[PATCH v3 1/2] net/failsafe: fix removed sub-device cleanup

[Matan Azrad <matan@mellanox.com>]

The fail-safe PMD registers to RMV event for each removable sub-device
port in order to cleanup the sub-device resources and switch the Tx
sub-device directly when it is plugged-out.

During removal time, the fail-safe PMD stops and closes the sub-device
but it doesn't unregister the LSC and RMV callbacks of the sub-device
port.

It can lead the callbacks to be called for a port which is no more
associated with the fail-safe sub-device, because there is not a
guarantee that a sub-device gets the same port ID for each plug-in
process. This port, for example, may belong to another sub-device of a
different fail-safe device.

Unregister the LSC and RMV callbacks for sub-devices which are not
used.

Fixes: 598fb8aec6f6 ("net/failsafe: support device removal")
Cc: stable@dpdk.org

Signed-off-by: Matan Azrad <matan@mellanox.com>
---


V2:
Improve the commit log and add code comments for the new sub-dev fields (Ophir suggestion).

V3:
Add warning message if a sub-device event callback unregistration fails (Ophir + Gaetan suggestion). 


 drivers/net/failsafe/failsafe_ether.c   | 30 ++++++++++++++++++++++++++++++
 drivers/net/failsafe/failsafe_ops.c     |  5 +++++
 drivers/net/failsafe/failsafe_private.h |  5 +++++
 3 files changed, 40 insertions(+)

diff --git a/drivers/net/failsafe/failsafe_ether.c b/drivers/net/failsafe/failsafe_ether.c
index 733e95d..5b5cb3b 100644
--- a/drivers/net/failsafe/failsafe_ether.c
+++ b/drivers/net/failsafe/failsafe_ether.c
@@ -260,6 +260,7 @@
 		sdev->state = DEV_ACTIVE;
 		/* fallthrough */
 	case DEV_ACTIVE:
+		failsafe_eth_dev_unregister_callbacks(sdev);
 		rte_eth_dev_close(PORT_ID(sdev));
 		sdev->state = DEV_PROBED;
 		/* fallthrough */
@@ -321,6 +322,35 @@
 }
 
 void
+failsafe_eth_dev_unregister_callbacks(struct sub_device *sdev)
+{
+	int ret;
+
+	if (sdev == NULL)
+		return;
+	if (sdev->rmv_callback) {
+		ret = rte_eth_dev_callback_unregister(PORT_ID(sdev),
+						RTE_ETH_EVENT_INTR_RMV,
+						failsafe_eth_rmv_event_callback,
+						sdev);
+		if (ret)
+			WARN("Failed to unregister RMV callback for sub_device"
+			     " %d", SUB_ID(sdev));
+		sdev->rmv_callback = 0;
+	}
+	if (sdev->lsc_callback) {
+		ret = rte_eth_dev_callback_unregister(PORT_ID(sdev),
+						RTE_ETH_EVENT_INTR_LSC,
+						failsafe_eth_lsc_event_callback,
+						sdev);
+		if (ret)
+			WARN("Failed to unregister LSC callback for sub_device"
+			     " %d", SUB_ID(sdev));
+		sdev->lsc_callback = 0;
+	}
+}
+
+void
 failsafe_dev_remove(struct rte_eth_dev *dev)
 {
 	struct sub_device *sdev;
diff --git a/drivers/net/failsafe/failsafe_ops.c b/drivers/net/failsafe/failsafe_ops.c
index d04277b..e0570b6 100644
--- a/drivers/net/failsafe/failsafe_ops.c
+++ b/drivers/net/failsafe/failsafe_ops.c
@@ -146,6 +146,8 @@
 			if (ret)
 				WARN("Failed to register RMV callback for sub_device %d",
 				     SUB_ID(sdev));
+			else
+				sdev->rmv_callback = 1;
 		}
 		dev->data->dev_conf.intr_conf.rmv = 0;
 		if (lsc_interrupt) {
@@ -156,6 +158,8 @@
 			if (ret)
 				WARN("Failed to register LSC callback for sub_device %d",
 				     SUB_ID(sdev));
+			else
+				sdev->lsc_callback = 1;
 		}
 		dev->data->dev_conf.intr_conf.lsc = lsc_enabled;
 		sdev->state = DEV_ACTIVE;
@@ -282,6 +286,7 @@
 	PRIV(dev)->state = DEV_ACTIVE - 1;
 	FOREACH_SUBDEV_STATE(sdev, i, dev, DEV_ACTIVE) {
 		DEBUG("Closing sub_device %d", i);
+		failsafe_eth_dev_unregister_callbacks(sdev);
 		rte_eth_dev_close(PORT_ID(sdev));
 		sdev->state = DEV_ACTIVE - 1;
 	}
diff --git a/drivers/net/failsafe/failsafe_private.h b/drivers/net/failsafe/failsafe_private.h
index 7e6a3f8..886af86 100644
--- a/drivers/net/failsafe/failsafe_private.h
+++ b/drivers/net/failsafe/failsafe_private.h
@@ -119,6 +119,10 @@ struct sub_device {
 	volatile unsigned int remove:1;
 	/* flow isolation state */
 	int flow_isolated:1;
+	/* RMV callback registration state */
+	unsigned int rmv_callback:1;
+	/* LSC callback registration state */
+	unsigned int lsc_callback:1;
 };
 
 struct fs_priv {
@@ -211,6 +215,7 @@ uint16_t failsafe_tx_burst_fast(void *txq,
 /* ETH_DEV */
 
 int failsafe_eth_dev_state_sync(struct rte_eth_dev *dev);
+void failsafe_eth_dev_unregister_callbacks(struct sub_device *sdev);
 void failsafe_dev_remove(struct rte_eth_dev *dev);
 void failsafe_stats_increment(struct rte_eth_stats *to,
 				struct rte_eth_stats *from);
-- 
1.9.5