PERFORCE change 126407 for review

[Kip Macy]

http://perforce.freebsd.org/chv.cgi?CH=126407

Change 126407 by kmacy at kmacy_home:ethng on 2007/09/14 19:17:23

	make physically contigous jumbo frames a boot time option defaulting to on

Affected files ...

.. //depot/projects/ethng/src/sys/kern/kern_mbuf.c#4 edit

Differences ...

==== //depot/projects/ethng/src/sys/kern/kern_mbuf.c#4 (text+ko) ====

@@ -99,6 +99,8 @@
 int nmbjumbop;			/* limits number of page size jumbo clusters */
 int nmbjumbo9;			/* limits number of 9k jumbo clusters */
 int nmbjumbo16;			/* limits number of 16k jumbo clusters */
+int jumbo_phys_contig = 1;      /* jumbo frames are physically contiguous */
+
 struct mbstat mbstat;
 
 static void
@@ -140,7 +142,8 @@
     "Maximum number of mbuf 16k jumbo clusters allowed");
 SYSCTL_STRUCT(_kern_ipc, OID_AUTO, mbstat, CTLFLAG_RD, &mbstat, mbstat,
     "Mbuf general information and statistics");
-
+SYSCTL_INT(_kern_ipc, OID_AUTO, jumbo_phys_contig, CTLFLAG_RW, &jumbo_phys_contig, 1,
+    "jumbo frames are physically contiguous");
 /*
  * Zones from which we allocate.
  */
@@ -227,7 +230,8 @@
 	if (nmbjumbo9 > 0)
 		uma_zone_set_max(zone_jumbo9, nmbjumbo9);
 
-	uma_zone_set_contig(zone_jumbo9);
+	if (jumbo_phys_contig)
+		uma_zone_set_contig(zone_jumbo9);
 	
 	zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES,
 	    mb_ctor_clust, mb_dtor_clust,
@@ -240,7 +244,8 @@
 	if (nmbjumbo16 > 0)
 		uma_zone_set_max(zone_jumbo16, nmbjumbo16);
 
-	uma_zone_set_contig(zone_jumbo16);
+	if (jumbo_phys_contig)
+		uma_zone_set_contig(zone_jumbo16);
 	
 	zone_ext_refcnt = uma_zcreate(MBUF_EXTREFCNT_MEM_NAME, sizeof(u_int),
 	    NULL, NULL,