diff options
| -rw-r--r-- | erts/preloaded/ebin/erts_code_purger.beam | bin | 1132 -> 9020 bytes | |||
| -rw-r--r-- | erts/preloaded/src/erts_code_purger.erl | 283 | ||||
| -rw-r--r-- | lib/kernel/src/code_server.erl | 250 | ||||
| -rw-r--r-- | lib/kernel/test/code_SUITE.erl | 1 |
4 files changed, 290 insertions, 244 deletions
diff --git a/erts/preloaded/ebin/erts_code_purger.beam b/erts/preloaded/ebin/erts_code_purger.beam Binary files differindex 176497b052..adfe298a44 100644 --- a/erts/preloaded/ebin/erts_code_purger.beam +++ b/erts/preloaded/ebin/erts_code_purger.beam diff --git a/erts/preloaded/src/erts_code_purger.erl b/erts/preloaded/src/erts_code_purger.erl index 1ef4d096b7..6bb6e4fcdc 100644 --- a/erts/preloaded/src/erts_code_purger.erl +++ b/erts/preloaded/src/erts_code_purger.erl @@ -22,11 +22,288 @@ %% Purpose : Implement system process erts_code_purger %% to handle code module purging. --export([start/0]). +-export([start/0, purge/1, soft_purge/1]). -spec start() -> term(). start() -> - receive M -> + register(erts_code_purger, self()), + process_flag(trap_exit, true), + loop(). + +loop() -> + receive + {purge,Mod,From,Ref} when is_atom(Mod), is_pid(From) -> + Res = do_purge(Mod), + From ! {reply, purge, Res, Ref}; + + {soft_purge,Mod,From,Ref} when is_atom(Mod), is_pid(From) -> + Res = do_soft_purge(Mod), + From ! {reply, soft_purge, Res, Ref}; + + M -> erlang:display({"erts_code_purger got msg", M}) end, - start(). + loop(). + + +%% purge(Module) +%% Kill all processes running code from *old* Module, and then purge the +%% module. Return {WasOld, DidKill}: +%% {false, false} there was no old module to purge +%% {true, false} module purged, no process killed +%% {true, true} module purged, at least one process killed + +purge(Mod) when is_atom(Mod) -> + Ref = make_ref(), + erts_code_purger ! {purge, Mod, self(), Ref}, + receive + {reply, purge, Result, Ref} -> + Result + end. + + +do_purge(Mod) -> + case erlang:check_old_code(Mod) of + false -> + {false, false}; + true -> + true = erlang:copy_literals(Mod, true), + DidKill = check_proc_code(erlang:processes(), Mod, true), + true = erlang:copy_literals(Mod, false), + try + erlang:purge_module(Mod) + catch + _:_ -> ignore + end, + {true, DidKill} + end. + +%% soft_purge(Module) +%% Purge old code only if no procs remain that run old code. +%% Return true in that case, false if procs remain (in this +%% case old code is not purged) + +soft_purge(Mod) -> + Ref = make_ref(), + erts_code_purger ! {soft_purge, Mod, self(), Ref}, + receive + {reply, soft_purge, Result, Ref} -> + Result + end. + + +do_soft_purge(Mod) -> + case erlang:check_old_code(Mod) of + false -> + true; + true -> + true = erlang:copy_literals(Mod, true), + case check_proc_code(erlang:processes(), Mod, false) of + false -> + true = erlang:copy_literals(Mod, false), + false; + true -> + true = erlang:copy_literals(Mod, false), + try + erlang:purge_module(Mod) + catch + _:_ -> ignore + end, + true + end + end. + +%% +%% check_proc_code(Pids, Mod, Hard) - Send asynchronous +%% requests to all processes to perform a check_process_code +%% operation. Each process will check their own state and +%% reply with the result. If 'Hard' equals +%% - true, processes that refer 'Mod' will be killed. If +%% any processes were killed true is returned; otherwise, +%% false. +%% - false, and any processes refer 'Mod', false will +%% returned; otherwise, true. +%% +%% Requests will be sent to all processes identified by +%% Pids at once, but without allowing GC to be performed. +%% Check process code operations that are aborted due to +%% GC need, will be restarted allowing GC. However, only +%% ?MAX_CPC_GC_PROCS outstanding operation allowing GC at +%% a time will be allowed. This in order not to blow up +%% memory wise. +%% +%% We also only allow ?MAX_CPC_NO_OUTSTANDING_KILLS +%% outstanding kills. This both in order to avoid flooding +%% our message queue with 'DOWN' messages and limiting the +%% amount of memory used to keep references to all +%% outstanding kills. +%% + +%% We maybe should allow more than two outstanding +%% GC requests, but for now we play it safe... +-define(MAX_CPC_GC_PROCS, 2). +-define(MAX_CPC_NO_OUTSTANDING_KILLS, 10). + +-record(cpc_static, {hard, module, tag}). + +-record(cpc_kill, {outstanding = [], + no_outstanding = 0, + waiting = [], + killed = false}). + +check_proc_code(Pids, Mod, Hard) -> + Tag = erlang:make_ref(), + CpcS = #cpc_static{hard = Hard, + module = Mod, + tag = Tag}, + check_proc_code(CpcS, cpc_init(CpcS, Pids, 0), 0, [], #cpc_kill{}, true). + +check_proc_code(#cpc_static{hard = true}, 0, 0, [], + #cpc_kill{outstanding = [], waiting = [], killed = Killed}, + true) -> + %% No outstanding requests. We did a hard check, so result is whether or + %% not we killed any processes... + Killed; +check_proc_code(#cpc_static{hard = false}, 0, 0, [], _KillState, Success) -> + %% No outstanding requests and we did a soft check... + Success; +check_proc_code(#cpc_static{hard = false, tag = Tag} = CpcS, NoReq0, NoGcReq0, + [], _KillState, false) -> + %% Failed soft check; just cleanup the remaining replies corresponding + %% to the requests we've sent... + {NoReq1, NoGcReq1} = receive + {check_process_code, {Tag, _P, GC}, _Res} -> + case GC of + false -> {NoReq0-1, NoGcReq0}; + true -> {NoReq0, NoGcReq0-1} + end + end, + check_proc_code(CpcS, NoReq1, NoGcReq1, [], _KillState, false); +check_proc_code(#cpc_static{tag = Tag} = CpcS, NoReq0, NoGcReq0, NeedGC0, + KillState0, Success) -> + + %% Check if we should request a GC operation + {NoGcReq1, NeedGC1} = case NoGcReq0 < ?MAX_CPC_GC_PROCS of + GcOpAllowed when GcOpAllowed == false; + NeedGC0 == [] -> + {NoGcReq0, NeedGC0}; + _ -> + {NoGcReq0+1, cpc_request_gc(CpcS,NeedGC0)} + end, + + %% Wait for a cpc reply or 'DOWN' message + {NoReq1, NoGcReq2, Pid, Result, KillState1} = cpc_recv(Tag, + NoReq0, + NoGcReq1, + KillState0), + + %% Check the result of the reply + case Result of + aborted -> + %% Operation aborted due to the need to GC in order to + %% determine if the process is referring the module. + %% Schedule the operation for restart allowing GC... + check_proc_code(CpcS, NoReq1, NoGcReq2, [Pid|NeedGC1], KillState1, + Success); + false -> + %% Process not referring the module; done with this process... + check_proc_code(CpcS, NoReq1, NoGcReq2, NeedGC1, KillState1, + Success); + true -> + %% Process referring the module... + case CpcS#cpc_static.hard of + false -> + %% ... and soft check. The whole operation failed so + %% no point continuing; clean up and fail... + check_proc_code(CpcS, NoReq1, NoGcReq2, [], KillState1, + false); + true -> + %% ... and hard check; schedule kill of it... + check_proc_code(CpcS, NoReq1, NoGcReq2, NeedGC1, + cpc_sched_kill(Pid, KillState1), Success) + end; + 'DOWN' -> + %% Handled 'DOWN' message + check_proc_code(CpcS, NoReq1, NoGcReq2, NeedGC1, + KillState1, Success) + end. + +cpc_recv(Tag, NoReq, NoGcReq, #cpc_kill{outstanding = []} = KillState) -> + receive + {check_process_code, {Tag, Pid, GC}, Res} -> + cpc_handle_cpc(NoReq, NoGcReq, GC, Pid, Res, KillState) + end; +cpc_recv(Tag, NoReq, NoGcReq, + #cpc_kill{outstanding = [R0, R1, R2, R3, R4 | _]} = KillState) -> + receive + {'DOWN', R, process, _, _} when R == R0; + R == R1; + R == R2; + R == R3; + R == R4 -> + cpc_handle_down(NoReq, NoGcReq, R, KillState); + {check_process_code, {Tag, Pid, GC}, Res} -> + cpc_handle_cpc(NoReq, NoGcReq, GC, Pid, Res, KillState) + end; +cpc_recv(Tag, NoReq, NoGcReq, #cpc_kill{outstanding = [R|_]} = KillState) -> + receive + {'DOWN', R, process, _, _} -> + cpc_handle_down(NoReq, NoGcReq, R, KillState); + {check_process_code, {Tag, Pid, GC}, Res} -> + cpc_handle_cpc(NoReq, NoGcReq, GC, Pid, Res, KillState) + end. + +cpc_handle_down(NoReq, NoGcReq, R, #cpc_kill{outstanding = Rs, + no_outstanding = N} = KillState) -> + {NoReq, NoGcReq, undefined, 'DOWN', + cpc_sched_kill_waiting(KillState#cpc_kill{outstanding = cpc_list_rm(R, Rs), + no_outstanding = N-1})}. + +cpc_list_rm(R, [R|Rs]) -> + Rs; +cpc_list_rm(R0, [R1|Rs]) -> + [R1|cpc_list_rm(R0, Rs)]. + +cpc_handle_cpc(NoReq, NoGcReq, false, Pid, Res, KillState) -> + {NoReq-1, NoGcReq, Pid, Res, KillState}; +cpc_handle_cpc(NoReq, NoGcReq, true, Pid, Res, KillState) -> + {NoReq, NoGcReq-1, Pid, Res, KillState}. + +cpc_sched_kill_waiting(#cpc_kill{waiting = []} = KillState) -> + KillState; +cpc_sched_kill_waiting(#cpc_kill{outstanding = Rs, + no_outstanding = N, + waiting = [P|Ps]} = KillState) -> + R = erlang:monitor(process, P), + exit(P, kill), + KillState#cpc_kill{outstanding = [R|Rs], + no_outstanding = N+1, + waiting = Ps, + killed = true}. + +cpc_sched_kill(Pid, #cpc_kill{no_outstanding = N, waiting = Pids} = KillState) + when N >= ?MAX_CPC_NO_OUTSTANDING_KILLS -> + KillState#cpc_kill{waiting = [Pid|Pids]}; +cpc_sched_kill(Pid, + #cpc_kill{outstanding = Rs, no_outstanding = N} = KillState) -> + R = erlang:monitor(process, Pid), + exit(Pid, kill), + KillState#cpc_kill{outstanding = [R|Rs], + no_outstanding = N+1, + killed = true}. + +cpc_request(#cpc_static{tag = Tag, module = Mod}, Pid, AllowGc) -> + erlang:check_process_code(Pid, Mod, [{async, {Tag, Pid, AllowGc}}, + {allow_gc, AllowGc}]). + +cpc_request_gc(CpcS, [Pid|Pids]) -> + cpc_request(CpcS, Pid, true), + Pids. + +cpc_init(_CpcS, [], NoReqs) -> + NoReqs; +cpc_init(CpcS, [Pid|Pids], NoReqs) -> + cpc_request(CpcS, Pid, false), + cpc_init(CpcS, Pids, NoReqs+1). + +% end of check_proc_code() implementation. diff --git a/lib/kernel/src/code_server.erl b/lib/kernel/src/code_server.erl index 4361bb7b60..1a42cc0e9f 100644 --- a/lib/kernel/src/code_server.erl +++ b/lib/kernel/src/code_server.erl @@ -1281,254 +1281,22 @@ absname_vr([[X, $:]|Name], _, _AbsBase) -> absname(filename:join(Name), Dcwd). -%% do_purge(Module) -%% Kill all processes running code from *old* Module, and then purge the -%% module. Return true if any processes killed, else false. -do_purge(Mod0) -> - Mod = to_atom(Mod0), - case erlang:check_old_code(Mod) of - false -> - false; - true -> - true = erlang:copy_literals(Mod, true), - Res = check_proc_code(erlang:processes(), Mod, true), - true = erlang:copy_literals(Mod, false), - try - erlang:purge_module(Mod) - catch - _:_ -> ignore - end, - Res +is_loaded(M, Db) -> + case ets:lookup(Db, M) of + [{M,File}] -> {file,File}; + [] -> false end. -%% do_soft_purge(Module) -%% Purge old code only if no procs remain that run old code. -%% Return true in that case, false if procs remain (in this -%% case old code is not purged) +do_purge(Mod0) -> + Mod = to_atom(Mod0), + {_WasOld, DidKill} = erts_code_purger:purge(Mod), + DidKill. do_soft_purge(Mod0) -> Mod = to_atom(Mod0), - case erlang:check_old_code(Mod) of - false -> - true; - true -> - true = erlang:copy_literals(Mod, true), - case check_proc_code(erlang:processes(), Mod, false) of - false -> - true = erlang:copy_literals(Mod, false), - false; - true -> - true = erlang:copy_literals(Mod, false), - try - erlang:purge_module(Mod) - catch - _:_ -> ignore - end, - true - end - end. - -%% -%% check_proc_code(Pids, Mod, Hard) - Send asynchronous -%% requests to all processes to perform a check_process_code -%% operation. Each process will check their own state and -%% reply with the result. If 'Hard' equals -%% - true, processes that refer 'Mod' will be killed. If -%% any processes were killed true is returned; otherwise, -%% false. -%% - false, and any processes refer 'Mod', false will -%% returned; otherwise, true. -%% -%% Requests will be sent to all processes identified by -%% Pids at once, but without allowing GC to be performed. -%% Check process code operations that are aborted due to -%% GC need, will be restarted allowing GC. However, only -%% ?MAX_CPC_GC_PROCS outstanding operation allowing GC at -%% a time will be allowed. This in order not to blow up -%% memory wise. -%% -%% We also only allow ?MAX_CPC_NO_OUTSTANDING_KILLS -%% outstanding kills. This both in order to avoid flooding -%% our message queue with 'DOWN' messages and limiting the -%% amount of memory used to keep references to all -%% outstanding kills. -%% - -%% We maybe should allow more than two outstanding -%% GC requests, but for now we play it safe... --define(MAX_CPC_GC_PROCS, 2). --define(MAX_CPC_NO_OUTSTANDING_KILLS, 10). - --record(cpc_static, {hard, module, tag}). - --record(cpc_kill, {outstanding = [], - no_outstanding = 0, - waiting = [], - killed = false}). - -check_proc_code(Pids, Mod, Hard) -> - Tag = erlang:make_ref(), - CpcS = #cpc_static{hard = Hard, - module = Mod, - tag = Tag}, - check_proc_code(CpcS, cpc_init(CpcS, Pids, 0), 0, [], #cpc_kill{}, true). - -check_proc_code(#cpc_static{hard = true}, 0, 0, [], - #cpc_kill{outstanding = [], waiting = [], killed = Killed}, - true) -> - %% No outstanding requests. We did a hard check, so result is whether or - %% not we killed any processes... - Killed; -check_proc_code(#cpc_static{hard = false}, 0, 0, [], _KillState, Success) -> - %% No outstanding requests and we did a soft check... - Success; -check_proc_code(#cpc_static{hard = false, tag = Tag} = CpcS, NoReq0, NoGcReq0, - [], _KillState, false) -> - %% Failed soft check; just cleanup the remaining replies corresponding - %% to the requests we've sent... - {NoReq1, NoGcReq1} = receive - {check_process_code, {Tag, _P, GC}, _Res} -> - case GC of - false -> {NoReq0-1, NoGcReq0}; - true -> {NoReq0, NoGcReq0-1} - end - end, - check_proc_code(CpcS, NoReq1, NoGcReq1, [], _KillState, false); -check_proc_code(#cpc_static{tag = Tag} = CpcS, NoReq0, NoGcReq0, NeedGC0, - KillState0, Success) -> - - %% Check if we should request a GC operation - {NoGcReq1, NeedGC1} = case NoGcReq0 < ?MAX_CPC_GC_PROCS of - GcOpAllowed when GcOpAllowed == false; - NeedGC0 == [] -> - {NoGcReq0, NeedGC0}; - _ -> - {NoGcReq0+1, cpc_request_gc(CpcS,NeedGC0)} - end, - - %% Wait for a cpc reply or 'DOWN' message - {NoReq1, NoGcReq2, Pid, Result, KillState1} = cpc_recv(Tag, - NoReq0, - NoGcReq1, - KillState0), - - %% Check the result of the reply - case Result of - aborted -> - %% Operation aborted due to the need to GC in order to - %% determine if the process is referring the module. - %% Schedule the operation for restart allowing GC... - check_proc_code(CpcS, NoReq1, NoGcReq2, [Pid|NeedGC1], KillState1, - Success); - false -> - %% Process not referring the module; done with this process... - check_proc_code(CpcS, NoReq1, NoGcReq2, NeedGC1, KillState1, - Success); - true -> - %% Process referring the module... - case CpcS#cpc_static.hard of - false -> - %% ... and soft check. The whole operation failed so - %% no point continuing; clean up and fail... - check_proc_code(CpcS, NoReq1, NoGcReq2, [], KillState1, - false); - true -> - %% ... and hard check; schedule kill of it... - check_proc_code(CpcS, NoReq1, NoGcReq2, NeedGC1, - cpc_sched_kill(Pid, KillState1), Success) - end; - 'DOWN' -> - %% Handled 'DOWN' message - check_proc_code(CpcS, NoReq1, NoGcReq2, NeedGC1, - KillState1, Success) - end. - -cpc_recv(Tag, NoReq, NoGcReq, #cpc_kill{outstanding = []} = KillState) -> - receive - {check_process_code, {Tag, Pid, GC}, Res} -> - cpc_handle_cpc(NoReq, NoGcReq, GC, Pid, Res, KillState) - end; -cpc_recv(Tag, NoReq, NoGcReq, - #cpc_kill{outstanding = [R0, R1, R2, R3, R4 | _]} = KillState) -> - receive - {'DOWN', R, process, _, _} when R == R0; - R == R1; - R == R2; - R == R3; - R == R4 -> - cpc_handle_down(NoReq, NoGcReq, R, KillState); - {check_process_code, {Tag, Pid, GC}, Res} -> - cpc_handle_cpc(NoReq, NoGcReq, GC, Pid, Res, KillState) - end; -cpc_recv(Tag, NoReq, NoGcReq, #cpc_kill{outstanding = [R|_]} = KillState) -> - receive - {'DOWN', R, process, _, _} -> - cpc_handle_down(NoReq, NoGcReq, R, KillState); - {check_process_code, {Tag, Pid, GC}, Res} -> - cpc_handle_cpc(NoReq, NoGcReq, GC, Pid, Res, KillState) - end. - -cpc_handle_down(NoReq, NoGcReq, R, #cpc_kill{outstanding = Rs, - no_outstanding = N} = KillState) -> - {NoReq, NoGcReq, undefined, 'DOWN', - cpc_sched_kill_waiting(KillState#cpc_kill{outstanding = cpc_list_rm(R, Rs), - no_outstanding = N-1})}. - -cpc_list_rm(R, [R|Rs]) -> - Rs; -cpc_list_rm(R0, [R1|Rs]) -> - [R1|cpc_list_rm(R0, Rs)]. - -cpc_handle_cpc(NoReq, NoGcReq, false, Pid, Res, KillState) -> - {NoReq-1, NoGcReq, Pid, Res, KillState}; -cpc_handle_cpc(NoReq, NoGcReq, true, Pid, Res, KillState) -> - {NoReq, NoGcReq-1, Pid, Res, KillState}. - -cpc_sched_kill_waiting(#cpc_kill{waiting = []} = KillState) -> - KillState; -cpc_sched_kill_waiting(#cpc_kill{outstanding = Rs, - no_outstanding = N, - waiting = [P|Ps]} = KillState) -> - R = erlang:monitor(process, P), - exit(P, kill), - KillState#cpc_kill{outstanding = [R|Rs], - no_outstanding = N+1, - waiting = Ps, - killed = true}. - -cpc_sched_kill(Pid, #cpc_kill{no_outstanding = N, waiting = Pids} = KillState) - when N >= ?MAX_CPC_NO_OUTSTANDING_KILLS -> - KillState#cpc_kill{waiting = [Pid|Pids]}; -cpc_sched_kill(Pid, - #cpc_kill{outstanding = Rs, no_outstanding = N} = KillState) -> - R = erlang:monitor(process, Pid), - exit(Pid, kill), - KillState#cpc_kill{outstanding = [R|Rs], - no_outstanding = N+1, - killed = true}. - -cpc_request(#cpc_static{tag = Tag, module = Mod}, Pid, AllowGc) -> - erlang:check_process_code(Pid, Mod, [{async, {Tag, Pid, AllowGc}}, - {allow_gc, AllowGc}]). - -cpc_request_gc(CpcS, [Pid|Pids]) -> - cpc_request(CpcS, Pid, true), - Pids. - -cpc_init(_CpcS, [], NoReqs) -> - NoReqs; -cpc_init(CpcS, [Pid|Pids], NoReqs) -> - cpc_request(CpcS, Pid, false), - cpc_init(CpcS, Pids, NoReqs+1). - -% end of check_proc_code() implementation. + erts_code_purger:soft_purge(Mod). -is_loaded(M, Db) -> - case ets:lookup(Db, M) of - [{M,File}] -> {file,File}; - [] -> false - end. %% ------------------------------------------------------- %% The on_load functionality. diff --git a/lib/kernel/test/code_SUITE.erl b/lib/kernel/test/code_SUITE.erl index dfcb20d594..071f8d1d3b 100644 --- a/lib/kernel/test/code_SUITE.erl +++ b/lib/kernel/test/code_SUITE.erl @@ -766,6 +766,7 @@ analyse([], [This={M,F,A}|Path], Visited, ErrCnt0) -> OK = [erlang, os, prim_file, erl_prim_loader, init, ets, code_server, lists, lists_sort, unicode, binary, filename, gb_sets, gb_trees, hipe_unified_loader, hipe_bifs, + erts_code_purger, prim_zip, zlib], ErrCnt1 = case lists:member(M, OK) or erlang:is_builtin(M,F,A) of |