svn commit: r252715 - head/sys/dev/cxgbe

[Navdeep Parhar]

Author: np
Date: Thu Jul  4 19:15:41 2013
New Revision: 252715
URL: http://svnweb.freebsd.org/changeset/base/252715

Log:
  Ring the egress queue's doorbell as soon as there are 8 or more
  descriptors ready to be processed.
  
  MFC after:	1 day

Modified:
  head/sys/dev/cxgbe/t4_sge.c

Modified: head/sys/dev/cxgbe/t4_sge.c
==============================================================================
--- head/sys/dev/cxgbe/t4_sge.c	Thu Jul  4 19:01:18 2013	(r252714)
+++ head/sys/dev/cxgbe/t4_sge.c	Thu Jul  4 19:15:41 2013	(r252715)
@@ -1337,7 +1337,7 @@ t4_wrq_tx_locked(struct adapter *sc, str
 			eq->pidx -= eq->cap;
 
 		eq->pending += ndesc;
-		if (eq->pending > 16)
+		if (eq->pending >= 8)
 			ring_eq_db(sc, eq);
 
 		wrq->tx_wrs++;
@@ -1508,8 +1508,8 @@ t4_eth_tx(struct ifnet *ifp, struct sge_
 		if (sgl.nsegs == 0)
 			m_freem(m);
 doorbell:
-		if (eq->pending >= 64)
-		    ring_eq_db(sc, eq);
+		if (eq->pending >= 8)
+			ring_eq_db(sc, eq);
 
 		can_reclaim = reclaimable(eq);
 		if (can_reclaim >= 32)