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) 1992-2011, 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;
52 with System.Float_Control;
54 with System.Soft_Links;
55 -- We use System.Soft_Links instead of System.Tasking.Initialization because
56 -- the later is a higher level package that we shouldn't depend on. For
57 -- example when using the restricted run time, it is replaced by
58 -- System.Tasking.Restricted.Stages.
60 package body System.Task_Primitives.Operations is
62 package SSL renames System.Soft_Links;
64 use System.Tasking.Debug;
67 use Interfaces.C.Strings;
68 use System.OS_Interface;
69 use System.Parameters;
70 use System.OS_Primitives;
75 pragma Link_With ("-Xlinker --stack=0x200000,0x1000");
76 -- Change the default stack size (2 MB) for tasking programs on Windows.
77 -- This allows about 1000 tasks running at the same time. Note that
78 -- we set the stack size for non tasking programs on System unit.
79 -- Also note that under Windows XP, we use a Windows XP extension to
80 -- specify the stack size on a per task basis, as done under other OSes.
86 procedure InitializeCriticalSection (pCriticalSection : access RTS_Lock);
87 procedure InitializeCriticalSection
88 (pCriticalSection : access CRITICAL_SECTION);
90 (Stdcall, InitializeCriticalSection, "InitializeCriticalSection");
92 procedure EnterCriticalSection (pCriticalSection : access RTS_Lock);
93 procedure EnterCriticalSection
94 (pCriticalSection : access CRITICAL_SECTION);
95 pragma Import (Stdcall, EnterCriticalSection, "EnterCriticalSection");
97 procedure LeaveCriticalSection (pCriticalSection : access RTS_Lock);
98 procedure LeaveCriticalSection (pCriticalSection : access CRITICAL_SECTION);
99 pragma Import (Stdcall, LeaveCriticalSection, "LeaveCriticalSection");
101 procedure DeleteCriticalSection (pCriticalSection : access RTS_Lock);
102 procedure DeleteCriticalSection
103 (pCriticalSection : access CRITICAL_SECTION);
104 pragma Import (Stdcall, DeleteCriticalSection, "DeleteCriticalSection");
110 Environment_Task_Id : Task_Id;
111 -- A variable to hold Task_Id for the environment task
113 Single_RTS_Lock : aliased RTS_Lock;
114 -- This is a lock to allow only one thread of control in the RTS at
115 -- a time; it is used to execute in mutual exclusion from all other tasks.
116 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
118 Time_Slice_Val : Integer;
119 pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
121 Dispatching_Policy : Character;
122 pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
124 function Get_Policy (Prio : System.Any_Priority) return Character;
125 pragma Import (C, Get_Policy, "__gnat_get_specific_dispatching");
126 -- Get priority specific dispatching policy
128 Foreign_Task_Elaborated : aliased Boolean := True;
129 -- Used to identified fake tasks (i.e., non-Ada Threads)
131 Annex_D : Boolean := False;
132 -- Set to True if running with Annex-D semantics
134 ------------------------------------
135 -- The thread local storage index --
136 ------------------------------------
139 pragma Export (Ada, TlsIndex);
140 -- To ensure that this variable won't be local to this package, since
141 -- in some cases, inlining forces this variable to be global anyway.
149 function Is_Valid_Task return Boolean;
150 pragma Inline (Is_Valid_Task);
151 -- Does executing thread have a TCB?
153 procedure Set (Self_Id : Task_Id);
155 -- Set the self id for the current task
159 package body Specific is
161 function Is_Valid_Task return Boolean is
163 return TlsGetValue (TlsIndex) /= System.Null_Address;
166 procedure Set (Self_Id : Task_Id) is
169 Succeeded := TlsSetValue (TlsIndex, To_Address (Self_Id));
170 pragma Assert (Succeeded = Win32.TRUE);
175 ---------------------------------
176 -- Support for foreign threads --
177 ---------------------------------
179 function Register_Foreign_Thread (Thread : Thread_Id) return Task_Id;
180 -- Allocate and Initialize a new ATCB for the current Thread
182 function Register_Foreign_Thread
183 (Thread : Thread_Id) return Task_Id is separate;
185 ----------------------------------
186 -- Condition Variable Functions --
187 ----------------------------------
189 procedure Initialize_Cond (Cond : not null access Condition_Variable);
190 -- Initialize given condition variable Cond
192 procedure Finalize_Cond (Cond : not null access Condition_Variable);
193 -- Finalize given condition variable Cond
195 procedure Cond_Signal (Cond : not null access Condition_Variable);
196 -- Signal condition variable Cond
199 (Cond : not null access Condition_Variable;
200 L : not null access RTS_Lock);
201 -- Wait on conditional variable Cond, using lock L
203 procedure Cond_Timed_Wait
204 (Cond : not null access Condition_Variable;
205 L : not null access RTS_Lock;
207 Timed_Out : out Boolean;
208 Status : out Integer);
209 -- Do timed wait on condition variable Cond using lock L. The duration
210 -- of the timed wait is given by Rel_Time. When the condition is
211 -- signalled, Timed_Out shows whether or not a time out occurred.
212 -- Status is only valid if Timed_Out is False, in which case it
213 -- shows whether Cond_Timed_Wait completed successfully.
215 ---------------------
216 -- Initialize_Cond --
217 ---------------------
219 procedure Initialize_Cond (Cond : not null access Condition_Variable) is
222 hEvent := CreateEvent (null, Win32.TRUE, Win32.FALSE, Null_Ptr);
223 pragma Assert (hEvent /= 0);
224 Cond.all := Condition_Variable (hEvent);
231 -- No such problem here, DosCloseEventSem has been derived.
232 -- What does such refer to in above comment???
234 procedure Finalize_Cond (Cond : not null access Condition_Variable) is
237 Result := CloseHandle (HANDLE (Cond.all));
238 pragma Assert (Result = Win32.TRUE);
245 procedure Cond_Signal (Cond : not null access Condition_Variable) is
248 Result := SetEvent (HANDLE (Cond.all));
249 pragma Assert (Result = Win32.TRUE);
256 -- Pre-condition: Cond is posted
259 -- Post-condition: Cond is posted
263 (Cond : not null access Condition_Variable;
264 L : not null access RTS_Lock)
270 -- Must reset Cond BEFORE L is unlocked
272 Result_Bool := ResetEvent (HANDLE (Cond.all));
273 pragma Assert (Result_Bool = Win32.TRUE);
274 Unlock (L, Global_Lock => True);
276 -- No problem if we are interrupted here: if the condition is signaled,
277 -- WaitForSingleObject will simply not block
279 Result := WaitForSingleObject (HANDLE (Cond.all), Wait_Infinite);
280 pragma Assert (Result = 0);
282 Write_Lock (L, Global_Lock => True);
285 ---------------------
286 -- Cond_Timed_Wait --
287 ---------------------
289 -- Pre-condition: Cond is posted
292 -- Post-condition: Cond is posted
295 procedure Cond_Timed_Wait
296 (Cond : not null access Condition_Variable;
297 L : not null access RTS_Lock;
299 Timed_Out : out Boolean;
300 Status : out Integer)
302 Time_Out_Max : constant DWORD := 16#FFFF0000#;
303 -- NT 4 can't handle excessive timeout values (e.g. DWORD'Last - 1)
310 -- Must reset Cond BEFORE L is unlocked
312 Result := ResetEvent (HANDLE (Cond.all));
313 pragma Assert (Result = Win32.TRUE);
314 Unlock (L, Global_Lock => True);
316 -- No problem if we are interrupted here: if the condition is signaled,
317 -- WaitForSingleObject will simply not block.
319 if Rel_Time <= 0.0 then
325 (if Rel_Time >= Duration (Time_Out_Max) / 1000
327 else DWORD (Rel_Time * 1000));
329 Wait_Result := WaitForSingleObject (HANDLE (Cond.all), Time_Out);
331 if Wait_Result = WAIT_TIMEOUT then
339 Write_Lock (L, Global_Lock => True);
341 -- Ensure post-condition
344 Result := SetEvent (HANDLE (Cond.all));
345 pragma Assert (Result = Win32.TRUE);
348 Status := Integer (Wait_Result);
355 -- The underlying thread system sets a guard page at the bottom of a thread
356 -- stack, so nothing is needed.
357 -- ??? Check the comment above
359 procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
360 pragma Unreferenced (T, On);
369 function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is
371 return T.Common.LL.Thread;
378 function Self return Task_Id is
379 Self_Id : constant Task_Id := To_Task_Id (TlsGetValue (TlsIndex));
381 if Self_Id = null then
382 return Register_Foreign_Thread (GetCurrentThread);
388 ---------------------
389 -- Initialize_Lock --
390 ---------------------
392 -- Note: mutexes and cond_variables needed per-task basis are initialized
393 -- in Initialize_TCB and the Storage_Error is handled. Other mutexes (such
394 -- as RTS_Lock, Memory_Lock...) used in the RTS is initialized before any
395 -- status change of RTS. Therefore raising Storage_Error in the following
396 -- routines should be able to be handled safely.
398 procedure Initialize_Lock
399 (Prio : System.Any_Priority;
400 L : not null access Lock)
403 InitializeCriticalSection (L.Mutex'Access);
404 L.Owner_Priority := 0;
408 procedure Initialize_Lock
409 (L : not null access RTS_Lock; Level : Lock_Level)
411 pragma Unreferenced (Level);
413 InitializeCriticalSection (L);
420 procedure Finalize_Lock (L : not null access Lock) is
422 DeleteCriticalSection (L.Mutex'Access);
425 procedure Finalize_Lock (L : not null access RTS_Lock) is
427 DeleteCriticalSection (L);
435 (L : not null access Lock; Ceiling_Violation : out Boolean) is
437 L.Owner_Priority := Get_Priority (Self);
439 if L.Priority < L.Owner_Priority then
440 Ceiling_Violation := True;
444 EnterCriticalSection (L.Mutex'Access);
446 Ceiling_Violation := False;
450 (L : not null access RTS_Lock;
451 Global_Lock : Boolean := False)
454 if not Single_Lock or else Global_Lock then
455 EnterCriticalSection (L);
459 procedure Write_Lock (T : Task_Id) is
461 if not Single_Lock then
462 EnterCriticalSection (T.Common.LL.L'Access);
471 (L : not null access Lock; Ceiling_Violation : out Boolean) is
473 Write_Lock (L, Ceiling_Violation);
480 procedure Unlock (L : not null access Lock) is
482 LeaveCriticalSection (L.Mutex'Access);
486 (L : not null access RTS_Lock; Global_Lock : Boolean := False) is
488 if not Single_Lock or else Global_Lock then
489 LeaveCriticalSection (L);
493 procedure Unlock (T : Task_Id) is
495 if not Single_Lock then
496 LeaveCriticalSection (T.Common.LL.L'Access);
504 -- Dynamic priority ceilings are not supported by the underlying system
506 procedure Set_Ceiling
507 (L : not null access Lock;
508 Prio : System.Any_Priority)
510 pragma Unreferenced (L, Prio);
521 Reason : System.Tasking.Task_States)
523 pragma Unreferenced (Reason);
526 pragma Assert (Self_ID = Self);
529 Cond_Wait (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access);
531 Cond_Wait (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access);
534 if Self_ID.Deferral_Level = 0
535 and then Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
538 raise Standard'Abort_Signal;
546 -- This is for use within the run-time system, so abort is assumed to be
547 -- already deferred, and the caller should be holding its own ATCB lock.
549 procedure Timed_Sleep
552 Mode : ST.Delay_Modes;
553 Reason : System.Tasking.Task_States;
554 Timedout : out Boolean;
555 Yielded : out Boolean)
557 pragma Unreferenced (Reason);
558 Check_Time : Duration := Monotonic_Clock;
563 pragma Unreferenced (Result);
565 Local_Timedout : Boolean;
571 if Mode = Relative then
573 Abs_Time := Duration'Min (Time, Max_Sensible_Delay) + Check_Time;
575 Rel_Time := Time - Check_Time;
579 if Rel_Time > 0.0 then
581 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
585 (Self_ID.Common.LL.CV'Access,
586 Single_RTS_Lock'Access,
587 Rel_Time, Local_Timedout, Result);
590 (Self_ID.Common.LL.CV'Access,
591 Self_ID.Common.LL.L'Access,
592 Rel_Time, Local_Timedout, Result);
595 Check_Time := Monotonic_Clock;
596 exit when Abs_Time <= Check_Time;
598 if not Local_Timedout then
600 -- Somebody may have called Wakeup for us
606 Rel_Time := Abs_Time - Check_Time;
615 procedure Timed_Delay
618 Mode : ST.Delay_Modes)
620 Check_Time : Duration := Monotonic_Clock;
626 pragma Unreferenced (Timedout, Result);
633 Write_Lock (Self_ID);
635 if Mode = Relative then
637 Abs_Time := Time + Check_Time;
639 Rel_Time := Time - Check_Time;
643 if Rel_Time > 0.0 then
644 Self_ID.Common.State := Delay_Sleep;
647 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
651 (Self_ID.Common.LL.CV'Access,
652 Single_RTS_Lock'Access,
653 Rel_Time, Timedout, Result);
656 (Self_ID.Common.LL.CV'Access,
657 Self_ID.Common.LL.L'Access,
658 Rel_Time, Timedout, Result);
661 Check_Time := Monotonic_Clock;
662 exit when Abs_Time <= Check_Time;
664 Rel_Time := Abs_Time - Check_Time;
667 Self_ID.Common.State := Runnable;
683 procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is
684 pragma Unreferenced (Reason);
686 Cond_Signal (T.Common.LL.CV'Access);
693 procedure Yield (Do_Yield : Boolean := True) is
699 -- If running with Annex-D semantics we need a delay
700 -- above 0 milliseconds here otherwise processes give
701 -- enough time to the other tasks to have a chance to
704 -- This makes cxd8002 ACATS pass on Windows.
714 type Prio_Array_Type is array (System.Any_Priority) of Integer;
715 pragma Atomic_Components (Prio_Array_Type);
717 Prio_Array : Prio_Array_Type;
718 -- Global array containing the id of the currently running task for
721 -- Note: we assume that we are on a single processor with run-til-blocked
724 procedure Set_Priority
726 Prio : System.Any_Priority;
727 Loss_Of_Inheritance : Boolean := False)
730 Array_Item : Integer;
733 Res := SetThreadPriority
734 (T.Common.LL.Thread, Interfaces.C.int (Underlying_Priorities (Prio)));
735 pragma Assert (Res = Win32.TRUE);
737 if Dispatching_Policy = 'F' or else Get_Policy (Prio) = 'F' then
739 -- Annex D requirement [RM D.2.2 par. 9]:
740 -- If the task drops its priority due to the loss of inherited
741 -- priority, it is added at the head of the ready queue for its
742 -- new active priority.
744 if Loss_Of_Inheritance
745 and then Prio < T.Common.Current_Priority
747 Array_Item := Prio_Array (T.Common.Base_Priority) + 1;
748 Prio_Array (T.Common.Base_Priority) := Array_Item;
751 -- Let some processes a chance to arrive
755 -- Then wait for our turn to proceed
757 exit when Array_Item = Prio_Array (T.Common.Base_Priority)
758 or else Prio_Array (T.Common.Base_Priority) = 1;
761 Prio_Array (T.Common.Base_Priority) :=
762 Prio_Array (T.Common.Base_Priority) - 1;
766 T.Common.Current_Priority := Prio;
773 function Get_Priority (T : Task_Id) return System.Any_Priority is
775 return T.Common.Current_Priority;
782 -- There were two paths were we needed to call Enter_Task :
783 -- 1) from System.Task_Primitives.Operations.Initialize
784 -- 2) from System.Tasking.Stages.Task_Wrapper
786 -- The thread initialisation has to be done only for the first case
788 -- This is because the GetCurrentThread NT call does not return the real
789 -- thread handler but only a "pseudo" one. It is not possible to release
790 -- the thread handle and free the system resources from this "pseudo"
791 -- handle. So we really want to keep the real thread handle set in
792 -- System.Task_Primitives.Operations.Create_Task during thread creation.
794 procedure Enter_Task (Self_ID : Task_Id) is
795 procedure Get_Stack_Bounds (Base : Address; Limit : Address);
796 pragma Import (C, Get_Stack_Bounds, "__gnat_get_stack_bounds");
797 -- Get stack boundaries
799 Specific.Set (Self_ID);
801 -- Properly initializes the FPU for x86 systems
803 System.Float_Control.Reset;
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 subtract 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 subtract 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;