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) 1992-2005, 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 2, or (at your option) any later ver- --
14 -- sion. GNARL 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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNARL; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNARL was developed by the GNARL team at Florida State University. --
30 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
32 ------------------------------------------------------------------------------
34 -- This is the VxWorks version of this package
36 -- This package contains all the GNULL primitives that interface directly
37 -- with the underlying OS.
40 -- Turn off polling, we do not want ATC polling to take place during
41 -- tasking operations. It causes infinite loops and other problems.
44 -- used for Ada_Task_Control_Block
46 -- ATCB components and types
48 with System.Tasking.Debug;
49 -- used for Known_Tasks
51 with System.Interrupt_Management;
52 -- used for Keep_Unmasked
55 -- Initialize_Interrupts
57 with System.OS_Interface;
58 -- used for various type, constant, and operations
60 with System.Parameters;
65 with Unchecked_Conversion;
66 with Unchecked_Deallocation;
68 package body System.Task_Primitives.Operations is
70 use System.Tasking.Debug;
72 use System.OS_Interface;
73 use System.Parameters;
74 use type Interfaces.C.int;
76 subtype int is System.OS_Interface.int;
78 Relative : constant := 0;
84 -- The followings are logically constants, but need to be initialized at
87 Single_RTS_Lock : aliased RTS_Lock;
88 -- This is a lock to allow only one thread of control in the RTS at a
89 -- time; it is used to execute in mutual exclusion from all other tasks.
90 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
92 Environment_Task_Id : Task_Id;
93 -- A variable to hold Task_Id for the environment task
95 Unblocked_Signal_Mask : aliased sigset_t;
96 -- The set of signals that should unblocked in all tasks
98 -- The followings are internal configuration constants needed
100 Time_Slice_Val : Integer;
101 pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
103 Locking_Policy : Character;
104 pragma Import (C, Locking_Policy, "__gl_locking_policy");
106 Dispatching_Policy : Character;
107 pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
109 Mutex_Protocol : Priority_Type;
111 Foreign_Task_Elaborated : aliased Boolean := True;
112 -- Used to identified fake tasks (i.e., non-Ada Threads)
120 procedure Initialize;
121 pragma Inline (Initialize);
122 -- Initialize task specific data
124 function Is_Valid_Task return Boolean;
125 pragma Inline (Is_Valid_Task);
126 -- Does executing thread have a TCB?
128 procedure Set (Self_Id : Task_Id);
130 -- Set the self id for the current task
133 pragma Inline (Delete);
134 -- Delete the task specific data associated with the current task
136 function Self return Task_Id;
137 pragma Inline (Self);
138 -- Return a pointer to the Ada Task Control Block of the calling task
142 package body Specific is separate;
143 -- The body of this package is target specific
145 ---------------------------------
146 -- Support for foreign threads --
147 ---------------------------------
149 function Register_Foreign_Thread (Thread : Thread_Id) return Task_Id;
150 -- Allocate and Initialize a new ATCB for the current Thread
152 function Register_Foreign_Thread
153 (Thread : Thread_Id) return Task_Id is separate;
155 -----------------------
156 -- Local Subprograms --
157 -----------------------
159 procedure Abort_Handler (signo : Signal);
160 -- Handler for the abort (SIGABRT) signal to handle asynchronous abort
162 procedure Install_Signal_Handlers;
163 -- Install the default signal handlers for the current task
165 function To_Address is new Unchecked_Conversion (Task_Id, System.Address);
171 procedure Abort_Handler (signo : Signal) is
172 pragma Unreferenced (signo);
174 Self_ID : constant Task_Id := Self;
176 Old_Set : aliased sigset_t;
179 -- It is not safe to raise an exception when using ZCX and the GCC
180 -- exception handling mechanism.
182 if ZCX_By_Default and then GCC_ZCX_Support then
186 if Self_ID.Deferral_Level = 0
187 and then Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
188 and then not Self_ID.Aborting
190 Self_ID.Aborting := True;
192 -- Make sure signals used for RTS internal purpose are unmasked
194 Result := pthread_sigmask (SIG_UNBLOCK,
195 Unblocked_Signal_Mask'Unchecked_Access, Old_Set'Unchecked_Access);
196 pragma Assert (Result = 0);
198 raise Standard'Abort_Signal;
206 procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
207 pragma Unreferenced (T);
208 pragma Unreferenced (On);
211 -- Nothing needed (why not???)
220 function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is
222 return T.Common.LL.Thread;
229 function Self return Task_Id renames Specific.Self;
231 -----------------------------
232 -- Install_Signal_Handlers --
233 -----------------------------
235 procedure Install_Signal_Handlers is
236 act : aliased struct_sigaction;
237 old_act : aliased struct_sigaction;
238 Tmp_Set : aliased sigset_t;
243 act.sa_handler := Abort_Handler'Address;
245 Result := sigemptyset (Tmp_Set'Access);
246 pragma Assert (Result = 0);
247 act.sa_mask := Tmp_Set;
251 (Signal (Interrupt_Management.Abort_Task_Signal),
252 act'Unchecked_Access,
253 old_act'Unchecked_Access);
254 pragma Assert (Result = 0);
256 Interrupt_Management.Initialize_Interrupts;
257 end Install_Signal_Handlers;
259 ---------------------
260 -- Initialize_Lock --
261 ---------------------
263 procedure Initialize_Lock (Prio : System.Any_Priority; L : access Lock) is
265 L.Mutex := semMCreate (SEM_Q_PRIORITY + SEM_INVERSION_SAFE);
266 L.Prio_Ceiling := int (Prio);
267 L.Protocol := Mutex_Protocol;
268 pragma Assert (L.Mutex /= 0);
271 procedure Initialize_Lock (L : access RTS_Lock; Level : Lock_Level) is
272 pragma Unreferenced (Level);
275 L.Mutex := semMCreate (SEM_Q_PRIORITY + SEM_INVERSION_SAFE);
276 L.Prio_Ceiling := int (System.Any_Priority'Last);
277 L.Protocol := Mutex_Protocol;
278 pragma Assert (L.Mutex /= 0);
285 procedure Finalize_Lock (L : access Lock) is
288 Result := semDelete (L.Mutex);
289 pragma Assert (Result = 0);
292 procedure Finalize_Lock (L : access RTS_Lock) is
295 Result := semDelete (L.Mutex);
296 pragma Assert (Result = 0);
303 procedure Write_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
306 if L.Protocol = Prio_Protect
307 and then int (Self.Common.Current_Priority) > L.Prio_Ceiling
309 Ceiling_Violation := True;
312 Ceiling_Violation := False;
315 Result := semTake (L.Mutex, WAIT_FOREVER);
316 pragma Assert (Result = 0);
320 (L : access RTS_Lock;
321 Global_Lock : Boolean := False)
325 if not Single_Lock or else Global_Lock then
326 Result := semTake (L.Mutex, WAIT_FOREVER);
327 pragma Assert (Result = 0);
331 procedure Write_Lock (T : Task_Id) is
334 if not Single_Lock then
335 Result := semTake (T.Common.LL.L.Mutex, WAIT_FOREVER);
336 pragma Assert (Result = 0);
344 procedure Read_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
346 Write_Lock (L, Ceiling_Violation);
353 procedure Unlock (L : access Lock) is
356 Result := semGive (L.Mutex);
357 pragma Assert (Result = 0);
360 procedure Unlock (L : access RTS_Lock; Global_Lock : Boolean := False) is
363 if not Single_Lock or else Global_Lock then
364 Result := semGive (L.Mutex);
365 pragma Assert (Result = 0);
369 procedure Unlock (T : Task_Id) is
372 if not Single_Lock then
373 Result := semGive (T.Common.LL.L.Mutex);
374 pragma Assert (Result = 0);
382 procedure Sleep (Self_ID : Task_Id; Reason : System.Tasking.Task_States) is
383 pragma Unreferenced (Reason);
388 pragma Assert (Self_ID = Self);
390 -- Release the mutex before sleeping
393 Result := semGive (Single_RTS_Lock.Mutex);
395 Result := semGive (Self_ID.Common.LL.L.Mutex);
398 pragma Assert (Result = 0);
400 -- Perform a blocking operation to take the CV semaphore. Note that a
401 -- blocking operation in VxWorks will reenable task scheduling. When we
402 -- are no longer blocked and control is returned, task scheduling will
403 -- again be disabled.
405 Result := semTake (Self_ID.Common.LL.CV, WAIT_FOREVER);
406 pragma Assert (Result = 0);
408 -- Take the mutex back
411 Result := semTake (Single_RTS_Lock.Mutex, WAIT_FOREVER);
413 Result := semTake (Self_ID.Common.LL.L.Mutex, WAIT_FOREVER);
416 pragma Assert (Result = 0);
423 -- This is for use within the run-time system, so abort is assumed to be
424 -- already deferred, and the caller should be holding its own ATCB lock.
426 procedure Timed_Sleep
429 Mode : ST.Delay_Modes;
430 Reason : System.Tasking.Task_States;
431 Timedout : out Boolean;
432 Yielded : out Boolean)
434 pragma Unreferenced (Reason);
436 Orig : constant Duration := Monotonic_Clock;
440 Wakeup : Boolean := False;
446 if Mode = Relative then
447 Absolute := Orig + Time;
449 -- Systematically add one since the first tick will delay *at most*
450 -- 1 / Rate_Duration seconds, so we need to add one to be on the
453 Ticks := To_Clock_Ticks (Time);
455 if Ticks > 0 and then Ticks < int'Last then
461 Ticks := To_Clock_Ticks (Time - Monotonic_Clock);
466 -- Release the mutex before sleeping
469 Result := semGive (Single_RTS_Lock.Mutex);
471 Result := semGive (Self_ID.Common.LL.L.Mutex);
474 pragma Assert (Result = 0);
476 -- Perform a blocking operation to take the CV semaphore. Note
477 -- that a blocking operation in VxWorks will reenable task
478 -- scheduling. When we are no longer blocked and control is
479 -- returned, task scheduling will again be disabled.
481 Result := semTake (Self_ID.Common.LL.CV, Ticks);
485 -- Somebody may have called Wakeup for us
490 if errno /= S_objLib_OBJ_TIMEOUT then
494 -- If Ticks = int'last, it was most probably truncated so
495 -- let's make another round after recomputing Ticks from
496 -- the the absolute time.
498 if Ticks /= int'Last then
501 Ticks := To_Clock_Ticks (Absolute - Monotonic_Clock);
510 -- Take the mutex back
513 Result := semTake (Single_RTS_Lock.Mutex, WAIT_FOREVER);
515 Result := semTake (Self_ID.Common.LL.L.Mutex, WAIT_FOREVER);
518 pragma Assert (Result = 0);
520 exit when Timedout or Wakeup;
526 -- Should never hold a lock while yielding
529 Result := semGive (Single_RTS_Lock.Mutex);
531 Result := semTake (Single_RTS_Lock.Mutex, WAIT_FOREVER);
534 Result := semGive (Self_ID.Common.LL.L.Mutex);
536 Result := semTake (Self_ID.Common.LL.L.Mutex, WAIT_FOREVER);
545 -- This is for use in implementing delay statements, so we assume the
546 -- caller is holding no locks.
548 procedure Timed_Delay
551 Mode : ST.Delay_Modes)
553 Orig : constant Duration := Monotonic_Clock;
558 Aborted : Boolean := False;
561 if Mode = Relative then
562 Absolute := Orig + Time;
563 Ticks := To_Clock_Ticks (Time);
565 if Ticks > 0 and then Ticks < int'Last then
567 -- First tick will delay anytime between 0 and 1 / sysClkRateGet
568 -- seconds, so we need to add one to be on the safe side.
575 Ticks := To_Clock_Ticks (Time - Orig);
580 -- Modifying State and Pending_Priority_Change, locking the TCB
583 Result := semTake (Single_RTS_Lock.Mutex, WAIT_FOREVER);
585 Result := semTake (Self_ID.Common.LL.L.Mutex, WAIT_FOREVER);
588 pragma Assert (Result = 0);
590 Self_ID.Common.State := Delay_Sleep;
594 if Self_ID.Pending_Priority_Change then
595 Self_ID.Pending_Priority_Change := False;
596 Self_ID.Common.Base_Priority := Self_ID.New_Base_Priority;
597 Set_Priority (Self_ID, Self_ID.Common.Base_Priority);
600 Aborted := Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
602 -- Release the TCB before sleeping
605 Result := semGive (Single_RTS_Lock.Mutex);
607 Result := semGive (Self_ID.Common.LL.L.Mutex);
609 pragma Assert (Result = 0);
613 Result := semTake (Self_ID.Common.LL.CV, Ticks);
617 -- If Ticks = int'last, it was most probably truncated
618 -- so let's make another round after recomputing Ticks
619 -- from the the absolute time.
621 if errno = S_objLib_OBJ_TIMEOUT and then Ticks /= int'Last then
624 Ticks := To_Clock_Ticks (Absolute - Monotonic_Clock);
632 -- Take back the lock after having slept, to protect further
633 -- access to Self_ID.
636 Result := semTake (Single_RTS_Lock.Mutex, WAIT_FOREVER);
638 Result := semTake (Self_ID.Common.LL.L.Mutex, WAIT_FOREVER);
641 pragma Assert (Result = 0);
646 Self_ID.Common.State := Runnable;
649 Result := semGive (Single_RTS_Lock.Mutex);
651 Result := semGive (Self_ID.Common.LL.L.Mutex);
659 ---------------------
660 -- Monotonic_Clock --
661 ---------------------
663 function Monotonic_Clock return Duration is
664 TS : aliased timespec;
667 Result := clock_gettime (CLOCK_REALTIME, TS'Unchecked_Access);
668 pragma Assert (Result = 0);
669 return To_Duration (TS);
676 function RT_Resolution return Duration is
678 return 1.0 / Duration (sysClkRateGet);
685 procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is
686 pragma Unreferenced (Reason);
689 Result := semGive (T.Common.LL.CV);
690 pragma Assert (Result = 0);
697 procedure Yield (Do_Yield : Boolean := True) is
698 pragma Unreferenced (Do_Yield);
700 pragma Unreferenced (Result);
702 Result := taskDelay (0);
709 type Prio_Array_Type is array (System.Any_Priority) of Integer;
710 pragma Atomic_Components (Prio_Array_Type);
712 Prio_Array : Prio_Array_Type;
713 -- Global array containing the id of the currently running task for
714 -- each priority. Note that we assume that we are on a single processor
715 -- with run-till-blocked scheduling.
717 procedure Set_Priority
719 Prio : System.Any_Priority;
720 Loss_Of_Inheritance : Boolean := False)
722 Array_Item : Integer;
728 (T.Common.LL.Thread, To_VxWorks_Priority (int (Prio)));
729 pragma Assert (Result = 0);
731 if Dispatching_Policy = 'F' then
733 -- Annex D requirement [RM D.2.2 par. 9]:
735 -- If the task drops its priority due to the loss of inherited
736 -- priority, it is added at the head of the ready queue for its
737 -- new active priority.
739 if Loss_Of_Inheritance
740 and then Prio < T.Common.Current_Priority
742 Array_Item := Prio_Array (T.Common.Base_Priority) + 1;
743 Prio_Array (T.Common.Base_Priority) := Array_Item;
746 -- Give some processes a chance to arrive
750 -- Then wait for our turn to proceed
752 exit when Array_Item = Prio_Array (T.Common.Base_Priority)
753 or else Prio_Array (T.Common.Base_Priority) = 1;
756 Prio_Array (T.Common.Base_Priority) :=
757 Prio_Array (T.Common.Base_Priority) - 1;
761 T.Common.Current_Priority := Prio;
768 function Get_Priority (T : Task_Id) return System.Any_Priority is
770 return T.Common.Current_Priority;
777 procedure Enter_Task (Self_ID : Task_Id) is
778 procedure Init_Float;
779 pragma Import (C, Init_Float, "__gnat_init_float");
780 -- Properly initializes the FPU for PPC/MIPS systems
783 Self_ID.Common.LL.Thread := taskIdSelf;
784 Specific.Set (Self_ID);
788 -- Install the signal handlers
790 -- This is called for each task since there is no signal inheritance
791 -- between VxWorks tasks.
793 Install_Signal_Handlers;
797 for J in Known_Tasks'Range loop
798 if Known_Tasks (J) = null then
799 Known_Tasks (J) := Self_ID;
800 Self_ID.Known_Tasks_Index := J;
812 function New_ATCB (Entry_Num : Task_Entry_Index) return Task_Id is
814 return new Ada_Task_Control_Block (Entry_Num);
821 function Is_Valid_Task return Boolean renames Specific.Is_Valid_Task;
823 -----------------------------
824 -- Register_Foreign_Thread --
825 -----------------------------
827 function Register_Foreign_Thread return Task_Id is
829 if Is_Valid_Task then
832 return Register_Foreign_Thread (taskIdSelf);
834 end Register_Foreign_Thread;
840 procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is
842 Self_ID.Common.LL.CV := semBCreate (SEM_Q_PRIORITY, SEM_EMPTY);
843 Self_ID.Common.LL.Thread := 0;
845 if Self_ID.Common.LL.CV = 0 then
850 if not Single_Lock then
851 Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level);
860 procedure Create_Task
862 Wrapper : System.Address;
863 Stack_Size : System.Parameters.Size_Type;
864 Priority : System.Any_Priority;
865 Succeeded : out Boolean)
867 Adjusted_Stack_Size : size_t;
869 if Stack_Size = Unspecified_Size then
870 Adjusted_Stack_Size := size_t (Default_Stack_Size);
872 elsif Stack_Size < Minimum_Stack_Size then
873 Adjusted_Stack_Size := size_t (Minimum_Stack_Size);
876 Adjusted_Stack_Size := size_t (Stack_Size);
879 -- Ask for four extra bytes of stack space so that the ATCB pointer can
880 -- be stored below the stack limit, plus extra space for the frame of
881 -- Task_Wrapper. This is so the user gets the amount of stack requested
882 -- exclusive of the needs.
884 -- We also have to allocate n more bytes for the task name storage and
885 -- enough space for the Wind Task Control Block which is around 0x778
886 -- bytes. VxWorks also seems to carve out additional space, so use 2048
887 -- as a nice round number. We might want to increment to the nearest
888 -- page size in case we ever support VxVMI.
890 -- ??? - we should come back and visit this so we can set the task name
891 -- to something appropriate.
893 Adjusted_Stack_Size := Adjusted_Stack_Size + 2048;
895 -- Since the initial signal mask of a thread is inherited from the
896 -- creator, and the Environment task has all its signals masked, we do
897 -- not need to manipulate caller's signal mask at this point. All tasks
898 -- in RTS will have All_Tasks_Mask initially.
900 if T.Common.Task_Image_Len = 0 then
901 T.Common.LL.Thread := taskSpawn
902 (System.Null_Address,
903 To_VxWorks_Priority (int (Priority)),
910 Name : aliased String (1 .. T.Common.Task_Image_Len + 1);
913 Name (1 .. Name'Last - 1) :=
914 T.Common.Task_Image (1 .. T.Common.Task_Image_Len);
915 Name (Name'Last) := ASCII.NUL;
917 T.Common.LL.Thread := taskSpawn
919 To_VxWorks_Priority (int (Priority)),
927 if T.Common.LL.Thread = -1 then
933 Task_Creation_Hook (T.Common.LL.Thread);
934 Set_Priority (T, Priority);
941 procedure Finalize_TCB (T : Task_Id) is
944 Is_Self : constant Boolean := (T = Self);
946 procedure Free is new
947 Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id);
950 if not Single_Lock then
951 Result := semDelete (T.Common.LL.L.Mutex);
952 pragma Assert (Result = 0);
955 T.Common.LL.Thread := 0;
957 Result := semDelete (T.Common.LL.CV);
958 pragma Assert (Result = 0);
960 if T.Known_Tasks_Index /= -1 then
961 Known_Tasks (T.Known_Tasks_Index) := null;
975 procedure Exit_Task is
984 procedure Abort_Task (T : Task_Id) is
987 Result := kill (T.Common.LL.Thread,
988 Signal (Interrupt_Management.Abort_Task_Signal));
989 pragma Assert (Result = 0);
996 procedure Initialize (S : in out Suspension_Object) is
998 -- Initialize internal state. It is always initialized to False (ARM
1004 -- Initialize internal mutex
1006 -- Use simpler binary semaphore instead of VxWorks
1007 -- mutual exclusion semaphore, because we don't need
1008 -- the fancier semantics and their overhead.
1010 S.L := semBCreate (SEM_Q_FIFO, SEM_FULL);
1012 -- Initialize internal condition variable
1014 S.CV := semBCreate (SEM_Q_FIFO, SEM_EMPTY);
1021 procedure Finalize (S : in out Suspension_Object) is
1024 -- Destroy internal mutex
1026 Result := semDelete (S.L);
1027 pragma Assert (Result = OK);
1029 -- Destroy internal condition variable
1031 Result := semDelete (S.CV);
1032 pragma Assert (Result = OK);
1039 function Current_State (S : Suspension_Object) return Boolean is
1041 -- We do not want to use lock on this read operation. State is marked
1042 -- as Atomic so that we ensure that the value retrieved is correct.
1051 procedure Set_False (S : in out Suspension_Object) is
1054 Result := semTake (S.L, WAIT_FOREVER);
1055 pragma Assert (Result = OK);
1059 Result := semGive (S.L);
1060 pragma Assert (Result = OK);
1067 procedure Set_True (S : in out Suspension_Object) is
1070 Result := semTake (S.L, WAIT_FOREVER);
1071 pragma Assert (Result = OK);
1073 -- If there is already a task waiting on this suspension object then
1074 -- we resume it, leaving the state of the suspension object to False,
1075 -- as it is specified in ARM D.10 par. 9. Otherwise, it just leaves
1076 -- the state to True.
1082 Result := semGive (S.CV);
1083 pragma Assert (Result = OK);
1088 Result := semGive (S.L);
1089 pragma Assert (Result = OK);
1092 ------------------------
1093 -- Suspend_Until_True --
1094 ------------------------
1096 procedure Suspend_Until_True (S : in out Suspension_Object) is
1099 Result := semTake (S.L, WAIT_FOREVER);
1102 -- Program_Error must be raised upon calling Suspend_Until_True
1103 -- if another task is already waiting on that suspension object
1104 -- (ARM D.10 par. 10).
1106 Result := semGive (S.L);
1107 pragma Assert (Result = OK);
1109 raise Program_Error;
1111 -- Suspend the task if the state is False. Otherwise, the task
1112 -- continues its execution, and the state of the suspension object
1113 -- is set to False (ARM D.10 par. 9).
1118 Result := semGive (S.L);
1119 pragma Assert (Result = 0);
1123 -- Release the mutex before sleeping
1125 Result := semGive (S.L);
1126 pragma Assert (Result = OK);
1128 Result := semTake (S.CV, WAIT_FOREVER);
1129 pragma Assert (Result = 0);
1132 end Suspend_Until_True;
1140 function Check_Exit (Self_ID : ST.Task_Id) return Boolean is
1141 pragma Unreferenced (Self_ID);
1146 --------------------
1147 -- Check_No_Locks --
1148 --------------------
1150 function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is
1151 pragma Unreferenced (Self_ID);
1156 ----------------------
1157 -- Environment_Task --
1158 ----------------------
1160 function Environment_Task return Task_Id is
1162 return Environment_Task_Id;
1163 end Environment_Task;
1169 procedure Lock_RTS is
1171 Write_Lock (Single_RTS_Lock'Access, Global_Lock => True);
1178 procedure Unlock_RTS is
1180 Unlock (Single_RTS_Lock'Access, Global_Lock => True);
1187 function Suspend_Task
1189 Thread_Self : Thread_Id) return Boolean
1192 if T.Common.LL.Thread /= 0
1193 and then T.Common.LL.Thread /= Thread_Self
1195 return taskSuspend (T.Common.LL.Thread) = 0;
1205 function Resume_Task
1207 Thread_Self : Thread_Id) return Boolean
1210 if T.Common.LL.Thread /= 0
1211 and then T.Common.LL.Thread /= Thread_Self
1213 return taskResume (T.Common.LL.Thread) = 0;
1223 procedure Initialize (Environment_Task : Task_Id) is
1226 Environment_Task_Id := Environment_Task;
1228 Interrupt_Management.Initialize;
1229 Specific.Initialize;
1231 if Locking_Policy = 'C' then
1232 Mutex_Protocol := Prio_Protect;
1233 elsif Locking_Policy = 'I' then
1234 Mutex_Protocol := Prio_Inherit;
1236 Mutex_Protocol := Prio_None;
1239 if Time_Slice_Val > 0 then
1240 Result := Set_Time_Slice
1242 (Duration (Time_Slice_Val) / Duration (1_000_000.0)));
1245 Result := sigemptyset (Unblocked_Signal_Mask'Access);
1246 pragma Assert (Result = 0);
1248 for J in Interrupt_Management.Signal_ID loop
1249 if System.Interrupt_Management.Keep_Unmasked (J) then
1250 Result := sigaddset (Unblocked_Signal_Mask'Access, Signal (J));
1251 pragma Assert (Result = 0);
1255 -- Initialize the lock used to synchronize chain of all ATCBs
1257 Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level);
1259 Enter_Task (Environment_Task);
1262 end System.Task_Primitives.Operations;