ehea: Update multiqueue support

The ehea driver had some multiqueue support but was missing the last
few years of networking stack improvements:

- Use skb_record_rx_queue to record which queue an skb came in on.

- Remove the driver specific netif_queue lock and use the networking
  stack transmit lock instead.

- Remove the driver specific transmit queue hashing and use
  skb_get_queue_mapping instead.

- Use netif_tx_{start|stop|wake}_queue where appropriate. We can also
  remove pr->queue_stopped and just check the queue status directly.

- Print all 16 queues in the ethtool stats.

We now enable multiqueue by default since it is a clear win on all my
testing so far.

v3:
[cascardo] fixed use_mcs parameter description
[cascardo] set ehea_ethtool_stats_keys as const

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 49 insertions, 62 deletions

diff --git a/drivers/net/ethernet/ibm/ehea/ehea.h b/drivers/net/ethernet/ibm/ehea/ehea.h
index 5b5c1b5ce31f..e247927139ba 100644
--- a/drivers/net/ethernet/ibm/ehea/ehea.h
+++ b/drivers/net/ethernet/ibm/ehea/ehea.h
@@ -375,8 +375,6 @@ struct ehea_port_res {
         struct ehea_q_skb_arr rq3_skba;
         struct ehea_q_skb_arr sq_skba;
         int sq_skba_size;
-        spinlock_t netif_queue;
-        int queue_stopped;
         int swqe_refill_th;
         atomic_t swqe_avail;
         int swqe_ll_count;
diff --git a/drivers/net/ethernet/ibm/ehea/ehea_ethtool.c b/drivers/net/ethernet/ibm/ehea/ehea_ethtool.c
index 7f642aef5e82..d185016c79ef 100644
--- a/drivers/net/ethernet/ibm/ehea/ehea_ethtool.c
+++ b/drivers/net/ethernet/ibm/ehea/ehea_ethtool.c
@@ -180,7 +180,7 @@ static void ehea_set_msglevel(struct net_device *dev, u32 value)
         port->msg_enable = value;
 }
 
-static char ehea_ethtool_stats_keys[][ETH_GSTRING_LEN] = {
+static const char ehea_ethtool_stats_keys[][ETH_GSTRING_LEN] = {
         {"sig_comp_iv"},
         {"swqe_refill_th"},
         {"port resets"},
@@ -189,7 +189,6 @@ static char ehea_ethtool_stats_keys[][ETH_GSTRING_LEN] = {
         {"IP cksum errors"},
         {"Frame cksum errors"},
         {"num SQ stopped"},
-        {"SQ stopped"},
         {"PR0 free_swqes"},
         {"PR1 free_swqes"},
         {"PR2 free_swqes"},
@@ -198,6 +197,14 @@ static char ehea_ethtool_stats_keys[][ETH_GSTRING_LEN] = {
         {"PR5 free_swqes"},
         {"PR6 free_swqes"},
         {"PR7 free_swqes"},
+        {"PR8 free_swqes"},
+        {"PR9 free_swqes"},
+        {"PR10 free_swqes"},
+        {"PR11 free_swqes"},
+        {"PR12 free_swqes"},
+        {"PR13 free_swqes"},
+        {"PR14 free_swqes"},
+        {"PR15 free_swqes"},
         {"LRO aggregated"},
         {"LRO flushed"},
         {"LRO no_desc"},
@@ -255,11 +262,7 @@ static void ehea_get_ethtool_stats(struct net_device *dev,
                 tmp += port->port_res[k].p_stats.queue_stopped;
         data[i++] = tmp;
 
-        for (k = 0, tmp = 0; k < EHEA_MAX_PORT_RES; k++)
-                tmp |= port->port_res[k].queue_stopped;
-        data[i++] = tmp;
-
-        for (k = 0; k < 8; k++)
+        for (k = 0; k < 16; k++)
                 data[i++] = atomic_read(&port->port_res[k].swqe_avail);
 
         for (k = 0, tmp = 0; k < EHEA_MAX_PORT_RES; k++)
diff --git a/drivers/net/ethernet/ibm/ehea/ehea_main.c b/drivers/net/ethernet/ibm/ehea/ehea_main.c
index ce9a67032724..a6c4192e12f4 100644
--- a/drivers/net/ethernet/ibm/ehea/ehea_main.c
+++ b/drivers/net/ethernet/ibm/ehea/ehea_main.c
@@ -61,7 +61,7 @@ static int rq1_entries = EHEA_DEF_ENTRIES_RQ1;
 static int rq2_entries = EHEA_DEF_ENTRIES_RQ2;
 static int rq3_entries = EHEA_DEF_ENTRIES_RQ3;
 static int sq_entries = EHEA_DEF_ENTRIES_SQ;
-static int use_mcs;
+static int use_mcs = 1;
 static int use_lro;
 static int lro_max_aggr = EHEA_LRO_MAX_AGGR;
 static int num_tx_qps = EHEA_NUM_TX_QP;
@@ -94,7 +94,8 @@ MODULE_PARM_DESC(rq1_entries, "Number of entries for Receive Queue 1 "
 MODULE_PARM_DESC(sq_entries, " Number of entries for the Send Queue  "
                  "[2^x - 1], x = [6..14]. Default = "
                  __MODULE_STRING(EHEA_DEF_ENTRIES_SQ) ")");
-MODULE_PARM_DESC(use_mcs, " 0:NAPI, 1:Multiple receive queues, Default = 0 ");
+MODULE_PARM_DESC(use_mcs, " Multiple receive queues, 1: enable, 0: disable, "
+                 "Default = 1");
 
 MODULE_PARM_DESC(lro_max_aggr, " LRO: Max packets to be aggregated. Default = "
                  __MODULE_STRING(EHEA_LRO_MAX_AGGR));
@@ -551,7 +552,8 @@ static inline int ehea_check_cqe(struct ehea_cqe *cqe, int *rq_num)
 }
 
 static inline void ehea_fill_skb(struct net_device *dev,
-                                 struct sk_buff *skb, struct ehea_cqe *cqe)
+                                 struct sk_buff *skb, struct ehea_cqe *cqe,
+                                 struct ehea_port_res *pr)
 {
         int length = cqe->num_bytes_transfered - 4;     /*remove CRC */
 
@@ -565,6 +567,8 @@ static inline void ehea_fill_skb(struct net_device *dev,
                 skb->csum = csum_unfold(~cqe->inet_checksum_value);
         } else
                 skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+        skb_record_rx_queue(skb, pr - &pr->port->port_res[0]);
 }
 
 static inline struct sk_buff *get_skb_by_index(struct sk_buff **skb_array,
@@ -750,7 +754,7 @@ static int ehea_proc_rwqes(struct net_device *dev,
                                 }
                                 skb_copy_to_linear_data(skb, ((char *)cqe) + 64,
                                                  cqe->num_bytes_transfered - 4);
-                                ehea_fill_skb(dev, skb, cqe);
+                                ehea_fill_skb(dev, skb, cqe, pr);
                         } else if (rq == 2) {
                                 /* RQ2 */
                                 skb = get_skb_by_index(skb_arr_rq2,
@@ -760,7 +764,7 @@ static int ehea_proc_rwqes(struct net_device *dev,
                                                   "rq2: skb=NULL\n");
                                         break;
                                 }
-                                ehea_fill_skb(dev, skb, cqe);
+                                ehea_fill_skb(dev, skb, cqe, pr);
                                 processed_rq2++;
                         } else {
                                 /* RQ3 */
@@ -771,7 +775,7 @@ static int ehea_proc_rwqes(struct net_device *dev,
                                                   "rq3: skb=NULL\n");
                                         break;
                                 }
-                                ehea_fill_skb(dev, skb, cqe);
+                                ehea_fill_skb(dev, skb, cqe, pr);
                                 processed_rq3++;
                         }
 
@@ -857,7 +861,8 @@ static struct ehea_cqe *ehea_proc_cqes(struct ehea_port_res *pr, int my_quota)
         int cqe_counter = 0;
         int swqe_av = 0;
         int index;
-        unsigned long flags;
+        struct netdev_queue *txq = netdev_get_tx_queue(pr->port->netdev,
+                                                pr - &pr->port->port_res[0]);
 
         cqe = ehea_poll_cq(send_cq);
         while (cqe && (quota > 0)) {
@@ -907,14 +912,15 @@ static struct ehea_cqe *ehea_proc_cqes(struct ehea_port_res *pr, int my_quota)
         ehea_update_feca(send_cq, cqe_counter);
         atomic_add(swqe_av, &pr->swqe_avail);
 
-        spin_lock_irqsave(&pr->netif_queue, flags);
-
-        if (pr->queue_stopped && (atomic_read(&pr->swqe_avail)
-                                  >= pr->swqe_refill_th)) {
-                netif_wake_queue(pr->port->netdev);
-                pr->queue_stopped = 0;
+        if (unlikely(netif_tx_queue_stopped(txq) &&
+                     (atomic_read(&pr->swqe_avail) >= pr->swqe_refill_th))) {
+                __netif_tx_lock(txq, smp_processor_id());
+                if (netif_tx_queue_stopped(txq) &&
+                    (atomic_read(&pr->swqe_avail) >= pr->swqe_refill_th))
+                        netif_tx_wake_queue(txq);
+                __netif_tx_unlock(txq);
         }
-        spin_unlock_irqrestore(&pr->netif_queue, flags);
+
         wake_up(&pr->port->swqe_avail_wq);
 
         return cqe;
@@ -1251,7 +1257,7 @@ static void ehea_parse_eqe(struct ehea_adapter *adapter, u64 eqe)
                                 netif_info(port, link, dev,
                                            "Logical port down\n");
                                 netif_carrier_off(dev);
-                                netif_stop_queue(dev);
+                                netif_tx_disable(dev);
                         }
 
                 if (EHEA_BMASK_GET(NEQE_EXTSWITCH_PORT_UP, eqe)) {
@@ -1282,7 +1288,7 @@ static void ehea_parse_eqe(struct ehea_adapter *adapter, u64 eqe)
         case EHEA_EC_PORT_MALFUNC:
                 netdev_info(dev, "Port malfunction\n");
                 netif_carrier_off(dev);
-                netif_stop_queue(dev);
+                netif_tx_disable(dev);
                 break;
         default:
                 netdev_err(dev, "unknown event code %x, eqe=0x%llX\n", ec, eqe);
@@ -1534,7 +1540,6 @@ static int ehea_init_port_res(struct ehea_port *port, struct ehea_port_res *pr,
         pr->rx_packets = rx_packets;
 
         pr->port = port;
-        spin_lock_init(&pr->netif_queue);
 
         pr->eq = ehea_create_eq(adapter, eq_type, EHEA_MAX_ENTRIES_EQ, 0);
         if (!pr->eq) {
@@ -2226,35 +2231,17 @@ static void ehea_xmit3(struct sk_buff *skb, struct net_device *dev,
         dev_kfree_skb(skb);
 }
 
-static inline int ehea_hash_skb(struct sk_buff *skb, int num_qps)
-{
-        struct tcphdr *tcp;
-        u32 tmp;
-
-        if ((skb->protocol == htons(ETH_P_IP)) &&
-            (ip_hdr(skb)->protocol == IPPROTO_TCP)) {
-                tcp = (struct tcphdr *)(skb_network_header(skb) +
-                                        (ip_hdr(skb)->ihl * 4));
-                tmp = (tcp->source + (tcp->dest << 16)) % 31;
-                tmp += ip_hdr(skb)->daddr % 31;
-                return tmp % num_qps;
-        } else
-                return 0;
-}
-
 static int ehea_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
         struct ehea_port *port = netdev_priv(dev);
         struct ehea_swqe *swqe;
-        unsigned long flags;
         u32 lkey;
         int swqe_index;
         struct ehea_port_res *pr;
+        struct netdev_queue *txq;
 
-        pr = &port->port_res[ehea_hash_skb(skb, port->num_tx_qps)];
-
-        if (pr->queue_stopped)
-                return NETDEV_TX_BUSY;
+        pr = &port->port_res[skb_get_queue_mapping(skb)];
+        txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
 
         swqe = ehea_get_swqe(pr->qp, &swqe_index);
         memset(swqe, 0, SWQE_HEADER_SIZE);
@@ -2304,20 +2291,15 @@ static int ehea_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 ehea_dump(swqe, 512, "swqe");
 
         if (unlikely(test_bit(__EHEA_STOP_XFER, &ehea_driver_flags))) {
-                netif_stop_queue(dev);
+                netif_tx_stop_queue(txq);
                 swqe->tx_control |= EHEA_SWQE_PURGE;
         }
 
         ehea_post_swqe(pr->qp, swqe);
 
         if (unlikely(atomic_read(&pr->swqe_avail) <= 1)) {
-                spin_lock_irqsave(&pr->netif_queue, flags);
-                if (unlikely(atomic_read(&pr->swqe_avail) <= 1)) {
-                        pr->p_stats.queue_stopped++;
-                        netif_stop_queue(dev);
-                        pr->queue_stopped = 1;
-                }
-                spin_unlock_irqrestore(&pr->netif_queue, flags);
+                pr->p_stats.queue_stopped++;
+                netif_tx_stop_queue(txq);
         }
 
         return NETDEV_TX_OK;
@@ -2642,7 +2624,7 @@ static int ehea_open(struct net_device *dev)
         ret = ehea_up(dev);
         if (!ret) {
                 port_napi_enable(port);
-                netif_start_queue(dev);
+                netif_tx_start_all_queues(dev);
         }
 
         mutex_unlock(&port->port_lock);
@@ -2688,7 +2670,7 @@ static int ehea_stop(struct net_device *dev)
         cancel_work_sync(&port->reset_task);
         cancel_delayed_work_sync(&port->stats_work);
         mutex_lock(&port->port_lock);
-        netif_stop_queue(dev);
+        netif_tx_stop_all_queues(dev);
         port_napi_disable(port);
         ret = ehea_down(dev);
         mutex_unlock(&port->port_lock);
@@ -2912,7 +2894,7 @@ static void ehea_reset_port(struct work_struct *work)
         mutex_lock(&dlpar_mem_lock);
         port->resets++;
         mutex_lock(&port->port_lock);
-        netif_stop_queue(dev);
+        netif_tx_disable(dev);
 
         port_napi_disable(port);
 
@@ -2928,7 +2910,7 @@ static void ehea_reset_port(struct work_struct *work)
 
         port_napi_enable(port);
 
-        netif_wake_queue(dev);
+        netif_tx_wake_all_queues(dev);
 out:
         mutex_unlock(&port->port_lock);
         mutex_unlock(&dlpar_mem_lock);
@@ -2955,7 +2937,7 @@ static void ehea_rereg_mrs(void)
 
                                 if (dev->flags & IFF_UP) {
                                         mutex_lock(&port->port_lock);
-                                        netif_stop_queue(dev);
+                                        netif_tx_disable(dev);
                                         ehea_flush_sq(port);
                                         ret = ehea_stop_qps(dev);
                                         if (ret) {
@@ -3000,7 +2982,7 @@ static void ehea_rereg_mrs(void)
                                                 if (!ret) {
                                                         check_sqs(port);
                                                         port_napi_enable(port);
-                                                        netif_wake_queue(dev);
+                                                        netif_tx_wake_all_queues(dev);
                                                 } else {
                                                         netdev_err(dev, "Unable to restart QPS\n");
                                                 }
@@ -3176,7 +3158,7 @@ struct ehea_port *ehea_setup_single_port(struct ehea_adapter *adapter,
         int jumbo;
 
         /* allocate memory for the port structures */
-        dev = alloc_etherdev(sizeof(struct ehea_port));
+        dev = alloc_etherdev_mq(sizeof(struct ehea_port), EHEA_MAX_PORT_RES);
 
         if (!dev) {
                 pr_err("no mem for net_device\n");
@@ -3208,6 +3190,10 @@ struct ehea_port *ehea_setup_single_port(struct ehea_adapter *adapter,
         if (ret)
                 goto out_free_mc_list;
 
+        netif_set_real_num_rx_queues(dev, port->num_def_qps);
+        netif_set_real_num_tx_queues(dev, port->num_def_qps +
+                                     port->num_add_tx_qps);
+
         port_dev = ehea_register_port(port, dn);
         if (!port_dev)
                 goto out_free_mc_list;