[dpdk-stable] patch 'net/ice: fix performance with writeback policy' has been queued to stable release 20.11.4

[Xueming Li]

Hi,

FYI, your patch has been queued to stable release 20.11.4

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 11/12/21. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/steevenlee/dpdk

This queued commit can be viewed at:
https://github.com/steevenlee/dpdk/commit/8404c8c99a31cd9d29761b3e29ba6f18d78746a6

Thanks.

Xueming Li <xuemingl at nvidia.com>

---
>From 8404c8c99a31cd9d29761b3e29ba6f18d78746a6 Mon Sep 17 00:00:00 2001
From: Qi Zhang <qi.z.zhang at intel.com>
Date: Sun, 29 Aug 2021 17:24:52 +0800
Subject: [PATCH] net/ice: fix performance with writeback policy
Cc: Xueming Li <xuemingl at nvidia.com>

[ upstream commit af167bcf174b59fa4776297e628a94143cf6a330 ]

Apply the same fix that for iavf to DCF
commit ead06572bd8f ("net/iavf: fix performance with writeback policy")

Fixes: 4b0d391f0eab ("net/ice: add queue config in DCF")

Signed-off-by: Qi Zhang <qi.z.zhang at intel.com>
Tested-by: Lijuan Tu <lijuan.tu at intel.com>
---
 drivers/net/ice/ice_dcf_ethdev.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ice/ice_dcf_ethdev.c b/drivers/net/ice/ice_dcf_ethdev.c
index 71f8a4b4cc..b523df47e1 100644
--- a/drivers/net/ice/ice_dcf_ethdev.c
+++ b/drivers/net/ice/ice_dcf_ethdev.c
@@ -166,10 +166,15 @@ ice_dcf_config_rx_queues_irqs(struct rte_eth_dev *dev,
 		    VIRTCHNL_VF_OFFLOAD_WB_ON_ITR) {
 			/* If WB_ON_ITR supports, enable it */
 			hw->msix_base = IAVF_RX_VEC_START;
+			/* Set the ITR for index zero, to 2us to make sure that
+			 * we leave time for aggregation to occur, but don't
+			 * increase latency dramatically.
+			 */
 			IAVF_WRITE_REG(&hw->avf,
 				       IAVF_VFINT_DYN_CTLN1(hw->msix_base - 1),
-				       IAVF_VFINT_DYN_CTLN1_ITR_INDX_MASK |
-				       IAVF_VFINT_DYN_CTLN1_WB_ON_ITR_MASK);
+				       (0 << IAVF_VFINT_DYN_CTLN1_ITR_INDX_SHIFT) |
+				       IAVF_VFINT_DYN_CTLN1_WB_ON_ITR_MASK |
+				       (2UL << IAVF_VFINT_DYN_CTLN1_INTERVAL_SHIFT));
 		} else {
 			/* If no WB_ON_ITR offload flags, need to set
 			 * interrupt for descriptor write back.
-- 
2.33.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2021-11-10 14:17:03.993573642 +0800
+++ 0042-net-ice-fix-performance-with-writeback-policy.patch	2021-11-10 14:17:01.797413358 +0800
@@ -1 +1 @@
-From af167bcf174b59fa4776297e628a94143cf6a330 Mon Sep 17 00:00:00 2001
+From 8404c8c99a31cd9d29761b3e29ba6f18d78746a6 Mon Sep 17 00:00:00 2001
@@ -4,0 +5,3 @@
+Cc: Xueming Li <xuemingl at nvidia.com>
+
+[ upstream commit af167bcf174b59fa4776297e628a94143cf6a330 ]
@@ -10 +12,0 @@
-Cc: stable at dpdk.org
@@ -19 +21 @@
-index 94c6a6e61c..f510bad381 100644
+index 71f8a4b4cc..b523df47e1 100644
@@ -22 +24 @@
-@@ -178,10 +178,15 @@ ice_dcf_config_rx_queues_irqs(struct rte_eth_dev *dev,
+@@ -166,10 +166,15 @@ ice_dcf_config_rx_queues_irqs(struct rte_eth_dev *dev,