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 the VxWorks 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_Conversion;
42 with Ada.Unchecked_Deallocation;
46 with System.Tasking.Debug;
47 with System.Interrupt_Management;
49 with System.Soft_Links;
50 -- We use System.Soft_Links instead of System.Tasking.Initialization
51 -- because the later is a higher level package that we shouldn't depend
52 -- on. For example when using the restricted run time, it is replaced by
53 -- System.Tasking.Restricted.Stages.
55 with System.Task_Info;
56 with System.VxWorks.Ext;
58 package body System.Task_Primitives.Operations is
60 package SSL renames System.Soft_Links;
62 use System.Tasking.Debug;
64 use System.OS_Interface;
65 use System.Parameters;
66 use type System.VxWorks.Ext.t_id;
67 use type Interfaces.C.int;
69 subtype int is System.OS_Interface.int;
71 Relative : constant := 0;
77 -- The followings are logically constants, but need to be initialized at
80 Single_RTS_Lock : aliased RTS_Lock;
81 -- This is a lock to allow only one thread of control in the RTS at a
82 -- time; it is used to execute in mutual exclusion from all other tasks.
83 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
85 Environment_Task_Id : Task_Id;
86 -- A variable to hold Task_Id for the environment task
88 Unblocked_Signal_Mask : aliased sigset_t;
89 -- The set of signals that should unblocked in all tasks
91 -- The followings are internal configuration constants needed
93 Time_Slice_Val : Integer;
94 pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
96 Locking_Policy : Character;
97 pragma Import (C, Locking_Policy, "__gl_locking_policy");
99 Dispatching_Policy : Character;
100 pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
102 Mutex_Protocol : Priority_Type;
104 Foreign_Task_Elaborated : aliased Boolean := True;
105 -- Used to identified fake tasks (i.e., non-Ada Threads)
107 type Set_Stack_Limit_Proc_Acc is access procedure;
108 pragma Convention (C, Set_Stack_Limit_Proc_Acc);
110 Set_Stack_Limit_Hook : Set_Stack_Limit_Proc_Acc;
111 pragma Import (C, Set_Stack_Limit_Hook, "__gnat_set_stack_limit_hook");
112 -- Procedure to be called when a task is created to set stack
121 procedure Initialize;
122 pragma Inline (Initialize);
123 -- Initialize task specific data
125 function Is_Valid_Task return Boolean;
126 pragma Inline (Is_Valid_Task);
127 -- Does executing thread have a TCB?
129 procedure Set (Self_Id : Task_Id);
131 -- Set the self id for the current task
134 pragma Inline (Delete);
135 -- Delete the task specific data associated with the current task
137 function Self return Task_Id;
138 pragma Inline (Self);
139 -- Return a pointer to the Ada Task Control Block of the calling task
143 package body Specific is separate;
144 -- The body of this package is target specific
146 ---------------------------------
147 -- Support for foreign threads --
148 ---------------------------------
150 function Register_Foreign_Thread (Thread : Thread_Id) return Task_Id;
151 -- Allocate and Initialize a new ATCB for the current Thread
153 function Register_Foreign_Thread
154 (Thread : Thread_Id) return Task_Id is separate;
156 -----------------------
157 -- Local Subprograms --
158 -----------------------
160 procedure Abort_Handler (signo : Signal);
161 -- Handler for the abort (SIGABRT) signal to handle asynchronous abort
163 procedure Install_Signal_Handlers;
164 -- Install the default signal handlers for the current task
166 function To_Address is
167 new Ada.Unchecked_Conversion (Task_Id, System.Address);
173 procedure Abort_Handler (signo : Signal) is
174 pragma Unreferenced (signo);
176 Self_ID : constant Task_Id := Self;
177 Old_Set : aliased sigset_t;
180 pragma Warnings (Off, Result);
183 -- It is not safe to raise an exception when using ZCX and the GCC
184 -- exception handling mechanism.
186 if ZCX_By_Default and then GCC_ZCX_Support then
190 if Self_ID.Deferral_Level = 0
191 and then Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
192 and then not Self_ID.Aborting
194 Self_ID.Aborting := True;
196 -- Make sure signals used for RTS internal purpose are unmasked
201 Unblocked_Signal_Mask'Access,
203 pragma Assert (Result = 0);
205 raise Standard'Abort_Signal;
213 procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
214 pragma Unreferenced (T);
215 pragma Unreferenced (On);
218 -- Nothing needed (why not???)
227 function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is
229 return T.Common.LL.Thread;
236 function Self return Task_Id renames Specific.Self;
238 -----------------------------
239 -- Install_Signal_Handlers --
240 -----------------------------
242 procedure Install_Signal_Handlers is
243 act : aliased struct_sigaction;
244 old_act : aliased struct_sigaction;
245 Tmp_Set : aliased sigset_t;
250 act.sa_handler := Abort_Handler'Address;
252 Result := sigemptyset (Tmp_Set'Access);
253 pragma Assert (Result = 0);
254 act.sa_mask := Tmp_Set;
258 (Signal (Interrupt_Management.Abort_Task_Interrupt),
259 act'Unchecked_Access,
260 old_act'Unchecked_Access);
261 pragma Assert (Result = 0);
263 Interrupt_Management.Initialize_Interrupts;
264 end Install_Signal_Handlers;
266 ---------------------
267 -- Initialize_Lock --
268 ---------------------
270 procedure Initialize_Lock
271 (Prio : System.Any_Priority;
272 L : not null access Lock)
275 L.Mutex := semMCreate (SEM_Q_PRIORITY + SEM_INVERSION_SAFE);
276 L.Prio_Ceiling := int (Prio);
277 L.Protocol := Mutex_Protocol;
278 pragma Assert (L.Mutex /= 0);
281 procedure Initialize_Lock
282 (L : not null access RTS_Lock;
285 pragma Unreferenced (Level);
287 L.Mutex := semMCreate (SEM_Q_PRIORITY + SEM_INVERSION_SAFE);
288 L.Prio_Ceiling := int (System.Any_Priority'Last);
289 L.Protocol := Mutex_Protocol;
290 pragma Assert (L.Mutex /= 0);
297 procedure Finalize_Lock (L : not null access Lock) is
300 Result := semDelete (L.Mutex);
301 pragma Assert (Result = 0);
304 procedure Finalize_Lock (L : not null access RTS_Lock) is
307 Result := semDelete (L.Mutex);
308 pragma Assert (Result = 0);
316 (L : not null access Lock;
317 Ceiling_Violation : out Boolean)
322 if L.Protocol = Prio_Protect
323 and then int (Self.Common.Current_Priority) > L.Prio_Ceiling
325 Ceiling_Violation := True;
328 Ceiling_Violation := False;
331 Result := semTake (L.Mutex, WAIT_FOREVER);
332 pragma Assert (Result = 0);
336 (L : not null access RTS_Lock;
337 Global_Lock : Boolean := False)
341 if not Single_Lock or else Global_Lock then
342 Result := semTake (L.Mutex, WAIT_FOREVER);
343 pragma Assert (Result = 0);
347 procedure Write_Lock (T : Task_Id) is
350 if not Single_Lock then
351 Result := semTake (T.Common.LL.L.Mutex, WAIT_FOREVER);
352 pragma Assert (Result = 0);
361 (L : not null access Lock;
362 Ceiling_Violation : out Boolean)
365 Write_Lock (L, Ceiling_Violation);
372 procedure Unlock (L : not null access Lock) is
375 Result := semGive (L.Mutex);
376 pragma Assert (Result = 0);
380 (L : not null access RTS_Lock;
381 Global_Lock : Boolean := False)
385 if not Single_Lock or else Global_Lock then
386 Result := semGive (L.Mutex);
387 pragma Assert (Result = 0);
391 procedure Unlock (T : Task_Id) is
394 if not Single_Lock then
395 Result := semGive (T.Common.LL.L.Mutex);
396 pragma Assert (Result = 0);
404 -- Dynamic priority ceilings are not supported by the underlying system
406 procedure Set_Ceiling
407 (L : not null access Lock;
408 Prio : System.Any_Priority)
410 pragma Unreferenced (L, Prio);
419 procedure Sleep (Self_ID : Task_Id; Reason : System.Tasking.Task_States) is
420 pragma Unreferenced (Reason);
425 pragma Assert (Self_ID = Self);
427 -- Release the mutex before sleeping
430 semGive (if Single_Lock
431 then Single_RTS_Lock.Mutex
432 else Self_ID.Common.LL.L.Mutex);
433 pragma Assert (Result = 0);
435 -- Perform a blocking operation to take the CV semaphore. Note that a
436 -- blocking operation in VxWorks will reenable task scheduling. When we
437 -- are no longer blocked and control is returned, task scheduling will
438 -- again be disabled.
440 Result := semTake (Self_ID.Common.LL.CV, WAIT_FOREVER);
441 pragma Assert (Result = 0);
443 -- Take the mutex back
446 semTake ((if Single_Lock
447 then Single_RTS_Lock.Mutex
448 else Self_ID.Common.LL.L.Mutex), WAIT_FOREVER);
449 pragma Assert (Result = 0);
456 -- This is for use within the run-time system, so abort is assumed to be
457 -- already deferred, and the caller should be holding its own ATCB lock.
459 procedure Timed_Sleep
462 Mode : ST.Delay_Modes;
463 Reason : System.Tasking.Task_States;
464 Timedout : out Boolean;
465 Yielded : out Boolean)
467 pragma Unreferenced (Reason);
469 Orig : constant Duration := Monotonic_Clock;
473 Wakeup : Boolean := False;
479 if Mode = Relative then
480 Absolute := Orig + Time;
482 -- Systematically add one since the first tick will delay *at most*
483 -- 1 / Rate_Duration seconds, so we need to add one to be on the
486 Ticks := To_Clock_Ticks (Time);
488 if Ticks > 0 and then Ticks < int'Last then
494 Ticks := To_Clock_Ticks (Time - Monotonic_Clock);
499 -- Release the mutex before sleeping
502 semGive (if Single_Lock
503 then Single_RTS_Lock.Mutex
504 else Self_ID.Common.LL.L.Mutex);
505 pragma Assert (Result = 0);
507 -- Perform a blocking operation to take the CV semaphore. Note
508 -- that a blocking operation in VxWorks will reenable task
509 -- scheduling. When we are no longer blocked and control is
510 -- returned, task scheduling will again be disabled.
512 Result := semTake (Self_ID.Common.LL.CV, Ticks);
516 -- Somebody may have called Wakeup for us
521 if errno /= S_objLib_OBJ_TIMEOUT then
525 -- If Ticks = int'last, it was most probably truncated so
526 -- let's make another round after recomputing Ticks from
527 -- the absolute time.
529 if Ticks /= int'Last then
533 Ticks := To_Clock_Ticks (Absolute - Monotonic_Clock);
542 -- Take the mutex back
545 semTake ((if Single_Lock
546 then Single_RTS_Lock.Mutex
547 else Self_ID.Common.LL.L.Mutex), WAIT_FOREVER);
548 pragma Assert (Result = 0);
550 exit when Timedout or Wakeup;
556 -- Should never hold a lock while yielding
559 Result := semGive (Single_RTS_Lock.Mutex);
561 Result := semTake (Single_RTS_Lock.Mutex, WAIT_FOREVER);
564 Result := semGive (Self_ID.Common.LL.L.Mutex);
566 Result := semTake (Self_ID.Common.LL.L.Mutex, WAIT_FOREVER);
575 -- This is for use in implementing delay statements, so we assume the
576 -- caller is holding no locks.
578 procedure Timed_Delay
581 Mode : ST.Delay_Modes)
583 Orig : constant Duration := Monotonic_Clock;
587 Aborted : Boolean := False;
590 pragma Warnings (Off, Result);
593 if Mode = Relative then
594 Absolute := Orig + Time;
595 Ticks := To_Clock_Ticks (Time);
597 if Ticks > 0 and then Ticks < int'Last then
599 -- First tick will delay anytime between 0 and 1 / sysClkRateGet
600 -- seconds, so we need to add one to be on the safe side.
607 Ticks := To_Clock_Ticks (Time - Orig);
612 -- Modifying State, locking the TCB
615 semTake ((if Single_Lock
616 then Single_RTS_Lock.Mutex
617 else Self_ID.Common.LL.L.Mutex), WAIT_FOREVER);
619 pragma Assert (Result = 0);
621 Self_ID.Common.State := Delay_Sleep;
625 Aborted := Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
627 -- Release the TCB before sleeping
630 semGive (if Single_Lock
631 then Single_RTS_Lock.Mutex
632 else Self_ID.Common.LL.L.Mutex);
633 pragma Assert (Result = 0);
637 Result := semTake (Self_ID.Common.LL.CV, Ticks);
641 -- If Ticks = int'last, it was most probably truncated
642 -- so let's make another round after recomputing Ticks
643 -- from the absolute time.
645 if errno = S_objLib_OBJ_TIMEOUT and then Ticks /= int'Last then
648 Ticks := To_Clock_Ticks (Absolute - Monotonic_Clock);
656 -- Take back the lock after having slept, to protect further
657 -- access to Self_ID.
662 then Single_RTS_Lock.Mutex
663 else Self_ID.Common.LL.L.Mutex), WAIT_FOREVER);
665 pragma Assert (Result = 0);
670 Self_ID.Common.State := Runnable;
675 then Single_RTS_Lock.Mutex
676 else Self_ID.Common.LL.L.Mutex);
683 ---------------------
684 -- Monotonic_Clock --
685 ---------------------
687 function Monotonic_Clock return Duration is
688 TS : aliased timespec;
691 Result := clock_gettime (CLOCK_REALTIME, TS'Unchecked_Access);
692 pragma Assert (Result = 0);
693 return To_Duration (TS);
700 function RT_Resolution return Duration is
702 return 1.0 / Duration (sysClkRateGet);
709 procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is
710 pragma Unreferenced (Reason);
713 Result := semGive (T.Common.LL.CV);
714 pragma Assert (Result = 0);
721 procedure Yield (Do_Yield : Boolean := True) is
722 pragma Unreferenced (Do_Yield);
724 pragma Unreferenced (Result);
726 Result := taskDelay (0);
733 procedure Set_Priority
735 Prio : System.Any_Priority;
736 Loss_Of_Inheritance : Boolean := False)
738 pragma Unreferenced (Loss_Of_Inheritance);
745 (T.Common.LL.Thread, To_VxWorks_Priority (int (Prio)));
746 pragma Assert (Result = 0);
748 -- Note: in VxWorks 6.6 (or earlier), the task is placed at the end of
749 -- the priority queue instead of the head. This is not the behavior
750 -- required by Annex D (RM D.2.3(5/2)), but we consider it an acceptable
751 -- variation (RM 1.1.3(6)), given this is the built-in behavior of the
752 -- operating system. VxWorks versions starting from 6.7 implement the
753 -- required Annex D semantics.
755 -- In older versions we attempted to better approximate the Annex D
756 -- required behavior, but this simulation was not entirely accurate,
757 -- and it seems better to live with the standard VxWorks semantics.
759 T.Common.Current_Priority := Prio;
766 function Get_Priority (T : Task_Id) return System.Any_Priority is
768 return T.Common.Current_Priority;
775 procedure Enter_Task (Self_ID : Task_Id) is
776 procedure Init_Float;
777 pragma Import (C, Init_Float, "__gnat_init_float");
778 -- Properly initializes the FPU for PPC/MIPS systems
781 -- Store the user-level task id in the Thread field (to be used
782 -- internally by the run-time system) and the kernel-level task id in
783 -- the LWP field (to be used by the debugger).
785 Self_ID.Common.LL.Thread := taskIdSelf;
786 Self_ID.Common.LL.LWP := getpid;
788 Specific.Set (Self_ID);
792 -- Install the signal handlers
794 -- This is called for each task since there is no signal inheritance
795 -- between VxWorks tasks.
797 Install_Signal_Handlers;
799 -- If stack checking is enabled, set the stack limit for this task
801 if Set_Stack_Limit_Hook /= null then
802 Set_Stack_Limit_Hook.all;
810 function New_ATCB (Entry_Num : Task_Entry_Index) return Task_Id is
812 return new Ada_Task_Control_Block (Entry_Num);
819 function Is_Valid_Task return Boolean renames Specific.Is_Valid_Task;
821 -----------------------------
822 -- Register_Foreign_Thread --
823 -----------------------------
825 function Register_Foreign_Thread return Task_Id is
827 if Is_Valid_Task then
830 return Register_Foreign_Thread (taskIdSelf);
832 end Register_Foreign_Thread;
838 procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is
840 Self_ID.Common.LL.CV := semBCreate (SEM_Q_PRIORITY, SEM_EMPTY);
841 Self_ID.Common.LL.Thread := 0;
843 if Self_ID.Common.LL.CV = 0 then
849 if not Single_Lock then
850 Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level);
859 procedure Create_Task
861 Wrapper : System.Address;
862 Stack_Size : System.Parameters.Size_Type;
863 Priority : System.Any_Priority;
864 Succeeded : out Boolean)
866 Adjusted_Stack_Size : size_t;
869 use System.Task_Info;
872 -- Ask for four extra bytes of stack space so that the ATCB pointer can
873 -- be stored below the stack limit, plus extra space for the frame of
874 -- Task_Wrapper. This is so the user gets the amount of stack requested
875 -- exclusive of the needs.
877 -- We also have to allocate n more bytes for the task name storage and
878 -- enough space for the Wind Task Control Block which is around 0x778
879 -- bytes. VxWorks also seems to carve out additional space, so use 2048
880 -- as a nice round number. We might want to increment to the nearest
881 -- page size in case we ever support VxVMI.
883 -- ??? - we should come back and visit this so we can set the task name
884 -- to something appropriate.
886 Adjusted_Stack_Size := size_t (Stack_Size) + 2048;
888 -- Since the initial signal mask of a thread is inherited from the
889 -- creator, and the Environment task has all its signals masked, we do
890 -- not need to manipulate caller's signal mask at this point. All tasks
891 -- in RTS will have All_Tasks_Mask initially.
893 -- We now compute the VxWorks task name and options, then spawn ...
896 Name : aliased String (1 .. T.Common.Task_Image_Len + 1);
897 Name_Address : System.Address;
898 -- Task name we are going to hand down to VxWorks
900 function Get_Task_Options return int;
901 pragma Import (C, Get_Task_Options, "__gnat_get_task_options");
902 -- Function that returns the options to be set for the task that we
903 -- are creating. We fetch the options assigned to the current task,
904 -- so offering some user level control over the options for a task
905 -- hierarchy, and force VX_FP_TASK because it is almost always
909 -- If there is no Ada task name handy, let VxWorks choose one.
910 -- Otherwise, tell VxWorks what the Ada task name is.
912 if T.Common.Task_Image_Len = 0 then
913 Name_Address := System.Null_Address;
915 Name (1 .. Name'Last - 1) :=
916 T.Common.Task_Image (1 .. T.Common.Task_Image_Len);
917 Name (Name'Last) := ASCII.NUL;
918 Name_Address := Name'Address;
921 -- Now spawn the VxWorks task for real
923 T.Common.LL.Thread :=
926 To_VxWorks_Priority (int (Priority)),
933 -- Set processor affinity
935 if T.Common.Task_Info /= Unspecified_Task_Info then
937 taskCpuAffinitySet (T.Common.LL.Thread, T.Common.Task_Info);
940 taskDelete (T.Common.LL.Thread);
941 T.Common.LL.Thread := -1;
945 if T.Common.LL.Thread = -1 then
949 Task_Creation_Hook (T.Common.LL.Thread);
950 Set_Priority (T, Priority);
958 procedure Finalize_TCB (T : Task_Id) is
961 Is_Self : constant Boolean := (T = Self);
963 procedure Free is new
964 Ada.Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id);
967 if not Single_Lock then
968 Result := semDelete (T.Common.LL.L.Mutex);
969 pragma Assert (Result = 0);
972 T.Common.LL.Thread := 0;
974 Result := semDelete (T.Common.LL.CV);
975 pragma Assert (Result = 0);
977 if T.Known_Tasks_Index /= -1 then
978 Known_Tasks (T.Known_Tasks_Index) := null;
992 procedure Exit_Task is
1001 procedure Abort_Task (T : Task_Id) is
1006 (T.Common.LL.Thread,
1007 Signal (Interrupt_Management.Abort_Task_Interrupt));
1008 pragma Assert (Result = 0);
1015 procedure Initialize (S : in out Suspension_Object) is
1017 -- Initialize internal state (always to False (RM D.10(6)))
1022 -- Initialize internal mutex
1024 -- Use simpler binary semaphore instead of VxWorks
1025 -- mutual exclusion semaphore, because we don't need
1026 -- the fancier semantics and their overhead.
1028 S.L := semBCreate (SEM_Q_FIFO, SEM_FULL);
1030 -- Initialize internal condition variable
1032 S.CV := semBCreate (SEM_Q_FIFO, SEM_EMPTY);
1039 procedure Finalize (S : in out Suspension_Object) is
1040 pragma Unmodified (S);
1041 -- S may be modified on other targets, but not on VxWorks
1046 -- Destroy internal mutex
1048 Result := semDelete (S.L);
1049 pragma Assert (Result = OK);
1051 -- Destroy internal condition variable
1053 Result := semDelete (S.CV);
1054 pragma Assert (Result = OK);
1061 function Current_State (S : Suspension_Object) return Boolean is
1063 -- We do not want to use lock on this read operation. State is marked
1064 -- as Atomic so that we ensure that the value retrieved is correct.
1073 procedure Set_False (S : in out Suspension_Object) is
1077 SSL.Abort_Defer.all;
1079 Result := semTake (S.L, WAIT_FOREVER);
1080 pragma Assert (Result = OK);
1084 Result := semGive (S.L);
1085 pragma Assert (Result = OK);
1087 SSL.Abort_Undefer.all;
1094 procedure Set_True (S : in out Suspension_Object) is
1098 SSL.Abort_Defer.all;
1100 Result := semTake (S.L, WAIT_FOREVER);
1101 pragma Assert (Result = OK);
1103 -- If there is already a task waiting on this suspension object then
1104 -- we resume it, leaving the state of the suspension object to False,
1105 -- as it is specified in ARM D.10 par. 9. Otherwise, it just leaves
1106 -- the state to True.
1112 Result := semGive (S.CV);
1113 pragma Assert (Result = OK);
1118 Result := semGive (S.L);
1119 pragma Assert (Result = OK);
1121 SSL.Abort_Undefer.all;
1124 ------------------------
1125 -- Suspend_Until_True --
1126 ------------------------
1128 procedure Suspend_Until_True (S : in out Suspension_Object) is
1132 SSL.Abort_Defer.all;
1134 Result := semTake (S.L, WAIT_FOREVER);
1138 -- Program_Error must be raised upon calling Suspend_Until_True
1139 -- if another task is already waiting on that suspension object
1140 -- (ARM D.10 par. 10).
1142 Result := semGive (S.L);
1143 pragma Assert (Result = OK);
1145 SSL.Abort_Undefer.all;
1147 raise Program_Error;
1150 -- Suspend the task if the state is False. Otherwise, the task
1151 -- continues its execution, and the state of the suspension object
1152 -- is set to False (ARM D.10 par. 9).
1157 Result := semGive (S.L);
1158 pragma Assert (Result = 0);
1160 SSL.Abort_Undefer.all;
1165 -- Release the mutex before sleeping
1167 Result := semGive (S.L);
1168 pragma Assert (Result = OK);
1170 SSL.Abort_Undefer.all;
1172 Result := semTake (S.CV, WAIT_FOREVER);
1173 pragma Assert (Result = 0);
1176 end Suspend_Until_True;
1184 function Check_Exit (Self_ID : ST.Task_Id) return Boolean is
1185 pragma Unreferenced (Self_ID);
1190 --------------------
1191 -- Check_No_Locks --
1192 --------------------
1194 function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is
1195 pragma Unreferenced (Self_ID);
1200 ----------------------
1201 -- Environment_Task --
1202 ----------------------
1204 function Environment_Task return Task_Id is
1206 return Environment_Task_Id;
1207 end Environment_Task;
1213 procedure Lock_RTS is
1215 Write_Lock (Single_RTS_Lock'Access, Global_Lock => True);
1222 procedure Unlock_RTS is
1224 Unlock (Single_RTS_Lock'Access, Global_Lock => True);
1231 function Suspend_Task
1233 Thread_Self : Thread_Id) return Boolean
1236 if T.Common.LL.Thread /= 0
1237 and then T.Common.LL.Thread /= Thread_Self
1239 return taskSuspend (T.Common.LL.Thread) = 0;
1249 function Resume_Task
1251 Thread_Self : Thread_Id) return Boolean
1254 if T.Common.LL.Thread /= 0
1255 and then T.Common.LL.Thread /= Thread_Self
1257 return taskResume (T.Common.LL.Thread) = 0;
1263 --------------------
1264 -- Stop_All_Tasks --
1265 --------------------
1267 procedure Stop_All_Tasks
1269 Thread_Self : constant Thread_Id := taskIdSelf;
1273 pragma Unreferenced (Dummy);
1278 C := All_Tasks_List;
1279 while C /= null loop
1280 if C.Common.LL.Thread /= 0
1281 and then C.Common.LL.Thread /= Thread_Self
1283 Dummy := Task_Stop (C.Common.LL.Thread);
1286 C := C.Common.All_Tasks_Link;
1289 Dummy := Int_Unlock;
1296 function Stop_Task (T : ST.Task_Id) return Boolean is
1298 if T.Common.LL.Thread /= 0 then
1299 return Task_Stop (T.Common.LL.Thread) = 0;
1309 function Continue_Task (T : ST.Task_Id) return Boolean
1312 if T.Common.LL.Thread /= 0 then
1313 return Task_Cont (T.Common.LL.Thread) = 0;
1323 procedure Initialize (Environment_Task : Task_Id) is
1327 Environment_Task_Id := Environment_Task;
1329 Interrupt_Management.Initialize;
1330 Specific.Initialize;
1332 if Locking_Policy = 'C' then
1333 Mutex_Protocol := Prio_Protect;
1334 elsif Locking_Policy = 'I' then
1335 Mutex_Protocol := Prio_Inherit;
1337 Mutex_Protocol := Prio_None;
1340 if Time_Slice_Val > 0 then
1344 (Duration (Time_Slice_Val) / Duration (1_000_000.0)));
1346 elsif Dispatching_Policy = 'R' then
1347 Result := Set_Time_Slice (To_Clock_Ticks (0.01));
1351 Result := sigemptyset (Unblocked_Signal_Mask'Access);
1352 pragma Assert (Result = 0);
1354 for J in Interrupt_Management.Signal_ID loop
1355 if System.Interrupt_Management.Keep_Unmasked (J) then
1356 Result := sigaddset (Unblocked_Signal_Mask'Access, Signal (J));
1357 pragma Assert (Result = 0);
1361 -- Initialize the lock used to synchronize chain of all ATCBs
1363 Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level);
1365 -- Make environment task known here because it doesn't go through
1366 -- Activate_Tasks, which does it for all other tasks.
1368 Known_Tasks (Known_Tasks'First) := Environment_Task;
1369 Environment_Task.Known_Tasks_Index := Known_Tasks'First;
1371 Enter_Task (Environment_Task);
1374 end System.Task_Primitives.Operations;