[erts] Ensure cleanup of alias table on alias destruction

Author: rickard-green

erts/emulator/beam/erl_bif_info.c

@@ -4149,6 +4149,16 @@ BIF_RETTYPE erts_debug_get_internal_state_1(BIF_ALIST_1)
         else if (ERTS_IS_ATOM_STR("persistent_term", BIF_ARG_1)) {
             BIF_RET(erts_debug_persistent_term_xtra_info(BIF_P));
         }
+        else if (ERTS_IS_ATOM_STR("pid_ref_table_size", BIF_ARG_1)) {
+            Uint size = erts_pid_ref_table_size();
+	    if (IS_SSMALL(size))
+		BIF_RET(make_small(size));
+	    else {
+		Uint hsz = BIG_UWORD_HEAP_SIZE(size);
+		Eterm *hp = HAlloc(BIF_P, hsz);
+		BIF_RET(uword_to_big(size, hp));
+	    }
+        }
     }
     else if (is_tuple(BIF_ARG_1)) {
 	Eterm* tp = tuple_val(BIF_ARG_1);

erts/emulator/beam/erl_bif_unique.c

@@ -701,6 +701,27 @@ init_pid_ref_tables(void)
     }
 }
 
+
+Uint
+erts_pid_ref_table_size(void)
+{
+    int i;
+    Uint sz = 0;
+
+    for (i = 0; i <= erts_no_schedulers; i++) {
+        HashInfo hi;
+	ErtsPidRefTable *tblp = &pid_ref_table[i].u.table;
+        erts_rwmtx_rlock(&tblp->rwmtx);
+        hash_get_info(&hi, &tblp->hash);
+        erts_rwmtx_runlock(&tblp->rwmtx);
+        sz += (Uint) hi.objs;
+    }
+
+    return sz;
+}
+
+
+
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\
  * Unique Integer                                                    *
 \*                                                                   */

erts/emulator/beam/erl_bif_unique.h

@@ -42,7 +42,7 @@ void erts_magic_ref_save_bin__(Eterm ref);
 ErtsMagicBinary *erts_magic_ref_lookup_bin__(Uint32 refn[ERTS_REF_NUMBERS]);
 void erts_pid_ref_delete(Eterm ref);
 Eterm erts_pid_ref_lookup__(Uint32 refn[ERTS_REF_NUMBERS]);
-
+Uint erts_pid_ref_table_size(void);
 
 /* strict monotonic counter */
 

erts/emulator/beam/erl_monitor_link.c

@@ -1094,6 +1094,16 @@ erts_monitor_destroy__(ErtsMonitorData *mdp)
                    || ((mdp->origin.flags & ERTS_ML_FLGS_SAME)
                        == (mdp->u.target.flags & ERTS_ML_FLGS_SAME)));
 
+    if (mdp->origin.flags & ERTS_ML_STATE_ALIAS_MASK) {
+        ASSERT(mdp->origin.type == ERTS_MON_TYPE_ALIAS
+               || mdp->origin.type == ERTS_MON_TYPE_PROC
+               || mdp->origin.type == ERTS_MON_TYPE_PORT
+               || mdp->origin.type == ERTS_MON_TYPE_TIME_OFFSET
+               || mdp->origin.type == ERTS_MON_TYPE_DIST_PROC
+               || mdp->origin.type == ERTS_MON_TYPE_DIST_PORT);
+        erts_pid_ref_delete(mdp->ref);
+    }
+
     switch (mdp->origin.type) {
     case ERTS_MON_TYPE_ALIAS:
         ERTS_ML_ASSERT(!(mdp->origin.flags & ERTS_ML_FLG_TAG));

erts/emulator/test/process_SUITE.erl

@@ -81,6 +81,7 @@
          alias_bif/1,
          monitor_alias/1,
          spawn_monitor_alias/1,
+         alias_process_exit/1,
          monitor_tag/1]).
 
 -export([prio_server/2, prio_client/2, init/1, handle_event/2]).
@@ -149,7 +150,7 @@ groups() ->
        gc_request_when_gc_disabled, gc_request_blast_when_gc_disabled,
        otp_16436, otp_16642]},
      {alias, [],
-      [alias_bif, monitor_alias, spawn_monitor_alias]}].
+      [alias_bif, monitor_alias, spawn_monitor_alias, alias_process_exit]}].
 
 init_per_suite(Config) ->
     A0 = case application:start(sasl) of
@@ -168,9 +169,15 @@ end_per_suite(Config) ->
     catch erts_debug:set_internal_state(available_internal_state, false),
     Config.
 
+init_per_group(alias, Config) ->
+    erts_debug:set_internal_state(available_internal_state, true),
+    Config;
 init_per_group(_GroupName, Config) ->
     Config.
 
+end_per_group(alias, Config) ->
+    erts_debug:set_internal_state(available_internal_state, false),
+    Config;
 end_per_group(_GroupName, Config) ->
     Config.
 
@@ -4032,11 +4039,25 @@ otp_16642(Config) when is_list(Config) ->
     false = is_process_alive(Pid),
     ok.
 
+pid_ref_table_size() ->
+    erts_debug:get_internal_state(pid_ref_table_size).
+
+check_pid_ref_table_size(PRTSz) ->
+    receive after 500 -> ok end,
+    case pid_ref_table_size() of
+        PRTSz ->
+            ok;
+        NewPRTSz ->
+            ct:fail({port_ref_table_size_mismatch, PRTSz, NewPRTSz})
+    end.
+
 alias_bif(Config) when is_list(Config) ->
+    PRTSz = pid_ref_table_size(),
     alias_bif_test(node()),
     {ok, Node} = start_node(Config),
     alias_bif_test(Node),
     stop_node(Node),
+    check_pid_ref_table_size(PRTSz),
     ok.
 
 alias_bif_test(Node) ->
@@ -4081,10 +4102,12 @@ alias_bif_test(Node) ->
 
 
 monitor_alias(Config) when is_list(Config) ->
+    PRTSz = pid_ref_table_size(),
     monitor_alias_test(node()),
     {ok, Node} = start_node(Config),
     monitor_alias_test(Node),
     stop_node(Node),
+    check_pid_ref_table_size(PRTSz),
     ok.
 
 monitor_alias_test(Node) ->
@@ -4168,6 +4191,7 @@ monitor_alias_test(Node) ->
 spawn_monitor_alias(Config) when is_list(Config) ->
     %% Exit signals with immediate exit reasons are sent
     %% in a different manner than compound exit reasons.
+    PRTSz = pid_ref_table_size(),
     spawn_monitor_alias_test(node(), spawn_opt, normal),
     spawn_monitor_alias_test(node(), spawn_opt, make_ref()),
     spawn_monitor_alias_test(node(), spawn_request, normal),
@@ -4180,6 +4204,7 @@ spawn_monitor_alias(Config) when is_list(Config) ->
     spawn_monitor_alias_test(Node3, spawn_request, normal),
     {ok, Node4} = start_node(Config),
     spawn_monitor_alias_test(Node4, spawn_request, make_ref()),
+    check_pid_ref_table_size(PRTSz),
     ok.
 
 spawn_monitor_alias_test(Node, SpawnType, ExitReason) ->
@@ -4320,6 +4345,28 @@ spawn_monitor_alias_test(Node, SpawnType, ExitReason) ->
             ok
     end.
 
+alias_process_exit(Config) when is_list(Config) ->
+    Tester = self(),
+    CreatedAliases = make_ref(),
+    PRTSz = pid_ref_table_size(),
+    P = spawn_link(fun () ->
+                           A0 = alias([explicit_unalias]),
+                           A1 = alias([reply]),
+                           A2 = monitor(process, Tester, [{alias, explicit_unalias}]),
+                           A3 = monitor(process, Tester, [{alias, demonitor}]),
+                           A4 = monitor(process, Tester, [{alias, reply_demonitor}]),
+                           Tester ! CreatedAliases,
+                           receive after infinity -> ok end,
+                           some_module:some_function([A0, A1, A2, A3, A4])
+                   end),
+    receive CreatedAliases -> ok end,
+    PRTSz = erts_debug:get_internal_state(pid_ref_table_size) - 5,
+    unlink(P),
+    exit(P, kill),
+    false = is_process_alive(P),
+    check_pid_ref_table_size(PRTSz),
+    ok.
+
 monitor_tag(Config) when is_list(Config) ->
     %% Exit signals with immediate exit reasons are sent
     %% in a different manner than compound exit reasons, and