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 Tru64 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.
44 with System.Tasking.Debug;
45 with System.Interrupt_Management;
46 with System.OS_Primitives;
47 with System.Task_Info;
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 on.
52 -- For example when using the restricted run time, it is replaced by
53 -- System.Tasking.Restricted.Stages.
55 package body System.Task_Primitives.Operations is
57 package SSL renames System.Soft_Links;
59 use System.Tasking.Debug;
62 use System.OS_Interface;
63 use System.Parameters;
64 use System.OS_Primitives;
70 -- The followings are logically constants, but need to be initialized
73 Single_RTS_Lock : aliased RTS_Lock;
74 -- This is a lock to allow only one thread of control in the RTS at
75 -- a time; it is used to execute in mutual exclusion from all other tasks.
76 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
78 Environment_Task_Id : Task_Id;
79 -- A variable to hold Task_Id for the environment task
81 Unblocked_Signal_Mask : aliased sigset_t;
82 -- The set of signals that should unblocked in all tasks
84 Time_Slice_Val : Integer;
85 pragma Import (C, Time_Slice_Val, "__gl_time_slice_val");
87 Locking_Policy : Character;
88 pragma Import (C, Locking_Policy, "__gl_locking_policy");
90 Dispatching_Policy : Character;
91 pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
95 Foreign_Task_Elaborated : aliased Boolean := True;
96 -- Used to identified fake tasks (i.e., non-Ada Threads)
98 Abort_Handler_Installed : Boolean := False;
99 -- True if a handler for the abort signal is installed
107 procedure Initialize (Environment_Task : Task_Id);
108 pragma Inline (Initialize);
109 -- Initialize various data needed by this package
111 function Is_Valid_Task return Boolean;
112 pragma Inline (Is_Valid_Task);
113 -- Does executing thread have a TCB?
115 procedure Set (Self_Id : Task_Id);
117 -- Set the self id for the current task
119 function Self return Task_Id;
120 pragma Inline (Self);
121 -- Return a pointer to the Ada Task Control Block of the calling task
125 package body Specific is separate;
126 -- The body of this package is target specific
128 ----------------------------------
129 -- ATCB allocation/deallocation --
130 ----------------------------------
132 package body ATCB_Allocation is separate;
133 -- The body of this package is shared across several targets
135 ---------------------------------
136 -- Support for foreign threads --
137 ---------------------------------
139 function Register_Foreign_Thread (Thread : Thread_Id) return Task_Id;
140 -- Allocate and initialize a new ATCB for the current Thread
142 function Register_Foreign_Thread
143 (Thread : Thread_Id) return Task_Id is separate;
145 -----------------------
146 -- Local Subprograms --
147 -----------------------
149 procedure Abort_Handler (Sig : Signal);
150 -- Signal handler used to implement asynchronous abort
152 function Get_Policy (Prio : System.Any_Priority) return Character;
153 pragma Import (C, Get_Policy, "__gnat_get_specific_dispatching");
154 -- Get priority specific dispatching policy
160 procedure Abort_Handler (Sig : Signal) is
161 pragma Unreferenced (Sig);
163 T : constant Task_Id := Self;
164 Old_Set : aliased sigset_t;
166 Result : Interfaces.C.int;
167 pragma Warnings (Off, Result);
170 -- It's not safe to raise an exception when using GCC ZCX mechanism.
171 -- Note that we still need to install a signal handler, since in some
172 -- cases (e.g. shutdown of the Server_Task in System.Interrupts) we
173 -- need to send the Abort signal to a task.
175 if ZCX_By_Default then
179 if T.Deferral_Level = 0
180 and then T.Pending_ATC_Level < T.ATC_Nesting_Level
181 and then not T.Aborting
185 -- Make sure signals used for RTS internal purpose are unmasked
190 Unblocked_Signal_Mask'Access,
192 pragma Assert (Result = 0);
194 raise Standard'Abort_Signal;
202 -- The underlying thread system sets a guard page at the bottom of a thread
203 -- stack, so nothing is needed.
205 procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
206 pragma Unreferenced (T);
207 pragma Unreferenced (On);
216 function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is
218 return T.Common.LL.Thread;
225 function Self return Task_Id renames Specific.Self;
227 ---------------------
228 -- Initialize_Lock --
229 ---------------------
231 -- Note: mutexes and cond_variables needed per-task basis are initialized
232 -- in Initialize_TCB and the Storage_Error is handled. Other mutexes (such
233 -- as RTS_Lock, Memory_Lock...) used in RTS is initialized before any
234 -- status change of RTS. Therefore raising Storage_Error in the following
235 -- routines should be able to be handled safely.
237 procedure Initialize_Lock
238 (Prio : System.Any_Priority;
239 L : not null access Lock)
241 Attributes : aliased pthread_mutexattr_t;
242 Result : Interfaces.C.int;
245 Result := pthread_mutexattr_init (Attributes'Access);
246 pragma Assert (Result = 0 or else Result = ENOMEM);
248 if Result = ENOMEM then
252 if Locking_Policy = 'C' then
253 L.Ceiling := Interfaces.C.int (Prio);
256 Result := pthread_mutex_init (L.L'Access, Attributes'Access);
257 pragma Assert (Result = 0 or else Result = ENOMEM);
259 if Result = ENOMEM then
260 Result := pthread_mutexattr_destroy (Attributes'Access);
264 Result := pthread_mutexattr_destroy (Attributes'Access);
265 pragma Assert (Result = 0);
268 procedure Initialize_Lock
269 (L : not null access RTS_Lock;
272 pragma Unreferenced (Level);
274 Attributes : aliased pthread_mutexattr_t;
275 Result : Interfaces.C.int;
278 Result := pthread_mutexattr_init (Attributes'Access);
279 pragma Assert (Result = 0 or else Result = ENOMEM);
281 if Result = ENOMEM then
285 Result := pthread_mutex_init (L, Attributes'Access);
286 pragma Assert (Result = 0 or else Result = ENOMEM);
288 if Result = ENOMEM then
289 Result := pthread_mutexattr_destroy (Attributes'Access);
293 Result := pthread_mutexattr_destroy (Attributes'Access);
294 pragma Assert (Result = 0);
301 procedure Finalize_Lock (L : not null access Lock) is
302 Result : Interfaces.C.int;
304 Result := pthread_mutex_destroy (L.L'Access);
305 pragma Assert (Result = 0);
308 procedure Finalize_Lock (L : not null access RTS_Lock) is
309 Result : Interfaces.C.int;
311 Result := pthread_mutex_destroy (L);
312 pragma Assert (Result = 0);
320 (L : not null access Lock;
321 Ceiling_Violation : out Boolean)
323 Result : Interfaces.C.int;
325 All_Tasks_Link : Task_Id;
326 Current_Prio : System.Any_Priority;
329 -- Perform ceiling checks only when this is the locking policy in use
331 if Locking_Policy = 'C' then
333 All_Tasks_Link := Self_ID.Common.All_Tasks_Link;
334 Current_Prio := Get_Priority (Self_ID);
336 -- If there is no other task, no need to check priorities
338 if All_Tasks_Link /= Null_Task
339 and then L.Ceiling < Interfaces.C.int (Current_Prio)
341 Ceiling_Violation := True;
346 Result := pthread_mutex_lock (L.L'Access);
347 pragma Assert (Result = 0);
349 Ceiling_Violation := False;
353 (L : not null access RTS_Lock;
354 Global_Lock : Boolean := False)
356 Result : Interfaces.C.int;
358 if not Single_Lock or else Global_Lock then
359 Result := pthread_mutex_lock (L);
360 pragma Assert (Result = 0);
364 procedure Write_Lock (T : Task_Id) is
365 Result : Interfaces.C.int;
367 if not Single_Lock then
368 Result := pthread_mutex_lock (T.Common.LL.L'Access);
369 pragma Assert (Result = 0);
378 (L : not null access Lock;
379 Ceiling_Violation : out Boolean)
382 Write_Lock (L, Ceiling_Violation);
389 procedure Unlock (L : not null access Lock) is
390 Result : Interfaces.C.int;
392 Result := pthread_mutex_unlock (L.L'Access);
393 pragma Assert (Result = 0);
397 (L : not null access RTS_Lock;
398 Global_Lock : Boolean := False)
400 Result : Interfaces.C.int;
402 if not Single_Lock or else Global_Lock then
403 Result := pthread_mutex_unlock (L);
404 pragma Assert (Result = 0);
408 procedure Unlock (T : Task_Id) is
409 Result : Interfaces.C.int;
411 if not Single_Lock then
412 Result := pthread_mutex_unlock (T.Common.LL.L'Access);
413 pragma Assert (Result = 0);
421 -- Dynamic priority ceilings are not supported by the underlying system
423 procedure Set_Ceiling
424 (L : not null access Lock;
425 Prio : System.Any_Priority)
427 pragma Unreferenced (L, Prio);
438 Reason : System.Tasking.Task_States)
440 pragma Unreferenced (Reason);
442 Result : Interfaces.C.int;
447 (cond => Self_ID.Common.LL.CV'Access,
448 mutex => (if Single_Lock
449 then Single_RTS_Lock'Access
450 else Self_ID.Common.LL.L'Access));
452 -- EINTR is not considered a failure
454 pragma Assert (Result = 0 or else Result = EINTR);
461 -- This is for use within the run-time system, so abort is assumed to be
462 -- already deferred, and the caller should be holding its own ATCB lock.
464 procedure Timed_Sleep
467 Mode : ST.Delay_Modes;
468 Reason : System.Tasking.Task_States;
469 Timedout : out Boolean;
470 Yielded : out Boolean)
472 pragma Unreferenced (Reason);
474 Base_Time : constant Duration := Monotonic_Clock;
475 Check_Time : Duration := Base_Time;
477 Request : aliased timespec;
478 Result : Interfaces.C.int;
486 then Duration'Min (Time, Max_Sensible_Delay) + Check_Time
487 else Duration'Min (Check_Time + Max_Sensible_Delay, Time));
489 if Abs_Time > Check_Time then
490 Request := To_Timespec (Abs_Time);
493 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
496 pthread_cond_timedwait
497 (cond => Self_ID.Common.LL.CV'Access,
498 mutex => (if Single_Lock
499 then Single_RTS_Lock'Access
500 else Self_ID.Common.LL.L'Access),
501 abstime => Request'Access);
503 Check_Time := Monotonic_Clock;
504 exit when Abs_Time <= Check_Time or else Check_Time < Base_Time;
506 if Result = 0 or Result = EINTR then
508 -- Somebody may have called Wakeup for us
514 pragma Assert (Result = ETIMEDOUT);
523 -- This is for use in implementing delay statements, so we assume the
524 -- caller is abort-deferred but is holding no locks.
526 procedure Timed_Delay
529 Mode : ST.Delay_Modes)
531 Base_Time : constant Duration := Monotonic_Clock;
532 Check_Time : Duration := Base_Time;
534 Request : aliased timespec;
535 Result : Interfaces.C.int;
542 Write_Lock (Self_ID);
546 then Time + Check_Time
547 else Duration'Min (Check_Time + Max_Sensible_Delay, Time));
549 if Abs_Time > Check_Time then
550 Request := To_Timespec (Abs_Time);
551 Self_ID.Common.State := Delay_Sleep;
554 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
557 pthread_cond_timedwait
558 (cond => Self_ID.Common.LL.CV'Access,
559 mutex => (if Single_Lock
560 then Single_RTS_Lock'Access
561 else Self_ID.Common.LL.L'Access),
562 abstime => Request'Access);
564 Check_Time := Monotonic_Clock;
565 exit when Abs_Time <= Check_Time or else Check_Time < Base_Time;
567 pragma Assert (Result = 0 or else
568 Result = ETIMEDOUT or else
572 Self_ID.Common.State := Runnable;
584 ---------------------
585 -- Monotonic_Clock --
586 ---------------------
588 function Monotonic_Clock return Duration is
589 TS : aliased timespec;
590 Result : Interfaces.C.int;
592 Result := clock_gettime (CLOCK_REALTIME, TS'Unchecked_Access);
593 pragma Assert (Result = 0);
594 return To_Duration (TS);
601 function RT_Resolution return Duration is
603 -- Returned value must be an integral multiple of Duration'Small (1 ns)
604 -- The following is the best approximation of 1/1024. The clock on the
605 -- DEC Alpha ticks at 1024 Hz.
607 return 0.000_976_563;
614 procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is
615 pragma Unreferenced (Reason);
616 Result : Interfaces.C.int;
618 Result := pthread_cond_signal (T.Common.LL.CV'Access);
619 pragma Assert (Result = 0);
626 procedure Yield (Do_Yield : Boolean := True) is
627 Result : Interfaces.C.int;
628 pragma Unreferenced (Result);
631 Result := sched_yield;
639 procedure Set_Priority
641 Prio : System.Any_Priority;
642 Loss_Of_Inheritance : Boolean := False)
644 pragma Unreferenced (Loss_Of_Inheritance);
646 Result : Interfaces.C.int;
647 Param : aliased struct_sched_param;
649 Priority_Specific_Policy : constant Character := Get_Policy (Prio);
650 -- Upper case first character of the policy name corresponding to the
651 -- task as set by a Priority_Specific_Dispatching pragma.
654 T.Common.Current_Priority := Prio;
655 Param.sched_priority := Interfaces.C.int (Underlying_Priorities (Prio));
657 if Dispatching_Policy = 'R'
658 or else Priority_Specific_Policy = 'R'
659 or else Time_Slice_Val > 0
662 pthread_setschedparam
663 (T.Common.LL.Thread, SCHED_RR, Param'Access);
665 elsif Dispatching_Policy = 'F'
666 or else Priority_Specific_Policy = 'F'
667 or else Time_Slice_Val = 0
670 pthread_setschedparam
671 (T.Common.LL.Thread, SCHED_FIFO, Param'Access);
675 pthread_setschedparam
676 (T.Common.LL.Thread, SCHED_OTHER, Param'Access);
679 pragma Assert (Result = 0);
686 function Get_Priority (T : Task_Id) return System.Any_Priority is
688 return T.Common.Current_Priority;
695 procedure Enter_Task (Self_ID : Task_Id) is
697 Hide_Unhide_Yellow_Zone (Hide => True);
698 Self_ID.Common.LL.Thread := pthread_self;
700 Specific.Set (Self_ID);
707 function Is_Valid_Task return Boolean renames Specific.Is_Valid_Task;
709 -----------------------------
710 -- Register_Foreign_Thread --
711 -----------------------------
713 function Register_Foreign_Thread return Task_Id is
715 if Is_Valid_Task then
718 return Register_Foreign_Thread (pthread_self);
720 end Register_Foreign_Thread;
726 procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is
727 Mutex_Attr : aliased pthread_mutexattr_t;
728 Result : Interfaces.C.int;
729 Cond_Attr : aliased pthread_condattr_t;
732 if not Single_Lock then
733 Result := pthread_mutexattr_init (Mutex_Attr'Access);
734 pragma Assert (Result = 0 or else Result = ENOMEM);
739 (Self_ID.Common.LL.L'Access, Mutex_Attr'Access);
740 pragma Assert (Result = 0 or else Result = ENOMEM);
748 Result := pthread_mutexattr_destroy (Mutex_Attr'Access);
749 pragma Assert (Result = 0);
752 Result := pthread_condattr_init (Cond_Attr'Access);
753 pragma Assert (Result = 0 or else Result = ENOMEM);
758 (Self_ID.Common.LL.CV'Access, Cond_Attr'Access);
759 pragma Assert (Result = 0 or else Result = ENOMEM);
765 if not Single_Lock then
766 Result := pthread_mutex_destroy (Self_ID.Common.LL.L'Access);
767 pragma Assert (Result = 0);
773 Result := pthread_condattr_destroy (Cond_Attr'Access);
774 pragma Assert (Result = 0);
781 procedure Create_Task
783 Wrapper : System.Address;
784 Stack_Size : System.Parameters.Size_Type;
785 Priority : System.Any_Priority;
786 Succeeded : out Boolean)
788 Attributes : aliased pthread_attr_t;
789 Adjusted_Stack_Size : Interfaces.C.size_t;
790 Result : Interfaces.C.int;
791 Param : aliased System.OS_Interface.struct_sched_param;
793 Priority_Specific_Policy : constant Character := Get_Policy (Priority);
794 -- Upper case first character of the policy name corresponding to the
795 -- task as set by a Priority_Specific_Dispatching pragma.
797 use System.Task_Info;
800 -- Account for the Yellow Zone (2 pages) and the guard page right above.
801 -- See Hide_Unhide_Yellow_Zone for the rationale.
803 Adjusted_Stack_Size :=
804 Interfaces.C.size_t (Stack_Size) + 3 * Get_Page_Size;
806 Result := pthread_attr_init (Attributes'Access);
807 pragma Assert (Result = 0 or else Result = ENOMEM);
815 pthread_attr_setdetachstate
816 (Attributes'Access, PTHREAD_CREATE_DETACHED);
817 pragma Assert (Result = 0);
820 pthread_attr_setstacksize
821 (Attributes'Access, Adjusted_Stack_Size);
822 pragma Assert (Result = 0);
824 Param.sched_priority :=
825 Interfaces.C.int (Underlying_Priorities (Priority));
827 pthread_attr_setschedparam
828 (Attributes'Access, Param'Access);
829 pragma Assert (Result = 0);
831 if Dispatching_Policy = 'R'
832 or else Priority_Specific_Policy = 'R'
833 or else Time_Slice_Val > 0
836 pthread_attr_setschedpolicy
837 (Attributes'Access, System.OS_Interface.SCHED_RR);
839 elsif Dispatching_Policy = 'F'
840 or else Priority_Specific_Policy = 'F'
841 or else Time_Slice_Val = 0
844 pthread_attr_setschedpolicy
845 (Attributes'Access, System.OS_Interface.SCHED_FIFO);
849 pthread_attr_setschedpolicy
850 (Attributes'Access, System.OS_Interface.SCHED_OTHER);
853 pragma Assert (Result = 0);
855 -- Set the scheduling parameters explicitly, since this is the only way
856 -- to force the OS to take e.g. the sched policy and scope attributes
860 pthread_attr_setinheritsched
861 (Attributes'Access, PTHREAD_EXPLICIT_SCHED);
862 pragma Assert (Result = 0);
864 T.Common.Current_Priority := Priority;
866 if T.Common.Task_Info /= null then
867 case T.Common.Task_Info.Contention_Scope is
868 when System.Task_Info.Process_Scope =>
870 pthread_attr_setscope
871 (Attributes'Access, PTHREAD_SCOPE_PROCESS);
873 when System.Task_Info.System_Scope =>
875 pthread_attr_setscope
876 (Attributes'Access, PTHREAD_SCOPE_SYSTEM);
878 when System.Task_Info.Default_Scope =>
882 pragma Assert (Result = 0);
885 -- Since the initial signal mask of a thread is inherited from the
886 -- creator, and the Environment task has all its signals masked, we
887 -- do not need to manipulate caller's signal mask at this point.
888 -- All tasks in RTS will have All_Tasks_Mask initially.
892 (T.Common.LL.Thread'Access,
894 Thread_Body_Access (Wrapper),
896 pragma Assert (Result = 0 or else Result = EAGAIN);
898 Succeeded := Result = 0;
900 Result := pthread_attr_destroy (Attributes'Access);
901 pragma Assert (Result = 0);
903 if Succeeded and then T.Common.Task_Info /= null then
905 -- ??? We're using a process-wide function to implement a task
906 -- specific characteristic.
908 if T.Common.Task_Info.Bind_To_Cpu_Number = 0 then
909 Result := bind_to_cpu (Curpid, 0);
911 elsif T.Common.Task_Info.Bind_To_Cpu_Number > 0 then
915 Interfaces.C.unsigned_long (
916 Interfaces.Shift_Left
917 (Interfaces.Unsigned_64'(1),
918 T.Common.Task_Info.Bind_To_Cpu_Number - 1)));
919 pragma Assert (Result = 0);
928 procedure Finalize_TCB (T : Task_Id) is
929 Result : Interfaces.C.int;
932 if not Single_Lock then
933 Result := pthread_mutex_destroy (T.Common.LL.L'Access);
934 pragma Assert (Result = 0);
937 Result := pthread_cond_destroy (T.Common.LL.CV'Access);
938 pragma Assert (Result = 0);
940 if T.Known_Tasks_Index /= -1 then
941 Known_Tasks (T.Known_Tasks_Index) := null;
944 ATCB_Allocation.Free_ATCB (T);
951 procedure Exit_Task is
954 Hide_Unhide_Yellow_Zone (Hide => False);
961 procedure Abort_Task (T : Task_Id) is
962 Result : Interfaces.C.int;
964 if Abort_Handler_Installed then
965 Result := pthread_kill (T.Common.LL.Thread,
966 Signal (System.Interrupt_Management.Abort_Task_Interrupt));
967 pragma Assert (Result = 0);
975 procedure Initialize (S : in out Suspension_Object) is
976 Mutex_Attr : aliased pthread_mutexattr_t;
977 Cond_Attr : aliased pthread_condattr_t;
978 Result : Interfaces.C.int;
981 -- Initialize internal state (always to False (RM D.10(6)))
986 -- Initialize internal mutex
988 Result := pthread_mutexattr_init (Mutex_Attr'Access);
989 pragma Assert (Result = 0 or else Result = ENOMEM);
991 if Result = ENOMEM then
995 Result := pthread_mutex_init (S.L'Access, Mutex_Attr'Access);
996 pragma Assert (Result = 0 or else Result = ENOMEM);
998 if Result = ENOMEM then
999 Result := pthread_mutexattr_destroy (Mutex_Attr'Access);
1000 raise Storage_Error;
1003 Result := pthread_mutexattr_destroy (Mutex_Attr'Access);
1004 pragma Assert (Result = 0);
1006 -- Initialize internal condition variable
1008 Result := pthread_condattr_init (Cond_Attr'Access);
1009 pragma Assert (Result = 0 or else Result = ENOMEM);
1011 Result := pthread_cond_init (S.CV'Access, Cond_Attr'Access);
1013 pragma Assert (Result = 0 or else Result = ENOMEM);
1016 Result := pthread_mutex_destroy (S.L'Access);
1017 pragma Assert (Result = 0);
1019 if Result = ENOMEM then
1020 raise Storage_Error;
1029 procedure Finalize (S : in out Suspension_Object) is
1030 Result : Interfaces.C.int;
1033 -- Destroy internal mutex
1035 Result := pthread_mutex_destroy (S.L'Access);
1036 pragma Assert (Result = 0);
1038 -- Destroy internal condition variable
1040 Result := pthread_cond_destroy (S.CV'Access);
1041 pragma Assert (Result = 0);
1048 function Current_State (S : Suspension_Object) return Boolean is
1050 -- We do not want to use lock on this read operation. State is marked
1051 -- as Atomic so that we ensure that the value retrieved is correct.
1060 procedure Set_False (S : in out Suspension_Object) is
1061 Result : Interfaces.C.int;
1064 SSL.Abort_Defer.all;
1066 Result := pthread_mutex_lock (S.L'Access);
1067 pragma Assert (Result = 0);
1071 Result := pthread_mutex_unlock (S.L'Access);
1072 pragma Assert (Result = 0);
1074 SSL.Abort_Undefer.all;
1081 procedure Set_True (S : in out Suspension_Object) is
1082 Result : Interfaces.C.int;
1085 SSL.Abort_Defer.all;
1087 Result := pthread_mutex_lock (S.L'Access);
1088 pragma Assert (Result = 0);
1090 -- If there is already a task waiting on this suspension object then we
1091 -- resume it, leaving the state of the suspension object to False, as
1092 -- specified in (RM D.10(9)). Otherwise, leave the state set to True.
1098 Result := pthread_cond_signal (S.CV'Access);
1099 pragma Assert (Result = 0);
1105 Result := pthread_mutex_unlock (S.L'Access);
1106 pragma Assert (Result = 0);
1108 SSL.Abort_Undefer.all;
1111 ------------------------
1112 -- Suspend_Until_True --
1113 ------------------------
1115 procedure Suspend_Until_True (S : in out Suspension_Object) is
1116 Result : Interfaces.C.int;
1119 SSL.Abort_Defer.all;
1121 Result := pthread_mutex_lock (S.L'Access);
1122 pragma Assert (Result = 0);
1126 -- Program_Error must be raised upon calling Suspend_Until_True
1127 -- if another task is already waiting on that suspension object
1130 Result := pthread_mutex_unlock (S.L'Access);
1131 pragma Assert (Result = 0);
1133 SSL.Abort_Undefer.all;
1135 raise Program_Error;
1138 -- Suspend the task if the state is False. Otherwise, the task
1139 -- continues its execution, and the state of the suspension object
1140 -- is set to False (RM D.10(9)).
1148 -- Loop in case pthread_cond_wait returns earlier than expected
1149 -- (e.g. in case of EINTR caused by a signal).
1151 Result := pthread_cond_wait (S.CV'Access, S.L'Access);
1152 pragma Assert (Result = 0 or else Result = EINTR);
1154 exit when not S.Waiting;
1158 Result := pthread_mutex_unlock (S.L'Access);
1159 pragma Assert (Result = 0);
1161 SSL.Abort_Undefer.all;
1163 end Suspend_Until_True;
1171 function Check_Exit (Self_ID : ST.Task_Id) return Boolean is
1172 pragma Unreferenced (Self_ID);
1177 --------------------
1178 -- Check_No_Locks --
1179 --------------------
1181 function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is
1182 pragma Unreferenced (Self_ID);
1187 ----------------------
1188 -- Environment_Task --
1189 ----------------------
1191 function Environment_Task return Task_Id is
1193 return Environment_Task_Id;
1194 end Environment_Task;
1200 procedure Lock_RTS is
1202 Write_Lock (Single_RTS_Lock'Access, Global_Lock => True);
1209 procedure Unlock_RTS is
1211 Unlock (Single_RTS_Lock'Access, Global_Lock => True);
1218 function Suspend_Task
1220 Thread_Self : Thread_Id) return Boolean
1222 pragma Unreferenced (T, Thread_Self);
1231 function Resume_Task
1233 Thread_Self : Thread_Id) return Boolean
1235 pragma Unreferenced (T, Thread_Self);
1240 --------------------
1241 -- Stop_All_Tasks --
1242 --------------------
1244 procedure Stop_All_Tasks is
1253 function Stop_Task (T : ST.Task_Id) return Boolean is
1254 pragma Unreferenced (T);
1263 function Continue_Task (T : ST.Task_Id) return Boolean is
1264 pragma Unreferenced (T);
1273 procedure Initialize (Environment_Task : Task_Id) is
1274 act : aliased struct_sigaction;
1275 old_act : aliased struct_sigaction;
1276 Tmp_Set : aliased sigset_t;
1277 Result : Interfaces.C.int;
1280 (Int : System.Interrupt_Management.Interrupt_ID) return Character;
1281 pragma Import (C, State, "__gnat_get_interrupt_state");
1282 -- Get interrupt state. Defined in a-init.c. The input argument is
1283 -- the interrupt number, and the result is one of the following:
1285 Default : constant Character := 's';
1286 -- 'n' this interrupt not set by any Interrupt_State pragma
1287 -- 'u' Interrupt_State pragma set state to User
1288 -- 'r' Interrupt_State pragma set state to Runtime
1289 -- 's' Interrupt_State pragma set state to System (use "default"
1293 Environment_Task_Id := Environment_Task;
1295 Interrupt_Management.Initialize;
1297 -- Prepare the set of signals that should unblocked in all tasks
1299 Result := sigemptyset (Unblocked_Signal_Mask'Access);
1300 pragma Assert (Result = 0);
1302 for J in Interrupt_Management.Interrupt_ID loop
1303 if System.Interrupt_Management.Keep_Unmasked (J) then
1304 Result := sigaddset (Unblocked_Signal_Mask'Access, Signal (J));
1305 pragma Assert (Result = 0);
1311 -- Initialize the lock used to synchronize chain of all ATCBs
1313 Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level);
1315 Specific.Initialize (Environment_Task);
1317 -- Make environment task known here because it doesn't go through
1318 -- Activate_Tasks, which does it for all other tasks.
1320 Known_Tasks (Known_Tasks'First) := Environment_Task;
1321 Environment_Task.Known_Tasks_Index := Known_Tasks'First;
1323 Enter_Task (Environment_Task);
1326 (System.Interrupt_Management.Abort_Task_Interrupt) /= Default
1329 act.sa_handler := Abort_Handler'Address;
1331 Result := sigemptyset (Tmp_Set'Access);
1332 pragma Assert (Result = 0);
1333 act.sa_mask := Tmp_Set;
1337 (Signal (System.Interrupt_Management.Abort_Task_Interrupt),
1338 act'Unchecked_Access,
1339 old_act'Unchecked_Access);
1340 pragma Assert (Result = 0);
1341 Abort_Handler_Installed := True;
1345 -----------------------
1346 -- Set_Task_Affinity --
1347 -----------------------
1349 procedure Set_Task_Affinity (T : ST.Task_Id) is
1350 pragma Unreferenced (T);
1353 -- Setting task affinity is not supported by the underlying system
1356 end Set_Task_Affinity;
1357 end System.Task_Primitives.Operations;