ixgbe: determine vector count inside ixgbe_acquire_msix_vectors

Our calculated v_budget doesn't matter except if we allocate MSI-X
vectors. We shouldn't need to calculate this outside of the function, so
don't. Instead, only calculate it once we attempt to acquire MSI-X
vectors. This helps collocate all of the MSI-X vector code together.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 37 insertions, 37 deletions

diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c
index f504fafa00bd..39df14f08aaa 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c
@@ -696,23 +696,45 @@ static void ixgbe_set_num_queues(struct ixgbe_adapter *adapter)
         ixgbe_set_rss_queues(adapter);
 }
 
-static int ixgbe_acquire_msix_vectors(struct ixgbe_adapter *adapter,
-                                      int vectors)
+/**
+ * ixgbe_acquire_msix_vectors - acquire MSI-X vectors
+ * @adapter: board private structure
+ *
+ * Attempts to acquire a suitable range of MSI-X vector interrupts. Will
+ * return a negative error code if unable to acquire MSI-X vectors for any
+ * reason.
+ */
+static int ixgbe_acquire_msix_vectors(struct ixgbe_adapter *adapter)
 {
-        int i, vector_threshold;
+        struct ixgbe_hw *hw = &adapter->hw;
+        int i, vectors, vector_threshold;
+
+        /* We start by asking for one vector per queue pair */
+        vectors = max(adapter->num_rx_queues, adapter->num_tx_queues);
 
-        /* We'll want at least 2 (vector_threshold):
-         * 1) TxQ[0] + RxQ[0] handler
-         * 2) Other (Link Status Change, etc.)
+        /* It is easy to be greedy for MSI-X vectors. However, it really
+         * doesn't do much good if we have a lot more vectors than CPUs. We'll
+         * be somewhat conservative and only ask for (roughly) the same number
+         * of vectors as there are CPUs.
          */
-        vector_threshold = MIN_MSIX_COUNT;
+        vectors = min_t(int, vectors, num_online_cpus());
 
-        /*
-         * The more we get, the more we will assign to Tx/Rx Cleanup
-         * for the separate queues...where Rx Cleanup >= Tx Cleanup.
-         * Right now, we simply care about how many we'll get; we'll
-         * set them up later while requesting irq's.
+        /* Some vectors are necessary for non-queue interrupts */
+        vectors += NON_Q_VECTORS;
+
+        /* Hardware can only support a maximum of hw.mac->max_msix_vectors.
+         * With features such as RSS and VMDq, we can easily surpass the
+         * number of Rx and Tx descriptor queues supported by our device.
+         * Thus, we cap the maximum in the rare cases where the CPU count also
+         * exceeds our vector limit
+         */
+        vectors = min_t(int, vectors, hw->mac.max_msix_vectors);
+
+        /* We want a minimum of two MSI-X vectors for (1) a TxQ[0] + RxQ[0]
+         * handler, and (2) an Other (Link Status Change, etc.) handler.
          */
+        vector_threshold = MIN_MSIX_COUNT;
+
         adapter->msix_entries = kcalloc(vectors,
                                         sizeof(struct msix_entry),
                                         GFP_KERNEL);
@@ -1069,32 +1091,10 @@ static void ixgbe_reset_interrupt_capability(struct ixgbe_adapter *adapter)
  **/
 static void ixgbe_set_interrupt_capability(struct ixgbe_adapter *adapter)
 {
-        struct ixgbe_hw *hw = &adapter->hw;
-        int v_budget, err;
-
-        /*
-         * It's easy to be greedy for MSI-X vectors, but it really
-         * doesn't do us much good if we have a lot more vectors
-         * than CPU's.  So let's be conservative and only ask for
-         * (roughly) the same number of vectors as there are CPU's.
-         * The default is to use pairs of vectors.
-         */
-        v_budget = max(adapter->num_rx_queues, adapter->num_tx_queues);
-        v_budget = min_t(int, v_budget, num_online_cpus());
-        v_budget += NON_Q_VECTORS;
-
-        /*
-         * At the same time, hardware can only support a maximum of
-         * hw.mac->max_msix_vectors vectors.  With features
-         * such as RSS and VMDq, we can easily surpass the number of Rx and Tx
-         * descriptor queues supported by our device.  Thus, we cap it off in
-         * those rare cases where the cpu count also exceeds our vector limit.
-         */
-        v_budget = min_t(int, v_budget, hw->mac.max_msix_vectors);
+        int err;
 
-        /* A failure in MSI-X entry allocation isn't fatal, but it does
-         * mean we disable MSI-X capabilities of the adapter. */
-        if (!ixgbe_acquire_msix_vectors(adapter, v_budget))
+        /* We will try to get MSI-X interrupts first */
+        if (!ixgbe_acquire_msix_vectors(adapter))
                 return;
 
         /* At this point, we do not have MSI-X capabilities. We need to