[PATCH 4/4] net/ixgbevf: add check for rte_intr_enable.

[xiangxia.m.yue@gmail.com]

From: Tonghao Zhang <zhangtonghao@didichuxing.com>

When we bind the ixgbevf to vfio and call the rte_eth_dev_rx_intr_enable
and rte_eth_dev_rx_intr_disable frequently, the interrupt setting
(msi_set_mask_bit) will take more CPU as show below. rte_intr_enable
call the ioctl to map the fd to interrupts frequently.

perf top:
5.45%  [kernel]   [k] msi_set_mask_bit

It is unnecessary to call the rte_intr_enable in ixgbe_dev_rx_queue_intr_enable.
because the fds has been mapped to interrupt and not unmapped in
ixgbe_dev_rx_queue_intr_disable.

This patch add checks for using VFIO.  With the patch, msi_set_mask_bit is not listed
in perl any more. Any suggestion will be welcome.

Signed-off-by: Tonghao Zhang <zhangtonghao@didichuxing.com>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
---
 drivers/net/ixgbe/ixgbe_ethdev.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index f534f20..b958734 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -5631,7 +5631,9 @@ static void ixgbevf_set_vfta_all(struct rte_eth_dev *dev, bool on)
 	RTE_SET_USED(queue_id);
 	IXGBE_WRITE_REG(hw, IXGBE_VTEIMS, intr->mask);
 
-	rte_intr_enable(intr_handle);
+	if (intr_handle->type == RTE_INTR_HANDLE_UIO ||
+	    intr_handle->type == RTE_INTR_HANDLE_UIO_INTX)
+		rte_intr_enable(intr_handle);
 
 	return 0;
 }
@@ -5680,7 +5682,10 @@ static void ixgbevf_set_vfta_all(struct rte_eth_dev *dev, bool on)
 		mask &= (1 << (queue_id - 32));
 		IXGBE_WRITE_REG(hw, IXGBE_EIMS_EX(1), mask);
 	}
-	rte_intr_enable(intr_handle);
+	
+	if (intr_handle->type == RTE_INTR_HANDLE_UIO ||
+	    intr_handle->type == RTE_INTR_HANDLE_UIO_INTX)
+		rte_intr_enable(intr_handle);
 
 	return 0;
 }
-- 
1.8.3.1