sfc: Make reset_workqueue driver-global rather than per-NIC

Each reset is serialised by the rtnl_lock anyway, so there's no win
per-NIC.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 20 insertions, 27 deletions

diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index bbc84026dd86..127b4da0a5e7 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -39,6 +39,12 @@
  */
 static struct workqueue_struct *refill_workqueue;
 
+/* Reset workqueue. If any NIC has a hardware failure then a reset will be
+ * queued onto this work queue. This is not a per-nic work queue, because
+ * efx_reset_work() acquires the rtnl lock, so resets are naturally serialised.
+ */
+static struct workqueue_struct *reset_workqueue;
+
 /**************************************************************************
  *
  * Configurable values
@@ -1697,7 +1703,7 @@ void efx_schedule_reset(struct efx_nic *efx, enum reset_type type)
 
         efx->reset_pending = method;
 
-        queue_work(efx->reset_workqueue, &efx->reset_work);
+        queue_work(reset_workqueue, &efx->reset_work);
 }
 
 /**************************************************************************
@@ -1763,7 +1769,7 @@ static int efx_init_struct(struct efx_nic *efx, struct efx_nic_type *type,
         struct efx_channel *channel;
         struct efx_tx_queue *tx_queue;
         struct efx_rx_queue *rx_queue;
-        int i, rc;
+        int i;
 
         /* Initialise common structures */
         memset(efx, 0, sizeof(*efx));
@@ -1832,33 +1838,14 @@ static int efx_init_struct(struct efx_nic *efx, struct efx_nic_type *type,
                                   interrupt_mode);
 
         efx->workqueue = create_singlethread_workqueue("sfc_work");
-        if (!efx->workqueue) {
-                rc = -ENOMEM;
-                goto fail1;
-        }
-
-        efx->reset_workqueue = create_singlethread_workqueue("sfc_reset");
-        if (!efx->reset_workqueue) {
-                rc = -ENOMEM;
-                goto fail2;
-        }
+        if (!efx->workqueue)
+                return -ENOMEM;
 
         return 0;
-
- fail2:
-        destroy_workqueue(efx->workqueue);
-        efx->workqueue = NULL;
-
- fail1:
-        return rc;
 }
 
 static void efx_fini_struct(struct efx_nic *efx)
 {
-        if (efx->reset_workqueue) {
-                destroy_workqueue(efx->reset_workqueue);
-                efx->reset_workqueue = NULL;
-        }
         if (efx->workqueue) {
                 destroy_workqueue(efx->workqueue);
                 efx->workqueue = NULL;
@@ -1923,7 +1910,7 @@ static void efx_pci_remove(struct pci_dev *pci_dev)
          * scheduled from this point because efx_stop_all() has been
          * called, we are no longer registered with driverlink, and
          * the net_device's have been removed. */
-        flush_workqueue(efx->reset_workqueue);
+        cancel_work_sync(&efx->reset_work);
 
         efx_pci_remove_main(efx);
 
@@ -2045,7 +2032,7 @@ static int __devinit efx_pci_probe(struct pci_dev *pci_dev,
                  * scheduled since efx_stop_all() has been called, and we
                  * have not and never have been registered with either
                  * the rtnetlink or driverlink layers. */
-                flush_workqueue(efx->reset_workqueue);
+                cancel_work_sync(&efx->reset_work);
 
                 /* Retry if a recoverably reset event has been scheduled */
                 if ((efx->reset_pending != RESET_TYPE_INVISIBLE) &&
@@ -2121,6 +2108,11 @@ static int __init efx_init_module(void)
                 rc = -ENOMEM;
                 goto err_refill;
         }
+        reset_workqueue = create_singlethread_workqueue("sfc_reset");
+        if (!reset_workqueue) {
+                rc = -ENOMEM;
+                goto err_reset;
+        }
 
         rc = pci_register_driver(&efx_pci_driver);
         if (rc < 0)
@@ -2129,6 +2121,8 @@ static int __init efx_init_module(void)
         return 0;
 
  err_pci:
+        destroy_workqueue(reset_workqueue);
+ err_reset:
         destroy_workqueue(refill_workqueue);
  err_refill:
         unregister_netdevice_notifier(&efx_netdev_notifier);
@@ -2141,6 +2135,7 @@ static void __exit efx_exit_module(void)
         printk(KERN_INFO "Solarflare NET driver unloading\n");
 
         pci_unregister_driver(&efx_pci_driver);
+        destroy_workqueue(reset_workqueue);
         destroy_workqueue(refill_workqueue);
         unregister_netdevice_notifier(&efx_netdev_notifier);
 
diff --git a/drivers/net/sfc/net_driver.h b/drivers/net/sfc/net_driver.h
index e596c9a6a4c4..f91060963475 100644
--- a/drivers/net/sfc/net_driver.h
+++ b/drivers/net/sfc/net_driver.h
@@ -635,7 +635,6 @@ union efx_multicast_hash {
  * @legacy_irq: IRQ number
  * @workqueue: Workqueue for port reconfigures and the HW monitor.
  *      Work items do not hold and must not acquire RTNL.
- * @reset_workqueue: Workqueue for resets.  Work item will acquire RTNL.
  * @reset_work: Scheduled reset workitem
  * @monitor_work: Hardware monitor workitem
  * @membase_phys: Memory BAR value as physical address
@@ -711,7 +710,6 @@ struct efx_nic {
         const struct efx_nic_type *type;
         int legacy_irq;
         struct workqueue_struct *workqueue;
-        struct workqueue_struct *reset_workqueue;
         struct work_struct reset_work;
         struct delayed_work monitor_work;
         resource_size_t membase_phys;