[dpdk-dev] [PATCH] net/ixgbe: keep interrupt throttling disabled

[David Su <david.w.su@intel.com>]

The code being removed would enable time-based interrupt throttling for
the first MSI-X interrupt vector.  This would throttle link status
change interrupts for NICs bound to vfio_pci driver; but for
igb_uio driver, rx queue 0 interrupts would be throttled.  This resulted
in inconsistent latencies in a DPDK interrupt mode packet forwarding
application between the 2 drivers.

We'd like DPDK interrupt mode applications to be awaken by
inbound packet interrupts as soon as they are received regardless
of interrupt interval, interrupt throttling should be kept disabled.

Signed-off-by: David Su <david.w.su@intel.com>
---
 drivers/net/ixgbe/ixgbe_ethdev.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index bdf4e2b..fdfb7a6 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -5815,8 +5815,6 @@ ixgbe_configure_msix(struct rte_eth_dev *dev)
 	default:
 		break;
 	}
-	IXGBE_WRITE_REG(hw, IXGBE_EITR(IXGBE_MISC_VEC_ID),
-			IXGBE_MIN_INTER_INTERRUPT_INTERVAL_DEFAULT & 0xFFF);
 
 	/* set up to autoclear timer, and the vectors */
 	mask = IXGBE_EIMS_ENABLE_MASK;
-- 
1.7.0.4