[dpdk-dev] [PATCH net-next v4 1/4] net/ixgbevf: set the interrupt interval for EITR

[xiangxia.m.yue@gmail.com]

From: Tonghao Zhang <xiangxia.m.yue@gmail.com>

Set EITR interval as default. This patch can improve the
performance when we enable the rx-interrupt to process the
packets because we hope rx-interrupt reduce CPU. For example,
the 200us value of EITR makes the performance better with
the low CPU. The default value of ITR is 500us, compatible
with RSC of ixgbe PF, and next patch will use the default value.

Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
---
 drivers/net/ixgbe/ixgbe_ethdev.c | 7 +++++++
 drivers/net/ixgbe/ixgbe_ethdev.h | 1 +
 2 files changed, 8 insertions(+)

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index 6088c7e..bdede8b 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -5803,6 +5803,13 @@ static void ixgbevf_set_vfta_all(struct rte_eth_dev *dev, bool on)
 		if (vector_idx < base + intr_handle->nb_efd - 1)
 			vector_idx++;
 	}
+
+	/* As RX queue setting above show, all queues use the vector 0.
+	 * Set only the ITR value of IXGBE_MISC_VEC_ID.
+	 */
+	IXGBE_WRITE_REG(hw, IXGBE_VTEITR(IXGBE_MISC_VEC_ID),
+			IXGBE_EITR_INTERVAL_US(IXGBE_QUEUE_ITR_INTERVAL_DEFAULT)
+			| IXGBE_EITR_CNT_WDIS);
 }
 
 /**
diff --git a/drivers/net/ixgbe/ixgbe_ethdev.h b/drivers/net/ixgbe/ixgbe_ethdev.h
index cc512d6..e42ec30 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.h
+++ b/drivers/net/ixgbe/ixgbe_ethdev.h
@@ -62,6 +62,7 @@
 	(((us) * 1000 / IXGBE_EITR_INTERVAL_UNIT_NS << IXGBE_EITR_ITR_INT_SHIFT) & \
 		IXGBE_EITR_ITR_INT_MASK)
 
+#define IXGBE_QUEUE_ITR_INTERVAL_DEFAULT	500 /* 500us */
 
 /* Loopback operation modes */
 /* 82599 specific loopback operation types */
-- 
1.8.3.1