erts: Refactor rbt _yielding to use reductions

All of the Red-Black Tree _yielding functions have been
updated to work with reductions returned by the called
function instead of yielding on each element.

21 files changed, 514 insertions, 398 deletions

diff --git a/erts/emulator/beam/break.c b/erts/emulator/beam/break.c
index 273b598562..27bf2187c2 100644
--- a/erts/emulator/beam/break.c
+++ b/erts/emulator/beam/break.c
@@ -129,7 +129,7 @@ typedef struct {
     void *to_arg;
 } PrintMonitorContext;
 
-static void doit_print_link(ErtsLink *lnk, void *vpcontext)
+static int doit_print_link(ErtsLink *lnk, void *vpcontext, Sint reds)
 {
     PrintMonitorContext *pcontext = vpcontext;
     fmtfn_t to = pcontext->to;
@@ -141,10 +141,11 @@ static void doit_print_link(ErtsLink *lnk, void *vpcontext)
     } else {
 	erts_print(to, to_arg, ", %T", lnk->other.item);
     }
+    return 1;
 }
     
 
-static void doit_print_monitor(ErtsMonitor *mon, void *vpcontext)
+static int doit_print_monitor(ErtsMonitor *mon, void *vpcontext, Sint reds)
 {
     ErtsMonitorData *mdp;
     PrintMonitorContext *pcontext = vpcontext;
@@ -196,6 +197,7 @@ static void doit_print_monitor(ErtsMonitor *mon, void *vpcontext)
         /* ignore other monitors... */
         break;
     }
+    return 1;
 }
 			       
 /* Display info about an individual Erlang process */
diff --git a/erts/emulator/beam/dist.c b/erts/emulator/beam/dist.c
index 15642e1669..21f994fd3e 100644
--- a/erts/emulator/beam/dist.c
+++ b/erts/emulator/beam/dist.c
@@ -185,20 +185,22 @@ get_suspended_on_de(DistEntry *dep, erts_aint32_t unset_qflgs)
     }
 }
 
-#define ERTS_MON_LNK_FIRE_LIMIT 100
+#define ERTS_MON_LNK_FIRE_REDS 40
 
-static void monitor_connection_down(ErtsMonitor *mon, void *unused)
+static int monitor_connection_down(ErtsMonitor *mon, void *unused, Sint reds)
 {
     if (erts_monitor_is_origin(mon))
         erts_proc_sig_send_demonitor(mon);
     else
         erts_proc_sig_send_monitor_down(mon, am_noconnection);
+    return ERTS_MON_LNK_FIRE_REDS;
 }
 
-static void link_connection_down(ErtsLink *lnk, void *vdist)
+static int link_connection_down(ErtsLink *lnk, void *vdist, Sint reds)
 {
     erts_proc_sig_send_link_exit(NULL, THE_NON_VALUE, lnk,
                                  am_noconnection, NIL);
+    return ERTS_MON_LNK_FIRE_REDS;
 }
 
 typedef enum {
@@ -226,35 +228,35 @@ con_monitor_link_cleanup(void *vcmlcp)
     ErtsConMonLnkCleanup *cmlcp = vcmlcp;
     ErtsMonLnkDist *dist = cmlcp->dist;
     ErtsSchedulerData *esdp;
-    int yield;
+    int reds = CONTEXT_REDS;
 
     switch (cmlcp->state) {
     case ERTS_CML_CLEANUP_STATE_LINKS:
-        yield = erts_link_list_foreach_delete_yielding(&dist->links,
-                                                       link_connection_down,
-                                                       NULL, &cmlcp->yield_state,
-                                                       ERTS_MON_LNK_FIRE_LIMIT);
-        if (yield)
+        reds = erts_link_list_foreach_delete_yielding(&dist->links,
+                                                      link_connection_down,
+                                                      NULL, &cmlcp->yield_state,
+                                                      reds);
+        if (reds <= 0)
             break;
 
         ASSERT(!cmlcp->yield_state);
         cmlcp->state = ERTS_CML_CLEANUP_STATE_MONITORS;
     case ERTS_CML_CLEANUP_STATE_MONITORS:
-        yield = erts_monitor_list_foreach_delete_yielding(&dist->monitors,
-                                                          monitor_connection_down,
-                                                          NULL, &cmlcp->yield_state,
-                                                          ERTS_MON_LNK_FIRE_LIMIT);
-        if (yield)
+        reds = erts_monitor_list_foreach_delete_yielding(&dist->monitors,
+                                                         monitor_connection_down,
+                                                         NULL, &cmlcp->yield_state,
+                                                         reds);
+        if (reds <= 0)
             break;
 
         ASSERT(!cmlcp->yield_state);
         cmlcp->state = ERTS_CML_CLEANUP_STATE_ONAME_MONITORS;
     case ERTS_CML_CLEANUP_STATE_ONAME_MONITORS:
-        yield = erts_monitor_tree_foreach_delete_yielding(&dist->orig_name_monitors,
-                                                          monitor_connection_down,
-                                                          NULL, &cmlcp->yield_state,
-                                                          ERTS_MON_LNK_FIRE_LIMIT/2);
-        if (yield)
+        reds = erts_monitor_tree_foreach_delete_yielding(&dist->orig_name_monitors,
+                                                         monitor_connection_down,
+                                                         NULL, &cmlcp->yield_state,
+                                                         reds);
+        if (reds <= 0)
             break;
 
         cmlcp->dist = NULL;
@@ -1188,7 +1190,6 @@ erts_dsig_send_group_leader(ErtsDSigData *dsdp, Eterm leader, Eterm remote)
 #elif defined(VALGRIND)
 #include <valgrind/valgrind.h>
 #include <valgrind/memcheck.h>
-
 #  define PURIFY_MSG(msg)                                                    \
     VALGRIND_PRINTF("%s, line %d: %s", __FILE__, __LINE__, msg)
 #else
@@ -2891,7 +2892,7 @@ struct print_to_data {
     void *arg;
 };
 
-static void doit_print_monitor_info(ErtsMonitor *mon, void *vptdp)
+static int doit_print_monitor_info(ErtsMonitor *mon, void *vptdp, Sint reds)
 {
     fmtfn_t to = ((struct print_to_data *) vptdp)->to;
     void *arg = ((struct print_to_data *) vptdp)->arg;
@@ -2914,6 +2915,7 @@ static void doit_print_monitor_info(ErtsMonitor *mon, void *vptdp)
         else
 	    erts_print(to, arg, "%T\n", mdep->md.origin.other.item);
     }
+    return 1;
 }    
 
 static void print_monitor_info(fmtfn_t to, void *arg, DistEntry *dep)
@@ -2929,12 +2931,13 @@ static void print_monitor_info(fmtfn_t to, void *arg, DistEntry *dep)
     }
 }
 
-static void doit_print_link_info(ErtsLink *lnk, void *vptdp)
+static int doit_print_link_info(ErtsLink *lnk, void *vptdp, Sint reds)
 {
     struct print_to_data *ptdp = vptdp;
     ErtsLink *lnk2 = erts_link_to_other(lnk, NULL);
     erts_print(ptdp->to, ptdp->arg, "Remote link: %T %T\n",
 	       lnk2->other.item, lnk->other.item);
+    return 1;
 }
 
 static void print_link_info(fmtfn_t to, void *arg, DistEntry *dep)
@@ -4150,8 +4153,8 @@ typedef struct {
     Uint i;
 } ErtsNodesMonitorContext;
 
-static void
-save_nodes_monitor(ErtsMonitor *mon, void *vctxt)
+static int
+save_nodes_monitor(ErtsMonitor *mon, void *vctxt, Sint reds)
 {
     ErtsNodesMonitorContext *ctxt = vctxt;
     ErtsMonitorData *mdp = erts_monitor_to_data(mon);
@@ -4163,6 +4166,7 @@ save_nodes_monitor(ErtsMonitor *mon, void *vctxt)
     ctxt->nmdp[ctxt->i].options = mdp->origin.other.item;
 
     ctxt->i++;
+    return 1;
 }
 
 static void
@@ -4295,8 +4299,8 @@ typedef struct {
 } ErtsNodesMonitorInfoContext;
 
 
-static void
-nodes_monitor_info(ErtsMonitor *mon, void *vctxt)
+static int
+nodes_monitor_info(ErtsMonitor *mon, void *vctxt, Sint reds)
 {
     ErtsMonitorDataExtended *mdep;
     ErtsNodesMonitorInfoContext *ctxt = vctxt;
@@ -4343,6 +4347,7 @@ nodes_monitor_info(ErtsMonitor *mon, void *vctxt)
     ctxt->hpp = hpp;
     ctxt->szp = szp;
     ctxt->res = res;
+    return 1;
 }
 
 Eterm
diff --git a/erts/emulator/beam/dist.h b/erts/emulator/beam/dist.h
index 845fab229a..a8ccd1eaec 100644
--- a/erts/emulator/beam/dist.h
+++ b/erts/emulator/beam/dist.h
@@ -404,5 +404,4 @@ extern Uint erts_dist_cache_size(void);
 
 extern Sint erts_abort_connection_rwunlock(DistEntry *dep);
 
-
 #endif
diff --git a/erts/emulator/beam/erl_alloc_util.c b/erts/emulator/beam/erl_alloc_util.c
index d238d38d27..8d4464969a 100644
--- a/erts/emulator/beam/erl_alloc_util.c
+++ b/erts/emulator/beam/erl_alloc_util.c
@@ -7503,7 +7503,7 @@ static int gather_ahist_scan(Allctr_t *allocator,
     return blocks_scanned;
 }
 
-static void gather_ahist_append_result(hist_tree_t *node, void *arg)
+static int gather_ahist_append_result(hist_tree_t *node, void *arg, Sint reds)
 {
     gather_ahist_t *state = (gather_ahist_t*)arg;
 
@@ -7537,6 +7537,7 @@ static void gather_ahist_append_result(hist_tree_t *node, void *arg)
 
     /* Plain free is intentional. */
     free(node);
+    return 1;
 }
 
 static void gather_ahist_send(gather_ahist_t *state)
@@ -7595,11 +7596,11 @@ static int gather_ahist_finish(void *arg)
         state->building_result = 1;
     }
 
-    if (hist_tree_rbt_foreach_destroy_yielding(&state->hist_tree,
-                                               &gather_ahist_append_result,
-                                               state,
-                                               &state->hist_tree_yield,
-                                               BLOCKSCAN_REDUCTIONS)) {
+    if (!hist_tree_rbt_foreach_destroy_yielding(&state->hist_tree,
+                                                &gather_ahist_append_result,
+                                                state,
+                                                &state->hist_tree_yield,
+                                                BLOCKSCAN_REDUCTIONS)) {
         return 1;
     }
 
@@ -7608,10 +7609,11 @@ static int gather_ahist_finish(void *arg)
     return 0;
 }
 
-static void gather_ahist_destroy_result(hist_tree_t *node, void *arg)
+static int gather_ahist_destroy_result(hist_tree_t *node, void *arg, Sint reds)
 {
     (void)arg;
     free(node);
+    return 1;
 }
 
 static void gather_ahist_abort(void *arg)
diff --git a/erts/emulator/beam/erl_bif_info.c b/erts/emulator/beam/erl_bif_info.c
index 6f4e34e1a8..74708b2caa 100644
--- a/erts/emulator/beam/erl_bif_info.c
+++ b/erts/emulator/beam/erl_bif_info.c
@@ -227,7 +227,7 @@ bld_magic_ref_bin_list(Uint **hpp, Uint *szp, ErlOffHeap* oh)
           }).
 */
 
-static void do_calc_mon_size(ErtsMonitor *mon, void *vpsz)
+static int do_calc_mon_size(ErtsMonitor *mon, void *vpsz, Sint reds)
 {
     ErtsMonitorData *mdp = erts_monitor_to_data(mon);
     Uint *psz = vpsz;
@@ -238,7 +238,8 @@ static void do_calc_mon_size(ErtsMonitor *mon, void *vpsz)
     else
         *psz += is_immed(mon->other.item) ? 0 : NC_HEAP_SIZE(mon->other.item);
 
-    *psz += 9; /* CONS + 6-tuple */ 
+    *psz += 9; /* CONS + 6-tuple */
+    return 1;
 }
 
 typedef struct {
@@ -248,7 +249,7 @@ typedef struct {
     Eterm tag;
 } MonListContext;
 
-static void do_make_one_mon_element(ErtsMonitor *mon, void * vpmlc)
+static int do_make_one_mon_element(ErtsMonitor *mon, void * vpmlc, Sint reds)
 {
     ErtsMonitorData *mdp = erts_monitor_to_data(mon);
     MonListContext *pmlc = vpmlc;
@@ -319,6 +320,7 @@ static void do_make_one_mon_element(ErtsMonitor *mon, void * vpmlc)
     pmlc->hp += 7;
     pmlc->res = CONS(pmlc->hp, tup, pmlc->res);
     pmlc->hp += 2;
+    return 1;
 }
 
 static Eterm 
@@ -328,7 +330,7 @@ make_monitor_list(Process *p, int tree, ErtsMonitor *root, Eterm tail)
     Uint sz = 0;
     MonListContext mlc;
     void (*foreach)(ErtsMonitor *,
-                    void (*)(ErtsMonitor *, void *),
+                    ErtsMonitorFunc,
                     void *);
 
     foreach = tree ? erts_monitor_tree_foreach : erts_monitor_list_foreach;
@@ -354,7 +356,7 @@ make_monitor_list(Process *p, int tree, ErtsMonitor *root, Eterm tail)
           }).
 */
 
-static void calc_lnk_size(ErtsLink *lnk, void *vpsz)
+static int calc_lnk_size(ErtsLink *lnk, void *vpsz, Sint reds)
 {
     Uint *psz = vpsz;
     Uint sz = 0;
@@ -364,7 +366,8 @@ static void calc_lnk_size(ErtsLink *lnk, void *vpsz)
 
     *psz += sz;
     *psz += is_immed(lnk->other.item) ? 0 : size_object(lnk->other.item);
-    *psz += 7; /* CONS + 4-tuple */ 
+    *psz += 7; /* CONS + 4-tuple */
+    return 1;
 }
 
 typedef struct {
@@ -374,7 +377,7 @@ typedef struct {
     Eterm tag;
 } LnkListContext;
 
-static void make_one_lnk_element(ErtsLink *lnk, void * vpllc)
+static int make_one_lnk_element(ErtsLink *lnk, void * vpllc, Sint reds)
 {
     LnkListContext *pllc = vpllc;
     Eterm tup, t, pid, id;
@@ -411,6 +414,7 @@ static void make_one_lnk_element(ErtsLink *lnk, void * vpllc)
     pllc->hp += 5;
     pllc->res = CONS(pllc->hp, tup, pllc->res);
     pllc->hp += 2;
+    return 1;
 }
 
 static Eterm 
@@ -420,7 +424,7 @@ make_link_list(Process *p, int tree, ErtsLink *root, Eterm tail)
     Uint sz = 0;
     LnkListContext llc;
     void (*foreach)(ErtsLink *,
-                    void (*)(ErtsLink *, void *),
+                    ErtsLinkFunc,
                     void *);
 
     foreach = tree ? erts_link_tree_foreach : erts_link_list_foreach;
@@ -519,16 +523,17 @@ do {							\
     }							\
  } while (0)
 
-static void collect_one_link(ErtsLink *lnk, void *vmicp)
+static int collect_one_link(ErtsLink *lnk, void *vmicp, Sint reds)
 {
     MonitorInfoCollection *micp = vmicp;
     EXTEND_MONITOR_INFOS(micp);
     micp->mi[micp->mi_i].entity.term = lnk->other.item;
     micp->sz += 2 + NC_HEAP_SIZE(lnk->other.item);
     micp->mi_i++;
+    return 1;
 } 
 
-static void collect_one_origin_monitor(ErtsMonitor *mon, void *vmicp)
+static int collect_one_origin_monitor(ErtsMonitor *mon, void *vmicp, Sint reds)
 {
     if (erts_monitor_is_origin(mon)) {
         MonitorInfoCollection *micp = vmicp;
@@ -573,9 +578,10 @@ static void collect_one_origin_monitor(ErtsMonitor *mon, void *vmicp)
             break;
         }
     }
+    return 1;
 }
 
-static void collect_one_target_monitor(ErtsMonitor *mon, void *vmicp)
+static int collect_one_target_monitor(ErtsMonitor *mon, void *vmicp, Sint reds)
 {
     MonitorInfoCollection *micp = vmicp;
  
@@ -612,8 +618,8 @@ static void collect_one_target_monitor(ErtsMonitor *mon, void *vmicp)
         default:
             break;
         }
-
     }
+    return 1;
 }
 
 typedef struct {
@@ -653,8 +659,8 @@ do {									\
     }									\
  } while (0)
 
-static void
-collect_one_suspend_monitor(ErtsMonitor *mon, void *vsmicp)
+static int
+collect_one_suspend_monitor(ErtsMonitor *mon, void *vsmicp, Sint reds)
 {
     if (mon->type == ERTS_MON_TYPE_SUSPEND) {
         Sint count;
@@ -678,6 +684,7 @@ collect_one_suspend_monitor(ErtsMonitor *mon, void *vsmicp)
 
 	smicp->smi_i++;
     }
+    return 1;
 }
 
 /*
@@ -3144,14 +3151,16 @@ BIF_RETTYPE system_info_1(BIF_ALIST_1)
     BIF_ERROR(BIF_P, BADARG);
 }
 
-static void monitor_size(ErtsMonitor *mon, void *vsz)
+static int monitor_size(ErtsMonitor *mon, void *vsz, Sint reds)
 {
     *((Uint *) vsz) = erts_monitor_size(mon);
+    return 1;
 }
 
-static void link_size(ErtsMonitor *lnk, void *vsz)
+static int link_size(ErtsMonitor *lnk, void *vsz, Sint reds)
 {
     *((Uint *) vsz) = erts_link_size(lnk);
+    return 1;
 }
 
 /**********************************************************************/ 
diff --git a/erts/emulator/beam/erl_db.c b/erts/emulator/beam/erl_db.c
index df6f42edd3..0d570517ec 100644
--- a/erts/emulator/beam/erl_db.c
+++ b/erts/emulator/beam/erl_db.c
@@ -3912,7 +3912,7 @@ struct free_fixations_ctx
     SWord cnt;
 };
 
-static void free_fixations_op(DbFixation* fix, void* vctx)
+static int free_fixations_op(DbFixation* fix, void* vctx, Sint reds)
 {
     struct free_fixations_ctx* ctx = (struct free_fixations_ctx*) vctx;
     erts_aint_t diff;
@@ -3949,6 +3949,7 @@ static void free_fixations_op(DbFixation* fix, void* vctx)
         ERTS_ETS_MISC_MEM_ADD(-sizeof(DbFixation));
     }
     ctx->cnt++;
+    return 1;
 }
 
 int erts_db_execute_free_fixation(Process* p, DbFixation* fix)
@@ -4093,7 +4094,7 @@ struct fixing_procs_info_ctx
     Eterm list;
 };
 
-static void fixing_procs_info_op(DbFixation* fix, void* vctx)
+static int fixing_procs_info_op(DbFixation* fix, void* vctx, Sint reds)
 {
     struct fixing_procs_info_ctx* ctx = (struct fixing_procs_info_ctx*) vctx;
     Eterm* hp;
@@ -4103,6 +4104,7 @@ static void fixing_procs_info_op(DbFixation* fix, void* vctx)
     tpl = TUPLE2(hp, fix->procs.p->common.id, make_small(fix->counter));
     hp += 3;
     ctx->list = CONS(hp, tpl, ctx->list);
+    return 1;
 }
 
 static Eterm table_info(Process* p, DbTable* tb, Eterm What)
diff --git a/erts/emulator/beam/erl_hl_timer.c b/erts/emulator/beam/erl_hl_timer.c
index 75ad6de2c9..b0eb0e85c0 100644
--- a/erts/emulator/beam/erl_hl_timer.c
+++ b/erts/emulator/beam/erl_hl_timer.c
@@ -2263,9 +2263,10 @@ parse_bif_timer_options(Eterm option_list, int *async,
     return 1;
 }
 
-static void
-exit_cancel_bif_timer(ErtsBifTimer *tmr, void *vesdp)
+static int
+exit_cancel_bif_timer(ErtsBifTimer *tmr, void *vesdp, Sint reds)
 {
+#define ERTS_BTM_CANCEL_REDS 80
     ErtsSchedulerData *esdp = (ErtsSchedulerData *) vesdp;
     Uint32 sid, roflgs;
     erts_aint_t state;
@@ -2290,7 +2291,7 @@ exit_cancel_bif_timer(ErtsBifTimer *tmr, void *vesdp)
 
         if (sid != (Uint32) esdp->no) {
             queue_canceled_timer(esdp, sid, (ErtsTimer *) tmr);
-            return;
+            return ERTS_BTM_CANCEL_REDS;
         }
 
         if (tmr->btm.tree.parent != ERTS_HLT_PFIELD_NOT_IN_TABLE) {
@@ -2306,14 +2307,9 @@ exit_cancel_bif_timer(ErtsBifTimer *tmr, void *vesdp)
         hl_timer_dec_refc(&tmr->type.hlt, roflgs);
     else
         tw_timer_dec_refc(&tmr->type.twt);
+    return ERTS_BTM_CANCEL_REDS;
 }
 
-#ifdef ERTS_HLT_DEBUG
-#  define ERTS_BTM_MAX_DESTROY_LIMIT 2
-#else
-#  define ERTS_BTM_MAX_DESTROY_LIMIT 50
-#endif
-
 typedef struct {
     ErtsBifTimers *bif_timers;
     union {
@@ -2321,10 +2317,9 @@ typedef struct {
     } u;
 } ErtsBifTimerYieldState;
 
-int erts_cancel_bif_timers(Process *p, ErtsBifTimers **btm, void **vyspp)
+int erts_cancel_bif_timers(Process *p, ErtsBifTimers **btm, void **vyspp, int reds)
 {
     ErtsSchedulerData *esdp = erts_proc_sched_data(p);
-
     ErtsBifTimerYieldState ys = {*btm, {ERTS_RBT_YIELD_STAT_INITER}};
     ErtsBifTimerYieldState *ysp;
     int res;
@@ -2337,9 +2332,9 @@ int erts_cancel_bif_timers(Process *p, ErtsBifTimers **btm, void **vyspp)
 						exit_cancel_bif_timer,
 						(void *) esdp,
 						&ysp->u.proc_btm_yield_state,
-						ERTS_BTM_MAX_DESTROY_LIMIT);
+						reds);
 
-    if (res == 0) {
+    if (res > 0) {
 	if (ysp != &ys)
 	    erts_free(ERTS_ALC_T_BTM_YIELD_STATE, ysp);
 	*vyspp = NULL;
@@ -2819,8 +2814,8 @@ btm_print(ErtsBifTimer *tmr, void *vbtmp, ErtsMonotonicTime tpos, int is_hlt)
 	       (Sint64) left);
 }
 
-static void
-btm_tree_print(ErtsBifTimer *tmr, void *vbtmp)
+static int
+btm_tree_print(ErtsBifTimer *tmr, void *vbtmp, Sint reds)
 {
     int is_hlt = !!(tmr->type.head.roflgs & ERTS_TMR_ROFLG_HLT);
     ErtsMonotonicTime tpos;
@@ -2829,6 +2824,7 @@ btm_tree_print(ErtsBifTimer *tmr, void *vbtmp)
     else
         tpos = erts_tweel_read_timeout(&tmr->type.twt.u.tw_tmr);
     btm_print(tmr, vbtmp, tpos, is_hlt);
+    return 1;
 }
 
 void
@@ -2860,8 +2856,8 @@ typedef struct {
     void *arg;
 } ErtsBTMForeachDebug;
 
-static void
-debug_btm_foreach(ErtsBifTimer *tmr, void *vbtmfd)
+static int
+debug_btm_foreach(ErtsBifTimer *tmr, void *vbtmfd, Sint reds)
 {
     if (erts_atomic32_read_nob(&tmr->btm.state) == ERTS_TMR_STATE_ACTIVE) {
 	ErtsBTMForeachDebug *btmfd = (ErtsBTMForeachDebug *) vbtmfd;
@@ -2870,6 +2866,7 @@ debug_btm_foreach(ErtsBifTimer *tmr, void *vbtmfd)
                     : tmr->type.head.receiver.proc->common.id);
 	(*btmfd->func)(id, tmr->btm.message, tmr->btm.bp, btmfd->arg);
     }
+    return 1;
 }
 
 void
@@ -2918,8 +2915,8 @@ debug_callback_timer_foreach_list(ErtsHLTimer *tmr, void *vdfct)
 		      tmr->head.u.arg);
 }
 
-static void
-debug_callback_timer_foreach(ErtsHLTimer *tmr, void *vdfct)
+static int
+debug_callback_timer_foreach(ErtsHLTimer *tmr, void *vdfct, Sint reds)
 {
     ErtsDebugForeachCallbackTimer *dfct
 	= (ErtsDebugForeachCallbackTimer *) vdfct;
@@ -2934,6 +2931,7 @@ debug_callback_timer_foreach(ErtsHLTimer *tmr, void *vdfct)
 	(*dfct->func)(dfct->arg,
 		      tmr->timeout,
 		      tmr->head.u.arg);
+    return 1;
 }
 
 static void
@@ -2981,7 +2979,8 @@ erts_debug_callback_timer_foreach(void (*tclbk)(void *),
 
 	if (srv->yield.root)
 	    debug_callback_timer_foreach(srv->yield.root,
-					 (void *) &dfct);
+					 (void *) &dfct,
+                                         -1);
 
 	time_rbt_foreach(srv->time_tree,
 			 debug_callback_timer_foreach,
diff --git a/erts/emulator/beam/erl_hl_timer.h b/erts/emulator/beam/erl_hl_timer.h
index e6f5e8b67d..29c873868b 100644
--- a/erts/emulator/beam/erl_hl_timer.h
+++ b/erts/emulator/beam/erl_hl_timer.h
@@ -56,7 +56,7 @@ void erts_cancel_proc_timer(Process *);
 void erts_set_port_timer(Port *, Sint64);
 void erts_cancel_port_timer(Port *);
 Sint64 erts_read_port_timer(Port *);
-int erts_cancel_bif_timers(Process *, ErtsBifTimers **, void **);
+int erts_cancel_bif_timers(Process *, ErtsBifTimers **, void **, int);
 int erts_detach_accessor_bif_timers(Process *, ErtsBifTimers *, void **);
 ErtsHLTimerService *erts_create_timer_service(void);
 void erts_hl_timer_init(void);
diff --git a/erts/emulator/beam/erl_monitor_link.c b/erts/emulator/beam/erl_monitor_link.c
index 48d9bd4ca5..3dabd79190 100644
--- a/erts/emulator/beam/erl_monitor_link.c
+++ b/erts/emulator/beam/erl_monitor_link.c
@@ -335,7 +335,7 @@ ml_rbt_delete(ErtsMonLnkNode **root, ErtsMonLnkNode *ml)
 
 static void
 ml_rbt_foreach(ErtsMonLnkNode *root,
-               void (*func)(ErtsMonLnkNode *, void *),
+               ErtsMonLnkNodeFunc func,
                void *arg)
 {
     mon_lnk_rbt_foreach(root, func, arg);
@@ -348,7 +348,7 @@ typedef struct {
 
 static int
 ml_rbt_foreach_yielding(ErtsMonLnkNode *root,
-                        void (*func)(ErtsMonLnkNode *, void *),
+                        ErtsMonLnkNodeFunc func,
                         void *arg,
                         void **vyspp,
                         Sint limit)
@@ -362,7 +362,7 @@ ml_rbt_foreach_yielding(ErtsMonLnkNode *root,
 	ysp = &ys;
     res = mon_lnk_rbt_foreach_yielding(ysp->root, func, arg,
                                        &ysp->rbt_ystate, limit);
-    if (res == 0) {
+    if (res > 0) {
 	if (ysp != &ys)
 	    erts_free(ERTS_ALC_T_ML_YIELD_STATE, ysp);
 	*vyspp = NULL;
@@ -383,22 +383,22 @@ ml_rbt_foreach_yielding(ErtsMonLnkNode *root,
 }
 
 typedef struct {
-    void (*func)(ErtsMonLnkNode *, void *);
+    ErtsMonLnkNodeFunc func;
     void *arg;
 } ErtsMonLnkForeachDeleteContext;
 
-static void
-rbt_wrap_foreach_delete(ErtsMonLnkNode *ml, void *vctxt)
+static int
+rbt_wrap_foreach_delete(ErtsMonLnkNode *ml, void *vctxt, Sint reds)
 {
     ErtsMonLnkForeachDeleteContext *ctxt = vctxt;
     ERTS_ML_ASSERT(ml->flags & ERTS_ML_FLG_IN_TABLE);
     ml->flags &= ~ERTS_ML_FLG_IN_TABLE;
-    ctxt->func(ml, ctxt->arg);
+    return ctxt->func(ml, ctxt->arg, reds);
 }
 
 static void
 ml_rbt_foreach_delete(ErtsMonLnkNode **root,
-                      void (*func)(ErtsMonLnkNode *, void *),
+                      ErtsMonLnkNodeFunc func,
                       void *arg)
 {
     ErtsMonLnkForeachDeleteContext ctxt;
@@ -411,7 +411,7 @@ ml_rbt_foreach_delete(ErtsMonLnkNode **root,
 
 static int
 ml_rbt_foreach_delete_yielding(ErtsMonLnkNode **root,
-                               void (*func)(ErtsMonLnkNode *, void *),
+                               ErtsMonLnkNodeFunc func,
                                void *arg,
                                void **vyspp,
                                Sint limit)
@@ -433,7 +433,7 @@ ml_rbt_foreach_delete_yielding(ErtsMonLnkNode **root,
                                                (void *) &ctxt,
                                                &ysp->rbt_ystate,
                                                limit);
-    if (res == 0) {
+    if (res > 0) {
 	if (ysp != &ys)
 	    erts_free(ERTS_ALC_T_ML_YIELD_STATE, ysp);
 	*vyspp = NULL;
@@ -459,12 +459,11 @@ ml_rbt_foreach_delete_yielding(ErtsMonLnkNode **root,
 
 static int
 ml_dl_list_foreach_yielding(ErtsMonLnkNode *list,
-                            void (*func)(ErtsMonLnkNode *, void *),
+                            ErtsMonLnkNodeFunc func,
                             void *arg,
                             void **vyspp,
-                            Sint limit)
+                            Sint reds)
 {
-    Sint cnt = 0;
     ErtsMonLnkNode *ml = (ErtsMonLnkNode *) *vyspp;
 
     ERTS_ML_ASSERT(!ml || list);
@@ -475,28 +474,26 @@ ml_dl_list_foreach_yielding(ErtsMonLnkNode *list,
     if (ml) {
         do {
             ERTS_ML_ASSERT(ml->flags & ERTS_ML_FLG_IN_TABLE);
-            func(ml, arg);
+            reds -= func(ml, arg, reds);
             ml = ml->node.list.next;
-            cnt++;
-        } while (ml != list && cnt < limit);
+        } while (ml != list && reds > 0);
         if (ml != list) {
             *vyspp = (void *) ml;
-            return 1; /* yield */
+            return 0; /* yield */
         }
     }
 
     *vyspp = NULL;
-    return 0; /* done */
+    return reds <= 0 ? 1 : reds; /* done */
 }
 
 static int
 ml_dl_list_foreach_delete_yielding(ErtsMonLnkNode **list,
-                                   void (*func)(ErtsMonLnkNode *, void *),
+                                   ErtsMonLnkNodeFunc func,
                                    void *arg,
                                    void **vyspp,
-                                   Sint limit)
+                                   Sint reds)
 {
-    Sint cnt = 0;
     ErtsMonLnkNode *first = *list;
     ErtsMonLnkNode *ml = (ErtsMonLnkNode *) *vyspp;
 
@@ -510,19 +507,18 @@ ml_dl_list_foreach_delete_yielding(ErtsMonLnkNode **list,
             ErtsMonLnkNode *next = ml->node.list.next;
             ERTS_ML_ASSERT(ml->flags & ERTS_ML_FLG_IN_TABLE);
             ml->flags &= ~ERTS_ML_FLG_IN_TABLE;
-            func(ml, arg);
+            reds -= func(ml, arg, reds);
             ml = next;
-            cnt++;
-        } while (ml != first && cnt < limit);
+        } while (ml != first && reds > 0);
         if (ml != first) {
             *vyspp = (void *) ml;
-            return 1; /* yield */
+            return 0; /* yield */
         }
     }
 
     *vyspp = NULL;
     *list = NULL;
-    return 0; /* done */
+    return reds <= 0 ? 1 : reds; /* done */
 }
 
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
@@ -666,91 +662,91 @@ erts_monitor_tree_delete(ErtsMonitor **root, ErtsMonitor *mon)
 
 void
 erts_monitor_tree_foreach(ErtsMonitor *root,
-                          void (*func)(ErtsMonitor *, void *),
+                          ErtsMonitorFunc func,
                           void *arg)
 {
     ml_rbt_foreach((ErtsMonLnkNode *) root,
-                   (void (*)(ErtsMonLnkNode*, void*)) func,
+                   (ErtsMonLnkNodeFunc) func,
                    arg);
 }
 
 int
 erts_monitor_tree_foreach_yielding(ErtsMonitor *root,
-                                   void (*func)(ErtsMonitor *, void *),
+                                   ErtsMonitorFunc func,
                                    void *arg,
                                    void **vyspp,
                                    Sint limit)
 {
     return ml_rbt_foreach_yielding((ErtsMonLnkNode *) root,
-                                   (void (*)(ErtsMonLnkNode*, void*)) func,
+                                   (int (*)(ErtsMonLnkNode*, void*, Sint)) func,
                                    arg, vyspp, limit);
 }
 
 void
 erts_monitor_tree_foreach_delete(ErtsMonitor **root,
-                                 void (*func)(ErtsMonitor *, void *),
+                                 ErtsMonitorFunc func,
                                  void *arg)
 {
     ml_rbt_foreach_delete((ErtsMonLnkNode **) root,
-                          (void (*)(ErtsMonLnkNode*, void*)) func,
+                          (int (*)(ErtsMonLnkNode*, void*, Sint)) func,
                           arg);
 }
 
 int
 erts_monitor_tree_foreach_delete_yielding(ErtsMonitor **root,
-                                          void (*func)(ErtsMonitor *, void *),
+                                          ErtsMonitorFunc func,
                                           void *arg,
                                           void **vyspp,
                                           Sint limit)
 {
     return ml_rbt_foreach_delete_yielding((ErtsMonLnkNode **) root,
-                                          (void (*)(ErtsMonLnkNode*, void*)) func,
+                                          (int (*)(ErtsMonLnkNode*, void*, Sint)) func,
                                           arg, vyspp, limit);
 }
 
 void
 erts_monitor_list_foreach(ErtsMonitor *list,
-                          void (*func)(ErtsMonitor *, void *),
+                          ErtsMonitorFunc func,
                           void *arg)
 {
     void *ystate = NULL;
-    while (ml_dl_list_foreach_yielding((ErtsMonLnkNode *) list,
-                                       (void (*)(ErtsMonLnkNode *, void *)) func,
-                                       arg, &ystate, (Sint) INT_MAX));
+    while (!ml_dl_list_foreach_yielding((ErtsMonLnkNode *) list,
+                                        (int (*)(ErtsMonLnkNode *, void *, Sint)) func,
+                                        arg, &ystate, (Sint) INT_MAX));
 }
 
 int
 erts_monitor_list_foreach_yielding(ErtsMonitor *list,
-                                   void (*func)(ErtsMonitor *, void *),
+                                   ErtsMonitorFunc func,
                                    void *arg,
                                    void **vyspp,
                                    Sint limit)
 {
     return ml_dl_list_foreach_yielding((ErtsMonLnkNode *) list,
-                                       (void (*)(ErtsMonLnkNode *, void *)) func,
+                                       (int (*)(ErtsMonLnkNode *, void *, Sint)) func,
                                        arg, vyspp, limit);
 }
 
 void
 erts_monitor_list_foreach_delete(ErtsMonitor **list,
-                                 void (*func)(ErtsMonitor *, void *),
+                                 ErtsMonitorFunc func,
                                  void *arg)
 {
     void *ystate = NULL;
-    while (ml_dl_list_foreach_delete_yielding((ErtsMonLnkNode **) list,
-                                              (void (*)(ErtsMonLnkNode*, void*)) func,
-                                              arg, &ystate, (Sint) INT_MAX));
+    while (!ml_dl_list_foreach_delete_yielding((ErtsMonLnkNode **) list,
+                                               (int (*)(ErtsMonLnkNode*, void*, Sint)) func,
+                                               arg, &ystate, (Sint) INT_MAX));
 }
 
 int
 erts_monitor_list_foreach_delete_yielding(ErtsMonitor **list,
-                                          void (*func)(ErtsMonitor *, void *),
+                                          ErtsMonitorFunc func,
                                           void *arg,
                                           void **vyspp,
                                           Sint limit)
 {
     return ml_dl_list_foreach_delete_yielding((ErtsMonLnkNode **) list,
-                                              (void (*)(ErtsMonLnkNode*, void*)) func,
+                                              (int (*)(ErtsMonLnkNode*, void*, Sint)) func,
                                               arg, vyspp, limit);
 }
 
@@ -1074,92 +1070,92 @@ erts_link_tree_delete(ErtsLink **root, ErtsLink *lnk)
 
 void
 erts_link_tree_foreach(ErtsLink *root,
-                       void (*func)(ErtsLink *, void *),
+                       ErtsLinkFunc func,
                        void *arg)
 {
     ml_rbt_foreach((ErtsMonLnkNode *) root,
-                   (void (*)(ErtsMonLnkNode*, void*)) func,
+                   (ErtsMonLnkNodeFunc) func,
                    arg);
 
 }
 
 int
 erts_link_tree_foreach_yielding(ErtsLink *root,
-                                void (*func)(ErtsLink *, void *),
+                                ErtsLinkFunc func,
                                 void *arg,
                                 void **vyspp,
                                 Sint limit)
 {
     return ml_rbt_foreach_yielding((ErtsMonLnkNode *) root,
-                                   (void (*)(ErtsMonLnkNode*, void*)) func,
+                                   (ErtsMonLnkNodeFunc) func,
                                    arg, vyspp, limit);
 }
 
 void
 erts_link_tree_foreach_delete(ErtsLink **root,
-                              void (*func)(ErtsLink *, void *),
+                              ErtsLinkFunc func,
                               void *arg)
 {
     ml_rbt_foreach_delete((ErtsMonLnkNode **) root,
-                          (void (*)(ErtsMonLnkNode*, void*)) func,
+                          (ErtsMonLnkNodeFunc) func,
                           arg);
 }
 
 int
 erts_link_tree_foreach_delete_yielding(ErtsLink **root,
-                                       void (*func)(ErtsLink *, void *),
+                                       ErtsLinkFunc func,
                                        void *arg,
                                        void **vyspp,
                                        Sint limit)
 {
     return ml_rbt_foreach_delete_yielding((ErtsMonLnkNode **) root,
-                                          (void (*)(ErtsMonLnkNode*, void*)) func,
+                                          (ErtsMonLnkNodeFunc) func,
                                           arg, vyspp, limit);
 }
 
 void
 erts_link_list_foreach(ErtsLink *list,
-                       void (*func)(ErtsLink *, void *),
+                       ErtsLinkFunc func,
                        void *arg)
 {
     void *ystate = NULL;
-    while (ml_dl_list_foreach_yielding((ErtsMonLnkNode *) list,
-                                       (void (*)(ErtsMonLnkNode *, void *)) func,
-                                       arg, &ystate, (Sint) INT_MAX));
+    while (!ml_dl_list_foreach_yielding((ErtsMonLnkNode *) list,
+                                        (ErtsMonLnkNodeFunc) func,
+                                        arg, &ystate, (Sint) INT_MAX));
 }
 
 int
 erts_link_list_foreach_yielding(ErtsLink *list,
-                                void (*func)(ErtsLink *, void *),
+                                ErtsLinkFunc func,
                                 void *arg,
                                 void **vyspp,
                                 Sint limit)
 {
     return ml_dl_list_foreach_yielding((ErtsMonLnkNode *) list,
-                                       (void (*)(ErtsMonLnkNode *, void *)) func,
+                                       (ErtsMonLnkNodeFunc) func,
                                        arg, vyspp, limit);
 }
 
 void
 erts_link_list_foreach_delete(ErtsLink **list,
-                               void (*func)(ErtsLink *, void *),
+                               ErtsLinkFunc func,
                                void *arg)
 {
     void *ystate = NULL;
-    while (ml_dl_list_foreach_delete_yielding((ErtsMonLnkNode **) list,
-                                              (void (*)(ErtsMonLnkNode*, void*)) func,
-                                              arg, &ystate, (Sint) INT_MAX));
+    while (!ml_dl_list_foreach_delete_yielding((ErtsMonLnkNode **) list,
+                                               (ErtsMonLnkNodeFunc) func,
+                                               arg, &ystate, (Sint) INT_MAX));
 }
 
 int
 erts_link_list_foreach_delete_yielding(ErtsLink **list,
-                                       void (*func)(ErtsLink *, void *),
+                                       int (*func)(ErtsLink *, void *, Sint),
                                        void *arg,
                                        void **vyspp,
                                        Sint limit)
 {
     return ml_dl_list_foreach_delete_yielding((ErtsMonLnkNode **) list,
-                                              (void (*)(ErtsMonLnkNode*, void*)) func,
+                                              (ErtsMonLnkNodeFunc) func,
                                               arg, vyspp, limit);
 }
 
diff --git a/erts/emulator/beam/erl_monitor_link.h b/erts/emulator/beam/erl_monitor_link.h
index ed7bf7d54a..eff861fce8 100644
--- a/erts/emulator/beam/erl_monitor_link.h
+++ b/erts/emulator/beam/erl_monitor_link.h
@@ -439,6 +439,7 @@
     (ERTS_ML_FLG_EXTENDED|ERTS_ML_FLG_NAME)
 
 typedef struct ErtsMonLnkNode__ ErtsMonLnkNode;
+typedef int (*ErtsMonLnkNodeFunc)(ErtsMonLnkNode *, void *, Sint);
 
 typedef struct {
     UWord parent; /* Parent ptr and flags... */
@@ -622,6 +623,7 @@ erts_ml_dl_list_last__(ErtsMonLnkNode *list)
 
 
 typedef struct ErtsMonLnkNode__ ErtsMonitor;
+typedef int (*ErtsMonitorFunc)(ErtsMonitor *, void *, Sint);
 
 typedef struct {
     ErtsMonitor origin;
@@ -653,6 +655,7 @@ struct ErtsMonitorDataExtended__ {
 
 typedef struct ErtsMonitorSuspend__ ErtsMonitorSuspend;
 
+
 struct ErtsMonitorSuspend__ {
     ErtsMonitorData md; /* origin = suspender; target = suspendee */
     ErtsMonitorSuspend *next;
@@ -685,7 +688,7 @@ ErtsMonitor *erts_monitor_tree_lookup(ErtsMonitor *root, Eterm key);
  *
  * @brief Lookup or insert a monitor in a monitor tree
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'mon' monitor is not part of any tree or list
  * If the above is not true, bad things will happen.
  *
@@ -711,7 +714,7 @@ ErtsMonitor *erts_monotor_tree_lookup_insert(ErtsMonitor **root,
  * If it is not found, creates a monitor and returns a pointer to the
  * origin monitor.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - no target monitors with the key 'target' exists in the tree.
  * If the above is not true, bad things will happen.
  *
@@ -738,7 +741,7 @@ ErtsMonitor *erts_monitor_tree_lookup_create(ErtsMonitor **root, int *created,
  *
  * @brief Insert a monitor in a monitor tree
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - no monitors with the same key that 'mon' exist in the tree
  * - 'mon' is not part of any list of tree
  * If the above are not true, bad things will happen.
@@ -754,7 +757,7 @@ void erts_monitor_tree_insert(ErtsMonitor **root, ErtsMonitor *mon);
  *
  * @brief Replace a monitor in a monitor tree
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'old' monitor and 'new' monitor have exactly the same key
  * - 'old' monitor is part of the tree
  * - 'new' monitor is not part of any tree or list
@@ -774,7 +777,7 @@ void erts_monitor_tree_replace(ErtsMonitor **root, ErtsMonitor *old,
  *
  * @brief Delete a monitor from a monitor tree
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'mon' monitor is part of the tree
  * If the above is not true, bad things will happen.
  *
@@ -789,7 +792,7 @@ void erts_monitor_tree_delete(ErtsMonitor **root, ErtsMonitor *mon);
  *
  * @brief Call a function for each monitor in a monitor tree
  *
- * The funcion 'func' will be called with a pointer to a monitor
+ * The function 'func' will be called with a pointer to a monitor
  * as first argument and 'arg' as second argument for each monitor
  * in the tree referred to by 'root'.
  *
@@ -802,7 +805,7 @@ void erts_monitor_tree_delete(ErtsMonitor **root, ErtsMonitor *mon);
  *
  */
 void erts_monitor_tree_foreach(ErtsMonitor *root,
-                               void (*func)(ErtsMonitor *, void *),
+                               ErtsMonitorFunc func,
                                void *arg);
 
 /**
@@ -810,9 +813,10 @@ void erts_monitor_tree_foreach(ErtsMonitor *root,
  * @brief Call a function for each monitor in a monitor tree. Yield
  *        if lots of monitors exist.
  *
- * The funcion 'func' will be called with a pointer to a monitor
+ * The function 'func' will be called with a pointer to a monitor
  * as first argument and 'arg' as second argument for each monitor
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * It is assumed that:
  * - *yspp equals NULL on first call
@@ -835,27 +839,28 @@ void erts_monitor_tree_foreach(ErtsMonitor *root,
  *                              *yspp should be NULL. When done *yspp
  *                              will be NULL.
  *
- * @param[in]     limit         Maximum amount of monitors to process
- *                              before yielding.
+ * @param[in]     reds          Reductions available to execute before yielding.
  *
- * @returns                     A non-zero value when all monitors has been
- *                              processed, and zero when more work is needed.
+ * @returns                     The unconsumed reductions when all monitors
+ *                              have been processed, and zero when more work
+ *                              is needed.
  *
  */
 int erts_monitor_tree_foreach_yielding(ErtsMonitor *root,
-                                       void (*func)(ErtsMonitor *, void *),
+                                       ErtsMonitorFunc func,
                                        void *arg,
                                        void **vyspp,
-                                       Sint limit);
+                                       Sint reds);
 
 /**
  *
  * @brief Delete all monitors from a monitor tree and call a function for
  *        each monitor
  *
- * The funcion 'func' will be called with a pointer to a monitor
+ * The function 'func' will be called with a pointer to a monitor
  * as first argument and 'arg' as second argument for each monitor
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * @param[in,out] root          Pointer to pointer to root of monitor tree
  *
@@ -866,7 +871,7 @@ int erts_monitor_tree_foreach_yielding(ErtsMonitor *root,
  *
  */
 void erts_monitor_tree_foreach_delete(ErtsMonitor **root,
-                                      void (*func)(ErtsMonitor *, void *),
+                                      ErtsMonitorFunc func,
                                       void *arg);
 
 /**
@@ -874,9 +879,10 @@ void erts_monitor_tree_foreach_delete(ErtsMonitor **root,
  * @brief Delete all monitors from a monitor tree and call a function for
  *        each monitor
  *
- * The funcion 'func' will be called with a pointer to a monitor
+ * The function 'func' will be called with a pointer to a monitor
  * as first argument and 'arg' as second argument for each monitor
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * It is assumed that:
  * - *yspp equals NULL on first call
@@ -899,18 +905,18 @@ void erts_monitor_tree_foreach_delete(ErtsMonitor **root,
  *                              *yspp should be NULL. When done *yspp
  *                              will be NULL.
  *
- * @param[in]     limit         Maximum amount of monitors to process
- *                              before yielding.
+ * @param[in]     reds          Reductions available to execute before yielding.
  *
- * @returns                     A non-zero value when all monitors has been
- *                              processed, and zero when more work is needed.
+ * @returns                     The unconsumed reductions when all monitors
+ *                              have been processed, and zero when more work
+ *                              is needed.
  *
  */
 int erts_monitor_tree_foreach_delete_yielding(ErtsMonitor **root,
-                                              void (*func)(ErtsMonitor *, void *),
+                                              ErtsMonitorFunc func,
                                               void *arg,
                                               void **vyspp,
-                                              Sint limit);
+                                              Sint reds);
 
 /*
  * --- Monitor list operations --
@@ -920,7 +926,7 @@ int erts_monitor_tree_foreach_delete_yielding(ErtsMonitor **root,
  *
  * @brief Insert a monitor in a monitor list
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'mon' monitor is not part of any list or tree
  * If the above is not true, bad things will happen.
  *
@@ -935,7 +941,7 @@ ERTS_GLB_INLINE void erts_monitor_list_insert(ErtsMonitor **list, ErtsMonitor *m
  *
  * @brief Delete a monitor from a monitor list
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'mon' monitor is part of the list
  * If the above is not true, bad things will happen.
  *
@@ -980,7 +986,7 @@ ERTS_GLB_INLINE ErtsMonitor *erts_monitor_list_last(ErtsMonitor *list);
  *
  * @brief Call a function for each monitor in a monitor list
  *
- * The funcion 'func' will be called with a pointer to a monitor
+ * The function 'func' will be called with a pointer to a monitor
  * as first argument and 'arg' as second argument for each monitor
  * in the tree referred to by 'list'.
  *
@@ -993,7 +999,7 @@ ERTS_GLB_INLINE ErtsMonitor *erts_monitor_list_last(ErtsMonitor *list);
  *
  */
 void erts_monitor_list_foreach(ErtsMonitor *list,
-                               void (*func)(ErtsMonitor *, void *),
+                               ErtsMonitorFunc func,
                                void *arg);
 
 /**
@@ -1001,9 +1007,10 @@ void erts_monitor_list_foreach(ErtsMonitor *list,
  * @brief Call a function for each monitor in a monitor list. Yield
  *        if lots of monitors exist.
  *
- * The funcion 'func' will be called with a pointer to a monitor
+ * The function 'func' will be called with a pointer to a monitor
  * as first argument and 'arg' as second argument for each monitor
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * It is assumed that:
  * - *yspp equals NULL on first call
@@ -1026,25 +1033,25 @@ void erts_monitor_list_foreach(ErtsMonitor *list,
  *                              *yspp should be NULL. When done *yspp
  *                              will be NULL.
  *
- * @param[in]     limit         Maximum amount of monitors to process
- *                              before yielding.
+ * @param[in]     reds          Reductions available to execute before yielding.
  *
- * @returns                     A non-zero value when all monitors has been
- *                              processed, and zero when more work is needed.
+ * @returns                     The unconsumed reductions when all monitors
+ *                              have been processed, and zero when more work
+ *                              is needed.
  *
  */
 int erts_monitor_list_foreach_yielding(ErtsMonitor *list,
-                                       void (*func)(ErtsMonitor *, void *),
+                                       ErtsMonitorFunc func,
                                        void *arg,
                                        void **vyspp,
-                                       Sint limit);
+                                       Sint reds);
 
 /**
  *
  * @brief Delete all monitors from a monitor list and call a function for
  *        each monitor
  *
- * The funcion 'func' will be called with a pointer to a monitor
+ * The function 'func' will be called with a pointer to a monitor
  * as first argument and 'arg' as second argument for each monitor
  * in the tree referred to by 'root'.
  *
@@ -1057,7 +1064,7 @@ int erts_monitor_list_foreach_yielding(ErtsMonitor *list,
  *
  */
 void erts_monitor_list_foreach_delete(ErtsMonitor **list,
-                                      void (*func)(ErtsMonitor *, void *),
+                                      ErtsMonitorFunc func,
                                       void *arg);
 
 /**
@@ -1065,9 +1072,10 @@ void erts_monitor_list_foreach_delete(ErtsMonitor **list,
  * @brief Delete all monitors from a monitor list and call a function for
  *        each monitor
  *
- * The funcion 'func' will be called with a pointer to a monitor
+ * The function 'func' will be called with a pointer to a monitor
  * as first argument and 'arg' as second argument for each monitor
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * It is assumed that:
  * - *yspp equals NULL on first call
@@ -1090,18 +1098,18 @@ void erts_monitor_list_foreach_delete(ErtsMonitor **list,
  *                              *yspp should be NULL. When done *yspp
  *                              will be NULL.
  *
- * @param[in]     limit         Maximum amount of monitors to process
- *                              before yielding.
+ * @param[in]     reds          Reductions available to execute before yielding.
  *
- * @returns                     A non-zero value when all monitors has been
- *                              processed, and zero when more work is needed.
+ * @returns                     The unconsumed reductions when all monitors
+ *                              have been processed, and zero when more work
+ *                              is needed.
  *
  */
 int erts_monitor_list_foreach_delete_yielding(ErtsMonitor **list,
-                                              void (*func)(ErtsMonitor *, void *),
+                                              ErtsMonitorFunc func,
                                               void *arg,
                                               void **vyspp,
-                                              Sint limit);
+                                              Sint reds);
 
 /*
  * --- Misc monitor operations ---
@@ -1113,7 +1121,7 @@ int erts_monitor_list_foreach_delete_yielding(ErtsMonitor **list,
  *
  * Can create all types of monitors
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'ref' is an internal ordinary reference if type is ERTS_MON_TYPE_PROC,
  *   ERTS_MON_TYPE_PORT, ERTS_MON_TYPE_TIME_OFFSET, or ERTS_MON_TYPE_RESOURCE
  * - 'ref' is NIL if type is ERTS_MON_TYPE_NODE, ERTS_MON_TYPE_NODES, or
@@ -1199,7 +1207,7 @@ ERTS_GLB_INLINE int erts_monitor_is_in_table(ErtsMonitor *mon);
  * When both the origin and the target part of the monitor have
  * been released the monitor structure will be deallocated.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'mon' monitor is not part of any list or tree
  * - 'mon' is not referred to by any other structures
  * If the above are not true, bad things will happen.
@@ -1216,7 +1224,7 @@ ERTS_GLB_INLINE void erts_monitor_release(ErtsMonitor *mon);
  * Release both the origin and target parts of the monitor
  * simultaneously and deallocate the structure.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - Neither the origin part nor the target part of the monitor
  *   are not part of any list or tree
  * - Neither the origin part nor the target part of the monitor
@@ -1232,7 +1240,7 @@ ERTS_GLB_INLINE void erts_monitor_release_both(ErtsMonitorData *mdp);
  *
  * @brief Insert monitor in dist monitor tree or list
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'mon' monitor is not part of any list or tree
  * If the above is not true, bad things will happen.
  *
@@ -1253,7 +1261,7 @@ ERTS_GLB_INLINE int erts_monitor_dist_insert(ErtsMonitor *mon, ErtsMonLnkDist *d
  *
  * @brief Delete monitor from dist monitor tree or list
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'mon' monitor earler has been inserted into 'dist'
  * If the above is not true, bad things will happen.
  *
@@ -1291,7 +1299,7 @@ erts_monitor_set_dead_dist(ErtsMonitor *mon, Eterm nodename);
  * whole size of the monitor data structure is returned; otherwise,
  * half of the size is returned.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'mon' has not been released
  * If the above is not true, bad things will happen.
  *
@@ -1507,6 +1515,8 @@ ERTS_GLB_INLINE ErtsMonitorSuspend *erts_monitor_suspend(ErtsMonitor *mon)
 
 typedef struct ErtsMonLnkNode__ ErtsLink;
 
+typedef int (*ErtsLinkFunc)(ErtsLink *, void *, Sint);
+
 typedef struct {
     ErtsLink a;
     ErtsLink b;
@@ -1544,7 +1554,7 @@ ErtsLink *erts_link_tree_lookup(ErtsLink *root, Eterm item);
  *
  * @brief Lookup or insert a link in a link tree
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' link is not part of any tree or list
  * If the above is not true, bad things will happen.
  *
@@ -1590,7 +1600,7 @@ ErtsLink *erts_link_tree_lookup_create(ErtsLink **root, int *created,
  *
  * @brief Insert a link in a link tree
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - no links with the same key that 'lnk' exist in the tree
  * - 'lnk' is not part of any list of tree
  * If the above are not true, bad things will happen.
@@ -1606,7 +1616,7 @@ void erts_link_tree_insert(ErtsLink **root, ErtsLink *lnk);
  *
  * @brief Replace a link in a link tree
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'old' link and 'new' link have exactly the same key
  * - 'old' link is part of the tree
  * - 'new' link is not part of any tree or list
@@ -1630,7 +1640,7 @@ void erts_link_tree_replace(ErtsLink **root, ErtsLink *old, ErtsLink *new);
  * the tree and 'lnk' has a lower address than the link in the
  * tree, the existing link in the tree is replaced by 'lnk'.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' link is not part of any tree or list
  * If the above are not true, bad things will happen.
  *
@@ -1649,7 +1659,7 @@ ERTS_GLB_INLINE ErtsLink *erts_link_tree_insert_addr_replace(ErtsLink **root,
  *
  * @brief Delete a link from a link tree
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' link is part of the tree
  * If the above is not true, bad things will happen.
  *
@@ -1668,7 +1678,7 @@ void erts_link_tree_delete(ErtsLink **root, ErtsLink *lnk);
  * If link 'lnk' is not in the tree, another link with the same
  * key as 'lnk' is deleted from the tree if such a link exist.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - if 'lnk' link is part of a tree or list, it is part of this tree
  * If the above is not true, bad things will happen.
  *
@@ -1687,7 +1697,7 @@ ERTS_GLB_INLINE ErtsLink *erts_link_tree_key_delete(ErtsLink **root, ErtsLink *l
  *
  * @brief Call a function for each link in a link tree
  *
- * The funcion 'func' will be called with a pointer to a link
+ * The function 'func' will be called with a pointer to a link
  * as first argument and 'arg' as second argument for each link
  * in the tree referred to by 'root'.
  *
@@ -1700,7 +1710,7 @@ ERTS_GLB_INLINE ErtsLink *erts_link_tree_key_delete(ErtsLink **root, ErtsLink *l
  *
  */
 void erts_link_tree_foreach(ErtsLink *root,
-                            void (*func)(ErtsLink *, void *),
+                            ErtsLinkFunc,
                             void *arg);
 
 /**
@@ -1708,9 +1718,10 @@ void erts_link_tree_foreach(ErtsLink *root,
  * @brief Call a function for each link in a link tree. Yield if lots
  *        of links exist.
  *
- * The funcion 'func' will be called with a pointer to a link
+ * The function 'func' will be called with a pointer to a link
  * as first argument and 'arg' as second argument for each link
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * It is assumed that:
  * - *yspp equals NULL on first call
@@ -1733,25 +1744,25 @@ void erts_link_tree_foreach(ErtsLink *root,
  *                              *yspp should be NULL. When done *yspp
  *                              will be NULL.
  *
- * @param[in]     limit         Maximum amount of links to process
- *                              before yielding.
+ * @param[in]     reds          Reductions available to execute before yielding.
  *
- * @returns                     A non-zero value when all links has been
- *                              processed, and zero when more work is needed.
+ * @returns                     The unconsumed reductions when all links
+ *                              have been processed, and zero when more work
+ *                              is needed.
  *
  */
 int erts_link_tree_foreach_yielding(ErtsLink *root,
-                                    void (*func)(ErtsLink *, void *),
+                                    ErtsLinkFunc func,
                                     void *arg,
                                     void **vyspp,
-                                    Sint limit);
+                                    Sint reds);
 
 /**
  *
  * @brief Delete all links from a link tree and call a function for
  *        each link
  *
- * The funcion 'func' will be called with a pointer to a link
+ * The function 'func' will be called with a pointer to a link
  * as first argument and 'arg' as second argument for each link
  * in the tree referred to by 'root'.
  *
@@ -1764,7 +1775,7 @@ int erts_link_tree_foreach_yielding(ErtsLink *root,
  *
  */
 void erts_link_tree_foreach_delete(ErtsLink **root,
-                                   void (*func)(ErtsLink *, void *),
+                                   ErtsLinkFunc func,
                                    void *arg);
 
 /**
@@ -1772,9 +1783,10 @@ void erts_link_tree_foreach_delete(ErtsLink **root,
  * @brief Delete all links from a link tree and call a function for
  *        each link
  *
- * The funcion 'func' will be called with a pointer to a link
+ * The function 'func' will be called with a pointer to a link
  * as first argument and 'arg' as second argument for each link
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * It is assumed that:
  * - *yspp equals NULL on first call
@@ -1797,18 +1809,18 @@ void erts_link_tree_foreach_delete(ErtsLink **root,
  *                              *yspp should be NULL. When done *yspp
  *                              will be NULL.
  *
- * @param[in]     limit         Maximum amount of links to process
- *                              before yielding.
+ * @param[in]     reds          Reductions available to execute before yielding.
  *
- * @returns                     A non-zero value when all links has been
- *                              processed, and zero when more work is needed.
+ * @returns                     The unconsumed reductions when all links
+ *                              have been processed, and zero when more work
+ *                              is needed.
  *
  */
 int erts_link_tree_foreach_delete_yielding(ErtsLink **root,
-                                           void (*func)(ErtsLink *, void *),
+                                           ErtsLinkFunc func,
                                            void *arg,
                                            void **vyspp,
-                                           Sint limit);
+                                           Sint reds);
 
 /* 
  * --- Link list operations ---
@@ -1818,7 +1830,7 @@ int erts_link_tree_foreach_delete_yielding(ErtsLink **root,
  *
  * @brief Insert a link in a link list
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' link is not part of any list or tree
  * If the above is not true, bad things will happen.
  *
@@ -1833,7 +1845,7 @@ ERTS_GLB_INLINE void erts_link_list_insert(ErtsLink **list, ErtsLink *lnk);
  *
  * @brief Delete a link from a link list
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' link is part of the list
  * If the above is not true, bad things will happen.
  *
@@ -1878,7 +1890,7 @@ ERTS_GLB_INLINE ErtsLink *erts_link_list_last(ErtsLink *list);
  *
  * @brief Call a function for each link in a link list
  *
- * The funcion 'func' will be called with a pointer to a link
+ * The function 'func' will be called with a pointer to a link
  * as first argument and 'arg' as second argument for each link
  * in the tree referred to by 'list'.
  *
@@ -1891,7 +1903,7 @@ ERTS_GLB_INLINE ErtsLink *erts_link_list_last(ErtsLink *list);
  *
  */
 void erts_link_list_foreach(ErtsLink *list,
-                            void (*func)(ErtsLink *, void *),
+                            ErtsLinkFunc func,
                             void *arg);
 
 /**
@@ -1899,9 +1911,10 @@ void erts_link_list_foreach(ErtsLink *list,
  * @brief Call a function for each link in a link list. Yield
  *        if lots of links exist.
  *
- * The funcion 'func' will be called with a pointer to a link
+ * The function 'func' will be called with a pointer to a link
  * as first argument and 'arg' as second argument for each link
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * It is assumed that:
  * - *yspp equals NULL on first call
@@ -1924,25 +1937,25 @@ void erts_link_list_foreach(ErtsLink *list,
  *                              *yspp should be NULL. When done *yspp
  *                              will be NULL.
  *
- * @param[in]     limit         Maximum amount of links to process
- *                              before yielding.
+ * @param[in]     reds          Reductions available to execute before yielding.
  *
- * @returns                     A non-zero value when all links has been
- *                              processed, and zero when more work is needed.
+ * @returns                     The unconsumed reductions when all links
+ *                              have been processed, and zero when more work
+ *                              is needed.
  *
  */
 int erts_link_list_foreach_yielding(ErtsLink *list,
-                                    void (*func)(ErtsLink *, void *),
+                                    ErtsLinkFunc func,
                                     void *arg,
                                     void **vyspp,
-                                    Sint limit);
+                                    Sint reds);
 
 /**
  *
  * @brief Delete all links from a link list and call a function for
  *        each link
  *
- * The funcion 'func' will be called with a pointer to a link
+ * The function 'func' will be called with a pointer to a link
  * as first argument and 'arg' as second argument for each link
  * in the tree referred to by 'root'.
  *
@@ -1955,7 +1968,7 @@ int erts_link_list_foreach_yielding(ErtsLink *list,
  *
  */
 void erts_link_list_foreach_delete(ErtsLink **list,
-                                   void (*func)(ErtsLink *, void *),
+                                   ErtsLinkFunc func,
                                    void *arg);
 
 /**
@@ -1963,9 +1976,10 @@ void erts_link_list_foreach_delete(ErtsLink **list,
  * @brief Delete all links from a link list and call a function for
  *        each link
  *
- * The funcion 'func' will be called with a pointer to a link
+ * The function 'func' will be called with a pointer to a link
  * as first argument and 'arg' as second argument for each link
- * in the tree referred to by 'root'.
+ * in the tree referred to by 'root'. It should return the number of
+ * reductions the operator took to perform.
  *
  * It is assumed that:
  * - *yspp equals NULL on first call
@@ -1988,18 +2002,18 @@ void erts_link_list_foreach_delete(ErtsLink **list,
  *                              *yspp should be NULL. When done *yspp
  *                              will be NULL.
  *
- * @param[in]     limit         Maximum amount of links to process
- *                              before yielding.
+ * @param[in]     reds          Reductions available to execute before yielding.
  *
- * @returns                     A non-zero value when all links has been
- *                              processed, and zero when more work is needed.
+ * @returns                     The unconsumed reductions when all links
+ *                              have been processed, and zero when more work
+ *                              is needed.
  *
  */
 int erts_link_list_foreach_delete_yielding(ErtsLink **list,
-                                           void (*func)(ErtsLink *, void *),
+                                           ErtsLinkFunc func,
                                            void *arg,
                                            void **vyspp,
-                                           Sint limit);
+                                           Sint reds);
 
 /*
  * --- Misc link operations ---
@@ -2011,7 +2025,7 @@ int erts_link_list_foreach_delete_yielding(ErtsLink **list,
  *
  * Can create all types of links
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'ref' is an internal ordinary reference if type is ERTS_MON_TYPE_PROC,
  *   ERTS_MON_TYPE_PORT, ERTS_MON_TYPE_TIME_OFFSET, or ERTS_MON_TYPE_RESOURCE
  * - 'ref' is NIL if type is ERTS_MON_TYPE_NODE or ERTS_MON_TYPE_NODES
@@ -2081,7 +2095,7 @@ ERTS_GLB_INLINE int erts_link_is_in_table(ErtsLink *lnk);
  * When both link halves part of the link have been released the link
  * structure will be deallocated.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' link is not part of any list or tree
  * - 'lnk' is not referred to by any other structures
  * If the above are not true, bad things will happen.
@@ -2098,7 +2112,7 @@ ERTS_GLB_INLINE void erts_link_release(ErtsLink *lnk);
  * Release both halves of a link simultaneously and deallocate
  * the structure.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - Neither of the parts of the link are part of any list or tree
  * - Neither of the parts of the link or the link data structure
  *   are referred to by any other structures
@@ -2113,7 +2127,7 @@ ERTS_GLB_INLINE void erts_link_release_both(ErtsLinkData *ldp);
  *
  * @brief Insert link in dist link list
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' link is not part of any list or tree
  * If the above is not true, bad things will happen.
  *
@@ -2134,7 +2148,7 @@ ERTS_GLB_INLINE int erts_link_dist_insert(ErtsLink *lnk, ErtsMonLnkDist *dist);
  *
  * @brief Delete link from dist link list
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' link earler has been inserted into 'dist'
  * If the above is not true, bad things will happen.
  *
@@ -2172,7 +2186,7 @@ erts_link_set_dead_dist(ErtsLink *lnk, Eterm nodename);
  * whole size of the link data structure is returned; otherwise,
  * half of the size is returned.
  *
- * When the funcion is called it is assumed that:
+ * When the function is called it is assumed that:
  * - 'lnk' has not been released
  * If the above is not true, bad things will happen.
  *
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index a48d0391f6..4f317c9b25 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -2357,12 +2357,13 @@ rmon_refc_read(ErtsResourceMonitors *rms)
     return rms->refc & ERTS_RESOURCE_REFC_MASK;
 }
 
-static void dtor_demonitor(ErtsMonitor* mon, void* context)
+static int dtor_demonitor(ErtsMonitor* mon, void* context, Sint reds)
 {
     ASSERT(erts_monitor_is_origin(mon));
     ASSERT(is_internal_pid(mon->other.item));
 
     erts_proc_sig_send_demonitor(mon);
+    return 1;
 }
 
 #  define NIF_RESOURCE_DTOR &nif_resource_dtor
diff --git a/erts/emulator/beam/erl_node_tables.c b/erts/emulator/beam/erl_node_tables.c
index 18ed782ae3..b7dbe625a2 100644
--- a/erts/emulator/beam/erl_node_tables.c
+++ b/erts/emulator/beam/erl_node_tables.c
@@ -1544,16 +1544,18 @@ static void insert_monitor_data(ErtsMonitor *mon, int type, Eterm id)
     mdp->origin.flags |= ERTS_ML_FLG_DBG_VISITED;
 }
 
-static void insert_monitor(ErtsMonitor *mon, void *idp)
+static int insert_monitor(ErtsMonitor *mon, void *idp, Sint reds)
 {
     Eterm id = *((Eterm *) idp);
     insert_monitor_data(mon, MONITOR_REF, id);
+    return 1;
 }
 
-static void clear_visited_monitor(ErtsMonitor *mon, void *p)
+static int clear_visited_monitor(ErtsMonitor *mon, void *p, Sint reds)
 {
     ErtsMonitorData *mdp = erts_monitor_to_data(mon);
     mdp->origin.flags &= ~ERTS_ML_FLG_DBG_VISITED;
+    return 1;
 }
 
 static void
@@ -1621,16 +1623,18 @@ static void insert_link_data(ErtsLink *lnk, int type, Eterm id)
     ldp->a.flags |= ERTS_ML_FLG_DBG_VISITED;
 }
 
-static void insert_link(ErtsLink *lnk, void *idp)
+static int insert_link(ErtsLink *lnk, void *idp, Sint reds)
 {
     Eterm id = *((Eterm *) idp);
     insert_link_data(lnk, LINK_REF, id);
+    return 1;
 }
 
-static void clear_visited_link(ErtsLink *lnk, void *p)
+static int clear_visited_link(ErtsLink *lnk, void *p, Sint reds)
 {
     ErtsLinkData *ldp = erts_link_to_data(lnk);
     ldp->a.flags &= ~ERTS_ML_FLG_DBG_VISITED;
+    return 1;
 }
 
 static void
@@ -1798,18 +1802,20 @@ insert_sig_offheap(ErlOffHeap *ohp, void *arg)
     insert_offheap(ohp, SIGNAL_REF, proc->common.id);
 }
 
-static void
-insert_sig_monitor(ErtsMonitor *mon, void *arg)
+static int
+insert_sig_monitor(ErtsMonitor *mon, void *arg, Sint reds)
 {
     Process *proc = arg;
     insert_monitor_data(mon, SIGNAL_REF, proc->common.id);
+    return 1;
 }
 
-static void
-insert_sig_link(ErtsLink *lnk, void *arg)
+static int
+insert_sig_link(ErtsLink *lnk, void *arg, Sint reds)
 {
     Process *proc = arg;
     insert_link_data(lnk, SIGNAL_REF, proc->common.id);
+    return 1;
 }
 
 static void
diff --git a/erts/emulator/beam/erl_proc_sig_queue.c b/erts/emulator/beam/erl_proc_sig_queue.c
index 18418a76e1..668ee4ce96 100644
--- a/erts/emulator/beam/erl_proc_sig_queue.c
+++ b/erts/emulator/beam/erl_proc_sig_queue.c
@@ -3590,9 +3590,10 @@ stretch_limit(Process *c_p, ErtsSigRecvTracing *tp,
 
 
 int
-erts_proc_sig_handle_exit(Process *c_p, int *redsp)
+erts_proc_sig_handle_exit(Process *c_p, Sint *redsp)
 {
-    int cnt, limit;
+    int cnt;
+    Sint limit;
     ErtsMessage *sig, ***next_nm_sig;
 
     ERTS_HDBG_CHECK_SIGNAL_PRIV_QUEUE(c_p, 0);
@@ -3673,7 +3674,7 @@ erts_proc_sig_handle_exit(Process *c_p, int *redsp)
         case ERTS_SIG_Q_OP_MONITOR: {
             ErtsProcExitContext pectxt = {c_p, am_noproc};
             erts_proc_exit_handle_monitor((ErtsMonitor *) sig,
-                                          (void *) &pectxt);
+                                          (void *) &pectxt, -1);
             cnt += 4;
             break;
         }
@@ -3687,7 +3688,7 @@ erts_proc_sig_handle_exit(Process *c_p, int *redsp)
 
         case ERTS_SIG_Q_OP_LINK: {
             ErtsProcExitContext pectxt = {c_p, am_noproc};
-            erts_proc_exit_handle_link((ErtsLink *) sig, (void *) &pectxt);
+            erts_proc_exit_handle_link((ErtsLink *) sig, (void *) &pectxt, -1);
             break;
         }
 
@@ -4449,8 +4450,8 @@ void
 erts_proc_sig_debug_foreach_sig(Process *c_p,
                                 void (*msg_func)(ErtsMessage *, void *),
                                 void (*oh_func)(ErlOffHeap *, void *),
-                                void (*mon_func)(ErtsMonitor *, void *),
-                                void (*lnk_func)(ErtsLink *, void *),
+                                ErtsMonitorFunc mon_func,
+                                ErtsLinkFunc lnk_func,
                                 void *arg)
 {
     ErtsMessage *queue[] = {c_p->sig_qs.first, c_p->sig_qs.cont, c_p->sig_inq.first};
@@ -4486,13 +4487,13 @@ erts_proc_sig_debug_foreach_sig(Process *c_p,
                     case ERTS_LNK_TYPE_PORT:
                     case ERTS_LNK_TYPE_PROC:
                     case ERTS_LNK_TYPE_DIST_PROC:
-                        lnk_func((ErtsLink *) sig, arg);
+                        lnk_func((ErtsLink *) sig, arg, -1);
                         break;
                     case ERTS_MON_TYPE_PORT:
                     case ERTS_MON_TYPE_PROC:
                     case ERTS_MON_TYPE_DIST_PROC:
                     case ERTS_MON_TYPE_NODE:
-                        mon_func((ErtsMonitor *) sig, arg);
+                        mon_func((ErtsMonitor *) sig, arg, -1);
                         break;
                     default:
                         ERTS_INTERNAL_ERROR("Unexpected sig type");
@@ -4513,7 +4514,7 @@ erts_proc_sig_debug_foreach_sig(Process *c_p,
                     /* Fall through... */
 
                 case ERTS_SIG_Q_OP_MONITOR:
-                    mon_func((ErtsMonitor *) sig, arg);
+                    mon_func((ErtsMonitor *) sig, arg, -1);
                     break;
 
                 case ERTS_SIG_Q_OP_UNLINK:
@@ -4525,7 +4526,7 @@ erts_proc_sig_debug_foreach_sig(Process *c_p,
                     /* Fall through... */
 
                 case ERTS_SIG_Q_OP_LINK:
-                    lnk_func((ErtsLink *) sig, arg);
+                    lnk_func((ErtsLink *) sig, arg, -1);
                     break;
 
                 case ERTS_SIG_Q_OP_GROUP_LEADER: {
diff --git a/erts/emulator/beam/erl_proc_sig_queue.h b/erts/emulator/beam/erl_proc_sig_queue.h
index 6b065a7add..5a02708bb7 100644
--- a/erts/emulator/beam/erl_proc_sig_queue.h
+++ b/erts/emulator/beam/erl_proc_sig_queue.h
@@ -740,7 +740,7 @@ erts_proc_sig_handle_incoming(Process *c_p, erts_aint32_t *statep,
  *                              queue.
  */
 int
-erts_proc_sig_handle_exit(Process *c_p, int *redsp);
+erts_proc_sig_handle_exit(Process *c_p, Sint *redsp);
 
 /**
  *
@@ -970,8 +970,8 @@ void
 erts_proc_sig_debug_foreach_sig(Process *c_p,
                                 void (*msg_func)(ErtsMessage *, void *),
                                 void (*oh_func)(ErlOffHeap *, void *),
-                                void (*mon_func)(ErtsMonitor *, void *),
-                                void (*lnk_func)(ErtsLink *, void *),
+                                ErtsMonitorFunc mon_func,
+                                ErtsLinkFunc lnk_func,
                                 void *arg);
 
 extern Process *erts_dirty_process_signal_handler;
diff --git a/erts/emulator/beam/erl_process.c b/erts/emulator/beam/erl_process.c
index c2799f6612..f9cc85b6d7 100644
--- a/erts/emulator/beam/erl_process.c
+++ b/erts/emulator/beam/erl_process.c
@@ -12055,8 +12055,8 @@ erts_set_self_exiting(Process *c_p, Eterm reason)
         add2runq(enqueue, enq_prio, c_p, state, NULL);
 }
 
-void
-erts_proc_exit_handle_monitor(ErtsMonitor *mon, void *vctxt)
+int
+erts_proc_exit_handle_monitor(ErtsMonitor *mon, void *vctxt, Sint reds)
 {
     Process *c_p = ((ErtsProcExitContext *) vctxt)->c_p;
     Eterm reason = ((ErtsProcExitContext *) vctxt)->reason;
@@ -12215,10 +12215,11 @@ erts_proc_exit_handle_monitor(ErtsMonitor *mon, void *vctxt)
         erts_monitor_release_both(mdp);
     else if (mon)
         erts_monitor_release(mon);
+    return 1;
 }
 
-void
-erts_proc_exit_handle_link(ErtsLink *lnk, void *vctxt)
+int
+erts_proc_exit_handle_link(ErtsLink *lnk, void *vctxt, Sint reds)
 {
     Process *c_p = ((ErtsProcExitContext *) vctxt)->c_p;
     Eterm reason = ((ErtsProcExitContext *) vctxt)->reason;
@@ -12288,6 +12289,7 @@ erts_proc_exit_handle_link(ErtsLink *lnk, void *vctxt)
         erts_link_release_both(ldp);
     else if (lnk)
         erts_link_release(lnk);
+    return 1;
 }
 
 /* this function fishishes a process and propagates exit messages - called
diff --git a/erts/emulator/beam/erl_process.h b/erts/emulator/beam/erl_process.h
index 43937f216c..cdc03cf940 100644
--- a/erts/emulator/beam/erl_process.h
+++ b/erts/emulator/beam/erl_process.h
@@ -1820,8 +1820,8 @@ typedef struct {
     Process *c_p;
     Eterm reason;
 } ErtsProcExitContext;
-void erts_proc_exit_handle_monitor(ErtsMonitor *mon, void *vctxt);
-void erts_proc_exit_handle_link(ErtsLink *lnk, void *vctxt);
+int erts_proc_exit_handle_monitor(ErtsMonitor *mon, void *vctxt, Sint reds);
+int erts_proc_exit_handle_link(ErtsLink *lnk, void *vctxt, Sint reds);
 
 Eterm erts_get_process_priority(erts_aint32_t state);
 Eterm erts_set_process_priority(Process *p, Eterm prio);
diff --git a/erts/emulator/beam/erl_process_dump.c b/erts/emulator/beam/erl_process_dump.c
index 10ea401022..46e460582c 100644
--- a/erts/emulator/beam/erl_process_dump.c
+++ b/erts/emulator/beam/erl_process_dump.c
@@ -100,16 +100,18 @@ erts_deep_process_dump(fmtfn_t to, void *to_arg)
     dump_binaries(to, to_arg, all_binaries);
 }
 
-static void
-monitor_size(ErtsMonitor *mon, void *vsize)
+static int
+monitor_size(ErtsMonitor *mon, void *vsize, Sint reds)
 {
     *((Uint *) vsize) += erts_monitor_size(mon);
+    return 1;
 }
 
-static void
-link_size(ErtsMonitor *lnk, void *vsize)
+static int
+link_size(ErtsMonitor *lnk, void *vsize, Sint reds)
 {
     *((Uint *) vsize) += erts_link_size(lnk);
+    return 1;
 }
 
 Uint erts_process_memory(Process *p, int include_sigs_in_transit)
diff --git a/erts/emulator/beam/erl_rbtree.h b/erts/emulator/beam/erl_rbtree.h
index e50abf5cec..ce401fa7e7 100644
--- a/erts/emulator/beam/erl_rbtree.h
+++ b/erts/emulator/beam/erl_rbtree.h
@@ -161,7 +161,7 @@
  *
  * - void <ERTS_RBT_PREFIX>_rbt_foreach(
  *                         ERTS_RBT_T *tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
  *                         void *arg);
  *         Operate by calling the operator 'op' on each element.
  *         Order is undefined.
@@ -170,7 +170,7 @@
  *
  * - void <ERTS_RBT_PREFIX>_rbt_foreach_destroy(
  *                         ERTS_RBT_T *tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
  *                         void *arg);
  *         Operate by calling the operator 'op' on each element.
  *         Order is undefined. Each element should be destroyed
@@ -180,39 +180,46 @@
  *
  * - int <ERTS_RBT_PREFIX>_rbt_foreach_yielding(
  *                         ERTS_RBT_T *tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
  *                         void *arg,
  *                         <ERTS_RBT_PREFIX>_rbt_yield_state_t *ystate,
- *                         Sint ylimit);
+ *                         Sint reds);
  *         Operate by calling the operator 'op' on each element.
  *         Order is undefined.
  *
- *         Yield when 'ylimit' elements has been processed. True is
- *         returned when yielding, and false is returned when
- *         the whole tree has been processed. The tree should not be
- *         modified until all of it has been processed.
+ *         Yield when 'reds' reductions has been processed. The 'op'
+ *         function return the number of reductions that each element
+ *         took to process. The number of reductions remaining is returned,
+ *         meaning that if 0 is returned, there are more elements to be
+ *         processed. If a value greater than 0 is returned the foreach has
+ *         ended. The tree should not be modified until all of it has been
+ *         processed.
  *
  *         'arg' is passed as argument to 'op'.
  *
  * - int <ERTS_RBT_PREFIX>_rbt_foreach_destroy_yielding(
  *                         ERTS_RBT_T *tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
  *                         void *arg,
  *                         <ERTS_RBT_PREFIX>_rbt_yield_state_t *ystate,
- *                         Sint ylimit);
+ *                         Sint reds);
  *         Operate by calling the operator 'op' on each element.
  *         Order is undefined. Each element should be destroyed
  *         by 'op'.
  *
- *         Yield when 'ylimit' elements has been processed. True is
- *         returned when yielding, and false is returned when
- *         the whole tree has been processed.
+ *         Yield when 'reds' reductions has been processed. The 'op'
+ *         function return the number of reductions that each element
+ *         took to process. The number of reductions remaining is returned,
+ *         meaning that if 0 is returned, there are more elements to be
+ *         processed. If a value greater than 0 is returned the foreach has
+ *         ended. The tree should not be modified until all of it has been
+ *         processed.
  *
  *         'arg' is passed as argument to 'op'.
  *
  * - void <ERTS_RBT_PREFIX>_rbt_foreach_small(
  *                         ERTS_RBT_T *tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
  *                         void *arg);
  *         Operate by calling the operator 'op' on each element from
  *         smallest towards larger elements.
@@ -221,7 +228,7 @@
  *
  * - void <ERTS_RBT_PREFIX>_rbt_foreach_large(
  *                         ERTS_RBT_T *tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
  *                         void *arg);
  *         Operate by calling the operator 'op' on each element from
  *         largest towards smaller elements.
@@ -230,40 +237,46 @@
  *
  * - int <ERTS_RBT_PREFIX>_rbt_foreach_small_yielding(
  *                         ERTS_RBT_T *tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
  *                         void *arg,
  *                         <ERTS_RBT_PREFIX>_rbt_yield_state_t *ystate,
- *                         Sint ylimit);
+ *                         Sint reds);
  *         Operate by calling the operator 'op' on each element from
  *         smallest towards larger elements.
  *
- *         Yield when 'ylimit' elements has been processed. True is
- *         returned when yielding, and false is returned when
- *         the whole tree has been processed. The tree should not be
- *         modified until all of it has been processed.
+ *         Yield when 'reds' reductions has been processed. The 'op'
+ *         function return the number of reductions that each element
+ *         took to process. The number of reductions remaining is returned,
+ *         meaning that if 0 is returned, there are more elements to be
+ *         processed. If a value greater than 0 is returned the foreach has
+ *         ended. The tree should not be modified until all of it has been
+ *         processed.
  *
  *         'arg' is passed as argument to 'op'.
  *
  * - int <ERTS_RBT_PREFIX>_rbt_foreach_large_yielding(
  *                         ERTS_RBT_T *tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
  *                         void *arg,
  *                         <ERTS_RBT_PREFIX>_rbt_yield_state_t *ystate,
- *                         Sint ylimit);
+ *                         Sint reds);
  *         Operate by calling the operator 'op' on each element from
  *         largest towards smaller elements.
  *
- *         Yield when 'ylimit' elements has been processed. True is
- *         returned when yielding, and false is returned when
- *         the whole tree has been processed. The tree should not be
- *         modified until all of it has been processed.
+ *         Yield when 'reds' reductions has been processed. The 'op'
+ *         function return the number of reductions that each element
+ *         took to process. The number of reductions remaining is returned,
+ *         meaning that if 0 is returned, there are more elements to be
+ *         processed. If a value greater than 0 is returned the foreach has
+ *         ended. The tree should not be modified until all of it has been
+ *         processed.
  *
  *         'arg' is passed as argument to 'op'.
  *
  * - void <ERTS_RBT_PREFIX>_rbt_foreach_small_destroy(
  *                         ERTS_RBT_T **tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
- *                         void (*destr)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
+ *                         int (*destr)(ERTS_RBT_T *, void *),
  *                         void *arg);
  *         Operate by calling the operator 'op' on each element from
  *         smallest towards larger elements.
@@ -277,8 +290,8 @@
  *
  * - void <ERTS_RBT_PREFIX>_rbt_foreach_large_destroy(
  *                         ERTS_RBT_T **tree,
- *                         void (*op)(ERTS_RBT_T *, void *),
- *                         void (*destr)(ERTS_RBT_T *, void *),
+ *                         int (*op)(ERTS_RBT_T *, void *),
+ *                         int (*destr)(ERTS_RBT_T *, void *),
  *                         void *arg);
  *         Operate by calling the operator 'op' on each element from
  *         largest towards smaller elements.
@@ -292,11 +305,11 @@
  *
  * - int <ERTS_RBT_PREFIX>_rbt_foreach_small_destroy_yielding(
  *                        ERTS_RBT_T **tree,
- *                        void (*op)(ERTS_RBT_T *, void *),
- *                        void (*destr)(ERTS_RBT_T *, void *),
+ *                        int (*op)(ERTS_RBT_T *, void *),
+ *                        int (*destr)(ERTS_RBT_T *, void *),
  *                        void *arg,
  *                        <ERTS_RBT_PREFIX>_rbt_yield_state_t *ystate,
- *                        Sint ylimit);
+ *                        Sint reds);
  *         Operate by calling the operator 'op' on each element from
  *         smallest towards larger elements.
  *
@@ -305,20 +318,23 @@
  *         Note that elements are often destroyed in another order
  *         than the order that the elements are operated on.
  *
- *         Yield when 'ylimit' elements has been processed. True is
- *         returned when yielding, and false is returned when
- *         the whole tree has been processed. The tree should not be
- *         modified until all of it has been processed.
+ *         Yield when 'reds' reductions has been processed. The 'op' and
+ *         'destr' functions return the number of reductions that each element
+ *         took to process. The number of reductions remaining is returned,
+ *         meaning that if 0 is returned, there are more elements to be
+ *         processed. If a value greater than 0 is returned the foreach has
+ *         ended. The tree should not be modified until all of it has been
+ *         processed.
  *
  *         'arg' is passed as argument to 'op' and 'destroy'.
  *
  * - int <ERTS_RBT_PREFIX>_rbt_foreach_large_destroy_yielding(
  *                        ERTS_RBT_T **tree,
- *                        void (*op)(ERTS_RBT_T *, void *),
- *                        void (*destr)(ERTS_RBT_T *, void *),
+ *                        int (*op)(ERTS_RBT_T *, void *),
+ *                        int (*destr)(ERTS_RBT_T *, void *),
  *                        void *arg,
  *                        <ERTS_RBT_PREFIX>_rbt_yield_state_t *ystate,
- *                        Sint ylimit);
+ *                        Sint reds);
  *         Operate by calling the operator 'op' on each element from
  *         largest towards smaller elements.
  *
@@ -327,10 +343,13 @@
  *         Note that elements are often destroyed in another order
  *         than the order that the elements are operated on.
  *
- *         Yield when 'ylimit' elements has been processed. True is
- *         returned when yielding, and false is returned when
- *         the whole tree has been processed. The tree should not be
- *         modified until all of it has been processed.
+ *         Yield when 'reds' reductions has been processed. The 'op' and
+ *         'destr' functions return the number of reductions that each element
+ *         took to process. The number of reductions remaining is returned,
+ *         meaning that if 0 is returned, there are more elements to be
+ *         processed. If a value greater than 0 is returned the foreach has
+ *         ended. The tree should not be modified until all of it has been
+ *         processed.
  *
  *         'arg' is passed as argument to 'op' and 'destroy'.
  *
@@ -447,17 +466,6 @@
 #  define ERTS_RBT_API_INLINE__ ERTS_INLINE
 #endif
 
-#ifndef ERTS_RBT_YIELD_STAT_INITER
-#  define ERTS_RBT_YIELD_STAT_INITER {NULL, 0}
-#endif
-#ifndef ERTS_RBT_YIELD_STAT_INIT
-#  define ERTS_RBT_YIELD_STAT_INIT(YS) \
-    do {                               \
-        (YS)->x = NULL;                \
-        (YS)->up = 0;                  \
-    } while (0)
-#endif
-
 #define ERTS_RBT_CONCAT_MACRO_VALUES___(X, Y) \
     X ## Y
 #define ERTS_RBT_CONCAT_MACRO_VALUES__(X, Y) \
@@ -470,8 +478,38 @@
 typedef struct {
     ERTS_RBT_T *x;
     int up;
+#ifdef DEBUG
+    int debug_red_adj;
+#endif
 } ERTS_RBT_YIELD_STATE_T__;
 
+#define ERTS_RBT_CALLBACK_FOREACH_FUNC(NAME) int (*NAME)(ERTS_RBT_T *, void *, Sint)
+
+#ifndef ERTS_RBT_YIELD_STAT_INITER
+#  ifdef DEBUG
+#    define ERTS_RBT_YIELD_STAT_INITER {NULL, 0, CONTEXT_REDS}
+#  else
+#    define ERTS_RBT_YIELD_STAT_INITER {NULL, 0}
+#  endif
+#endif
+#ifndef ERTS_RBT_YIELD_STAT_INIT
+#  define ERTS_RBT_YIELD_STAT_INIT__(YS)                                \
+    do {                                                                \
+        (YS)->x = NULL;                                                 \
+        (YS)->up = 0;                                                   \
+    } while (0)
+#  ifdef DEBUG
+#    define ERTS_RBT_YIELD_STAT_INIT(YS)        \
+    do {                                        \
+        ERTS_RBT_YIELD_STAT_INIT__(YS);         \
+        (YS)->debug_red_adj = CONTEXT_REDS;     \
+    } while(0)
+#  else
+#    define ERTS_RBT_YIELD_STAT_INIT(YS) ERTS_RBT_YIELD_STAT_INIT__(YS)
+#  endif
+#endif
+
+
 #define ERTS_RBT_FUNC__(Name) \
     ERTS_RBT_CONCAT_MACRO_VALUES__(ERTS_RBT_PREFIX, _rbt_ ## Name)
 
@@ -1302,11 +1340,11 @@ ERTS_RBT_FUNC__(largest)(ERTS_RBT_T *root)
 static ERTS_INLINE int
 ERTS_RBT_FUNC__(foreach_unordered__)(ERTS_RBT_T **root,
 				     int destroying,
-				     void (*op)(ERTS_RBT_T *, void *),
+				     ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 				     void *arg,
-				     int yielding,
+                                     int yielding,
 				     ERTS_RBT_YIELD_STATE_T__ *ystate,
-				     Sint ylimit)
+				     Sint reds)
 {
     ERTS_RBT_T *c, *p, *x;
 
@@ -1314,13 +1352,17 @@ ERTS_RBT_FUNC__(foreach_unordered__)(ERTS_RBT_T **root,
 
     if (yielding && ystate->x) {
 	x = ystate->x;
+#ifdef DEBUG
+        if (ystate->debug_red_adj > 0)
+            ystate->debug_red_adj -= 100;
+#endif
 	ERTS_RBT_ASSERT(ystate->up);
 	goto restart_up;
     }
     else {
 	x = *root;
 	if (!x)
-	    return 0;
+	    return reds;
 	if (destroying)
 	    *root = NULL;
     }
@@ -1346,10 +1388,10 @@ ERTS_RBT_FUNC__(foreach_unordered__)(ERTS_RBT_T **root,
 #ifdef ERTS_RBT_DEBUG
 	    int cdir;
 #endif
-	    if (yielding && ylimit-- <= 0) {
+	    if (yielding && reds <= 0) {
 		ystate->x = x;
 		ystate->up = 1;
-		return 1;
+		return 0;
 	    }
 
 	restart_up:
@@ -1375,14 +1417,20 @@ ERTS_RBT_FUNC__(foreach_unordered__)(ERTS_RBT_T **root,
 	    }
 #endif
 
-	    (*op)(x, arg);
+            reds -= (*op)(x, arg, reds);
+#ifdef DEBUG
+            if (yielding)
+                reds -= ystate->debug_red_adj;
+#endif
 
 	    if (!p) {
+                /* Done */
 		if (yielding) {
 		    ystate->x = NULL;
 		    ystate->up = 0;
+                    return reds <= 0 ? 1 : reds;
 		}
-		return 0; /* Done */
+                return 1;
 	    }
 
 	    c = ERTS_RBT_GET_RIGHT(p);
@@ -1407,20 +1455,26 @@ static ERTS_INLINE int
 ERTS_RBT_FUNC__(foreach_ordered__)(ERTS_RBT_T **root,
 				   int from_small,
 				   int destroying,
-				   void (*op)(ERTS_RBT_T *, void *),
-				   void (*destroy)(ERTS_RBT_T *, void *),
+                                   ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
+                                   ERTS_RBT_CALLBACK_FOREACH_FUNC(destroy),
 				   void *arg,
-				   int yielding,
+                                   int yielding,
 				   ERTS_RBT_YIELD_STATE_T__ *ystate,
-				   Sint ylimit)
+				   Sint reds)
 {
     ERTS_RBT_T *c, *p, *x;
 
     ERTS_RBT_ASSERT(!yielding || ystate);
     ERTS_RBT_ASSERT(!destroying || destroy);
+    ERTS_RBT_ASSERT(!yielding || yop);
+    ERTS_RBT_ASSERT(yielding || op);
 
     if (yielding && ystate->x) {
 	x = ystate->x;
+#ifdef DEBUG
+        if (ystate->debug_red_adj > 0)
+            ystate->debug_red_adj -= 100;
+#endif
 	if (ystate->up)
 	    goto restart_up;
 	else
@@ -1429,7 +1483,7 @@ ERTS_RBT_FUNC__(foreach_ordered__)(ERTS_RBT_T **root,
     else {
 	x = *root;
 	if (!x)
-	    return 0;
+	    return reds;
 	if (destroying)
 	    *root = NULL;
     }
@@ -1445,12 +1499,16 @@ ERTS_RBT_FUNC__(foreach_ordered__)(ERTS_RBT_T **root,
 		x = c;
 	    }
 
-	    (*op)(x, arg);
+            reds -= (*op)(x, arg, reds);
+#ifdef DEBUG
+            if (yielding)
+                reds -= ystate->debug_red_adj;
+#endif
 
-	    if (yielding && --ylimit <= 0) {
+	    if (yielding && reds <= 0) {
 		ystate->x = x;
 		ystate->up = 0;
-		return 1;
+		return 0;
 	    }
 
 	restart_down:
@@ -1472,12 +1530,16 @@ ERTS_RBT_FUNC__(foreach_ordered__)(ERTS_RBT_T **root,
 				     ? ERTS_RBT_GET_LEFT(p)
 				     : ERTS_RBT_GET_RIGHT(p)) == x);
 
-		    (*op)(p, arg);
+                    reds -= (*op)(p, arg, reds);
+#ifdef DEBUG
+                    if (yielding)
+                        reds -= ystate->debug_red_adj;
+#endif
 
-		    if (yielding && --ylimit <= 0) {
+		    if (yielding && reds <= 0) {
 			ystate->x = x;
 			ystate->up = 1;
-			return 1;
+			return 0;
 		    restart_up:
 			p = ERTS_RBT_GET_PARENT(x);
 		    }
@@ -1510,15 +1572,20 @@ ERTS_RBT_FUNC__(foreach_ordered__)(ERTS_RBT_T **root,
 		}
 #endif
 
-		(*destroy)(x, arg);
+		reds -= (*destroy)(x, arg, reds);
+#ifdef DEBUG
+                if (yielding)
+                    reds -= ystate->debug_red_adj;
+#endif
 	    }
 
 	    if (!p) {
 		if (yielding) {
 		    ystate->x = NULL;
 		    ystate->up = 0;
+                    return reds <= 0 ? 1 : reds;
 		}
-		return 0; /* Done */
+		return 1; /* Done */
 	    }
 	    x = p;
 	}
@@ -1531,7 +1598,7 @@ ERTS_RBT_FUNC__(foreach_ordered__)(ERTS_RBT_T **root,
 
 static ERTS_RBT_API_INLINE__ void
 ERTS_RBT_FUNC__(foreach)(ERTS_RBT_T *root,
-			 void (*op)(ERTS_RBT_T *, void *),
+			 ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 			 void *arg)
 {
     (void) ERTS_RBT_FUNC__(foreach_unordered__)(&root, 0, op, arg,
@@ -1544,7 +1611,7 @@ ERTS_RBT_FUNC__(foreach)(ERTS_RBT_T *root,
 
 static ERTS_RBT_API_INLINE__ void
 ERTS_RBT_FUNC__(foreach_small)(ERTS_RBT_T *root,
-			       void (*op)(ERTS_RBT_T *, void *),
+			       ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 			       void *arg)
 {
     (void) ERTS_RBT_FUNC__(foreach_ordered__)(&root, 1, 0,
@@ -1558,7 +1625,7 @@ ERTS_RBT_FUNC__(foreach_small)(ERTS_RBT_T *root,
 
 static ERTS_RBT_API_INLINE__ void
 ERTS_RBT_FUNC__(foreach_large)(ERTS_RBT_T *root,
-			       void (*op)(ERTS_RBT_T *, void *),
+			       ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 			       void *arg)
 {
     (void) ERTS_RBT_FUNC__(foreach_ordered__)(&root, 0, 0,
@@ -1572,13 +1639,13 @@ ERTS_RBT_FUNC__(foreach_large)(ERTS_RBT_T *root,
 
 static ERTS_RBT_API_INLINE__ int
 ERTS_RBT_FUNC__(foreach_yielding)(ERTS_RBT_T *root,
-				  void (*op)(ERTS_RBT_T *, void *),
+				  ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 				  void *arg,
 				  ERTS_RBT_YIELD_STATE_T__ *ystate,
-				  Sint ylimit)
+				  Sint reds)
 {
     return ERTS_RBT_FUNC__(foreach_unordered__)(&root, 0, op, arg,
-						1, ystate, ylimit);
+						1, ystate, reds);
 }
 
 #endif /* ERTS_RBT_WANT_FOREACH_YIELDING */
@@ -1587,14 +1654,14 @@ ERTS_RBT_FUNC__(foreach_yielding)(ERTS_RBT_T *root,
 
 static ERTS_RBT_API_INLINE__ int
 ERTS_RBT_FUNC__(foreach_small_yielding)(ERTS_RBT_T *root,
-					void (*op)(ERTS_RBT_T *, void *),
+					ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 					void *arg,
 					ERTS_RBT_YIELD_STATE_T__ *ystate,
-					Sint ylimit)
+					Sint reds)
 {
     return ERTS_RBT_FUNC__(foreach_ordered__)(&root, 1, 0,
 					      op, NULL, arg,
-					      1, ystate, ylimit);
+					      1, ystate, reds);
 }
 
 #endif /* ERTS_RBT_WANT_FOREACH_SMALL_YIELDING */
@@ -1603,14 +1670,14 @@ ERTS_RBT_FUNC__(foreach_small_yielding)(ERTS_RBT_T *root,
 
 static ERTS_RBT_API_INLINE__ int
 ERTS_RBT_FUNC__(foreach_large_yielding)(ERTS_RBT_T *root,
-					void (*op)(ERTS_RBT_T *, void *),
+					ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 					void *arg,
 					ERTS_RBT_YIELD_STATE_T__ *ystate,
-					Sint ylimit)
+					Sint reds)
 {
     return ERTS_RBT_FUNC__(foreach_ordered__)(&root, 0, 0,
 					      op, NULL, arg,
-					      1, ystate, ylimit);
+					      1, ystate, reds);
 }
 
 #endif /* ERTS_RBT_WANT_FOREACH_LARGE_YIELDING */
@@ -1619,11 +1686,11 @@ ERTS_RBT_FUNC__(foreach_large_yielding)(ERTS_RBT_T *root,
 
 static ERTS_RBT_API_INLINE__ void
 ERTS_RBT_FUNC__(foreach_destroy)(ERTS_RBT_T **root,
-				 void (*op)(ERTS_RBT_T *, void *),
+				 ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 				 void *arg)
 {
     (void) ERTS_RBT_FUNC__(foreach_unordered__)(root, 1, op, arg,
-						0, NULL, 0);
+                                                0, NULL, 0);
 }
 
 #endif /* ERTS_RBT_WANT_FOREACH_DESTROY */
@@ -1632,8 +1699,8 @@ ERTS_RBT_FUNC__(foreach_destroy)(ERTS_RBT_T **root,
 
 static ERTS_RBT_API_INLINE__ void
 ERTS_RBT_FUNC__(foreach_small_destroy)(ERTS_RBT_T **root,
-				       void (*op)(ERTS_RBT_T *, void *),
-				       void (*destr)(ERTS_RBT_T *, void *),
+				       ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
+				       ERTS_RBT_CALLBACK_FOREACH_FUNC(destr),
 				       void *arg)
 {
     (void) ERTS_RBT_FUNC__(foreach_ordered__)(root, 1, 1,
@@ -1647,8 +1714,8 @@ ERTS_RBT_FUNC__(foreach_small_destroy)(ERTS_RBT_T **root,
 
 static ERTS_RBT_API_INLINE__ void
 ERTS_RBT_FUNC__(foreach_large_destroy)(ERTS_RBT_T **root,
-				       void (*op)(ERTS_RBT_T *, void *),
-				       void (*destr)(ERTS_RBT_T *, void *),
+				       ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
+				       ERTS_RBT_CALLBACK_FOREACH_FUNC(destr),
 				       void *arg)
 {
     (void) ERTS_RBT_FUNC__(foreach_ordered__)(root, 0, 1,
@@ -1662,13 +1729,13 @@ ERTS_RBT_FUNC__(foreach_large_destroy)(ERTS_RBT_T **root,
 
 static ERTS_RBT_API_INLINE__ int
 ERTS_RBT_FUNC__(foreach_destroy_yielding)(ERTS_RBT_T **root,
-					  void (*op)(ERTS_RBT_T *, void *),
+					  ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
 					  void *arg,
 					  ERTS_RBT_YIELD_STATE_T__ *ystate,
-					  Sint ylimit)
+					  Sint reds)
 {
     return ERTS_RBT_FUNC__(foreach_unordered__)(root, 1, op, arg,
-						1, ystate, ylimit);
+						1, ystate, reds);
 }
 
 #endif /* ERTS_RBT_WANT_FOREACH_DESTROY_YIELDING */
@@ -1677,15 +1744,15 @@ ERTS_RBT_FUNC__(foreach_destroy_yielding)(ERTS_RBT_T **root,
 
 static ERTS_RBT_API_INLINE__ int
 ERTS_RBT_FUNC__(foreach_small_destroy_yielding)(ERTS_RBT_T **root,
-						void (*op)(ERTS_RBT_T *, void *),
-						void (*destr)(ERTS_RBT_T *, void *),
+						ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
+						ERTS_RBT_CALLBACK_FOREACH_FUNC(destr),
 						void *arg,
 						ERTS_RBT_YIELD_STATE_T__ *ystate,
-						Sint ylimit)
+						Sint reds)
 {
     return ERTS_RBT_FUNC__(foreach_ordered__)(root, 1, 1,
 					      op, destr, arg,
-					      1, ystate, ylimit);
+					      1, ystate, reds);
 }
 
 #endif /* ERTS_RBT_WANT_FOREACH_SMALL_DESTROY_YIELDING */
@@ -1694,15 +1761,15 @@ ERTS_RBT_FUNC__(foreach_small_destroy_yielding)(ERTS_RBT_T **root,
 
 static ERTS_RBT_API_INLINE__ int
 ERTS_RBT_FUNC__(foreach_large_destroy_yielding)(ERTS_RBT_T **root,
-						void (*op)(ERTS_RBT_T *, void *),
-						void (*destr)(ERTS_RBT_T *, void *),
+						ERTS_RBT_CALLBACK_FOREACH_FUNC(op),
+						ERTS_RBT_CALLBACK_FOREACH_FUNC(destr),
 						void *arg,
 						ERTS_RBT_YIELD_STATE_T__ *ystate,
-						Sint ylimit)
+						Sint reds)
 {
     return ERTS_RBT_FUNC__(foreach_ordered__)(root, 0, 1,
 					      op, destr, arg,
-					      1, ystate, ylimit);
+					      1, ystate, reds);
 }
 
 #endif /* ERTS_RBT_WANT_FOREACH_LARGE_DESTROY_YIELDING */
@@ -1855,6 +1922,7 @@ ERTS_RBT_FUNC__(hdbg_check_tree)(ERTS_RBT_T *root, ERTS_RBT_T *n)
 #ifdef ERTS_RBT_UNDEF
 #  undef ERTS_RBT_PREFIX
 #  undef ERTS_RBT_T
+#  undef ERTS_RBT_CALLBACK_FOREACH_FUNC
 #  undef ERTS_RBT_KEY_T
 #  undef ERTS_RBT_FLAGS_T
 #  undef ERTS_RBT_INIT_EMPTY_TNODE
diff --git a/erts/emulator/beam/erl_time_sup.c b/erts/emulator/beam/erl_time_sup.c
index 29c698e34f..d26ea19494 100644
--- a/erts/emulator/beam/erl_time_sup.c
+++ b/erts/emulator/beam/erl_time_sup.c
@@ -1911,8 +1911,8 @@ typedef struct {
     ErtsTimeOffsetMonitorInfo *to_mon_info;
 } ErtsTimeOffsetMonitorContext;
 
-static void
-save_time_offset_monitor(ErtsMonitor *mon, void *vcntxt)
+static int
+save_time_offset_monitor(ErtsMonitor *mon, void *vcntxt, Sint reds)
 {
     ErtsTimeOffsetMonitorContext *cntxt;
     ErtsMonitorData *mdp = erts_monitor_to_data(mon);
@@ -1935,7 +1935,7 @@ save_time_offset_monitor(ErtsMonitor *mon, void *vcntxt)
 
     cntxt->to_mon_info[mix].ref
 	= make_internal_ref(&cntxt->to_mon_info[mix].heap[0]);
-
+    return 1;
 }
 
 static void
diff --git a/erts/emulator/beam/io.c b/erts/emulator/beam/io.c
index 7322239a73..6a2be52e11 100644
--- a/erts/emulator/beam/io.c
+++ b/erts/emulator/beam/io.c
@@ -3644,20 +3644,22 @@ typedef struct {
     Eterm reason;
 } ErtsPortExitContext;
 
-static void link_port_exit(ErtsLink *lnk, void *vpectxt)
+static int link_port_exit(ErtsLink *lnk, void *vpectxt, Sint reds)
 {
     ErtsPortExitContext *pectxt = vpectxt;
     erts_proc_sig_send_link_exit(NULL, pectxt->port_id,
                                  lnk, pectxt->reason, NIL);
+    return 1;
 }
 
-static void monitor_port_exit(ErtsMonitor *mon, void *vpectxt)
+static int monitor_port_exit(ErtsMonitor *mon, void *vpectxt, Sint reds)
 {
     ErtsPortExitContext *pectxt = vpectxt;
     if (erts_monitor_is_target(mon))
         erts_proc_sig_send_monitor_down(mon, pectxt->reason);
     else
         erts_proc_sig_send_demonitor(mon);
+    return 1;
 }
 
 /* 'from' is sending 'this_port' an exit signal, (this_port must be internal).
@@ -4836,7 +4838,7 @@ typedef struct {
     void *arg;
 } prt_one_lnk_data;
 
-static void prt_one_monitor(ErtsMonitor *mon, void *vprtd)
+static int prt_one_monitor(ErtsMonitor *mon, void *vprtd, Sint reds)
 {
     ErtsMonitorData *mdp = erts_monitor_to_data(mon);
     prt_one_lnk_data *prtd = (prt_one_lnk_data *) vprtd;
@@ -4844,12 +4846,14 @@ static void prt_one_monitor(ErtsMonitor *mon, void *vprtd)
         erts_print(prtd->to, prtd->arg, "(%p,%T)", mon->other.ptr, mdp->ref);
     else
         erts_print(prtd->to, prtd->arg, "(%T,%T)", mon->other.item, mdp->ref);
+    return 1;
 }
 
-static void prt_one_lnk(ErtsLink *lnk, void *vprtd)
+static int prt_one_lnk(ErtsLink *lnk, void *vprtd, Sint reds)
 {
     prt_one_lnk_data *prtd = (prt_one_lnk_data *) vprtd;
     erts_print(prtd->to, prtd->arg, "%T", lnk->other.item);
+    return 1;
 }
 
 static void dump_port_state(fmtfn_t to, void *arg, erts_aint32_t state)
diff --git a/erts/emulator/sys/common/erl_osenv.c b/erts/emulator/sys/common/erl_osenv.c
index 6a16377736..f055c5f854 100644
--- a/erts/emulator/sys/common/erl_osenv.c
+++ b/erts/emulator/sys/common/erl_osenv.c
@@ -167,9 +167,10 @@ void erts_osenv_init(erts_osenv_t *env) {
     env->tree = NULL;
 }
 
-static void destroy_foreach(env_rbtnode_t *node, void *_state) {
+static int destroy_foreach(env_rbtnode_t *node, void *_state, Sint reds) {
     erts_free(ERTS_ALC_T_ENVIRONMENT, node);
     (void)_state;
+    return 1;
 }
 
 void erts_osenv_clear(erts_osenv_t *env) {
@@ -182,7 +183,7 @@ struct __env_merge {
     erts_osenv_t *env;
 };
 
-static void merge_foreach(env_rbtnode_t *node, void *_state) {
+static int merge_foreach(env_rbtnode_t *node, void *_state, Sint reds) {
     struct __env_merge *state = (struct __env_merge*)(_state);
     env_rbtnode_t *existing_node;
 
@@ -191,6 +192,7 @@ static void merge_foreach(env_rbtnode_t *node, void *_state) {
     if(existing_node == NULL || state->overwrite_existing) {
         erts_osenv_put_native(state->env, &node->key, &node->value);
     }
+    return 1;
 }
 
 void erts_osenv_merge(erts_osenv_t *env, const erts_osenv_t *with, int overwrite) {
@@ -208,7 +210,7 @@ struct __env_foreach_term {
     void *user_state;
 };
 
-static void foreach_term_wrapper(env_rbtnode_t *node, void *_state) {
+static int foreach_term_wrapper(env_rbtnode_t *node, void *_state, Sint reds) {
     struct __env_foreach_term *state = (struct __env_foreach_term*)_state;
     Eterm key, value;
 
@@ -218,6 +220,7 @@ static void foreach_term_wrapper(env_rbtnode_t *node, void *_state) {
         node->value.length, (byte*)node->value.data);
 
     state->user_callback(state->process, state->user_state, key, value);
+    return 1;
 }
 
 void erts_osenv_foreach_term(const erts_osenv_t *env, struct process *process,
@@ -314,10 +317,11 @@ struct __env_foreach_native {
     void *user_state;
 };
 
-static void foreach_native_wrapper(env_rbtnode_t *node, void *_state) {
+static int foreach_native_wrapper(env_rbtnode_t *node, void *_state, Sint reds) {
     struct __env_foreach_native *state = (struct __env_foreach_native*)_state;
 
     state->user_callback(state->user_state, &node->key, &node->value);
+    return 1;
 }
 
 void erts_osenv_foreach_native(const erts_osenv_t *env, void *state,