diff options
| -rw-r--r-- | lib/stdlib/src/gen_statem.erl | 230 |
1 files changed, 83 insertions, 147 deletions
diff --git a/lib/stdlib/src/gen_statem.erl b/lib/stdlib/src/gen_statem.erl index faa43fbc1e..8965af253b 100644 --- a/lib/stdlib/src/gen_statem.erl +++ b/lib/stdlib/src/gen_statem.erl @@ -1,7 +1,7 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 2016-2018. All Rights Reserved. +%% Copyright Ericsson AB 2016-2019. 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. @@ -398,17 +398,11 @@ timeout_event_type(Type) -> data :: term(), postponed = [] :: [{event_type(),term()}], %% - timer_refs = #{} :: % timer ref => the timer's event type - #{reference() => timeout_event_type()}, - timer_types = #{} :: % timer's event type => timer ref - #{timeout_event_type() => reference()}, - cancel_timers = 0 :: non_neg_integer(), - %% We add a timer to both timer_refs and timer_types - %% when we start it. When we request an asynchronous - %% timer cancel we remove it from timer_types. When - %% the timer cancel message arrives we remove it from - %% timer_refs. - %% + timers = {#{},#{}} :: + {%% timer ref => the timer's event type + TimerRefs :: #{reference() => timeout_event_type()}, + %% timer's event type => timer ref + TimerTypes :: #{timeout_event_type() => reference()}}, hibernate = false :: boolean(), hibernate_after = infinity :: timeout()}). @@ -857,7 +851,7 @@ wakeup_from_hibernate(Parent, Debug, S) -> %% and detours through sys:handle_system_message/7 and proc_lib:hibernate/3 %% Entry point for system_continue/3 -loop(Parent, Debug, #state{hibernate = true, cancel_timers = 0} = S) -> +loop(Parent, Debug, #state{hibernate = true} = S) -> loop_hibernate(Parent, Debug, S); loop(Parent, Debug, S) -> loop_receive(Parent, Debug, S). @@ -893,70 +887,20 @@ loop_receive( Q = [EXIT], terminate(exit, Reason, ?STACKTRACE(), Debug, S, Q); {timeout,TimerRef,TimerMsg} -> - #state{ - timer_refs = TimerRefs, - timer_types = TimerTypes} = S, - case TimerRefs of - #{TimerRef := TimerType} -> - %% We know of this timer; is it a running - %% timer or a timer being cancelled that - %% managed to send a late timeout message? - case TimerTypes of - #{TimerType := TimerRef} -> - %% The timer type maps back to this - %% timer ref, so it was a running timer - %% Unregister the triggered timeout - NewTimerRefs = - maps:remove(TimerRef, TimerRefs), - NewTimerTypes = - maps:remove(TimerType, TimerTypes), - loop_receive_result( - Parent, Debug, - S#state{ - timer_refs = NewTimerRefs, - timer_types = NewTimerTypes}, - TimerType, TimerMsg); - _ -> - %% This was a late timeout message - %% from timer being cancelled, so - %% ignore it and expect a cancel_timer - %% msg shortly - loop_receive(Parent, Debug, S) - end; - _ -> + case S#state.timers of + {#{TimerRef := TimerType} = TimerRefs,TimerTypes} -> + %% Our timer + NewTimers = + {maps:remove(TimerRef, TimerRefs), + maps:remove(TimerType, TimerTypes)}, + loop_receive_result( + Parent, Debug, + S#state{timers = NewTimers}, + TimerType, TimerMsg); + {#{},_} -> %% Not our timer; present it as an event loop_receive_result(Parent, Debug, S, info, Msg) end; - {cancel_timer,TimerRef,_} -> - #state{ - timer_refs = TimerRefs, - cancel_timers = CancelTimers, - hibernate = Hibernate} = S, - case TimerRefs of - #{TimerRef := _} -> - %% We must have requested a cancel - %% of this timer so it is already - %% removed from TimerTypes - NewTimerRefs = - maps:remove(TimerRef, TimerRefs), - NewCancelTimers = CancelTimers - 1, - NewS = - S#state{ - timer_refs = NewTimerRefs, - cancel_timers = NewCancelTimers}, - if - Hibernate =:= true, NewCancelTimers =:= 0 -> - %% No more cancel_timer msgs to expect; - %% we can hibernate - loop_hibernate(Parent, Debug, NewS); - NewCancelTimers >= 0 -> % Assert - loop_receive(Parent, Debug, NewS) - end; - _ -> - %% Not our cancel_timer msg; - %% present it as an event - loop_receive_result(Parent, Debug, S, info, Msg) - end; _ -> %% External msg case Msg of @@ -1429,9 +1373,7 @@ loop_event_done( loop_event_done( Parent, Debug_0, #state{ - state = State, postponed = P_0, - timer_refs = TimerRefs_0, timer_types = TimerTypes_0, - cancel_timers = CancelTimers_0} = S, + state = State, postponed = P_0, timers = Timers_0} = S, Events_0, Event_0, NextState, NewData, #trans_opts{ hibernate = Hibernate, timeouts_r = TimeoutsR, @@ -1463,22 +1405,17 @@ loop_event_done( if NextState =:= State -> {Events_0,P_1, - cancel_timer_by_type( - timeout, {TimerTypes_0,CancelTimers_0})}; + cancel_timer_by_type(timeout, Timers_0)}; true -> {lists:reverse(P_1, Events_0), [], cancel_timer_by_type( state_timeout, - cancel_timer_by_type( - timeout, {TimerTypes_0,CancelTimers_0}))} - %% The state timer is removed from TimerTypes - %% but remains in TimerRefs until we get - %% the cancel_timer msg + cancel_timer_by_type(timeout, Timers_0))} end, - {TimerRefs_3,{TimerTypes_3,CancelTimers_3},TimeoutEvents} = + {Timers_3,TimeoutEvents} = %% Stop and start timers - parse_timers(TimerRefs_0, Timers_2, TimeoutsR), + parse_timers(Timers_2, TimeoutsR), %% Place next events last in reversed queue Events_3R = lists:reverse(Events_2, NextEventsR), %% Enqueue immediate timeout events @@ -1489,9 +1426,7 @@ loop_event_done( state = NextState, data = NewData, postponed = P_2, - timer_refs = TimerRefs_3, - timer_types = TimerTypes_3, - cancel_timers = CancelTimers_3, + timers = Timers_3, hibernate = Hibernate}, lists:reverse(Events_4R)). @@ -1501,8 +1436,7 @@ loop_event_done_fast( Parent, Hibernate, #state{ state = NextState, - timer_types = #{timeout := _} = TimerTypes, - cancel_timers = CancelTimers} = S, + timers = {_,#{timeout := _}} = Timers} = S, Events, P, NextState, NewData) -> %% %% Same state, event timeout active @@ -1510,8 +1444,7 @@ loop_event_done_fast( loop_event_done_fast( Parent, Hibernate, S, Events, P, NextState, NewData, - cancel_timer_by_type( - timeout, {TimerTypes,CancelTimers})); + cancel_timer_by_type(timeout, Timers)); loop_event_done_fast( Parent, Hibernate, #state{state = NextState} = S, @@ -1529,8 +1462,7 @@ loop_event_done_fast( loop_event_done_fast( Parent, Hibernate, #state{ - timer_types = #{timeout := _} = TimerTypes, - cancel_timers = CancelTimers} = S, + timers = {_,#{timeout := _}} = Timers} = S, Events, P, NextState, NewData) -> %% %% State change, event timeout active @@ -1540,13 +1472,11 @@ loop_event_done_fast( lists:reverse(P, Events), [], NextState, NewData, cancel_timer_by_type( state_timeout, - cancel_timer_by_type( - timeout, {TimerTypes,CancelTimers}))); + cancel_timer_by_type(timeout, Timers))); loop_event_done_fast( Parent, Hibernate, #state{ - timer_types = #{state_timeout := _} = TimerTypes, - cancel_timers = CancelTimers} = S, + timers = {_,#{state_timeout := _}} = Timers} = S, Events, P, NextState, NewData) -> %% %% State change, state timeout active @@ -1556,8 +1486,7 @@ loop_event_done_fast( lists:reverse(P, Events), [], NextState, NewData, cancel_timer_by_type( state_timeout, - cancel_timer_by_type( - timeout, {TimerTypes,CancelTimers}))); + cancel_timer_by_type(timeout, Timers))); loop_event_done_fast( Parent, Hibernate, #state{} = S, @@ -1577,9 +1506,7 @@ loop_event_done_fast( %% Fast path %% loop_event_done_fast( - Parent, Hibernate, S, - Events, P, NextState, NewData, - {TimerTypes,CancelTimers}) -> + Parent, Hibernate, S, Events, P, NextState, NewData, Timers) -> %% loop_event_done( Parent, ?not_sys_debug, @@ -1587,8 +1514,7 @@ loop_event_done_fast( state = NextState, data = NewData, postponed = P, - timer_types = TimerTypes, - cancel_timers = CancelTimers, + timers = Timers, hibernate = Hibernate}, Events). @@ -1703,41 +1629,40 @@ classify_time(_, _, Opts) when is_list(Opts) -> %% and pending event timer %% %% Stop and start timers non-event timers -parse_timers(TimerRefs, Timers, TimeoutsR) -> - parse_timers(TimerRefs, Timers, TimeoutsR, #{}, []). +parse_timers(Timers, TimeoutsR) -> + parse_timers(Timers, TimeoutsR, #{}, []). %% -parse_timers( - TimerRefs, Timers, [], _Seen, TimeoutEvents) -> +parse_timers(Timers, [], _Seen, TimeoutEvents) -> %% - {TimerRefs,Timers,TimeoutEvents}; + {Timers,TimeoutEvents}; parse_timers( - TimerRefs, Timers, [Timeout|TimeoutsR], Seen, TimeoutEvents) -> + Timers, [Timeout|TimeoutsR], Seen, TimeoutEvents) -> %% case Timeout of {TimerType,Time,TimerMsg,TimerOpts} -> %% Absolute timer parse_timers( - TimerRefs, Timers, TimeoutsR, Seen, TimeoutEvents, + Timers, TimeoutsR, Seen, TimeoutEvents, TimerType, Time, TimerMsg, listify(TimerOpts)); %% Relative timers below {TimerType,0,TimerMsg} -> parse_timers( - TimerRefs, Timers, TimeoutsR, Seen, TimeoutEvents, + Timers, TimeoutsR, Seen, TimeoutEvents, TimerType, zero, TimerMsg, []); {TimerType,Time,TimerMsg} -> parse_timers( - TimerRefs, Timers, TimeoutsR, Seen, TimeoutEvents, + Timers, TimeoutsR, Seen, TimeoutEvents, TimerType, Time, TimerMsg, []) end. parse_timers( - TimerRefs, Timers, TimeoutsR, Seen, TimeoutEvents, + Timers, TimeoutsR, Seen, TimeoutEvents, TimerType, Time, TimerMsg, TimerOpts) -> case Seen of #{TimerType := _} -> %% Type seen before - ignore parse_timers( - TimerRefs, Timers, TimeoutsR, Seen, TimeoutEvents); + Timers, TimeoutsR, Seen, TimeoutEvents); #{} -> %% Unseen type - handle NewSeen = Seen#{TimerType => true}, @@ -1745,13 +1670,13 @@ parse_timers( infinity -> %% Cancel any running timer parse_timers( - TimerRefs, cancel_timer_by_type(TimerType, Timers), + cancel_timer_by_type(TimerType, Timers), TimeoutsR, NewSeen, TimeoutEvents); zero -> %% Cancel any running timer %% Handle zero time timeouts later parse_timers( - TimerRefs, cancel_timer_by_type(TimerType, Timers), + cancel_timer_by_type(TimerType, Timers), TimeoutsR, NewSeen, [{TimerType,TimerMsg}|TimeoutEvents]); _ -> @@ -1759,26 +1684,27 @@ parse_timers( TimerRef = erlang:start_timer( Time, self(), TimerMsg, TimerOpts), - case Timers of - {#{TimerType := OldTimerRef} = TimerTypes, - CancelTimers} -> - %% Cancel the running timer + {TimerRefs,TimerTypes} = Timers, + case TimerTypes of + #{TimerType := OldTimerRef} -> + %% Cancel the running timer, + %% update the timeout type, + %% insert the new timer ref, + %% and remove the old timer ref cancel_timer(OldTimerRef), - NewCancelTimers = CancelTimers + 1, %% Insert the new timer into %% both TimerRefs and TimerTypes parse_timers( - TimerRefs#{TimerRef => TimerType}, - {TimerTypes#{TimerType => TimerRef}, - NewCancelTimers}, + {maps:remove( + OldTimerRef, + TimerRefs#{TimerRef => TimerType}), + TimerTypes#{TimerType := TimerRef}}, TimeoutsR, NewSeen, TimeoutEvents); - {#{} = TimerTypes,CancelTimers} -> - %% Insert the new timer into - %% both TimerRefs and TimerTypes + #{} -> + %% Insert the new timer type and ref parse_timers( - TimerRefs#{TimerRef => TimerType}, - {TimerTypes#{TimerType => TimerRef}, - CancelTimers}, + {TimerRefs#{TimerRef => TimerType}, + TimerTypes#{TimerType => TimerRef}}, TimeoutsR, NewSeen, TimeoutEvents) end end @@ -2021,24 +1947,34 @@ listify(Item) when is_list(Item) -> listify(Item) -> [Item]. + +-define(cancel_timer(TimerRef), + case erlang:cancel_timer(TimerRef) of + false -> + %% No timer found and we have not seen the timeout message + receive + {timeout,(TimerRef),_} -> + ok + end; + _ -> + %% Timer was running + ok + end). + +-compile({inline, [cancel_timer/1]}). +cancel_timer(TimerRef) -> + ?cancel_timer(TimerRef). + %% Cancel timer if running, otherwise no op %% -%% This is an asynchronous cancel so the timer is not really cancelled -%% until we get a cancel_timer msg i.e {cancel_timer,TimerRef,_}. -%% In the mean time we might get a timeout message. -%% -%% Remove the timer from TimerTypes. -%% When we get the cancel_timer msg we remove it from TimerRefs. +%% Remove the timer from Timers. -compile({inline, [cancel_timer_by_type/2]}). -cancel_timer_by_type(TimerType, {TimerTypes,CancelTimers} = TT_CT) -> +cancel_timer_by_type(TimerType, {TimerRefs,TimerTypes} = Timers) -> case TimerTypes of #{TimerType := TimerRef} -> - ok = erlang:cancel_timer(TimerRef, [{async,true}]), - {maps:remove(TimerType, TimerTypes),CancelTimers + 1}; + ?cancel_timer(TimerRef), + {maps:remove(TimerRef, TimerRefs), + maps:remove(TimerType, TimerTypes)}; #{} -> - TT_CT + Timers end. - --compile({inline, [cancel_timer/1]}). -cancel_timer(TimerRef) -> - ok = erlang:cancel_timer(TimerRef, [{async,true}]). |