver use to register it and process
+    eal device event.
+
 
 API Changes
 -----------
diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
index a9977df..36f218a 100644
--- a/lib/librte_ethdev/rte_ethdev.c
+++ b/lib/librte_ethdev/rte_ethdev.c
@@ -4518,6 +4518,43 @@ rte_eth_devargs_parse(const char *dargs, struct rte_eth_devargs *eth_da)
 	return result;
 }
 
+void __rte_experimental
+rte_eth_dev_event_callback(char *device_name, enum rte_dev_event_type type,
+			     void *arg)
+{
+	struct rte_eth_dev *eth_dev = (struct rte_eth_dev *)arg;
+
+	if (type >= RTE_DEV_EVENT_MAX) {
+		fprintf(stderr, "%s called upon invalid event %d\n",
+			__func__, type);
+		fflush(stderr);
+	}
+
+	switch (type) {
+	case RTE_DEV_EVENT_REMOVE:
+		ethdev_log(INFO, "The device: %s has been removed!\n",
+			    device_name);
+
+		if (!device_name || !eth_dev)
+			return;
+
+		if (!(eth_dev->data->dev_flags & RTE_ETH_EVENT_INTR_RMV))
+			return;
+
+		if (!strcmp(device_name, eth_dev->device->name))
+			_rte_eth_dev_callback_process(eth_dev,
+						      RTE_ETH_EVENT_INTR_RMV,
+						      NULL);
+		break;
+	case RTE_DEV_EVENT_ADD:
+		ethdev_log(INFO, "The device: %s has been added!\n",
+			device_name);
+		break;
+	default:
+		break;
+	}
+}
+
 RTE_INIT(ethdev_init_log);
 static void
 ethdev_init_log(void)
diff --git a/lib/librte_ethdev/rte_ethdev_driver.h b/lib/librte_ethdev/rte_ethdev_driver.h
index c9c825e..fed5afa 100644
--- a/lib/librte_ethdev/rte_ethdev_driver.h
+++ b/lib/librte_ethdev/rte_ethdev_driver.h
@@ -82,6 +82,26 @@ int rte_eth_dev_release_port(struct rte_eth_dev *eth_dev);
 void _rte_eth_dev_reset(struct rte_eth_dev *dev);
 
 /**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Implement a rte eth eal device event callbacks for the specific device.
+ *
+ * @param device_name
+ *  Pointer to the name of the rte device.
+ * @param event
+ *  Eal device event type.
+ * @param ret_param
+ *  To pass data back to user application.
+ *
+ * @return
+ *  void
+ */
+void __rte_experimental
+rte_eth_dev_event_callback(char *device_name,
+		enum rte_dev_event_type event, void *cb_arg);
+
+/**
  * @internal Executes all the user application registered callbacks for
  * the specific device. It is for DPDK internal user only. User
  * application should not call it directly.
-- 
2.7.4