Merge branch 'hinic-dev_get_stats-fixes'

Qiao Ma says:

====================
net: hinic: fix bugs about dev_get_stats

These patches fixes 2 bugs of hinic driver:
- fix bug that ethtool get wrong stats because of hinic_{txq|rxq}_clean_stats() is called
- avoid kernel hung in hinic_get_stats64()

See every patch for more information.

Changes in v4:
- removed meaningless u64_stats_sync protection in hinic_{txq|rxq}_get_stats
- merged the third patch in v2 into first one

Changes in v3:
- fixes a compile warning reported by kernel test robot <lkp@intel.com>

Changes in v2:
- fixes another 2 bugs. (v1 is a single patch, see: https://lore.kernel.org/all/07736c2b7019b6883076a06129e06e8f7c5f7154.1656487154.git.mqaio@linux.alibaba.com/).
- to fix extra bugs, hinic_dev.tx_stats/rx_stats is removed, so there is no need to use spinlock or semaphore now.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/huawei/hinic/hinic_dev.h

@@ -95,9 +95,6 @@ struct hinic_dev {
 	u16				sq_depth;
 	u16				rq_depth;
 
-	struct hinic_txq_stats          tx_stats;
-	struct hinic_rxq_stats          rx_stats;
-
 	u8				rss_tmpl_idx;
 	u8				rss_hash_engine;
 	u16				num_rss;

drivers/net/ethernet/huawei/hinic/hinic_main.c

@@ -80,56 +80,44 @@ static int set_features(struct hinic_dev *nic_dev,
 			netdev_features_t pre_features,
 			netdev_features_t features, bool force_change);
 
-static void update_rx_stats(struct hinic_dev *nic_dev, struct hinic_rxq *rxq)
+static void gather_rx_stats(struct hinic_rxq_stats *nic_rx_stats, struct hinic_rxq *rxq)
 {
-	struct hinic_rxq_stats *nic_rx_stats = &nic_dev->rx_stats;
 	struct hinic_rxq_stats rx_stats;
 
-	u64_stats_init(&rx_stats.syncp);
-
 	hinic_rxq_get_stats(rxq, &rx_stats);
 
-	u64_stats_update_begin(&nic_rx_stats->syncp);
 	nic_rx_stats->bytes += rx_stats.bytes;
 	nic_rx_stats->pkts  += rx_stats.pkts;
 	nic_rx_stats->errors += rx_stats.errors;
 	nic_rx_stats->csum_errors += rx_stats.csum_errors;
 	nic_rx_stats->other_errors += rx_stats.other_errors;
-	u64_stats_update_end(&nic_rx_stats->syncp);
-
-	hinic_rxq_clean_stats(rxq);
 }
 
-static void update_tx_stats(struct hinic_dev *nic_dev, struct hinic_txq *txq)
+static void gather_tx_stats(struct hinic_txq_stats *nic_tx_stats, struct hinic_txq *txq)
 {
-	struct hinic_txq_stats *nic_tx_stats = &nic_dev->tx_stats;
 	struct hinic_txq_stats tx_stats;
 
-	u64_stats_init(&tx_stats.syncp);
-
 	hinic_txq_get_stats(txq, &tx_stats);
 
-	u64_stats_update_begin(&nic_tx_stats->syncp);
 	nic_tx_stats->bytes += tx_stats.bytes;
 	nic_tx_stats->pkts += tx_stats.pkts;
 	nic_tx_stats->tx_busy += tx_stats.tx_busy;
 	nic_tx_stats->tx_wake += tx_stats.tx_wake;
 	nic_tx_stats->tx_dropped += tx_stats.tx_dropped;
 	nic_tx_stats->big_frags_pkts += tx_stats.big_frags_pkts;
-	u64_stats_update_end(&nic_tx_stats->syncp);
-
-	hinic_txq_clean_stats(txq);
 }
 
-static void update_nic_stats(struct hinic_dev *nic_dev)
+static void gather_nic_stats(struct hinic_dev *nic_dev,
+			     struct hinic_rxq_stats *nic_rx_stats,
+			     struct hinic_txq_stats *nic_tx_stats)
 {
 	int i, num_qps = hinic_hwdev_num_qps(nic_dev->hwdev);
 
 	for (i = 0; i < num_qps; i++)
-		update_rx_stats(nic_dev, &nic_dev->rxqs[i]);
+		gather_rx_stats(nic_rx_stats, &nic_dev->rxqs[i]);
 
 	for (i = 0; i < num_qps; i++)
-		update_tx_stats(nic_dev, &nic_dev->txqs[i]);
+		gather_tx_stats(nic_tx_stats, &nic_dev->txqs[i]);
 }
 
 /**
@@ -558,8 +546,6 @@ int hinic_close(struct net_device *netdev)
 	netif_carrier_off(netdev);
 	netif_tx_disable(netdev);
 
-	update_nic_stats(nic_dev);
-
 	up(&nic_dev->mgmt_lock);
 
 	if (!HINIC_IS_VF(nic_dev->hwdev->hwif))
@@ -853,26 +839,19 @@ static void hinic_get_stats64(struct net_device *netdev,
 			      struct rtnl_link_stats64 *stats)
 {
 	struct hinic_dev *nic_dev = netdev_priv(netdev);
-	struct hinic_rxq_stats *nic_rx_stats;
-	struct hinic_txq_stats *nic_tx_stats;
-
-	nic_rx_stats = &nic_dev->rx_stats;
-	nic_tx_stats = &nic_dev->tx_stats;
-
-	down(&nic_dev->mgmt_lock);
+	struct hinic_rxq_stats nic_rx_stats = {};
+	struct hinic_txq_stats nic_tx_stats = {};
 
 	if (nic_dev->flags & HINIC_INTF_UP)
-		update_nic_stats(nic_dev);
-
-	up(&nic_dev->mgmt_lock);
+		gather_nic_stats(nic_dev, &nic_rx_stats, &nic_tx_stats);
 
-	stats->rx_bytes   = nic_rx_stats->bytes;
-	stats->rx_packets = nic_rx_stats->pkts;
-	stats->rx_errors  = nic_rx_stats->errors;
+	stats->rx_bytes   = nic_rx_stats.bytes;
+	stats->rx_packets = nic_rx_stats.pkts;
+	stats->rx_errors  = nic_rx_stats.errors;
 
-	stats->tx_bytes   = nic_tx_stats->bytes;
-	stats->tx_packets = nic_tx_stats->pkts;
-	stats->tx_errors  = nic_tx_stats->tx_dropped;
+	stats->tx_bytes   = nic_tx_stats.bytes;
+	stats->tx_packets = nic_tx_stats.pkts;
+	stats->tx_errors  = nic_tx_stats.tx_dropped;
 }
 
 static int hinic_set_features(struct net_device *netdev,
@@ -1171,8 +1150,6 @@ static void hinic_free_intr_coalesce(struct hinic_dev *nic_dev)
 static int nic_dev_init(struct pci_dev *pdev)
 {
 	struct hinic_rx_mode_work *rx_mode_work;
-	struct hinic_txq_stats *tx_stats;
-	struct hinic_rxq_stats *rx_stats;
 	struct hinic_dev *nic_dev;
 	struct net_device *netdev;
 	struct hinic_hwdev *hwdev;
@@ -1234,12 +1211,6 @@ static int nic_dev_init(struct pci_dev *pdev)
 
 	sema_init(&nic_dev->mgmt_lock, 1);
 
-	tx_stats = &nic_dev->tx_stats;
-	rx_stats = &nic_dev->rx_stats;
-
-	u64_stats_init(&tx_stats->syncp);
-	u64_stats_init(&rx_stats->syncp);
-
 	nic_dev->vlan_bitmap = devm_bitmap_zalloc(&pdev->dev, VLAN_N_VID,
 						  GFP_KERNEL);
 	if (!nic_dev->vlan_bitmap) {

drivers/net/ethernet/huawei/hinic/hinic_rx.c

@@ -73,7 +73,6 @@ void hinic_rxq_get_stats(struct hinic_rxq *rxq, struct hinic_rxq_stats *stats)
 	struct hinic_rxq_stats *rxq_stats = &rxq->rxq_stats;
 	unsigned int start;
 
-	u64_stats_update_begin(&stats->syncp);
 	do {
 		start = u64_stats_fetch_begin(&rxq_stats->syncp);
 		stats->pkts = rxq_stats->pkts;
@@ -83,7 +82,6 @@ void hinic_rxq_get_stats(struct hinic_rxq *rxq, struct hinic_rxq_stats *stats)
 		stats->csum_errors = rxq_stats->csum_errors;
 		stats->other_errors = rxq_stats->other_errors;
 	} while (u64_stats_fetch_retry(&rxq_stats->syncp, start));
-	u64_stats_update_end(&stats->syncp);
 }
 
 /**

drivers/net/ethernet/huawei/hinic/hinic_tx.c

@@ -98,7 +98,6 @@ void hinic_txq_get_stats(struct hinic_txq *txq, struct hinic_txq_stats *stats)
 	struct hinic_txq_stats *txq_stats = &txq->txq_stats;
 	unsigned int start;
 
-	u64_stats_update_begin(&stats->syncp);
 	do {
 		start = u64_stats_fetch_begin(&txq_stats->syncp);
 		stats->pkts    = txq_stats->pkts;
@@ -108,7 +107,6 @@ void hinic_txq_get_stats(struct hinic_txq *txq, struct hinic_txq_stats *stats)
 		stats->tx_dropped = txq_stats->tx_dropped;
 		stats->big_frags_pkts = txq_stats->big_frags_pkts;
 	} while (u64_stats_fetch_retry(&txq_stats->syncp, start));
-	u64_stats_update_end(&stats->syncp);
 }
 
 /**