DLPX-25998 TCP congestion control is inadequate
Reviewed at: http://reviews.delphix.com/r/34808/

@@ -320,23 +320,28 @@
                             (head)->stqh_last = &(curelm)->field.stqe_next; \
         }                                                               \
         _NOTE(CONSTCOND)                                                \
 } while (0)
 
-#define STAILQ_FOREACH(var, head, field)                                \
-        for ((var) = ((head)->stqh_first);                              \
-                (var);                                                  \
-                (var) = ((var)->field.stqe_next))
-
 /*
  * Singly-linked Tail queue access methods.
  */
 #define STAILQ_EMPTY(head)      ((head)->stqh_first == NULL)
 #define STAILQ_FIRST(head)      ((head)->stqh_first)
 #define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next)
 
+#define STAILQ_FOREACH(var, head, field)                                \
+        for ((var) = ((head)->stqh_first);                              \
+                (var);                                                  \
+                (var) = ((var)->field.stqe_next))
 
+#define STAILQ_FOREACH_SAFE(var, head, field, tvar)                     \
+        for ((var) = STAILQ_FIRST((head));                              \
+                (var) && ((tvar) = STAILQ_NEXT((var), field), 1);       \
+                (var) = (tvar))
+
+
 /*
  * Simple queue definitions.
  */
 #define SIMPLEQ_HEAD(name, type)                                        \
 struct name {                                                           \