1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- S Y S T E M . T A S K _ P R I M I T I V E S . O P E R A T I O N S --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
11 -- GNARL is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
18 -- As a special exception under Section 7 of GPL version 3, you are granted --
19 -- additional permissions described in the GCC Runtime Library Exception, --
20 -- version 3.1, as published by the Free Software Foundation. --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
27 -- GNARL was developed by the GNARL team at Florida State University. --
28 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
30 ------------------------------------------------------------------------------
32 -- This is a NT (native) version of this package
34 -- This package contains all the GNULL primitives that interface directly with
38 -- Turn off polling, we do not want ATC polling to take place during tasking
39 -- operations. It causes infinite loops and other problems.
41 with Ada.Unchecked_Deallocation;
44 with Interfaces.C.Strings;
46 with System.Multiprocessors;
47 with System.Tasking.Debug;
48 with System.OS_Primitives;
49 with System.Task_Info;
50 with System.Interrupt_Management;
51 with System.Win32.Ext;
53 with System.Soft_Links;
54 -- We use System.Soft_Links instead of System.Tasking.Initialization because
55 -- the later is a higher level package that we shouldn't depend on. For
56 -- example when using the restricted run time, it is replaced by
57 -- System.Tasking.Restricted.Stages.
59 package body System.Task_Primitives.Operations is
61 package SSL renames System.Soft_Links;
63 use System.Tasking.Debug;
66 use Interfaces.C.Strings;
67 use System.OS_Interface;
68 use System.Parameters;
69 use System.OS_Primitives;
74 pragma Link_With ("-Xlinker --stack=0x200000,0x1000");
75 -- Change the default stack size (2 MB) for tasking programs on Windows.
76 -- This allows about 1000 tasks running at the same time. Note that
77 -- we set the stack size for non tasking programs on System unit.
78 -- Also note that under Windows XP, we use a Windows XP extension to
79 -- specify the stack size on a per task basis, as done under other OSes.
85 procedure InitializeCriticalSection (pCriticalSection : access RTS_Lock);
86 procedure InitializeCriticalSection
87 (pCriticalSection : access CRITICAL_SECTION);
89 (Stdcall, InitializeCriticalSection, "InitializeCriticalSection");
91 procedure EnterCriticalSection (pCriticalSection : access RTS_Lock);
92 procedure EnterCriticalSection
93 (pCriticalSection : access CRITICAL_SECTION);
94 pragma Import (Stdcall, EnterCriticalSection, "EnterCriticalSection");
96 procedure LeaveCriticalSection (pCriticalSection : access RTS_Lock);
97 procedure LeaveCriticalSection (pCriticalSection : access CRITICAL_SECTION);
98 pragma Import (Stdcall, LeaveCriticalSection, "LeaveCriticalSection");
100 procedure DeleteCriticalSection (pCriticalSection : access RTS_Lock);
101 procedure DeleteCriticalSection
102 (pCriticalSection : access CRITICAL_SECTION);
103 pragma Import (Stdcall, DeleteCriticalSection, "DeleteCriticalSection");
109 Environment_Task_Id : Task_Id;
110 -- A variable to hold Task_Id for the environment task
112 Single_RTS_Lock : aliased RTS_Lock;
113 -- This is a lock to allow only one thread of control in the RTS at
114 -- a time; it is used to execute in mutual exclusion from all other tasks.
115 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
117 Time_Slice_Val : Integer;
118 pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
120 Dispatching_Policy : Character;
121 pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
123 function Get_Policy (Prio : System.Any_Priority) return Character;
124 pragma Import (C, Get_Policy, "__gnat_get_specific_dispatching");
125 -- Get priority specific dispatching policy
127 Foreign_Task_Elaborated : aliased Boolean := True;
128 -- Used to identified fake tasks (i.e., non-Ada Threads)
130 Annex_D : Boolean := False;
131 -- Set to True if running with Annex-D semantics
133 ------------------------------------
134 -- The thread local storage index --
135 ------------------------------------
138 pragma Export (Ada, TlsIndex);
139 -- To ensure that this variable won't be local to this package, since
140 -- in some cases, inlining forces this variable to be global anyway.
148 function Is_Valid_Task return Boolean;
149 pragma Inline (Is_Valid_Task);
150 -- Does executing thread have a TCB?
152 procedure Set (Self_Id : Task_Id);
154 -- Set the self id for the current task
158 package body Specific is
160 function Is_Valid_Task return Boolean is
162 return TlsGetValue (TlsIndex) /= System.Null_Address;
165 procedure Set (Self_Id : Task_Id) is
168 Succeeded := TlsSetValue (TlsIndex, To_Address (Self_Id));
169 pragma Assert (Succeeded = Win32.TRUE);
174 ---------------------------------
175 -- Support for foreign threads --
176 ---------------------------------
178 function Register_Foreign_Thread (Thread : Thread_Id) return Task_Id;
179 -- Allocate and Initialize a new ATCB for the current Thread
181 function Register_Foreign_Thread
182 (Thread : Thread_Id) return Task_Id is separate;
184 ----------------------------------
185 -- Condition Variable Functions --
186 ----------------------------------
188 procedure Initialize_Cond (Cond : not null access Condition_Variable);
189 -- Initialize given condition variable Cond
191 procedure Finalize_Cond (Cond : not null access Condition_Variable);
192 -- Finalize given condition variable Cond
194 procedure Cond_Signal (Cond : not null access Condition_Variable);
195 -- Signal condition variable Cond
198 (Cond : not null access Condition_Variable;
199 L : not null access RTS_Lock);
200 -- Wait on conditional variable Cond, using lock L
202 procedure Cond_Timed_Wait
203 (Cond : not null access Condition_Variable;
204 L : not null access RTS_Lock;
206 Timed_Out : out Boolean;
207 Status : out Integer);
208 -- Do timed wait on condition variable Cond using lock L. The duration
209 -- of the timed wait is given by Rel_Time. When the condition is
210 -- signalled, Timed_Out shows whether or not a time out occurred.
211 -- Status is only valid if Timed_Out is False, in which case it
212 -- shows whether Cond_Timed_Wait completed successfully.
214 ---------------------
215 -- Initialize_Cond --
216 ---------------------
218 procedure Initialize_Cond (Cond : not null access Condition_Variable) is
221 hEvent := CreateEvent (null, Win32.TRUE, Win32.FALSE, Null_Ptr);
222 pragma Assert (hEvent /= 0);
223 Cond.all := Condition_Variable (hEvent);
230 -- No such problem here, DosCloseEventSem has been derived.
231 -- What does such refer to in above comment???
233 procedure Finalize_Cond (Cond : not null access Condition_Variable) is
236 Result := CloseHandle (HANDLE (Cond.all));
237 pragma Assert (Result = Win32.TRUE);
244 procedure Cond_Signal (Cond : not null access Condition_Variable) is
247 Result := SetEvent (HANDLE (Cond.all));
248 pragma Assert (Result = Win32.TRUE);
255 -- Pre-condition: Cond is posted
258 -- Post-condition: Cond is posted
262 (Cond : not null access Condition_Variable;
263 L : not null access RTS_Lock)
269 -- Must reset Cond BEFORE L is unlocked
271 Result_Bool := ResetEvent (HANDLE (Cond.all));
272 pragma Assert (Result_Bool = Win32.TRUE);
273 Unlock (L, Global_Lock => True);
275 -- No problem if we are interrupted here: if the condition is signaled,
276 -- WaitForSingleObject will simply not block
278 Result := WaitForSingleObject (HANDLE (Cond.all), Wait_Infinite);
279 pragma Assert (Result = 0);
281 Write_Lock (L, Global_Lock => True);
284 ---------------------
285 -- Cond_Timed_Wait --
286 ---------------------
288 -- Pre-condition: Cond is posted
291 -- Post-condition: Cond is posted
294 procedure Cond_Timed_Wait
295 (Cond : not null access Condition_Variable;
296 L : not null access RTS_Lock;
298 Timed_Out : out Boolean;
299 Status : out Integer)
301 Time_Out_Max : constant DWORD := 16#FFFF0000#;
302 -- NT 4 can't handle excessive timeout values (e.g. DWORD'Last - 1)
309 -- Must reset Cond BEFORE L is unlocked
311 Result := ResetEvent (HANDLE (Cond.all));
312 pragma Assert (Result = Win32.TRUE);
313 Unlock (L, Global_Lock => True);
315 -- No problem if we are interrupted here: if the condition is signaled,
316 -- WaitForSingleObject will simply not block.
318 if Rel_Time <= 0.0 then
324 (if Rel_Time >= Duration (Time_Out_Max) / 1000
326 else DWORD (Rel_Time * 1000));
328 Wait_Result := WaitForSingleObject (HANDLE (Cond.all), Time_Out);
330 if Wait_Result = WAIT_TIMEOUT then
338 Write_Lock (L, Global_Lock => True);
340 -- Ensure post-condition
343 Result := SetEvent (HANDLE (Cond.all));
344 pragma Assert (Result = Win32.TRUE);
347 Status := Integer (Wait_Result);
354 -- The underlying thread system sets a guard page at the bottom of a thread
355 -- stack, so nothing is needed.
356 -- ??? Check the comment above
358 procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
359 pragma Unreferenced (T, On);
368 function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is
370 return T.Common.LL.Thread;
377 function Self return Task_Id is
378 Self_Id : constant Task_Id := To_Task_Id (TlsGetValue (TlsIndex));
380 if Self_Id = null then
381 return Register_Foreign_Thread (GetCurrentThread);
387 ---------------------
388 -- Initialize_Lock --
389 ---------------------
391 -- Note: mutexes and cond_variables needed per-task basis are initialized
392 -- in Initialize_TCB and the Storage_Error is handled. Other mutexes (such
393 -- as RTS_Lock, Memory_Lock...) used in the RTS is initialized before any
394 -- status change of RTS. Therefore raising Storage_Error in the following
395 -- routines should be able to be handled safely.
397 procedure Initialize_Lock
398 (Prio : System.Any_Priority;
399 L : not null access Lock)
402 InitializeCriticalSection (L.Mutex'Access);
403 L.Owner_Priority := 0;
407 procedure Initialize_Lock
408 (L : not null access RTS_Lock; Level : Lock_Level)
410 pragma Unreferenced (Level);
412 InitializeCriticalSection (L);
419 procedure Finalize_Lock (L : not null access Lock) is
421 DeleteCriticalSection (L.Mutex'Access);
424 procedure Finalize_Lock (L : not null access RTS_Lock) is
426 DeleteCriticalSection (L);
434 (L : not null access Lock; Ceiling_Violation : out Boolean) is
436 L.Owner_Priority := Get_Priority (Self);
438 if L.Priority < L.Owner_Priority then
439 Ceiling_Violation := True;
443 EnterCriticalSection (L.Mutex'Access);
445 Ceiling_Violation := False;
449 (L : not null access RTS_Lock;
450 Global_Lock : Boolean := False)
453 if not Single_Lock or else Global_Lock then
454 EnterCriticalSection (L);
458 procedure Write_Lock (T : Task_Id) is
460 if not Single_Lock then
461 EnterCriticalSection (T.Common.LL.L'Access);
470 (L : not null access Lock; Ceiling_Violation : out Boolean) is
472 Write_Lock (L, Ceiling_Violation);
479 procedure Unlock (L : not null access Lock) is
481 LeaveCriticalSection (L.Mutex'Access);
485 (L : not null access RTS_Lock; Global_Lock : Boolean := False) is
487 if not Single_Lock or else Global_Lock then
488 LeaveCriticalSection (L);
492 procedure Unlock (T : Task_Id) is
494 if not Single_Lock then
495 LeaveCriticalSection (T.Common.LL.L'Access);
503 -- Dynamic priority ceilings are not supported by the underlying system
505 procedure Set_Ceiling
506 (L : not null access Lock;
507 Prio : System.Any_Priority)
509 pragma Unreferenced (L, Prio);
520 Reason : System.Tasking.Task_States)
522 pragma Unreferenced (Reason);
525 pragma Assert (Self_ID = Self);
528 Cond_Wait (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access);
530 Cond_Wait (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access);
533 if Self_ID.Deferral_Level = 0
534 and then Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
537 raise Standard'Abort_Signal;
545 -- This is for use within the run-time system, so abort is assumed to be
546 -- already deferred, and the caller should be holding its own ATCB lock.
548 procedure Timed_Sleep
551 Mode : ST.Delay_Modes;
552 Reason : System.Tasking.Task_States;
553 Timedout : out Boolean;
554 Yielded : out Boolean)
556 pragma Unreferenced (Reason);
557 Check_Time : Duration := Monotonic_Clock;
562 pragma Unreferenced (Result);
564 Local_Timedout : Boolean;
570 if Mode = Relative then
572 Abs_Time := Duration'Min (Time, Max_Sensible_Delay) + Check_Time;
574 Rel_Time := Time - Check_Time;
578 if Rel_Time > 0.0 then
580 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
584 (Self_ID.Common.LL.CV'Access,
585 Single_RTS_Lock'Access,
586 Rel_Time, Local_Timedout, Result);
589 (Self_ID.Common.LL.CV'Access,
590 Self_ID.Common.LL.L'Access,
591 Rel_Time, Local_Timedout, Result);
594 Check_Time := Monotonic_Clock;
595 exit when Abs_Time <= Check_Time;
597 if not Local_Timedout then
599 -- Somebody may have called Wakeup for us
605 Rel_Time := Abs_Time - Check_Time;
614 procedure Timed_Delay
617 Mode : ST.Delay_Modes)
619 Check_Time : Duration := Monotonic_Clock;
625 pragma Unreferenced (Timedout, Result);
632 Write_Lock (Self_ID);
634 if Mode = Relative then
636 Abs_Time := Time + Check_Time;
638 Rel_Time := Time - Check_Time;
642 if Rel_Time > 0.0 then
643 Self_ID.Common.State := Delay_Sleep;
646 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
650 (Self_ID.Common.LL.CV'Access,
651 Single_RTS_Lock'Access,
652 Rel_Time, Timedout, Result);
655 (Self_ID.Common.LL.CV'Access,
656 Self_ID.Common.LL.L'Access,
657 Rel_Time, Timedout, Result);
660 Check_Time := Monotonic_Clock;
661 exit when Abs_Time <= Check_Time;
663 Rel_Time := Abs_Time - Check_Time;
666 Self_ID.Common.State := Runnable;
682 procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is
683 pragma Unreferenced (Reason);
685 Cond_Signal (T.Common.LL.CV'Access);
692 procedure Yield (Do_Yield : Boolean := True) is
698 -- If running with Annex-D semantics we need a delay
699 -- above 0 milliseconds here otherwise processes give
700 -- enough time to the other tasks to have a chance to
703 -- This makes cxd8002 ACATS pass on Windows.
713 type Prio_Array_Type is array (System.Any_Priority) of Integer;
714 pragma Atomic_Components (Prio_Array_Type);
716 Prio_Array : Prio_Array_Type;
717 -- Global array containing the id of the currently running task for
720 -- Note: we assume that we are on a single processor with run-til-blocked
723 procedure Set_Priority
725 Prio : System.Any_Priority;
726 Loss_Of_Inheritance : Boolean := False)
729 Array_Item : Integer;
732 Res := SetThreadPriority
733 (T.Common.LL.Thread, Interfaces.C.int (Underlying_Priorities (Prio)));
734 pragma Assert (Res = Win32.TRUE);
736 if Dispatching_Policy = 'F' or else Get_Policy (Prio) = 'F' then
738 -- Annex D requirement [RM D.2.2 par. 9]:
739 -- If the task drops its priority due to the loss of inherited
740 -- priority, it is added at the head of the ready queue for its
741 -- new active priority.
743 if Loss_Of_Inheritance
744 and then Prio < T.Common.Current_Priority
746 Array_Item := Prio_Array (T.Common.Base_Priority) + 1;
747 Prio_Array (T.Common.Base_Priority) := Array_Item;
750 -- Let some processes a chance to arrive
754 -- Then wait for our turn to proceed
756 exit when Array_Item = Prio_Array (T.Common.Base_Priority)
757 or else Prio_Array (T.Common.Base_Priority) = 1;
760 Prio_Array (T.Common.Base_Priority) :=
761 Prio_Array (T.Common.Base_Priority) - 1;
765 T.Common.Current_Priority := Prio;
772 function Get_Priority (T : Task_Id) return System.Any_Priority is
774 return T.Common.Current_Priority;
781 -- There were two paths were we needed to call Enter_Task :
782 -- 1) from System.Task_Primitives.Operations.Initialize
783 -- 2) from System.Tasking.Stages.Task_Wrapper
785 -- The thread initialisation has to be done only for the first case
787 -- This is because the GetCurrentThread NT call does not return the real
788 -- thread handler but only a "pseudo" one. It is not possible to release
789 -- the thread handle and free the system resources from this "pseudo"
790 -- handle. So we really want to keep the real thread handle set in
791 -- System.Task_Primitives.Operations.Create_Task during thread creation.
793 procedure Enter_Task (Self_ID : Task_Id) is
794 procedure Init_Float;
795 pragma Import (C, Init_Float, "__gnat_init_float");
796 -- Properly initializes the FPU for x86 systems
798 procedure Get_Stack_Bounds (Base : Address; Limit : Address);
799 pragma Import (C, Get_Stack_Bounds, "__gnat_get_stack_bounds");
800 -- Get stack boundaries
802 Specific.Set (Self_ID);
805 if Self_ID.Common.Task_Info /= null
807 Self_ID.Common.Task_Info.CPU >= CPU_Number (Number_Of_Processors)
809 raise Invalid_CPU_Number;
812 Self_ID.Common.LL.Thread_Id := GetCurrentThreadId;
815 (Self_ID.Common.Compiler_Data.Pri_Stack_Info.Base'Address,
816 Self_ID.Common.Compiler_Data.Pri_Stack_Info.Limit'Address);
823 function New_ATCB (Entry_Num : Task_Entry_Index) return Task_Id is
825 return new Ada_Task_Control_Block (Entry_Num);
832 function Is_Valid_Task return Boolean renames Specific.Is_Valid_Task;
834 -----------------------------
835 -- Register_Foreign_Thread --
836 -----------------------------
838 function Register_Foreign_Thread return Task_Id is
840 if Is_Valid_Task then
843 return Register_Foreign_Thread (GetCurrentThread);
845 end Register_Foreign_Thread;
851 procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is
853 -- Initialize thread ID to 0, this is needed to detect threads that
854 -- are not yet activated.
856 Self_ID.Common.LL.Thread := 0;
858 Initialize_Cond (Self_ID.Common.LL.CV'Access);
860 if not Single_Lock then
861 Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level);
871 procedure Create_Task
873 Wrapper : System.Address;
874 Stack_Size : System.Parameters.Size_Type;
875 Priority : System.Any_Priority;
876 Succeeded : out Boolean)
878 Initial_Stack_Size : constant := 1024;
879 -- We set the initial stack size to 1024. On Windows version prior to XP
880 -- there is no way to fix a task stack size. Only the initial stack size
881 -- can be set, the operating system will raise the task stack size if
884 function Is_Windows_XP return Integer;
885 pragma Import (C, Is_Windows_XP, "__gnat_is_windows_xp");
886 -- Returns 1 if running on Windows XP
889 TaskId : aliased DWORD;
890 pTaskParameter : Win32.PVOID;
892 Entry_Point : PTHREAD_START_ROUTINE;
894 use type System.Multiprocessors.CPU_Range;
897 pTaskParameter := To_Address (T);
899 Entry_Point := To_PTHREAD_START_ROUTINE (Wrapper);
901 if Is_Windows_XP = 1 then
902 hTask := CreateThread
907 DWORD (Create_Suspended) or
908 DWORD (Stack_Size_Param_Is_A_Reservation),
909 TaskId'Unchecked_Access);
911 hTask := CreateThread
916 DWORD (Create_Suspended),
917 TaskId'Unchecked_Access);
920 -- Step 1: Create the thread in blocked mode
927 -- Step 2: set its TCB
929 T.Common.LL.Thread := hTask;
931 -- Note: it would be useful to initialize Thread_Id right away to avoid
932 -- a race condition in gdb where Thread_ID may not have the right value
933 -- yet, but GetThreadId is a Vista specific API, not available under XP:
934 -- T.Common.LL.Thread_Id := GetThreadId (hTask); so instead we set the
935 -- field to 0 to avoid having a random value. Thread_Id is initialized
936 -- in Enter_Task anyway.
938 T.Common.LL.Thread_Id := 0;
940 -- Step 3: set its priority (child has inherited priority from parent)
942 Set_Priority (T, Priority);
944 if Time_Slice_Val = 0
945 or else Dispatching_Policy = 'F'
946 or else Get_Policy (Priority) = 'F'
948 -- Here we need Annex D semantics so we disable the NT priority
949 -- boost. A priority boost is temporarily given by the system to
950 -- a thread when it is taken out of a wait state.
952 SetThreadPriorityBoost (hTask, DisablePriorityBoost => Win32.TRUE);
955 -- Step 4: Handle pragma CPU and Task_Info
957 if T.Common.Base_CPU /= System.Multiprocessors.Not_A_Specific_CPU then
959 -- The CPU numbering in pragma CPU starts at 1 while the subprogram
960 -- to set the affinity starts at 0, therefore we must substract 1.
962 Result := SetThreadIdealProcessor
963 (hTask, ProcessorId (T.Common.Base_CPU) - 1);
964 pragma Assert (Result = 1);
966 elsif T.Common.Task_Info /= null then
967 if T.Common.Task_Info.CPU /= Task_Info.Any_CPU then
968 Result := SetThreadIdealProcessor (hTask, T.Common.Task_Info.CPU);
969 pragma Assert (Result = 1);
973 -- Step 5: Now, start it for good
975 Result := ResumeThread (hTask);
976 pragma Assert (Result = 1);
978 Succeeded := Result = 1;
985 procedure Finalize_TCB (T : Task_Id) is
986 Self_ID : Task_Id := T;
989 Is_Self : constant Boolean := T = Self;
991 procedure Free is new
992 Ada.Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id);
995 if not Single_Lock then
996 Finalize_Lock (T.Common.LL.L'Access);
999 Finalize_Cond (T.Common.LL.CV'Access);
1001 if T.Known_Tasks_Index /= -1 then
1002 Known_Tasks (T.Known_Tasks_Index) := null;
1005 if Self_ID.Common.LL.Thread /= 0 then
1007 -- This task has been activated. Wait for the thread to terminate
1008 -- then close it. This is needed to release system resources.
1010 Result := WaitForSingleObject (T.Common.LL.Thread, Wait_Infinite);
1011 pragma Assert (Result /= WAIT_FAILED);
1012 Succeeded := CloseHandle (T.Common.LL.Thread);
1013 pragma Assert (Succeeded = Win32.TRUE);
1019 Specific.Set (null);
1027 procedure Exit_Task is
1029 Specific.Set (null);
1036 procedure Abort_Task (T : Task_Id) is
1037 pragma Unreferenced (T);
1042 ----------------------
1043 -- Environment_Task --
1044 ----------------------
1046 function Environment_Task return Task_Id is
1048 return Environment_Task_Id;
1049 end Environment_Task;
1055 procedure Lock_RTS is
1057 Write_Lock (Single_RTS_Lock'Access, Global_Lock => True);
1064 procedure Unlock_RTS is
1066 Unlock (Single_RTS_Lock'Access, Global_Lock => True);
1073 procedure Initialize (Environment_Task : Task_Id) is
1075 pragma Unreferenced (Discard);
1079 use type System.Multiprocessors.CPU_Range;
1082 Environment_Task_Id := Environment_Task;
1083 OS_Primitives.Initialize;
1084 Interrupt_Management.Initialize;
1086 if Time_Slice_Val = 0 or else Dispatching_Policy = 'F' then
1087 -- Here we need Annex D semantics, switch the current process to the
1088 -- Realtime_Priority_Class.
1090 Discard := OS_Interface.SetPriorityClass
1091 (GetCurrentProcess, Realtime_Priority_Class);
1096 TlsIndex := TlsAlloc;
1098 -- Initialize the lock used to synchronize chain of all ATCBs
1100 Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level);
1102 Environment_Task.Common.LL.Thread := GetCurrentThread;
1104 -- Make environment task known here because it doesn't go through
1105 -- Activate_Tasks, which does it for all other tasks.
1107 Known_Tasks (Known_Tasks'First) := Environment_Task;
1108 Environment_Task.Known_Tasks_Index := Known_Tasks'First;
1110 Enter_Task (Environment_Task);
1112 -- pragma CPU for the environment task
1114 if Environment_Task.Common.Base_CPU /=
1115 System.Multiprocessors.Not_A_Specific_CPU
1117 -- The CPU numbering in pragma CPU starts at 1 while the subprogram
1118 -- to set the affinity starts at 0, therefore we must substract 1.
1121 SetThreadIdealProcessor
1122 (Environment_Task.Common.LL.Thread,
1123 ProcessorId (Environment_Task.Common.Base_CPU) - 1);
1124 pragma Assert (Result = 1);
1128 ---------------------
1129 -- Monotonic_Clock --
1130 ---------------------
1132 function Monotonic_Clock return Duration
1133 renames System.OS_Primitives.Monotonic_Clock;
1139 function RT_Resolution return Duration is
1141 return 0.000_001; -- 1 micro-second
1148 procedure Initialize (S : in out Suspension_Object) is
1150 -- Initialize internal state. It is always initialized to False (ARM
1156 -- Initialize internal mutex
1158 InitializeCriticalSection (S.L'Access);
1160 -- Initialize internal condition variable
1162 S.CV := CreateEvent (null, Win32.TRUE, Win32.FALSE, Null_Ptr);
1163 pragma Assert (S.CV /= 0);
1170 procedure Finalize (S : in out Suspension_Object) is
1174 -- Destroy internal mutex
1176 DeleteCriticalSection (S.L'Access);
1178 -- Destroy internal condition variable
1180 Result := CloseHandle (S.CV);
1181 pragma Assert (Result = Win32.TRUE);
1188 function Current_State (S : Suspension_Object) return Boolean is
1190 -- We do not want to use lock on this read operation. State is marked
1191 -- as Atomic so that we ensure that the value retrieved is correct.
1200 procedure Set_False (S : in out Suspension_Object) is
1202 SSL.Abort_Defer.all;
1204 EnterCriticalSection (S.L'Access);
1208 LeaveCriticalSection (S.L'Access);
1210 SSL.Abort_Undefer.all;
1217 procedure Set_True (S : in out Suspension_Object) is
1220 SSL.Abort_Defer.all;
1222 EnterCriticalSection (S.L'Access);
1224 -- If there is already a task waiting on this suspension object then
1225 -- we resume it, leaving the state of the suspension object to False,
1226 -- as it is specified in ARM D.10 par. 9. Otherwise, it just leaves
1227 -- the state to True.
1233 Result := SetEvent (S.CV);
1234 pragma Assert (Result = Win32.TRUE);
1239 LeaveCriticalSection (S.L'Access);
1241 SSL.Abort_Undefer.all;
1244 ------------------------
1245 -- Suspend_Until_True --
1246 ------------------------
1248 procedure Suspend_Until_True (S : in out Suspension_Object) is
1253 SSL.Abort_Defer.all;
1255 EnterCriticalSection (S.L'Access);
1258 -- Program_Error must be raised upon calling Suspend_Until_True
1259 -- if another task is already waiting on that suspension object
1260 -- (ARM D.10 par. 10).
1262 LeaveCriticalSection (S.L'Access);
1264 SSL.Abort_Undefer.all;
1266 raise Program_Error;
1268 -- Suspend the task if the state is False. Otherwise, the task
1269 -- continues its execution, and the state of the suspension object
1270 -- is set to False (ARM D.10 par. 9).
1275 LeaveCriticalSection (S.L'Access);
1277 SSL.Abort_Undefer.all;
1281 -- Must reset CV BEFORE L is unlocked
1283 Result_Bool := ResetEvent (S.CV);
1284 pragma Assert (Result_Bool = Win32.TRUE);
1286 LeaveCriticalSection (S.L'Access);
1288 SSL.Abort_Undefer.all;
1290 Result := WaitForSingleObject (S.CV, Wait_Infinite);
1291 pragma Assert (Result = 0);
1294 end Suspend_Until_True;
1300 -- Dummy versions. The only currently working versions is for solaris
1303 function Check_Exit (Self_ID : ST.Task_Id) return Boolean is
1304 pragma Unreferenced (Self_ID);
1309 --------------------
1310 -- Check_No_Locks --
1311 --------------------
1313 function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is
1314 pragma Unreferenced (Self_ID);
1323 function Suspend_Task
1325 Thread_Self : Thread_Id) return Boolean
1328 if T.Common.LL.Thread /= Thread_Self then
1329 return SuspendThread (T.Common.LL.Thread) = NO_ERROR;
1339 function Resume_Task
1341 Thread_Self : Thread_Id) return Boolean
1344 if T.Common.LL.Thread /= Thread_Self then
1345 return ResumeThread (T.Common.LL.Thread) = NO_ERROR;
1351 --------------------
1352 -- Stop_All_Tasks --
1353 --------------------
1355 procedure Stop_All_Tasks is
1364 function Stop_Task (T : ST.Task_Id) return Boolean is
1365 pragma Unreferenced (T);
1374 function Continue_Task (T : ST.Task_Id) return Boolean is
1375 pragma Unreferenced (T);
1380 end System.Task_Primitives.Operations;