ixgbe: Refactor MSI-X allocation mechanism

Our current MSI-X allocation mechanism does not support new hardware
at all.  It also isn't getting the actual number of supported MSI-X vectors
from the device.

This patch allows the number of MSI-X vectors to be specific to a device,
plus it gets the number of MSI-X vectors available from PCIe configuration
space.

Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 1 deletions

diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index 82afc606c238..7bbafa3ebbe3 100644
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c
@@ -2421,7 +2421,13 @@ static void ixgbe_acquire_msix_vectors(struct ixgbe_adapter *adapter,
                 ixgbe_set_num_queues(adapter);
         } else {
                 adapter->flags |= IXGBE_FLAG_MSIX_ENABLED; /* Woot! */
-                adapter->num_msix_vectors = vectors;
+                /*
+                 * Adjust for only the vectors we'll use, which is minimum
+                 * of max_msix_q_vectors + NON_Q_VECTORS, or the number of
+                 * vectors we were allocated.
+                 */
+                adapter->num_msix_vectors = min(vectors,
+                                   adapter->max_msix_q_vectors + NON_Q_VECTORS);
         }
 }
 
@@ -2746,6 +2752,7 @@ static int __devinit ixgbe_sw_init(struct ixgbe_adapter *adapter)
         adapter->ring_feature[RING_F_RSS].indices = rss;
         adapter->flags |= IXGBE_FLAG_RSS_ENABLED;
         adapter->ring_feature[RING_F_DCB].indices = IXGBE_MAX_DCB_INDICES;
+        adapter->max_msix_q_vectors = MAX_MSIX_Q_VECTORS_82598;
 
 #ifdef CONFIG_IXGBE_DCB
         /* Configure DCB traffic classes */