igb: only support SRRCTL_DROP_EN when using multiple queues
The SRRCTL.DROP_EN bit should only be set when we are supporting
multiple queues. This bit is meant to prevent head of line blocking
and is unnecessary in the single queue case.
Signed-off-by: Nicholas Nunley <nicholasx.d.nunley@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c
index 4ccc7fc..b989b34 100644
--- a/drivers/net/igb/igb_main.c
+++ b/drivers/net/igb/igb_main.c
@@ -2595,6 +2595,9 @@
E1000_SRRCTL_BSIZEPKT_SHIFT;
srrctl |= E1000_SRRCTL_DESCTYPE_ADV_ONEBUF;
}
+ /* Only set Drop Enable if we are supporting multiple queues */
+ if (adapter->vfs_allocated_count || adapter->num_rx_queues > 1)
+ srrctl |= E1000_SRRCTL_DROP_EN;
wr32(E1000_SRRCTL(reg_idx), srrctl);