[dpdk-stable] [PATCH] net/ixgbe: fix blocked interrupts

[Qi Zhang <qi.z.zhang@intel.com>]

[ backported from upstream commit 9b667210700e6b52a123cc5b36d0a3b0b3aa7c94 ]

While handling link status change (LSC) interrupt, all interrupts are
blocked until delayed interrupt handler finishes.
The wait duration is at least one second and this may cause timeouts in
VF to PF mailbox.
Make sure only LSC interrupt is blocked while waiting for delayed
interrupt handler to finish.

Fixes: 0a45657a6794 ("pci: rework interrupt handling")

Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
---
 drivers/net/ixgbe/ixgbe_ethdev.c | 18 ++++++++----------
 drivers/net/ixgbe/ixgbe_ethdev.h |  2 ++
 2 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index dbfb0c0..bac36e0 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -3474,7 +3474,6 @@ ixgbe_dev_interrupt_action(struct rte_eth_dev *dev)
 		IXGBE_DEV_PRIVATE_TO_INTR(dev->data->dev_private);
 	int64_t timeout;
 	struct rte_eth_link link;
-	int intr_enable_delay = false;
 	struct ixgbe_hw *hw =
 		IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
 
@@ -3507,20 +3506,19 @@ ixgbe_dev_interrupt_action(struct rte_eth_dev *dev)
 			timeout = IXGBE_LINK_DOWN_CHECK_TIMEOUT;
 
 		ixgbe_dev_link_status_print(dev);
-
-		intr_enable_delay = true;
-	}
-
-	if (intr_enable_delay) {
+		intr->mask_original = intr->mask;
+		/* only disable lsc interrupt */
+		intr->mask &= ~IXGBE_EIMS_LSC;
 		if (rte_eal_alarm_set(timeout * 1000,
 				      ixgbe_dev_interrupt_delayed_handler, (void *)dev) < 0)
 			PMD_DRV_LOG(ERR, "Error setting alarm");
-	} else {
-		PMD_DRV_LOG(DEBUG, "enable intr immediately");
-		ixgbe_enable_intr(dev);
-		rte_intr_enable(&(dev->pci_dev->intr_handle));
+		else
+			intr->mask = intr->mask_original;
 	}
 
+	PMD_DRV_LOG(DEBUG, "enable intr immediately");
+	ixgbe_enable_intr(dev);
+	rte_intr_enable(&dev->pci_dev->intr_handle);
 
 	return 0;
 }
diff --git a/drivers/net/ixgbe/ixgbe_ethdev.h b/drivers/net/ixgbe/ixgbe_ethdev.h
index 4ff6338..a4e2996 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.h
+++ b/drivers/net/ixgbe/ixgbe_ethdev.h
@@ -165,6 +165,8 @@ struct ixgbe_hw_fdir_info {
 struct ixgbe_interrupt {
 	uint32_t flags;
 	uint32_t mask;
+	/*to save original mask during delayed handler */
+	uint32_t mask_original;
 };
 
 struct ixgbe_stat_mapping_registers {
-- 
2.7.4