[PATCH RFC 40/77] ixgbevf: Update MSI/MSI-X interrupts enablement code

[Alexander Gordeev]

As result of recent re-design of the MSI/MSI-X interrupts enabling
pattern this driver has to be updated to use the new technique to
obtain a optimal number of MSI/MSI-X interrupts required.

Signed-off-by: Alexander Gordeev <agordeev at redhat.com>
---
 drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c |   18 +++++++-----------
 1 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index fa0537a..d506a01 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -1749,8 +1749,7 @@ void ixgbevf_reset(struct ixgbevf_adapter *adapter)
 static int ixgbevf_acquire_msix_vectors(struct ixgbevf_adapter *adapter,
 					int vectors)
 {
-	int err = 0;
-	int vector_threshold;
+	int err, vector_threshold;
 
 	/* We'll want at least 2 (vector_threshold):
 	 * 1) TxQ[0] + RxQ[0] handler
@@ -1763,18 +1762,15 @@ static int ixgbevf_acquire_msix_vectors(struct ixgbevf_adapter *adapter,
 	 * Right now, we simply care about how many we'll get; we'll
 	 * set them up later while requesting irq's.
 	 */
-	while (vectors >= vector_threshold) {
-		err = pci_enable_msix(adapter->pdev, adapter->msix_entries,
-				      vectors);
-		if (!err || err < 0) /* Success or a nasty failure. */
-			break;
-		else /* err == number of vectors we should try again with */
-			vectors = err;
-	}
+	err = pci_msix_table_size(adapter->pdev);
+	if (err < 0)
+		return err;
 
+	vectors = min(vectors, err);
 	if (vectors < vector_threshold)
-		err = -ENOSPC;
+		return -ENOSPC;
 
+	err = pci_enable_msix(adapter->pdev, adapter->msix_entries, vectors);
 	if (err) {
 		dev_err(&adapter->pdev->dev,
 			"Unable to allocate MSI-X interrupts\n");
-- 
1.7.7.6