[ovs-dev] [PATCH v3 1/3] netdev-dpdk: Remove dpdk watchdog thread

[Ciara Loftus]

Instead of continuously polling for link status changes on 'dpdk'
ports, register a callback function that will be triggered when DPDK
detects that the link status of that port has changed.

Signed-off-by: Ciara Loftus <ciara.loftus at intel.com>
Suggested-by: Kevin Traynor <kevin.traynor at intel.com>
---
 lib/netdev-dpdk.c | 55 ++++++++++++++++++++++++++++++-------------------------
 1 file changed, 30 insertions(+), 25 deletions(-)

diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
index af86d19..89d783a 100644
--- a/lib/netdev-dpdk.c
+++ b/lib/netdev-dpdk.c
@@ -62,8 +62,6 @@
 VLOG_DEFINE_THIS_MODULE(dpdk);
 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(5, 20);
 
-#define DPDK_PORT_WATCHDOG_INTERVAL 5
-
 #define OVS_CACHE_LINE_SIZE CACHE_LINE_SIZE
 #define OVS_VPORT_DPDK "ovs_dpdk"
 
@@ -386,6 +384,9 @@ static int netdev_dpdk_construct(struct netdev *);
 
 struct virtio_net * netdev_dpdk_get_virtio(const struct netdev_dpdk *dev);
 
+void link_status_changed_callback(uint8_t port_id,
+        enum rte_eth_event_type type OVS_UNUSED, void *param OVS_UNUSED);
+
 static bool
 is_dpdk_class(const struct netdev_class *class)
 {
@@ -536,27 +537,6 @@ check_link_status(struct netdev_dpdk *dev)
     }
 }
 
-static void *
-dpdk_watchdog(void *dummy OVS_UNUSED)
-{
-    struct netdev_dpdk *dev;
-
-    pthread_detach(pthread_self());
-
-    for (;;) {
-        ovs_mutex_lock(&dpdk_mutex);
-        LIST_FOR_EACH (dev, list_node, &dpdk_list) {
-            ovs_mutex_lock(&dev->mutex);
-            check_link_status(dev);
-            ovs_mutex_unlock(&dev->mutex);
-        }
-        ovs_mutex_unlock(&dpdk_mutex);
-        xsleep(DPDK_PORT_WATCHDOG_INTERVAL);
-    }
-
-    return NULL;
-}
-
 static int
 dpdk_eth_dev_queue_setup(struct netdev_dpdk *dev, int n_rxq, int n_txq)
 {
@@ -717,6 +697,27 @@ netdev_dpdk_alloc_txq(struct netdev_dpdk *dev, unsigned int n_txqs)
     }
 }
 
+void
+link_status_changed_callback(uint8_t port_id,
+                              enum rte_eth_event_type type OVS_UNUSED,
+                              void *param OVS_UNUSED)
+{
+    struct netdev_dpdk *dev;
+
+    ovs_mutex_lock(&dpdk_mutex);
+    LIST_FOR_EACH (dev, list_node, &dpdk_list) {
+        if (port_id == dev->port_id) {
+            ovs_mutex_lock(&dev->mutex);
+            check_link_status(dev);
+            ovs_mutex_unlock(&dev->mutex);
+            break;
+        }
+    }
+    ovs_mutex_unlock(&dpdk_mutex);
+
+    return;
+}
+
 static int
 netdev_dpdk_init(struct netdev *netdev, unsigned int port_no,
                  enum dpdk_dev_type type)
@@ -774,6 +775,12 @@ netdev_dpdk_init(struct netdev *netdev, unsigned int port_no,
         netdev_dpdk_alloc_txq(dev, OVS_VHOST_MAX_QUEUE_NUM);
     }
 
+    if (type == DPDK_DEV_ETH) {
+        rte_eth_dev_callback_register(port_no, RTE_ETH_EVENT_INTR_LSC,
+                                     (void*)link_status_changed_callback,
+                                      NULL);
+    }
+
     ovs_list_push_back(&dpdk_list, &dev->list_node);
 
 unlock:
@@ -3207,8 +3214,6 @@ dpdk_init__(const struct smap *ovs_other_config)
     /* We are called from the main thread here */
     RTE_PER_LCORE(_lcore_id) = NON_PMD_CORE_ID;
 
-    ovs_thread_create("dpdk_watchdog", dpdk_watchdog, NULL);
-
 #ifdef VHOST_CUSE
     /* Register CUSE device to handle IOCTLs.
      * Unless otherwise specified, cuse_dev_name is set to vhost-net.
-- 
2.4.3