kmod-redhat-mlx5_core/SOURCES/0171-netdrv-net-mlx5e-Use-preactivate-hook-to-set-the-ind.patch

From c7e15c25bf93c8163905184c17829ac840677ab6 Mon Sep 17 00:00:00 2001
From: Alaa Hleihel <ahleihel@redhat.com>
Date: Tue, 12 May 2020 10:54:43 -0400
Subject: [PATCH 171/312] [netdrv] net/mlx5e: Use preactivate hook to set the
 indirection table

Message-id: <20200512105530.4207-78-ahleihel@redhat.com>
Patchwork-id: 306949
Patchwork-instance: patchwork
O-Subject: [RHEL8.3 BZ 1789382 077/124] net/mlx5e: Use preactivate hook to set the indirection table
Bugzilla: 1789382
RH-Acked-by: Tony Camuso <tcamuso@redhat.com>
RH-Acked-by: Kamal Heib <kheib@redhat.com>
RH-Acked-by: Jarod Wilson <jarod@redhat.com>

Bugzilla: http://bugzilla.redhat.com/1789382
Upstream: v5.7-rc1

commit fe867cac9e1967c553e4ac2aece5fc8675258010
Author: Maxim Mikityanskiy <maximmi@mellanox.com>
Date:   Mon Nov 4 12:02:14 2019 +0200

    net/mlx5e: Use preactivate hook to set the indirection table

    mlx5e_ethtool_set_channels updates the indirection table before
    switching to the new channels. If the switch fails, the indirection
    table is new, but the channels are old, which is wrong. Fix it by using
    the preactivate hook of mlx5e_safe_switch_channels to update the
    indirection table at the stage when nothing can fail anymore.

    As the code that updates the indirection table is now encapsulated into
    a new function, use that function in the attach flow when the driver has
    to reduce the number of channels, and prepare the code for the next
    commit.

    Fixes: 85082dba0a ("net/mlx5e: Correctly handle RSS indirection table when changing number of channels")
    Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
    Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
    Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Signed-off-by: Alaa Hleihel <ahleihel@redhat.com>
Signed-off-by: Frantisek Hrbata <fhrbata@redhat.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en.h         |  1 +
 drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c | 10 ++--------
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c    | 16 ++++++++++++++--
 3 files changed, 17 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 99c7a8047b26..cef4c1cba2b8 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -1032,6 +1032,7 @@ int mlx5e_safe_reopen_channels(struct mlx5e_priv *priv);
 int mlx5e_safe_switch_channels(struct mlx5e_priv *priv,
 			       struct mlx5e_channels *new_chs,
 			       mlx5e_fp_preactivate preactivate);
+int mlx5e_num_channels_changed(struct mlx5e_priv *priv);
 void mlx5e_activate_priv_channels(struct mlx5e_priv *priv);
 void mlx5e_deactivate_priv_channels(struct mlx5e_priv *priv);
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
index 70ca9bf51cdd..e7043f68a38f 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
@@ -432,9 +432,7 @@ int mlx5e_ethtool_set_channels(struct mlx5e_priv *priv,
 
 	if (!test_bit(MLX5E_STATE_OPENED, &priv->state)) {
 		*cur_params = new_channels.params;
-		if (!netif_is_rxfh_configured(priv->netdev))
-			mlx5e_build_default_indir_rqt(priv->rss_params.indirection_rqt,
-						      MLX5E_INDIR_RQT_SIZE, count);
+		mlx5e_num_channels_changed(priv);
 		goto out;
 	}
 
@@ -442,12 +440,8 @@ int mlx5e_ethtool_set_channels(struct mlx5e_priv *priv,
 	if (arfs_enabled)
 		mlx5e_arfs_disable(priv);
 
-	if (!netif_is_rxfh_configured(priv->netdev))
-		mlx5e_build_default_indir_rqt(priv->rss_params.indirection_rqt,
-					      MLX5E_INDIR_RQT_SIZE, count);
-
 	/* Switch to new channels, set new parameters and close old ones */
-	err = mlx5e_safe_switch_channels(priv, &new_channels, NULL);
+	err = mlx5e_safe_switch_channels(priv, &new_channels, mlx5e_num_channels_changed);
 
 	if (arfs_enabled) {
 		int err2 = mlx5e_arfs_enable(priv);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 70bcd75e241e..1d72ee543447 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -2898,6 +2898,17 @@ static void mlx5e_update_netdev_queues(struct mlx5e_priv *priv)
 	netif_set_real_num_rx_queues(netdev, num_rxqs);
 }
 
+int mlx5e_num_channels_changed(struct mlx5e_priv *priv)
+{
+	u16 count = priv->channels.params.num_channels;
+
+	if (!netif_is_rxfh_configured(priv->netdev))
+		mlx5e_build_default_indir_rqt(priv->rss_params.indirection_rqt,
+					      MLX5E_INDIR_RQT_SIZE, count);
+
+	return 0;
+}
+
 static void mlx5e_build_txq_maps(struct mlx5e_priv *priv)
 {
 	int i, ch;
@@ -5309,9 +5320,10 @@ int mlx5e_attach_netdev(struct mlx5e_priv *priv)
 	max_nch = mlx5e_get_max_num_channels(priv->mdev);
 	if (priv->channels.params.num_channels > max_nch) {
 		mlx5_core_warn(priv->mdev, "MLX5E: Reducing number of channels to %d\n", max_nch);
+		/* Reducing the number of channels - RXFH has to be reset. */
+		priv->netdev->priv_flags &= ~IFF_RXFH_CONFIGURED;
 		priv->channels.params.num_channels = max_nch;
-		mlx5e_build_default_indir_rqt(priv->rss_params.indirection_rqt,
-					      MLX5E_INDIR_RQT_SIZE, max_nch);
+		mlx5e_num_channels_changed(priv);
 	}
 
 	err = profile->init_tx(priv);
-- 
2.13.6