svn commit: r239673 - head/sys/geom/multipath

[Thomas Quinot]

Author: thomas
Date: Sat Aug 25 10:36:31 2012
New Revision: 239673
URL: http://svn.freebsd.org/changeset/base/239673

Log:
  (g_multipath_rotate): Fix algorithm so that it does rotate over all good
  providers, not just the last two.
  
  PR:		kern/170379
  Reviewed by:	mav
  MFC after:	2 weeks

Modified:
  head/sys/geom/multipath/g_multipath.c

Modified: head/sys/geom/multipath/g_multipath.c
==============================================================================
--- head/sys/geom/multipath/g_multipath.c	Sat Aug 25 09:26:37 2012	(r239672)
+++ head/sys/geom/multipath/g_multipath.c	Sat Aug 25 10:36:31 2012	(r239673)
@@ -590,19 +590,26 @@ g_multipath_destroy_geom(struct gctl_req
 static int
 g_multipath_rotate(struct g_geom *gp)
 {
-	struct g_consumer *lcp;
+	struct g_consumer *lcp, *first_good_cp = NULL;
 	struct g_multipath_softc *sc = gp->softc;
+	int active_cp_seen = 0;
 
 	g_topology_assert();
 	if (sc == NULL)
 		return (ENXIO);
 	LIST_FOREACH(lcp, &gp->consumer, consumer) {
 		if ((lcp->index & MP_BAD) == 0) {
-			if (sc->sc_active != lcp)
+			if (first_good_cp == NULL)
+				first_good_cp = lcp;
+			if (active_cp_seen)
 				break;
 		}
+		if (sc->sc_active == lcp)
+			active_cp_seen = 1;
 	}
-	if (lcp) {
+	if (lcp == NULL)
+		lcp = first_good_cp;
+	if (lcp && lcp != sc->sc_active) {
 		sc->sc_active = lcp;
 		if (sc->sc_active_active != 1)
 			printf("GEOM_MULTIPATH: %s is now active path in %s\n",