svn commit: r301902 - stable/10/sys/dev/ntb/if_ntb

[Alexander Motin]

Author: mav
Date: Wed Jun 15 01:39:43 2016
New Revision: 301902
URL: https://svnweb.freebsd.org/changeset/base/301902

Log:
  MFC r300610: Re-enable write combining, disabled by default at r295486.
  
  if_ntb(4) strongly benefits from WC, improving throughput from 350Mbit/s
  to 8-10Gbit/s on my tests.

Modified:
  stable/10/sys/dev/ntb/if_ntb/if_ntb.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/dev/ntb/if_ntb/if_ntb.c
==============================================================================
--- stable/10/sys/dev/ntb/if_ntb/if_ntb.c	Tue Jun 14 23:58:02 2016	(r301901)
+++ stable/10/sys/dev/ntb/if_ntb/if_ntb.c	Wed Jun 15 01:39:43 2016	(r301902)
@@ -621,6 +621,10 @@ ntb_transport_probe(struct ntb_softc *nt
 		mw->xlat_size = 0;
 		mw->virt_addr = NULL;
 		mw->dma_addr = 0;
+
+		rc = ntb_mw_set_wc(nt->ntb, i, VM_MEMATTR_WRITE_COMBINING);
+		if (rc)
+			ntb_printf(0, "Unable to set mw%d caching\n", i);
 	}
 
 	qp_bitmap = ntb_db_valid_mask(ntb);