[dpdk-stable] patch 'net/mlx5: do not select legacy MPW implicitly' has been queued to stable release 19.11.4

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 19.11.4

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 07/26/20. 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.

Thanks.

Luca Boccassi

---
>From f0ba791d7bafa43caecac02748cb655529633c63 Mon Sep 17 00:00:00 2001
From: Alexander Kozyrev <akozyrev at mellanox.com>
Date: Thu, 11 Jun 2020 17:42:00 +0000
Subject: [PATCH] net/mlx5: do not select legacy MPW implicitly

[ upstream commit a23d96ae59e21f7b0ada43d2757a726fc565005a ]

The Legacy MPW (multi-packet write) should not be engaged implicitly.
We should exclude this function from a Tx burst routine selection
process unless it is requested specifically by setting the txq_mpw_en
devarg.  Exclude this function from the selection process the same way
it is done for the Enhanced MPW in the mlx5_select_tx_function()
routine.

Fixes: eb8121ab9dac ("net/mlx5: introduce Tx burst routine template")

Signed-off-by: Alexander Kozyrev <akozyrev at mellanox.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>
---
 drivers/net/mlx5/mlx5_rxtx.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
index 488a87f59..90625e71f 100644
--- a/drivers/net/mlx5/mlx5_rxtx.c
+++ b/drivers/net/mlx5/mlx5_rxtx.c
@@ -5365,6 +5365,9 @@ mlx5_select_tx_function(struct rte_eth_dev *dev)
 			/* Does not meet requested offloads at all. */
 			continue;
 		}
+		if ((olx ^ tmp) & MLX5_TXOFF_CONFIG_MPW)
+			/* Do not enable legacy MPW if not configured. */
+			continue;
 		if ((olx ^ tmp) & MLX5_TXOFF_CONFIG_EMPW)
 			/* Do not enable eMPW if not configured. */
 			continue;
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2020-07-24 12:53:49.835804063 +0100
+++ 0032-net-mlx5-do-not-select-legacy-MPW-implicitly.patch	2020-07-24 12:53:48.223005267 +0100
@@ -1,8 +1,10 @@
-From a23d96ae59e21f7b0ada43d2757a726fc565005a Mon Sep 17 00:00:00 2001
+From f0ba791d7bafa43caecac02748cb655529633c63 Mon Sep 17 00:00:00 2001
 From: Alexander Kozyrev <akozyrev at mellanox.com>
 Date: Thu, 11 Jun 2020 17:42:00 +0000
 Subject: [PATCH] net/mlx5: do not select legacy MPW implicitly
 
+[ upstream commit a23d96ae59e21f7b0ada43d2757a726fc565005a ]
+
 The Legacy MPW (multi-packet write) should not be engaged implicitly.
 We should exclude this function from a Tx burst routine selection
 process unless it is requested specifically by setting the txq_mpw_en
@@ -11,7 +13,6 @@
 routine.
 
 Fixes: eb8121ab9dac ("net/mlx5: introduce Tx burst routine template")
-Cc: stable at dpdk.org
 
 Signed-off-by: Alexander Kozyrev <akozyrev at mellanox.com>
 Acked-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>
@@ -20,10 +21,10 @@
  1 file changed, 3 insertions(+)
 
 diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
-index 22cdf1518..4d67925e5 100644
+index 488a87f59..90625e71f 100644
 --- a/drivers/net/mlx5/mlx5_rxtx.c
 +++ b/drivers/net/mlx5/mlx5_rxtx.c
-@@ -5542,6 +5542,9 @@ mlx5_select_tx_function(struct rte_eth_dev *dev)
+@@ -5365,6 +5365,9 @@ mlx5_select_tx_function(struct rte_eth_dev *dev)
  			/* Does not meet requested offloads at all. */
  			continue;
  		}