netdev - [PATCH v3 bpf-next 01/11] ice: compress branches in ice_set

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Message-Id: <20220615161041.902916-2-maciej.fijalkowski@intel.com>
Date:   Wed, 15 Jun 2022 18:10:31 +0200
From:   Maciej Fijalkowski <maciej.fijalkowski@...el.com>
To:     bpf@...r.kernel.org, ast@...nel.org, daniel@...earbox.net
Cc:     netdev@...r.kernel.org, magnus.karlsson@...el.com,
        bjorn@...nel.org,
        Maciej Fijalkowski <maciej.fijalkowski@...el.com>,
        Alexandr Lobakin <alexandr.lobakin@...el.com>
Subject: [PATCH v3 bpf-next 01/11] ice: compress branches in ice_set_features()

Instead of rather verbose comparison of current netdev->features bits vs
the incoming ones from user, let us compress them by a helper features
set that will be the result of netdev->features XOR features. This way,
current, extensive branches:

	if (features & NETIF_F_BIT && !(netdev->features & NETIF_F_BIT))
		set_feature(true);
	else if (!(features & NETIF_F_BIT) && netdev->features & NETIF_F_BIT)
		set_feature(false);

can become:

	netdev_features_t changed = netdev->features ^ features;

	if (changed & NETIF_F_BIT)
		set_feature(!!(features & NETIF_F_BIT));

This is nothing new as currently several other drivers use this
approach, which I find much more convenient.

CC: Alexandr Lobakin <alexandr.lobakin@...el.com>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@...el.com>
---
 drivers/net/ethernet/intel/ice/ice_main.c | 40 +++++++++++------------
 1 file changed, 19 insertions(+), 21 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_main.c b/drivers/net/ethernet/intel/ice/ice_main.c
index e1cae253412c..23d1b1fc39fb 100644
--- a/drivers/net/ethernet/intel/ice/ice_main.c
+++ b/drivers/net/ethernet/intel/ice/ice_main.c
@@ -5910,44 +5910,41 @@ ice_set_vlan_features(struct net_device *netdev, netdev_features_t features)
 static int
 ice_set_features(struct net_device *netdev, netdev_features_t features)
 {
+	netdev_features_t changed = netdev->features ^ features;
 	struct ice_netdev_priv *np = netdev_priv(netdev);
 	struct ice_vsi *vsi = np->vsi;
 	struct ice_pf *pf = vsi->back;
 	int ret = 0;
 
 	/* Don't set any netdev advanced features with device in Safe Mode */
-	if (ice_is_safe_mode(vsi->back)) {
-		dev_err(ice_pf_to_dev(vsi->back), "Device is in Safe Mode - not enabling advanced netdev features\n");
+	if (ice_is_safe_mode(pf)) {
+		dev_err(ice_pf_to_dev(vsi->back),
+			"Device is in Safe Mode - not enabling advanced netdev features\n");
 		return ret;
 	}
 
 	/* Do not change setting during reset */
 	if (ice_is_reset_in_progress(pf->state)) {
-		dev_err(ice_pf_to_dev(vsi->back), "Device is resetting, changing advanced netdev features temporarily unavailable.\n");
+		dev_err(ice_pf_to_dev(pf),
+			"Device is resetting, changing advanced netdev features temporarily unavailable.\n");
 		return -EBUSY;
 	}
 
 	/* Multiple features can be changed in one call so keep features in
 	 * separate if/else statements to guarantee each feature is checked
 	 */
-	if (features & NETIF_F_RXHASH && !(netdev->features & NETIF_F_RXHASH))
-		ice_vsi_manage_rss_lut(vsi, true);
-	else if (!(features & NETIF_F_RXHASH) &&
-		 netdev->features & NETIF_F_RXHASH)
-		ice_vsi_manage_rss_lut(vsi, false);
+	if (changed & NETIF_F_RXHASH)
+		ice_vsi_manage_rss_lut(vsi, !!(features & NETIF_F_RXHASH));
 
 	ret = ice_set_vlan_features(netdev, features);
 	if (ret)
 		return ret;
 
-	if ((features & NETIF_F_NTUPLE) &&
-	    !(netdev->features & NETIF_F_NTUPLE)) {
-		ice_vsi_manage_fdir(vsi, true);
-		ice_init_arfs(vsi);
-	} else if (!(features & NETIF_F_NTUPLE) &&
-		 (netdev->features & NETIF_F_NTUPLE)) {
-		ice_vsi_manage_fdir(vsi, false);
-		ice_clear_arfs(vsi);
+	if (changed & NETIF_F_NTUPLE) {
+		bool ena = !!(features & NETIF_F_NTUPLE);
+
+		ice_vsi_manage_fdir(vsi, ena);
+		ena ? ice_init_arfs(vsi) : ice_clear_arfs(vsi);
 	}
 
 	/* don't turn off hw_tc_offload when ADQ is already enabled */
@@ -5956,11 +5953,12 @@ ice_set_features(struct net_device *netdev, netdev_features_t features)
 		return -EACCES;
 	}
 
-	if ((features & NETIF_F_HW_TC) &&
-	    !(netdev->features & NETIF_F_HW_TC))
-		set_bit(ICE_FLAG_CLS_FLOWER, pf->flags);
-	else
-		clear_bit(ICE_FLAG_CLS_FLOWER, pf->flags);
+	if (changed & NETIF_F_HW_TC) {
+		bool ena = !!(features & NETIF_F_HW_TC);
+
+		ena ? set_bit(ICE_FLAG_CLS_FLOWER, pf->flags) :
+		      clear_bit(ICE_FLAG_CLS_FLOWER, pf->flags);
+	}
 
 	return 0;
 }
-- 
2.27.0