s390/qeth: remove prio-queueing support for z/VM NICs
authorJulian Wiedmann <jwi@linux.ibm.com>
Wed, 18 Mar 2020 12:54:47 +0000 (13:54 +0100)
committerDavid S. Miller <davem@davemloft.net>
Wed, 18 Mar 2020 23:33:35 +0000 (16:33 -0700)
z/VM NICs don't offer HW QoS for TX rings. So just use netdev_pick_tx()
to distribute the connections equally over all enabled TX queues.

We start with just 1 enabled TX queue (this matches the typical
configuration without prio-queueing). A follow-on patch will allow users
to enable additional TX queues.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/s390/net/qeth_core.h
drivers/s390/net/qeth_core_main.c
drivers/s390/net/qeth_core_sys.c
drivers/s390/net/qeth_l2_main.c
drivers/s390/net/qeth_l3_main.c

index 962be94..94cd396 100644 (file)
@@ -1053,6 +1053,7 @@ int qeth_configure_cq(struct qeth_card *, enum qeth_cq);
 int qeth_hw_trap(struct qeth_card *, enum qeth_diags_trap_action);
 void qeth_trace_features(struct qeth_card *);
 int qeth_setassparms_cb(struct qeth_card *, struct qeth_reply *, unsigned long);
+int qeth_setup_netdev(struct qeth_card *card);
 int qeth_set_features(struct net_device *, netdev_features_t);
 void qeth_enable_hw_features(struct net_device *dev);
 netdev_features_t qeth_fix_features(struct net_device *, netdev_features_t);
index 767cef0..f13495d 100644 (file)
@@ -1244,9 +1244,12 @@ EXPORT_SYMBOL_GPL(qeth_drain_output_queues);
 
 static int qeth_osa_set_output_queues(struct qeth_card *card, bool single)
 {
-       unsigned int count = single ? 1 : card->dev->num_tx_queues;
+       unsigned int max = single ? 1 : card->dev->num_tx_queues;
+       unsigned int count;
        int rc;
 
+       count = IS_VM_NIC(card) ? min(max, card->dev->real_num_tx_queues) : max;
+
        rtnl_lock();
        rc = netif_set_real_num_tx_queues(card->dev, count);
        rtnl_unlock();
@@ -1254,16 +1257,16 @@ static int qeth_osa_set_output_queues(struct qeth_card *card, bool single)
        if (rc)
                return rc;
 
-       if (card->qdio.no_out_queues == count)
+       if (card->qdio.no_out_queues == max)
                return 0;
 
        if (atomic_read(&card->qdio.state) != QETH_QDIO_UNINITIALIZED)
                qeth_free_qdio_queues(card);
 
-       if (count == 1)
+       if (max == 1 && card->qdio.do_prio_queueing != QETH_PRIOQ_DEFAULT)
                dev_info(&card->gdev->dev, "Priority Queueing not supported\n");
 
-       card->qdio.no_out_queues = count;
+       card->qdio.no_out_queues = max;
        return 0;
 }
 
@@ -5987,22 +5990,8 @@ static struct net_device *qeth_alloc_netdev(struct qeth_card *card)
        SET_NETDEV_DEV(dev, &card->gdev->dev);
        netif_carrier_off(dev);
 
-       if (IS_OSN(card)) {
-               dev->ethtool_ops = &qeth_osn_ethtool_ops;
-       } else {
-               dev->ethtool_ops = &qeth_ethtool_ops;
-               dev->priv_flags &= ~IFF_TX_SKB_SHARING;
-               dev->hw_features |= NETIF_F_SG;
-               dev->vlan_features |= NETIF_F_SG;
-               if (IS_IQD(card)) {
-                       dev->features |= NETIF_F_SG;
-                       if (netif_set_real_num_tx_queues(dev,
-                                                        QETH_IQD_MIN_TXQ)) {
-                               free_netdev(dev);
-                               return NULL;
-                       }
-               }
-       }
+       dev->ethtool_ops = IS_OSN(card) ? &qeth_osn_ethtool_ops :
+                                         &qeth_ethtool_ops;
 
        return dev;
 }
@@ -6018,6 +6007,28 @@ struct net_device *qeth_clone_netdev(struct net_device *orig)
        return clone;
 }
 
+int qeth_setup_netdev(struct qeth_card *card)
+{
+       struct net_device *dev = card->dev;
+       unsigned int num_tx_queues;
+
+       dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+       dev->hw_features |= NETIF_F_SG;
+       dev->vlan_features |= NETIF_F_SG;
+
+       if (IS_IQD(card)) {
+               dev->features |= NETIF_F_SG;
+               num_tx_queues = QETH_IQD_MIN_TXQ;
+       } else if (IS_VM_NIC(card)) {
+               num_tx_queues = 1;
+       } else {
+               num_tx_queues = dev->real_num_tx_queues;
+       }
+
+       return netif_set_real_num_tx_queues(dev, num_tx_queues);
+}
+EXPORT_SYMBOL_GPL(qeth_setup_netdev);
+
 static int qeth_core_probe_device(struct ccwgroup_device *gdev)
 {
        struct qeth_card *card;
@@ -6057,12 +6068,13 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
                goto err_card;
        }
 
+       qeth_determine_capabilities(card);
+       qeth_set_blkt_defaults(card);
+
        card->qdio.no_out_queues = card->dev->num_tx_queues;
        rc = qeth_update_from_chp_desc(card);
        if (rc)
                goto err_chp_desc;
-       qeth_determine_capabilities(card);
-       qeth_set_blkt_defaults(card);
 
        enforced_disc = qeth_enforce_discipline(card);
        switch (enforced_disc) {
index 78cae61..533a7f2 100644 (file)
@@ -176,7 +176,7 @@ static ssize_t qeth_dev_prioqing_store(struct device *dev,
        struct qeth_card *card = dev_get_drvdata(dev);
        int rc = 0;
 
-       if (IS_IQD(card))
+       if (IS_IQD(card) || IS_VM_NIC(card))
                return -EOPNOTSUPP;
 
        mutex_lock(&card->conf_mutex);
index 8ba4ac2..71eb2d9 100644 (file)
@@ -571,7 +571,9 @@ static u16 qeth_l2_select_queue(struct net_device *dev, struct sk_buff *skb,
                return qeth_iqd_select_queue(dev, skb,
                                             qeth_get_ether_cast_type(skb),
                                             sb_dev);
-       return qeth_get_priority_queue(card, skb);
+
+       return IS_VM_NIC(card) ? netdev_pick_tx(dev, skb, sb_dev) :
+                                qeth_get_priority_queue(card, skb);
 }
 
 static const struct device_type qeth_l2_devtype = {
@@ -659,6 +661,10 @@ static int qeth_l2_setup_netdev(struct qeth_card *card, bool carrier_ok)
                goto add_napi;
        }
 
+       rc = qeth_setup_netdev(card);
+       if (rc)
+               return rc;
+
        card->dev->needed_headroom = sizeof(struct qeth_hdr);
        card->dev->netdev_ops = &qeth_l2_netdev_ops;
        card->dev->priv_flags |= IFF_UNICAST_FLT;
index 8a803d6..81ec0d2 100644 (file)
@@ -1880,7 +1880,8 @@ static u16 qeth_l3_osa_select_queue(struct net_device *dev, struct sk_buff *skb,
 {
        struct qeth_card *card = dev->ml_priv;
 
-       return qeth_get_priority_queue(card, skb);
+       return IS_VM_NIC(card) ? netdev_pick_tx(dev, skb, sb_dev) :
+                                qeth_get_priority_queue(card, skb);
 }
 
 static const struct net_device_ops qeth_l3_netdev_ops = {
@@ -1922,6 +1923,10 @@ static int qeth_l3_setup_netdev(struct qeth_card *card, bool carrier_ok)
        unsigned int headroom;
        int rc;
 
+       rc = qeth_setup_netdev(card);
+       if (rc)
+               return rc;
+
        if (IS_OSD(card) || IS_OSX(card)) {
                if ((card->info.link_type == QETH_LINK_TYPE_LANE_TR) ||
                    (card->info.link_type == QETH_LINK_TYPE_HSTR)) {