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

*** 320,342 ****
                              (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)
  
  
  /*
   * Simple queue definitions.
   */
  #define SIMPLEQ_HEAD(name, type)                                        \
  struct name {                                                           \
--- 320,347 ----
                              (head)->stqh_last = &(curelm)->field.stqe_next; \
          }                                                               \
          _NOTE(CONSTCOND)                                                \
  } while (0)
  
  /*
   * 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 {                                                           \