erts: Implement tracer modules

Add the possibility to use modules as trace data receivers. The functions
in the module have to be nifs as otherwise complex trace probes will be
very hard to handle (complex means trace probes for ports for example).

This commit changes the way that the ptab->tracer field works from always
being an immediate, to now be NIL if no tracer is present or else be
the tuple {TracerModule, TracerState} where TracerModule is an atom that
is later used to lookup the appropriate tracer callbacks to call and
TracerState is just passed to the tracer callback. The default process and
port tracers have been rewritten to use the new API.

This commit also changes the order which trace messages are delivered to the
potential tracer process. Any enif_send done in a tracer module may be delayed
indefinitely because of lock order issues. If a message is delayed any other
trace message send from that process is also delayed so that order is preserved
for each traced entity. This means that for some trace events (i.e. send/receive)
the events may come in an unintuitive order (receive before send) to the
trace receiver. Timestamps are taken when the trace message is generated so
trace messages from differented processes may arrive with the timestamp
out of order.

Both the erlang:trace and seq_trace:set_system_tracer accept the new tracer
module tracers and also the backwards compatible arguments.

OTP-10267

7 files changed, 1030 insertions, 70 deletions

diff --git a/erts/emulator/test/Makefile b/erts/emulator/test/Makefile
index 2221b5830c..92182e3890 100644
--- a/erts/emulator/test/Makefile
+++ b/erts/emulator/test/Makefile
@@ -110,6 +110,8 @@ MODULES= \
 	trace_meta_SUITE \
 	trace_call_count_SUITE \
 	trace_call_time_SUITE \
+	tracer_SUITE \
+	tracer_test \
 	scheduler_SUITE \
 	old_scheduler_SUITE \
 	unique_SUITE \
diff --git a/erts/emulator/test/match_spec_SUITE.erl b/erts/emulator/test/match_spec_SUITE.erl
index 6b8d14b487..ea973276db 100644
--- a/erts/emulator/test/match_spec_SUITE.erl
+++ b/erts/emulator/test/match_spec_SUITE.erl
@@ -23,7 +23,7 @@
 -export([all/0, suite/0, not_run/1]).
 -export([test_1/1, test_2/1, test_3/1, bad_match_spec_bin/1,
 	 trace_control_word/1, silent/1, silent_no_ms/1, silent_test/1,
-	 ms_trace2/1, ms_trace3/1, boxed_and_small/1,
+	 ms_trace2/1, ms_trace3/1, ms_trace_dead/1, boxed_and_small/1,
 	 destructive_in_test_bif/1, guard_exceptions/1,
 	 empty_list/1,
 	 unary_plus/1, unary_minus/1, moving_labels/1]).
@@ -49,7 +49,7 @@ all() ->
 	false ->
 	    [test_1, test_2, test_3, bad_match_spec_bin,
 	     trace_control_word, silent, silent_no_ms, silent_test, ms_trace2,
-	     ms_trace3, boxed_and_small, destructive_in_test_bif,
+	     ms_trace3, ms_trace_dead, boxed_and_small, destructive_in_test_bif,
 	     guard_exceptions, unary_plus, unary_minus, fpe,
 	     moving_labels,
 	     faulty_seq_trace,
@@ -500,6 +500,8 @@ ms_trace2(Config) when is_list(Config) ->
                  [[call,return_to],[]]},
                 ms_trace2}]
       end),
+    %% Silence valgrind
+    erlang:trace_pattern({?MODULE,fn,'_'},[],[]),
     ok.
 
 
@@ -595,7 +597,35 @@ ms_trace3(Config) when is_list(Config) ->
       end),
     ok.
 
-
+ms_trace_dead(doc) ->
+    ["Test that a dead tracer is removed using ms"];
+ms_trace_dead(suite) -> [];
+ms_trace_dead(Config) when is_list(Config) ->
+    Self = self(),
+    TFun = fun F() -> receive M -> Self ! M, F() end end,
+    {Tracer, MRef} = spawn_monitor(TFun),
+    MetaTracer = spawn_link(TFun),
+    erlang:trace_pattern({?MODULE, f1, '_'},
+                         [{'_',[],[{trace,[],
+                                    [call,{const,{tracer,Tracer}}]}]}],
+                         [{meta, MetaTracer}]),
+    erlang:trace_pattern({?MODULE, f2, '_'}, []),
+    ?MODULE:f2(1,2),
+    ?MODULE:f1(1),
+    {tracer,Tracer} = erlang:trace_info(self(), tracer),
+    {flags,[call]} = erlang:trace_info(self(), flags),
+    ?MODULE:f2(2,3),
+    receive {trace, Self, call, {?MODULE, f2, _}} -> ok end,
+    exit(Tracer, stop),
+    receive {'DOWN',MRef,_,_,_} -> ok end,
+    ?MODULE:f1(2),
+    {tracer,[]} = erlang:trace_info(self(), tracer),
+    ?MODULE:f2(3,4),
+    TRef = erlang:trace_delivered(all),
+    receive {trace_delivered, _, TRef} -> ok end,
+    receive {trace_ts, Self, call, {?MODULE, f1, _}, _} -> ok end,
+    receive {trace_ts, Self, call, {?MODULE, f1, _}, _} -> ok end,
+    receive M -> ct:fail({unexpected, M}) after 10 -> ok end.
 
 %% Test that destructive operations in test bif does not really happen
 destructive_in_test_bif(Config) when is_list(Config) ->
@@ -905,34 +935,40 @@ collect([]) ->
 collect([TM | TMs]) ->
     io:format(        "Expecting:      ~p~n", [TM]),
     receive
-        M0 ->
-            M = case element(1, M0) of
-                    trace_ts ->
-                        list_to_tuple(lists:reverse(
-                                        tl(lists:reverse(tuple_to_list(M0)))));
-                    _ -> M0
-                end,
-            case is_function(TM,1) of
-                true ->
-                    case (catch TM(M)) of
-                        true ->
-                            io:format("Got:            ~p~n", [M]),
-                            collect(TMs);
-                        _ ->
-                            io:format("Got unexpected: ~p~n", [M]),
-                            flush({got_unexpected,M})
-                    end;
-
-                false ->
-                    case M of
-                        TM ->
-                            io:format("Got:            ~p~n", [M]),
-                            collect(TMs);
-                        _ ->
-                            io:format("Got unexpected: ~p~n", [M]),
-                            flush({got_unexpected,M})
-                    end
-            end
+        %% We only look at trace messages with the same tracee
+        %% as the message we are looking for. This because
+        %% the order of trace messages is only guaranteed from
+        %% within a single process.
+	M0 when element(2, M0) =:= element(2, TM); is_function(TM, 1) ->
+	    M = case element(1, M0) of
+		    trace_ts ->
+			list_to_tuple(lists:reverse(
+					tl(lists:reverse(tuple_to_list(M0)))));
+		    _ -> M0
+		end,
+	    case is_function(TM,1) of
+		true ->
+		    case (catch TM(M)) of
+			true ->
+			    io:format("Got:            ~p~n", [M]),
+			    collect(TMs);
+			_ ->
+			    io:format("Got unexpected: ~p~n", [M]),
+			    flush({got_unexpected,M})
+		    end;
+
+		false ->
+		    case M of
+			TM ->
+			    io:format("Got:            ~p~n", [M]),
+			    collect(TMs);
+			_ ->
+			    io:format("Got unexpected: ~p~n", [M]),
+			    flush({got_unexpected,M})
+		    end
+	    end
+    after 15000 ->
+            flush(timeout)
     end.
 
 flush(Reason) ->
diff --git a/erts/emulator/test/trace_SUITE.erl b/erts/emulator/test/trace_SUITE.erl
index 7aece926e3..d9974bd6f7 100644
--- a/erts/emulator/test/trace_SUITE.erl
+++ b/erts/emulator/test/trace_SUITE.erl
@@ -24,8 +24,8 @@
 %%% Tests the trace BIF.
 %%%
 
--export([all/0, suite/0,
-	 receive_trace/1, self_send/1,
+-export([all/0, suite/0, link_receive_call_correlation/0,
+         receive_trace/1, link_receive_call_correlation/1, self_send/1,
 	 timeout_trace/1, send_trace/1,
 	 procs_trace/1, dist_procs_trace/1,
 	 suspend/1, mutual_suspend/1, suspend_exit/1, suspender_exit/1,
@@ -48,7 +48,8 @@ suite() ->
      {timetrap, {seconds, 5}}].
 
 all() -> 
-    [cpu_timestamp, receive_trace, self_send, timeout_trace,
+    [cpu_timestamp, receive_trace, link_receive_call_correlation,
+     self_send, timeout_trace,
      send_trace, procs_trace, dist_procs_trace, suspend,
      mutual_suspend, suspend_exit, suspender_exit,
      suspend_system_limit, suspend_opts, suspend_waiting,
@@ -87,10 +88,10 @@ receive_trace(Config) when is_list(Config) ->
     1 = erlang:trace(Receiver, true, ['receive']),
     Hello = {hello, world},
     Receiver ! Hello,
-    {trace, Receiver, 'receive', Hello} = receive_first(),
+    {trace, Receiver, 'receive', Hello} = receive_first_trace(),
     Hello2 = {hello, again, world},
     Receiver ! Hello2,
-    {trace, Receiver, 'receive', Hello2} = receive_first(),
+    {trace, Receiver, 'receive', Hello2} = receive_first_trace(),
     receive_nothing(),
 
     %% Another process should not be able to trace Receiver.
@@ -104,6 +105,112 @@ receive_trace(Config) when is_list(Config) ->
     receive_nothing(),
     ok.
 
+%% Tests that receive of a message always happens before a call with
+%% that message and that links/unlinks are ordered together with the
+%% 'receive'.
+link_receive_call_correlation() ->
+    [{timetrap, {minutes, 5}}].
+link_receive_call_correlation(Config) when is_list(Config) ->
+    Receiver = fun_spawn(fun F() ->
+                                 receive
+                                     stop -> ok;
+                                     M -> receive_msg(M), F()
+                                 end
+                         end),
+    process_flag(trap_exit, true),
+
+    %% Trace the process; make sure that we receive the trace messages.
+    1 = erlang:trace(Receiver, true, ['receive', procs, call, timestamp, scheduler_id]),
+    1 = erlang:trace_pattern({?MODULE, receive_msg, '_'}, [], [local]),
+
+    Num = 100000,
+
+    (fun F(0) -> [];
+         F(N) ->
+             if N rem 2 == 0 ->
+                     link(Receiver);
+                true ->
+                     unlink(Receiver)
+             end,
+             [Receiver ! N | F(N-1)]
+     end)(Num),
+
+    Receiver ! stop,
+    MonRef = erlang:monitor(process, Receiver),
+    receive {'DOWN', MonRef, _, _, _} -> ok end,
+    Ref = erlang:trace_delivered(Receiver),
+    receive {trace_delivered, _, Ref} -> ok end,
+
+    Msgs = (fun F() -> receive M -> [M | F()] after 1 -> [] end end)(),
+
+    case check_consistent(Receiver, Num, Num, Num, Msgs) of
+        ok ->
+            ok;
+        {error, Reason} ->
+            ct:log("~p", [Msgs]),
+            ct:fail({error, Reason})
+    end.
+
+-define(schedid, , _).
+
+check_consistent(_Pid, Recv, Call, _LU, [Msg | _]) when Recv > Call ->
+    {error, Msg};
+check_consistent(Pid, Recv, Call, LU, [Msg | Msgs]) ->
+
+    case Msg of
+        {trace, Pid, 'receive', Recv ?schedid} ->
+            check_consistent(Pid,Recv - 1, Call, LU, Msgs);
+        {trace_ts, Pid, 'receive', Recv ?schedid, _} ->
+            check_consistent(Pid,Recv - 1, Call, LU, Msgs);
+
+        {trace, Pid, call, {?MODULE, receive_msg, [Call]} ?schedid} ->
+            check_consistent(Pid,Recv, Call - 1, LU, Msgs);
+        {trace_ts, Pid, call, {?MODULE, receive_msg, [Call]} ?schedid, _} ->
+            check_consistent(Pid,Recv, Call - 1, LU, Msgs);
+
+        %% We check that for each receive we have gotten a
+        %% getting_linked or getting_unlinked message. Also
+        %% if we receive a getting_linked, then the next
+        %% message we expect to receive is an even number
+        %% and odd number for getting_unlinked.
+        {trace, Pid, getting_linked, _Self ?schedid}
+          when Recv rem 2 == 0, Recv == LU ->
+            check_consistent(Pid, Recv, Call, LU - 1, Msgs);
+        {trace_ts, Pid, getting_linked, _Self ?schedid, _}
+          when Recv rem 2 == 0, Recv == LU ->
+            check_consistent(Pid, Recv, Call, LU - 1, Msgs);
+
+        {trace, Pid, getting_unlinked, _Self ?schedid}
+          when Recv rem 2 == 1, Recv == LU ->
+            check_consistent(Pid, Recv, Call, LU - 1, Msgs);
+        {trace_ts, Pid, getting_unlinked, _Self ?schedid, _}
+          when Recv rem 2 == 1, Recv == LU ->
+            check_consistent(Pid, Recv, Call, LU - 1, Msgs);
+
+        {trace,Pid,'receive',Ignore ?schedid}
+          when Ignore == stop; Ignore == timeout ->
+            check_consistent(Pid, Recv, Call, LU, Msgs);
+        {trace_ts,Pid,'receive',Ignore ?schedid,_}
+          when Ignore == stop; Ignore == timeout ->
+            check_consistent(Pid, Recv, Call, LU, Msgs);
+
+        {trace, Pid, exit, normal ?schedid} ->
+            check_consistent(Pid, Recv, Call, LU, Msgs);
+        {trace_ts, Pid, exit, normal  ?schedid, _} ->
+            check_consistent(Pid, Recv, Call, LU, Msgs);
+        {'EXIT', Pid, normal} ->
+            check_consistent(Pid, Recv, Call, LU, Msgs);
+        Msg ->
+            {error, Msg}
+    end;
+check_consistent(_, 0, 0, 0, []) ->
+    ok;
+check_consistent(_, Recv, Call, LU, []) ->
+    {error,{Recv, Call, LU}}.
+
+receive_msg(M) ->
+    M.
+
 %% Test that traces are generated for messages sent
 %% and received to/from self().
 self_send(Config) when is_list(Config) ->
@@ -134,8 +241,8 @@ timeout_trace(Config) when is_list(Config) ->
     Process = fun_spawn(fun process/0),
     1 = erlang:trace(Process, true, ['receive']),
     Process ! timeout_please,
-    {trace, Process, 'receive', timeout_please} = receive_first(),
-    {trace, Process, 'receive', timeout} = receive_first(),
+    {trace, Process, 'receive', timeout_please} = receive_first_trace(),
+    {trace, Process, 'receive', timeout} = receive_first_trace(),
     receive_nothing(),
     ok.
 
@@ -149,13 +256,13 @@ send_trace(Config) when is_list(Config) ->
     %% Check that a message sent to another process is traced.
     1 = erlang:trace(Sender, true, [send]),
     Sender ! {send_please, Receiver, to_receiver},
-    {trace, Sender, send, to_receiver, Receiver} = receive_first(),
+    {trace, Sender, send, to_receiver, Receiver} = receive_first_trace(),
     receive_nothing(),
 
     %% Check that a message sent to another registered process is traced.
     register(?MODULE,Receiver),
     Sender ! {send_please, ?MODULE, to_receiver},
-    {trace, Sender, send, to_receiver, ?MODULE} = receive_first(),
+    {trace, Sender, send, to_receiver, ?MODULE} = receive_first_trace(),
     receive_nothing(),
     unregister(?MODULE),
 
@@ -163,14 +270,14 @@ send_trace(Config) when is_list(Config) ->
     Sender ! {send_please, self(), to_myself},
     receive to_myself -> ok end,
     Self = self(),
-    {trace, Sender, send, to_myself, Self} = receive_first(),
+    {trace, Sender, send, to_myself, Self} = receive_first_trace(),
     receive_nothing(),
 
     %% Check that a message sent to dead process is traced.
     {Pid,Ref} = spawn_monitor(fun() -> ok end),
     receive {'DOWN',Ref,_,_,_} -> ok end,
     Sender ! {send_please, Pid, to_dead},
-    {trace, Sender, send_to_non_existing_process, to_dead, Pid} = receive_first(),
+    {trace, Sender, send_to_non_existing_process, to_dead, Pid} = receive_first_trace(),
     receive_nothing(),
 
     %% Check that a message sent to unknown registrated process is traced.
@@ -178,7 +285,7 @@ send_trace(Config) when is_list(Config) ->
     1 = erlang:trace(BadargSender, true, [send]),
     unlink(BadargSender),
     BadargSender ! {send_please, not_registered, to_unknown},
-    {trace, BadargSender, send, to_unknown, not_registered} = receive_first(),
+    {trace, BadargSender, send, to_unknown, not_registered} = receive_first_trace(),
     receive_nothing(),
 
     %% Another process should not be able to trace Sender.
@@ -211,9 +318,9 @@ procs_trace(Config) when is_list(Config) ->
     %% spawn, link
     Proc1 ! {spawn_link_please, Self, MFA},
     Proc3 = receive {spawned, Proc1, P3} -> P3 end,
-    {trace, Proc1, spawn, Proc3, MFA} = receive_first(),
+    {trace, Proc1, spawn, Proc3, MFA} = receive_first_trace(),
     io:format("Proc3 = ~p ~n", [Proc3]),
-    {trace, Proc1, link, Proc3} = receive_first(),
+    {trace, Proc1, link, Proc3} = receive_first_trace(),
     receive_nothing(),
     %%
     %% getting_unlinked by exit()
@@ -221,60 +328,60 @@ procs_trace(Config) when is_list(Config) ->
     Reason3 = make_ref(),
     Proc1 ! {send_please, Proc3, {exit_please, Reason3}},
     receive {Proc1, {'EXIT', Proc3, Reason3}} -> ok end,
-    {trace, Proc1, getting_unlinked, Proc3} = receive_first(),
+    {trace, Proc1, getting_unlinked, Proc3} = receive_first_trace(),
     Proc1 ! {trap_exit_please, false},
     receive_nothing(),
     %%
     %% link
     Proc1 ! {link_please, Proc2},
-    {trace, Proc1, link, Proc2} = receive_first(),
+    {trace, Proc1, link, Proc2} = receive_first_trace(),
     receive_nothing(),
     %%
     %% unlink
     Proc1 ! {unlink_please, Proc2},
-    {trace, Proc1, unlink, Proc2} = receive_first(),
+    {trace, Proc1, unlink, Proc2} = receive_first_trace(),
     receive_nothing(),
     %%
     %% getting_linked
     Proc2 ! {link_please, Proc1},
-    {trace, Proc1, getting_linked, Proc2} = receive_first(),
+    {trace, Proc1, getting_linked, Proc2} = receive_first_trace(),
     receive_nothing(),
     %%
     %% getting_unlinked
     Proc2 ! {unlink_please, Proc1},
-    {trace, Proc1, getting_unlinked, Proc2} = receive_first(),
+    {trace, Proc1, getting_unlinked, Proc2} = receive_first_trace(),
     receive_nothing(),
     %%
     %% register
     true = register(Name, Proc1),
-    {trace, Proc1, register, Name} = receive_first(),
+    {trace, Proc1, register, Name} = receive_first_trace(),
     receive_nothing(),
     %%
     %% unregister
     true = unregister(Name),
-    {trace, Proc1, unregister, Name} = receive_first(),
+    {trace, Proc1, unregister, Name} = receive_first_trace(),
     receive_nothing(),
     %%
     %% exit (with registered name, due to link)
     Reason4 = make_ref(),
     Proc1 ! {spawn_link_please, Self, MFA},
     Proc4 = receive {spawned, Proc1, P4} -> P4 end,
-    {trace, Proc1, spawn, Proc4, MFA} = receive_first(),
+    {trace, Proc1, spawn, Proc4, MFA} = receive_first_trace(),
     io:format("Proc4 = ~p ~n", [Proc4]),
-    {trace, Proc1, link, Proc4} = receive_first(),
+    {trace, Proc1, link, Proc4} = receive_first_trace(),
     Proc1 ! {register_please, Name, Proc1},
-    {trace, Proc1, register, Name} = receive_first(),
+    {trace, Proc1, register, Name} = receive_first_trace(),
     Proc4 ! {exit_please, Reason4},
     receive {'EXIT', Proc1, Reason4} -> ok end,
-    {trace, Proc1, exit, Reason4} = receive_first(),
-    {trace, Proc1, unregister, Name} = receive_first(),
+    {trace, Proc1, exit, Reason4} = receive_first_trace(),
+    {trace, Proc1, unregister, Name} = receive_first_trace(),
     receive_nothing(),
     %%
     %% exit (not linked to tracing process)
     1 = erlang:trace(Proc2, true, [procs]),
     Reason2 = make_ref(),
     Proc2 ! {exit_please, Reason2},
-    {trace, Proc2, exit, Reason2} = receive_first(),
+    {trace, Proc2, exit, Reason2} = receive_first_trace(),
     receive_nothing(),
     ok.
 
@@ -299,45 +406,45 @@ dist_procs_trace(Config) when is_list(Config) ->
     Proc1 ! {trap_exit_please, true},
     Proc3 = receive {spawned, Proc1, P3} -> P3 end,
     io:format("Proc3 = ~p ~n", [Proc3]),
-    {trace, Proc1, getting_linked, Proc3} = receive_first(),
+    {trace, Proc1, getting_linked, Proc3} = receive_first_trace(),
     Reason3 = make_ref(),
     Proc1 ! {send_please, Proc3, {exit_please, Reason3}},
     receive {Proc1, {'EXIT', Proc3, Reason3}} -> ok end,
-    {trace, Proc1, getting_unlinked, Proc3} = receive_first(),
+    {trace, Proc1, getting_unlinked, Proc3} = receive_first_trace(),
     Proc1 ! {trap_exit_please, false},
     receive_nothing(),
     %%
     %% link
     Proc1 ! {link_please, Proc2},
-    {trace, Proc1, link, Proc2} = receive_first(),
+    {trace, Proc1, link, Proc2} = receive_first_trace(),
     receive_nothing(),
     %%
     %% unlink
     Proc1 ! {unlink_please, Proc2},
-    {trace, Proc1, unlink, Proc2} = receive_first(),
+    {trace, Proc1, unlink, Proc2} = receive_first_trace(),
     receive_nothing(),
     %%
     %% getting_linked
     Proc2 ! {link_please, Proc1},
-    {trace, Proc1, getting_linked, Proc2} = receive_first(),
+    {trace, Proc1, getting_linked, Proc2} = receive_first_trace(),
     receive_nothing(),
     %%
     %% getting_unlinked
     Proc2 ! {unlink_please, Proc1},
-    {trace, Proc1, getting_unlinked, Proc2} = receive_first(),
+    {trace, Proc1, getting_unlinked, Proc2} = receive_first_trace(),
     receive_nothing(),
     %%
     %% exit (with registered name, due to link)
     Name = list_to_atom(OtherName),
     Reason2 = make_ref(),
     Proc1 ! {link_please, Proc2},
-    {trace, Proc1, link, Proc2} = receive_first(),
+    {trace, Proc1, link, Proc2} = receive_first_trace(),
     Proc1 ! {register_please, Name, Proc1},
-    {trace, Proc1, register, Name} = receive_first(),
+    {trace, Proc1, register, Name} = receive_first_trace(),
     Proc2 ! {exit_please, Reason2},
     receive {'EXIT', Proc1, Reason2} -> ok end,
-    {trace, Proc1, exit, Reason2} = receive_first(),
-    {trace, Proc1, unregister, Name} = receive_first(),
+    {trace, Proc1, exit, Reason2} = receive_first_trace(),
+    {trace, Proc1, unregister, Name} = receive_first_trace(),
     receive_nothing(),
     %%
     %% Done.
@@ -1247,7 +1354,8 @@ existing_clear(Config) when is_list(Config) ->
               [N, M]),
     {flags, []} = erlang:trace_info(Self, flags),
     {tracer, []} = erlang:trace_info(Self, tracer),
-    M = N + 1, % Since trace could not be enabled on the tracer.
+    M = N, % Used to be N + 1, but from 19.0 the tracer is also traced
+
     ok.
 
 %% Test that an invalid flag cause badarg
@@ -1317,6 +1425,13 @@ receive_first() ->
         Any -> Any
     end.
 
+%% Waits for and returns the first message in the message queue.
+
+receive_first_trace() ->
+    receive
+	Any when element(1,Any) =:= trace; element(1,Any) =:= trace_ts -> Any
+    end.
+
 %% Ensures that there is no message in the message queue.
 
 receive_nothing() ->
@@ -1421,7 +1536,7 @@ fun_spawn(Fun, Args) ->
 start_node(Name) ->
     Pa = filename:dirname(code:which(?MODULE)),
     Cookie = atom_to_list(erlang:get_cookie()),
-    test_server:start_node(Name, slave, 
+    test_server:start_node(Name, slave,
                            [{args, "-setcookie " ++ Cookie ++" -pa " ++ Pa}]).
 
 stop_node(Node) ->
diff --git a/erts/emulator/test/tracer_SUITE.erl b/erts/emulator/test/tracer_SUITE.erl
new file mode 100644
index 0000000000..c62512e6ba
--- /dev/null
+++ b/erts/emulator/test/tracer_SUITE.erl
@@ -0,0 +1,622 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+-module(tracer_SUITE).
+
+%%%
+%%% Tests the tracer module interface
+%%%
+
+-export([all/0, suite/0,groups/0, init_per_suite/1, end_per_suite/1,
+	 init_per_group/2,end_per_group/2, init_per_testcase/2,
+         end_per_testcase/2]).
+-export([load/1, unload/1, reload/1, invalid_tracers/1]).
+-export([send/1, recv/1, spawn/1, exit/1, link/1, unlink/1,
+         getting_linked/1, getting_unlinked/1, register/1, unregister/1,
+         in/1, out/1, gc_start/1, gc_end/1]).
+
+suite() -> [{ct_hooks,[ts_install_cth]},
+            {timetrap, {minutes, 1}}].
+
+all() ->
+    [load, unload, reload, invalid_tracers, {group, basic}].
+
+groups() ->
+    [{ basic, [], [send, recv, spawn, exit, link, unlink, getting_linked,
+                   getting_unlinked, register, unregister, in, out,
+                   gc_start, gc_end]}].
+
+init_per_suite(Config) ->
+    purge(),
+    Config.
+
+end_per_suite(_Config) ->
+    ok.
+
+init_per_group(_GroupName, Config) ->
+    Config.
+
+end_per_group(_GroupName, Config) ->
+    Config.
+
+init_per_testcase(TC, Config) when TC =:= load; TC =:= reload ->
+
+    DataDir = proplists:get_value(data_dir, Config),
+
+    Pid = erlang:spawn(fun F() ->
+                               receive
+                                   {get, Pid} ->
+                                       Pid ! DataDir,
+                                       F()
+                               end
+                       end),
+    register(tracer_test_config, Pid),
+    Config;
+init_per_testcase(_, Config) ->
+    DataDir = proplists:get_value(data_dir, Config),
+    case catch tracer_test:enabled(trace_status, self(), self()) of
+        discard ->
+            ok;
+        _ ->
+            tracer_test:load(DataDir)
+    end,
+    Config.
+
+end_per_testcase(TC, _Config) when TC =:= load; TC =:= reload ->
+    purge(),
+    exit(whereis(tracer_test_config), kill),
+    ok;
+end_per_testcase(_, _Config) ->
+    purge(),
+    ok.
+
+load(_Config) ->
+    purge(),
+    1 = erlang:trace(self(), true, [{tracer, tracer_test, []}, call]),
+    purge(),
+    1 = erlang:trace_pattern({?MODULE, all, 0}, [],
+                             [{meta, tracer_test, []}]),
+    ok.
+
+unload(_Config) ->
+
+    ServerFun = fun F(0, undefined) ->
+                        receive
+                            {N, Pid} -> F(N, Pid)
+                        end;
+                    F(0, Pid) ->
+                        Pid ! done,
+                        F(0, undefined);
+                    F(N, Pid) ->
+                        ?MODULE:all(),
+                        F(N-1, Pid)
+                end,
+
+    Pid = erlang:spawn_link(fun() -> ServerFun(0, undefined) end),
+
+
+    Tc = fun(N) ->
+                 Pid ! {N, self()},
+                 receive done -> ok after 1000 -> ct:fail(timeout) end,
+                 trace_delivered(Pid)
+         end,
+
+    1 = erlang:trace(Pid, true, [{tracer, tracer_test,
+                                  {#{ call => trace}, self(), []}},
+                                 call]),
+    1 = erlang:trace_pattern({?MODULE, all, 0}, [], []),
+
+    Tc(1),
+    receive _ -> ok after 0 -> ct:fail(timeout) end,
+
+    code:purge(tracer_test),
+    code:delete(tracer_test),
+
+    Tc(1),
+    receive M1 -> ct:fail({unexpected_message, M1}) after 0 -> ok end,
+
+    code:purge(tracer_test),
+
+    Tc(1),
+    receive M2 -> ct:fail({unexpected_message, M2}) after 0 -> ok end,
+
+    ok.
+
+%% This testcase is here to make sure there are not
+%% segfaults when reloading the current nifs.
+reload(_Config) ->
+
+    Tracer = spawn_link(fun F() -> receive _M -> F() end end),
+    Tracee = spawn_link(fun F() -> ?MODULE:all(), F() end),
+
+
+    [begin
+         Ref = make_ref(),
+         State = {#{ call => trace }, Tracer, [Ref]},
+         erlang:trace(Tracee, true, [{tracer, tracer_test,State}, call]),
+         erlang:trace_pattern({?MODULE, all, 0}, []),
+
+         false = code:purge(tracer_test),
+         {module, _} = code:load_file(tracer_test),
+
+         %% There is a race involved in between when the internal nif cache
+         %% is purged and when the reload_loop needs the tracer module
+         %% so the tracer may be removed or still there.
+         case erlang:trace_info(Tracee, tracer) of
+             {tracer, []} -> ok;
+             {tracer, {tracer_test, State}} -> ok
+         end,
+
+         false = code:purge(tracer_test),
+         true = code:delete(tracer_test),
+         false = code:purge(tracer_test)
+     end || _ <- lists:seq(1,15)],
+
+    ok.
+
+invalid_tracers(_Config) ->
+    FailTrace = fun(A) ->
+                        try erlang:trace(self(), true, A) of
+                            _ -> ct:fail(A)
+                        catch _:_ -> ok end
+                end,
+
+    FailTrace([{tracer, foobar}, call]),
+    FailTrace([{tracer, foobar, []}, call]),
+    FailTrace([{tracer, make_ref(), []}, call]),
+    FailTrace([{tracer, lists, []}, call]),
+
+    FailTP = fun(MS,FL) ->
+                     try erlang:trace_pattern({?MODULE,all,0}, MS, FL) of
+                            _ -> ct:fail({MS, FL})
+                        catch _:_ -> ok end
+                end,
+
+    FailTP([],[{meta, foobar}]),
+    FailTP([],[{meta, foobar, []}]),
+    FailTP([],[{meta, make_ref(), []}]),
+    FailTP([],[{meta, lists, []}]),
+
+    ok.
+
+
+
+send(_Config) ->
+
+    Self = self(),
+    Tc = fun(Pid) ->
+                 Pid ! fun() -> Self ! ok end,
+                 receive ok -> ok after 100 -> ct:fail(timeout) end
+         end,
+
+    Expect = fun(Pid, State, EOpts) ->
+                     receive
+                         Msg ->
+                             {Pid, send, State, Pid, ok, Self, Opts} = Msg,
+                             check_opts(EOpts, Opts)
+                     end
+             end,
+    test(send, Tc, Expect).
+
+
+recv(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! ok
+         end,
+
+    Expect = fun(Pid, State, EOpts) ->
+                     receive
+                         Msg ->
+                             {undefined, 'receive', State, Pid, ok, undefined, Opts} = Msg,
+                             check_opts(EOpts, Opts)
+                     end
+             end,
+
+    test('receive', Tc, Expect, false).
+
+spawn(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! fun() -> erlang:spawn(lists,seq,[1,10]), ok end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {Pid, spawn, State, Pid, NewPid,
+                         {lists,seq,[1,10]}, Opts} = Msg,
+                        check_opts(EOpts, Opts),
+                        true = is_pid(NewPid) andalso NewPid /= Pid
+                end
+             end,
+
+    test(spawn, procs, Tc, Expect, true).
+
+exit(_Config) ->
+    Tc = fun(Pid) ->
+                 Pid ! fun() -> exit end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {Pid, exit, State, Pid, normal, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts)
+                end
+             end,
+
+    test(exit, procs, Tc, Expect, true, true).
+
+link(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! fun() ->
+                               SPid = erlang:spawn(fun() -> receive _ -> ok end end),
+                               erlang:link(SPid),
+                               ok
+                       end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {Pid, link, State, Pid, NewPid, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts),
+                        true = is_pid(NewPid) andalso NewPid /= Pid
+                end
+             end,
+
+    test(link, procs, Tc, Expect, true).
+
+unlink(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! fun() ->
+                               SPid = erlang:spawn(fun() -> receive _ -> ok end end),
+                               erlang:link(SPid),
+                               erlang:unlink(SPid),
+                               ok
+                       end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {Pid, unlink, State, Pid, NewPid, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts),
+                        true = is_pid(NewPid) andalso NewPid /= Pid
+                end
+             end,
+
+    test(unlink, procs, Tc, Expect, true).
+
+getting_linked(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! fun() ->
+                               Self = self(),
+                               erlang:spawn(fun() -> erlang:link(Self) end),
+                               ok
+                       end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {NewPid, getting_linked, State, Pid, NewPid, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts),
+                        true = is_pid(NewPid) andalso NewPid /= Pid
+                end
+             end,
+
+    test(getting_linked, procs, Tc, Expect, false).
+
+getting_unlinked(_Config) ->
+    Tc = fun(Pid) ->
+                 Pid ! fun() ->
+                               Self = self(),
+                               erlang:spawn(fun() ->
+                                                    erlang:link(Self),
+                                                    erlang:unlink(Self)
+                                            end),
+                               ok
+                       end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {NewPid, getting_unlinked, State, Pid, NewPid, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts),
+                        true = is_pid(NewPid) andalso NewPid /= Pid
+                end
+             end,
+
+    test(getting_unlinked, procs, Tc, Expect, false).
+
+register(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! fun() ->
+                               erlang:register(?MODULE, self()),
+                               erlang:unregister(?MODULE),
+                               ok
+                       end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {Pid, register, State, Pid, ?MODULE, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts)
+                end
+             end,
+
+    test(register, procs, Tc, Expect, true).
+
+unregister(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! fun() ->
+                               erlang:register(?MODULE, self()),
+                               erlang:unregister(?MODULE),
+                               ok
+                       end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {Pid, unregister, State, Pid, ?MODULE, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts)
+                end
+             end,
+
+    test(unregister, procs, Tc, Expect, true).
+
+in(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Self = self(),
+                 Pid ! fun() -> receive after 1 -> Self ! ok end end,
+                 receive ok -> ok end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                N = (fun F(N) ->
+                             receive
+                                 Msg ->
+                                     {Pid, in, State, Pid, _,
+                                      undefined, Opts} = Msg,
+                                     check_opts(EOpts, Opts),
+                                     F(N+1)
+                             after 0 -> N
+                             end
+                     end)(0),
+                true = N > 0
+             end,
+
+    test(in, running, Tc, Expect, true).
+
+out(_Config) ->
+    Tc = fun(Pid) ->
+                 Pid ! fun() -> receive after 10 -> exit end end,
+                 Ref = erlang:monitor(process, Pid),
+                 receive {'DOWN', Ref, _, _, _} -> ok end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                %% We cannot predict how many out schedules there will be
+                N = (fun F(N) ->
+                             receive
+                                 Msg ->
+                                     {Pid, out, State, Pid, _,
+                                      undefined, Opts} = Msg,
+                                     check_opts(EOpts, Opts),
+                                     F(N+1)
+                             after 0 -> N
+                             end
+                     end)(0),
+                true = N > 0
+             end,
+
+    test(out, running, Tc, Expect, true, true).
+
+gc_start(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! fun() ->
+                               erlang:garbage_collect(),
+                               ok
+                       end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {Pid, gc_start, State, Pid, _, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts)
+                end
+             end,
+
+    test(gc_start, garbage_collection, Tc, Expect, true).
+
+gc_end(_Config) ->
+
+    Tc = fun(Pid) ->
+                 Pid ! fun() ->
+                               erlang:garbage_collect(),
+                               ok
+                       end
+         end,
+
+    Expect =
+        fun(Pid, State, EOpts) ->
+                receive
+                    Msg ->
+                        {Pid, gc_end, State, Pid, _, undefined, Opts} = Msg,
+                        check_opts(EOpts, Opts)
+                end
+             end,
+
+    test(gc_end, garbage_collection, Tc, Expect, true).
+
+test(Event, Tc, Expect) ->
+    test(Event, Tc, Expect, true).
+test(Event, Tc, Expect, Removes) ->
+    test(Event, Event, Tc, Expect, Removes).
+test(Event, TraceFlag, Tc, Expect, Removes) ->
+    test(Event, TraceFlag, Tc, Expect, Removes, false).
+test(Event, TraceFlag, Tc, Expect, Removes, Dies) ->
+
+    ComplexState = {fun() -> ok end, <<0:(128*8)>>},
+    Opts = #{ timestamp => undefined,
+              scheduler_id => undefined,
+              match_spec_result => true },
+
+    %% Test that trace works
+    State1 = {#{ Event => trace }, self(), ComplexState},
+    Pid1 = start_tracee(),
+    1 = erlang:trace(Pid1, true, [TraceFlag, {tracer, tracer_test, State1}]),
+    Tc(Pid1),
+    ok = trace_delivered(Pid1),
+
+    Expect(Pid1, State1, Opts),
+    receive M11 -> ct:fail({unexpected, M11}) after 0 -> ok end,
+    if not Dies ->
+            {flags, [TraceFlag]} = erlang:trace_info(Pid1, flags),
+            {tracer, {tracer_test, State1}} = erlang:trace_info(Pid1, tracer),
+            erlang:trace(Pid1, false, [TraceFlag]);
+       true -> ok
+    end,
+
+    %% Test that trace works with scheduler id and timestamp
+    Pid1T = start_tracee(),
+    1 = erlang:trace(Pid1T, true, [TraceFlag, {tracer, tracer_test, State1},
+                                   timestamp, scheduler_id]),
+    Tc(Pid1T),
+    ok = trace_delivered(Pid1T),
+
+    Expect(Pid1T, State1, Opts#{ scheduler_id := number,
+                                 timestamp := timestamp}),
+    receive M11T -> ct:fail({unexpected, M11T}) after 0 -> ok end,
+    if not Dies ->
+            {flags, [scheduler_id, TraceFlag, timestamp]}
+                = erlang:trace_info(Pid1T, flags),
+            {tracer, {tracer_test, State1}} = erlang:trace_info(Pid1T, tracer),
+            erlang:trace(Pid1T, false, [TraceFlag]);
+       true -> ok
+    end,
+
+    %% Test that  discard works
+    Pid2 = start_tracee(),
+    State2 = {#{ Event => discard }, self(), ComplexState},
+    1 = erlang:trace(Pid2, true, [TraceFlag, {tracer, tracer_test, State2}]),
+    Tc(Pid2),
+    ok = trace_delivered(Pid2),
+    receive M2 -> ct:fail({unexpected, M2}) after 0 -> ok end,
+    if not Dies ->
+            {flags, [TraceFlag]} = erlang:trace_info(Pid2, flags),
+            {tracer, {tracer_test, State2}} = erlang:trace_info(Pid2, tracer),
+            erlang:trace(Pid2, false, [TraceFlag]);
+       true ->
+            ok
+    end,
+
+    %% Test that remove works
+    Pid3 = start_tracee(),
+    State3 = {#{ Event => remove }, self(), ComplexState},
+    1 = erlang:trace(Pid3, true, [TraceFlag, {tracer, tracer_test, State3}]),
+    Tc(Pid3),
+    ok = trace_delivered(Pid3),
+    receive M3 -> ct:fail({unexpected, M3}) after 0 -> ok end,
+    if not Dies ->
+            if Removes ->
+                    {flags, []} = erlang:trace_info(Pid3, flags),
+                    {tracer, []} = erlang:trace_info(Pid3, tracer);
+               true ->
+                    {flags, [TraceFlag]} = erlang:trace_info(Pid3, flags),
+                    {tracer, {tracer_test, State3}} = erlang:trace_info(Pid3, tracer)
+            end,
+            erlang:trace(Pid3, false, [TraceFlag]);
+       true ->
+            ok
+    end,
+    ok.
+
+check_opts(#{ scheduler_id := number } = E, #{ scheduler_id := N } = O)
+  when is_integer(N) ->
+    E1 = maps:remove(scheduler_id, E),
+    O1 = maps:remove(scheduler_id, O),
+    if E1 == O1 -> ok;
+       true -> ct:fail({invalid_opts, E, O})
+    end;
+check_opts(Opts, Opts) ->
+    ok;
+check_opts(E,O) ->
+    ct:fail({invalid_opts, E, O}).
+
+start_tracee() ->
+    spawn_link(
+      fun F() ->
+              receive
+                  Action when is_function(Action) ->
+                      case Action() of
+                          ok ->
+                              F();
+                          Err ->
+                              Err
+                      end;
+                  _ ->
+                      F()
+              end
+      end).
+
+trace_delivered(Pid) ->
+    Ref = erlang:trace_delivered(Pid),
+    receive
+        {trace_delivered, Pid, Ref} ->
+            ok
+    after 1000 ->
+            timeout
+    end.
+
+purge() ->
+    %% Make sure module is not loaded
+    case erlang:module_loaded(tracer_test) of
+        true ->
+            code:purge(tracer_test),
+            true = code:delete(tracer_test),
+            code:purge(tracer_test);
+        _ ->
+            ok
+    end.
diff --git a/erts/emulator/test/tracer_SUITE_data/Makefile.src b/erts/emulator/test/tracer_SUITE_data/Makefile.src
new file mode 100644
index 0000000000..154bd70ccc
--- /dev/null
+++ b/erts/emulator/test/tracer_SUITE_data/Makefile.src
@@ -0,0 +1,8 @@
+
+NIF_LIBS = tracer_test@dll@
+
+all: $(NIF_LIBS)
+
+@SHLIB_RULES@
+
+$(NIF_LIBS): tracer_test.c
diff --git a/erts/emulator/test/tracer_SUITE_data/tracer_test.c b/erts/emulator/test/tracer_SUITE_data/tracer_test.c
new file mode 100644
index 0000000000..8b4be1345d
--- /dev/null
+++ b/erts/emulator/test/tracer_SUITE_data/tracer_test.c
@@ -0,0 +1,122 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2009-2014. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#include "erl_nif.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <limits.h>
+
+/* NIF interface declarations */
+static int load(ErlNifEnv* env, void** priv_data, ERL_NIF_TERM load_info);
+static int upgrade(ErlNifEnv* env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info);
+static void unload(ErlNifEnv* env, void* priv_data);
+
+/* The NIFs: */
+static ERL_NIF_TERM enabled(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM trace(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[]);
+
+static ErlNifFunc nif_funcs[] = {
+    {"enabled", 3, enabled},
+    {"trace", 6, trace}
+};
+
+ERL_NIF_INIT(tracer_test, nif_funcs, load, NULL, upgrade, unload)
+
+static ERL_NIF_TERM atom_discard;
+static ERL_NIF_TERM atom_ok;
+
+#define ASSERT(expr) assert(expr)
+
+static int load(ErlNifEnv* env, void** priv_data, ERL_NIF_TERM load_info)
+{
+
+    atom_discard = enif_make_atom(env, "discard");
+    atom_ok = enif_make_atom(env, "ok");
+
+    *priv_data = NULL;
+
+    return 0;
+}
+
+static void unload(ErlNifEnv* env, void* priv_data)
+{
+
+}
+
+static int upgrade(ErlNifEnv* env, void** priv_data, void** old_priv_data,
+		   ERL_NIF_TERM load_info)
+{
+    if (*old_priv_data != NULL) {
+	return -1; /* Don't know how to do that */
+    }
+    if (*priv_data != NULL) {
+	return -1; /* Don't know how to do that */
+    }
+    if (load(env, priv_data, load_info)) {
+	return -1;
+    }
+    return 0;
+}
+
+static ERL_NIF_TERM enabled(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+    int state_arity;
+    const ERL_NIF_TERM *state_tuple;
+    ERL_NIF_TERM value;
+    ASSERT(argc == 3);
+
+    if (!enif_get_tuple(env, argv[1], &state_arity, &state_tuple))
+        return atom_discard;
+
+    if (enif_get_map_value(env, state_tuple[0], argv[0], &value)) {
+        return value;
+    } else {
+        return atom_discard;
+    }
+}
+
+static ERL_NIF_TERM trace(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
+{
+    int state_arity;
+    ErlNifPid self, to;
+    ERL_NIF_TERM *tuple, msg;
+    const ERL_NIF_TERM *state_tuple;
+    ASSERT(argc == 6);
+
+    enif_get_tuple(env, argv[1], &state_arity, &state_tuple);
+
+    tuple = enif_alloc(sizeof(ERL_NIF_TERM)*(argc+1));
+    memcpy(tuple+1,argv,sizeof(ERL_NIF_TERM)*argc);
+
+    if (enif_self(env, &self)) {
+        tuple[0] = enif_make_pid(env, &self);
+    } else {
+        tuple[0] = enif_make_atom(env, "undefined");
+    }
+
+    msg = enif_make_tuple_from_array(env, tuple, argc + 1);
+    enif_get_local_pid(env, state_tuple[1], &to);
+    enif_send(env, &to, NULL, msg);
+    enif_free(tuple);
+
+    return atom_ok;
+}
diff --git a/erts/emulator/test/tracer_test.erl b/erts/emulator/test/tracer_test.erl
new file mode 100644
index 0000000000..d4778f4531
--- /dev/null
+++ b/erts/emulator/test/tracer_test.erl
@@ -0,0 +1,55 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 1997-2013. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+
+-module(tracer_test).
+
+%%%
+%%% Test tracer
+%%%
+
+-export([enabled/3, trace/6]).
+-export([load/1, load/2]).
+-on_load(load/0).
+
+enabled(_, _, _) ->
+    erlang:nif_error(nif_not_loaded).
+
+trace(_, _, _, _, _, _) ->
+    erlang:nif_error(nif_not_loaded).
+
+load() ->
+    case whereis(tracer_test_config) of
+        undefined ->
+            ok;
+        Pid ->
+            Pid ! {get, self()},
+            receive
+                {Conf, Postfix} ->
+                    load(Conf, Postfix);
+                Conf ->
+                    load(Conf)
+            end
+    end.
+
+load(DataDir) ->
+    load(DataDir, "").
+load(DataDir, Postfix) ->
+    SoFile = atom_to_list(?MODULE) ++ Postfix,
+    erlang:load_nif(filename:join(DataDir, SoFile) , 0).