Erlang based BIF timer implementation for scalability

1 files changed, 181 insertions, 10 deletions

diff --git a/erts/preloaded/src/erlang.erl b/erts/preloaded/src/erlang.erl
index 79eb60f362..83010b17d2 100644
--- a/erts/preloaded/src/erlang.erl
+++ b/erts/preloaded/src/erlang.erl
@@ -89,7 +89,7 @@
 -export([binary_to_list/3, binary_to_term/1, binary_to_term/2]).
 -export([bit_size/1, bitsize/1, bitstring_to_list/1]).
 -export([bump_reductions/1, byte_size/1, call_on_load_function/1]).
--export([cancel_timer/1, check_old_code/1, check_process_code/2,
+-export([cancel_timer/1, cancel_timer/2, check_old_code/1, check_process_code/2,
 	 check_process_code/3, crc32/1]).
 -export([crc32/2, crc32_combine/3, date/0, decode_packet/3]).
 -export([delete_element/2]).
@@ -128,7 +128,7 @@
 -export([time_offset/0, time_offset/1, timestamp/0]).
 -export([process_display/2]).
 -export([process_flag/3, process_info/1, processes/0, purge_module/1]).
--export([put/2, raise/3, read_timer/1, ref_to_list/1, register/2]).
+-export([put/2, raise/3, read_timer/1, read_timer/2, ref_to_list/1, register/2]).
 -export([registered/0, resume_process/1, round/1, self/0, send_after/3]).
 -export([seq_trace/2, seq_trace_print/1, seq_trace_print/2, setnode/2]).
 -export([setnode/3, size/1, spawn/3, spawn_link/3, split_binary/2]).
@@ -427,8 +427,77 @@ call_on_load_function(_P1) ->
 -spec erlang:cancel_timer(TimerRef) -> Time | false when
       TimerRef :: reference(),
       Time :: non_neg_integer().
-cancel_timer(_TimerRef) ->
-    erlang:nif_error(undefined).
+cancel_timer(TimerRef) ->
+    try
+	case erts_internal:access_bif_timer(TimerRef) of
+	    undefined ->
+		false;
+	    {BTR, TSrv} ->
+		Req = erlang:make_ref(),
+		TSrv ! {cancel_timeout, BTR, erlang:self(),
+			true, Req, TimerRef},
+		receive
+		    {cancel_timer, Req, Result} ->
+			Result
+		end
+	end
+    catch
+	_:_ -> erlang:error(badarg, [TimerRef])
+    end.
+
+%% cancel_timer/2
+-spec erlang:cancel_timer(TimerRef, Options) -> Time | false | ok when
+      TimerRef :: reference(),
+      Option :: {async, boolean()} | {info, boolean()},
+      Options :: [Option],
+      Time :: non_neg_integer().
+cancel_timer(TimerRef, Options) ->
+    try
+	{Async, Info} = get_cancel_timer_options(Options, false, true),
+	case erts_internal:access_bif_timer(TimerRef) of
+	    undefined ->
+		case {Async, Info} of
+		    {true, true} ->
+			erlang:self() ! {cancel_timer, TimerRef, false}, ok;
+		    {false, true} ->
+			false;
+		    _ ->
+			ok
+		end;
+	    {BTR, TSrv} ->
+		case Async of
+		    true ->
+			TSrv ! {cancel_timeout, BTR, erlang:self(),
+				Info, TimerRef, TimerRef},
+			ok;
+		    false ->
+			Req = erlang:make_ref(),
+			TSrv ! {cancel_timeout, BTR, erlang:self(),
+				true, Req, TimerRef},
+			receive
+			    {cancel_timer, Req, Result} ->
+				case Info of
+				    true -> Result;
+				    false -> ok
+				end
+			end
+		end
+	end
+    catch
+	_:_ -> erlang:error(badarg, [TimerRef, Options])
+    end.
+
+get_cancel_timer_options([], Async, Info) ->
+    {Async, Info};
+get_cancel_timer_options([{async, Bool} | Opts],
+			 _Async, Info) when Bool == true;
+					    Bool == false ->
+    get_cancel_timer_options(Opts, Bool, Info);
+get_cancel_timer_options([{info, Bool} | Opts],
+			 Async, _Info) when Bool == true;
+					    Bool == false ->
+    get_cancel_timer_options(Opts, Async, Bool).
+    
 
 %% check_old_code/1
 -spec check_old_code(Module) -> boolean() when
@@ -1462,8 +1531,53 @@ raise(_Class, _Reason, _Stacktrace) ->
 %% read_timer/1
 -spec erlang:read_timer(TimerRef) -> non_neg_integer() | false when
       TimerRef :: reference().
-read_timer(_TimerRef) ->
-    erlang:nif_error(undefined).
+
+read_timer(TimerRef) ->
+    read_timer(TimerRef, []).
+
+%% read_timer/2
+-spec erlang:read_timer(TimerRef, Options) -> non_neg_integer() | false | ok when
+      TimerRef :: reference(),
+      Option :: {async, boolean()},
+      Options :: [Option].
+
+read_timer(TimerRef, Options) ->
+    try
+	Async = get_read_timer_options(Options, false),
+	case erts_internal:access_bif_timer(TimerRef) of
+	    undefined ->
+		case Async of
+		    true ->
+			erlang:self() ! {read_timer, TimerRef, false},
+			ok;
+		    false ->
+			false
+		end;
+	    {BTR, TSrv} ->
+		case Async of
+		    true ->
+			TSrv ! {read_timeout, BTR, erlang:self(),
+				TimerRef, TimerRef},
+			ok;
+		    false ->
+			Req = erlang:make_ref(),
+			TSrv ! {read_timeout, BTR, erlang:self(),
+				Req, TimerRef},
+			receive
+			    {read_timer, Req, Result} ->
+				Result
+			end
+		end
+	end
+    catch
+	_:_ -> erlang:error(badarg, [TimerRef])
+    end.
+
+get_read_timer_options([], Async) ->
+    Async;
+get_read_timer_options([{async, Bool} | Opts],
+		       _Async) when Bool == true; Bool == false ->
+    get_read_timer_options(Opts, Bool).
 
 %% ref_to_list/1
 -spec erlang:ref_to_list(Ref) -> string() when
@@ -1509,8 +1623,36 @@ self() ->
       Dest :: pid() | atom(),
       Msg :: term(),
       TimerRef :: reference().
-send_after(_Time, _Dest, _Msg) ->
-    erlang:nif_error(undefined).
+
+send_after(0, Dest, Msg) ->
+    try
+	true = ((erlang:is_pid(Dest)
+		 andalso erlang:node(Dest) == erlang:node())
+		orelse (erlang:is_atom(Dest)
+			andalso Dest /= undefined)),
+	try Dest ! Msg catch _:_ -> ok end,
+	erlang:make_ref()
+    catch
+	_:_ ->
+	    erlang:error(badarg, [0, Dest, Msg])
+    end;
+send_after(Time, Dest, Msg) ->
+    Now = erlang:monotonic_time(),
+    try
+	true = ((erlang:is_pid(Dest)
+		 andalso erlang:node(Dest) == erlang:node())
+		orelse (erlang:is_atom(Dest)
+			andalso Dest /= undefined)),
+	true = Time > 0,
+	true = Time < (1 bsl 32), % Maybe lift this restriction...
+	TO = Now + (erts_internal:time_unit()*Time) div 1000,
+	{BTR, TSrv, TRef} = erts_internal:create_bif_timer(),
+	TSrv ! {set_timeout, BTR, Dest, TO, TRef, Msg},
+	TRef
+    catch
+	_:_ ->
+	    erlang:error(badarg, [Time, Dest, Msg])
+    end.
 
 %% seq_trace/2
 -spec erlang:seq_trace(P1, P2) -> seq_trace_info_returns() | {term(), term(), term(), term(), term()} when
@@ -1583,8 +1725,37 @@ split_binary(_Bin, _Pos) ->
       Dest :: pid() | atom(),
       Msg :: term(),
       TimerRef :: reference().
-start_timer(_Time, _Dest, _Msg) ->
-    erlang:nif_error(undefined).
+start_timer(0, Dest, Msg) ->
+    try
+	true = ((erlang:is_pid(Dest)
+		 andalso erlang:node(Dest) == erlang:node())
+		orelse (erlang:is_atom(Dest)
+			andalso Dest /= undefined)),
+	TimerRef = erlang:make_ref(),
+	try Dest ! {timeout, TimerRef, Msg} catch _:_ -> ok end,
+	TimerRef
+    catch
+	_:_ ->
+	    erlang:error(badarg, [0, Dest, Msg])
+    end;
+start_timer(Time, Dest, Msg) ->
+    Now = erlang:monotonic_time(),
+    try
+	true = ((erlang:is_pid(Dest)
+		 andalso erlang:node(Dest) == erlang:node())
+		orelse (erlang:is_atom(Dest)
+			andalso Dest /= undefined)),
+	true = Time > 0,
+	true = Time < (1 bsl 32), % Maybe lift this restriction...
+	TO = Now + (erts_internal:time_unit()*Time) div 1000,
+	{BTR, TSrv, TimerRef} = erts_internal:create_bif_timer(),
+	TSrv ! {set_timeout, BTR, Dest, TO, TimerRef,
+		{timeout, TimerRef, Msg}},
+	TimerRef
+    catch
+	_:_ ->
+	    erlang:error(badarg, [Time, Dest, Msg])
+    end.
 
 %% suspend_process/2
 -spec erlang:suspend_process(Suspendee, OptList) -> boolean() when