ixgbe: add clean rx many routine

in some configurations there can be more than one rx queue per vector
in msi-x mode.  Add functionality to be able to clean this without
changing the performance path single-rx-queue cleanup.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 60 insertions, 2 deletions

diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index cde5d5a5a9ab..e18afa4e195f 100644
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c
@@ -1024,13 +1024,15 @@ static irqreturn_t ixgbe_msix_clean_many(int irq, void *data)
  * @napi: napi struct with our devices info in it
  * @budget: amount of work driver is allowed to do this pass, in packets
  *
+ * This function is optimized for cleaning one queue only on a single
+ * q_vector!!!
  **/
 static int ixgbe_clean_rxonly(struct napi_struct *napi, int budget)
 {
         struct ixgbe_q_vector *q_vector =
                                container_of(napi, struct ixgbe_q_vector, napi);
         struct ixgbe_adapter *adapter = q_vector->adapter;
-        struct ixgbe_ring *rx_ring;
+        struct ixgbe_ring *rx_ring = NULL;
         int work_done = 0;
         long r_idx;
 
@@ -1055,6 +1057,56 @@ static int ixgbe_clean_rxonly(struct napi_struct *napi, int budget)
         return work_done;
 }
 
+/**
+ * ixgbe_clean_rxonly_many - msix (aka one shot) rx clean routine
+ * @napi: napi struct with our devices info in it
+ * @budget: amount of work driver is allowed to do this pass, in packets
+ *
+ * This function will clean more than one rx queue associated with a
+ * q_vector.
+ **/
+static int ixgbe_clean_rxonly_many(struct napi_struct *napi, int budget)
+{
+        struct ixgbe_q_vector *q_vector =
+                               container_of(napi, struct ixgbe_q_vector, napi);
+        struct ixgbe_adapter *adapter = q_vector->adapter;
+        struct net_device *netdev = adapter->netdev;
+        struct ixgbe_ring *rx_ring = NULL;
+        int work_done = 0, i;
+        long r_idx;
+        u16 enable_mask = 0;
+
+        /* attempt to distribute budget to each queue fairly, but don't allow
+         * the budget to go below 1 because we'll exit polling */
+        budget /= (q_vector->rxr_count ?: 1);
+        budget = max(budget, 1);
+        r_idx = find_first_bit(q_vector->rxr_idx, adapter->num_rx_queues);
+        for (i = 0; i < q_vector->rxr_count; i++) {
+                rx_ring = &(adapter->rx_ring[r_idx]);
+#if defined(CONFIG_DCA) || defined(CONFIG_DCA_MODULE)
+                if (adapter->flags & IXGBE_FLAG_DCA_ENABLED)
+                        ixgbe_update_rx_dca(adapter, rx_ring);
+#endif
+                ixgbe_clean_rx_irq(adapter, rx_ring, &work_done, budget);
+                enable_mask |= rx_ring->v_idx;
+                r_idx = find_next_bit(q_vector->rxr_idx, adapter->num_rx_queues,
+                                      r_idx + 1);
+        }
+
+        r_idx = find_first_bit(q_vector->rxr_idx, adapter->num_rx_queues);
+        rx_ring = &(adapter->rx_ring[r_idx]);
+        /* If all Rx work done, exit the polling mode */
+        if ((work_done == 0) || !netif_running(netdev)) {
+                netif_rx_complete(netdev, napi);
+                if (adapter->itr_setting & 3)
+                        ixgbe_set_itr_msix(q_vector);
+                if (!test_bit(__IXGBE_DOWN, &adapter->state))
+                        IXGBE_WRITE_REG(&adapter->hw, IXGBE_EIMS, enable_mask);
+                return 0;
+        }
+
+        return work_done;
+}
 static inline void map_vector_to_rxq(struct ixgbe_adapter *a, int v_idx,
                                      int r_idx)
 {
@@ -1813,10 +1865,16 @@ static void ixgbe_napi_enable_all(struct ixgbe_adapter *adapter)
                 q_vectors = 1;
 
         for (q_idx = 0; q_idx < q_vectors; q_idx++) {
+                struct napi_struct *napi;
                 q_vector = &adapter->q_vector[q_idx];
                 if (!q_vector->rxr_count)
                         continue;
-                napi_enable(&q_vector->napi);
+                napi = &q_vector->napi;
+                if ((adapter->flags & IXGBE_FLAG_MSIX_ENABLED) &&
+                    (q_vector->rxr_count > 1))
+                        napi->poll = &ixgbe_clean_rxonly_many;
+
+                napi_enable(napi);
         }
 }