1 ------------------------------------------------------------------------------
3 -- GNU ADA 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) 1992-2004, 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, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, 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 an Irix (old athread library) 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.
47 with System.Tasking.Debug;
48 -- used for Known_Tasks
50 with System.Task_Info;
52 with System.Interrupt_Management;
53 -- used for Keep_Unmasked
54 -- Abort_Task_Interrupt
57 with System.Parameters;
61 -- used for Ada_Task_Control_Block
64 with System.Program_Info;
65 -- used for Default_Task_Stack
68 -- Pthread_Sched_Signal
71 with System.Soft_Links;
72 -- used for Defer/Undefer_Abort
74 -- Note that we do not use System.Tasking.Initialization directly since
75 -- this is a higher level package that we shouldn't depend on. For example
76 -- when using the restricted run time, it is replaced by
77 -- System.Tasking.Restricted.Stages.
79 with System.OS_Primitives;
80 -- used for Delay_Modes
82 with System.Storage_Elements;
83 -- used for To_Address
85 with Unchecked_Conversion;
86 with Unchecked_Deallocation;
88 package body System.Task_Primitives.Operations is
90 use System.Tasking.Debug;
93 use System.OS_Interface;
94 use System.Parameters;
95 use System.OS_Primitives;
97 package SSL renames System.Soft_Links;
103 -- The followings are logically constants, but need to be initialized
106 Single_RTS_Lock : aliased RTS_Lock;
107 -- This is a lock to allow only one thread of control in the RTS at
108 -- a time; it is used to execute in mutual exclusion from all other tasks.
109 -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List
111 Environment_Task_Id : Task_Id;
112 -- A variable to hold Task_Id for the environment task.
114 Locking_Policy : Character;
115 pragma Import (C, Locking_Policy, "__gl_locking_policy");
117 Clock_Address : constant System.Address :=
118 System.Storage_Elements.To_Address (16#200F90#);
120 RT_Clock_Id : clockid_t;
121 for RT_Clock_Id'Address use Clock_Address;
123 -----------------------
124 -- Local Subprograms --
125 -----------------------
127 procedure Initialize_Athread_Library;
129 function To_Task_Id is new Unchecked_Conversion (System.Address, Task_Id);
130 function To_Address is new Unchecked_Conversion (Task_Id, System.Address);
136 -- The underlying thread system sets a guard page at the
137 -- bottom of a thread stack, so nothing is needed.
138 -- ??? Check the comment above
140 procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
141 pragma Unreferenced (T);
142 pragma Unreferenced (On);
151 function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is
153 return T.Common.LL.Thread;
160 function Self return Task_Id is
162 return To_Task_Id (pthread_get_current_ada_tcb);
165 ---------------------
166 -- Initialize_Lock --
167 ---------------------
169 -- Note: mutexes and cond_variables needed per-task basis are
170 -- initialized in Initialize_TCB and the Storage_Error is
171 -- handled. Other mutexes (such as RTS_Lock, Memory_Lock...)
172 -- used in RTS is initialized before any status change of RTS.
173 -- Therefore rasing Storage_Error in the following routines
174 -- should be able to be handled safely.
176 procedure Initialize_Lock
177 (Prio : System.Any_Priority;
180 Attributes : aliased pthread_mutexattr_t;
181 Result : Interfaces.C.int;
184 Result := pthread_mutexattr_init (Attributes'Access);
186 if Result = FUNC_ERR then
190 if Locking_Policy = 'C' then
192 Result := pthread_mutexattr_setqueueorder
193 (Attributes'Access, MUTEX_PRIORITY_CEILING);
195 pragma Assert (Result /= FUNC_ERR);
197 Result := pthread_mutexattr_setceilingprio
198 (Attributes'Access, Interfaces.C.int (Prio));
200 pragma Assert (Result /= FUNC_ERR);
203 Result := pthread_mutex_init (L, Attributes'Access);
205 if Result = FUNC_ERR then
206 Result := pthread_mutexattr_destroy (Attributes'Access);
210 Result := pthread_mutexattr_destroy (Attributes'Access);
213 procedure Initialize_Lock (L : access RTS_Lock; Level : Lock_Level) is
214 pragma Unreferenced (Level);
216 Attributes : aliased pthread_mutexattr_t;
217 Result : Interfaces.C.int;
220 Result := pthread_mutexattr_init (Attributes'Access);
222 if Result = FUNC_ERR then
226 if Locking_Policy = 'C' then
227 Result := pthread_mutexattr_setqueueorder
228 (Attributes'Access, MUTEX_PRIORITY_CEILING);
229 pragma Assert (Result /= FUNC_ERR);
231 Result := pthread_mutexattr_setceilingprio
232 (Attributes'Access, Interfaces.C.int (System.Any_Priority'Last));
233 pragma Assert (Result /= FUNC_ERR);
236 Result := pthread_mutex_init (L, Attributes'Access);
238 if Result = FUNC_ERR then
239 Result := pthread_mutexattr_destroy (Attributes'Access);
243 Result := pthread_mutexattr_destroy (Attributes'Access);
250 procedure Finalize_Lock (L : access Lock) is
251 Result : Interfaces.C.int;
253 Result := pthread_mutex_destroy (L);
254 pragma Assert (Result = 0);
257 procedure Finalize_Lock (L : access RTS_Lock) is
258 Result : Interfaces.C.int;
260 Result := pthread_mutex_destroy (L);
261 pragma Assert (Result = 0);
268 procedure Write_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
269 Result : Interfaces.C.int;
271 Result := pthread_mutex_lock (L);
272 Ceiling_Violation := Result = FUNC_ERR and then errno = EINVAL;
273 pragma Assert (Result /= FUNC_ERR);
277 (L : access RTS_Lock; Global_Lock : Boolean := False)
279 Result : Interfaces.C.int;
281 if not Single_Lock or else Global_Lock then
282 Result := pthread_mutex_lock (L);
283 pragma Assert (Result = 0);
287 procedure Write_Lock (T : Task_Id) is
288 Result : Interfaces.C.int;
290 if not Single_Lock then
291 Result := pthread_mutex_lock (T.Common.LL.L'Access);
292 pragma Assert (Result = 0);
300 procedure Read_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
302 Write_Lock (L, Ceiling_Violation);
309 procedure Unlock (L : access Lock) is
310 Result : Interfaces.C.int;
312 Result := pthread_mutex_unlock (L);
313 pragma Assert (Result = 0);
316 procedure Unlock (L : access RTS_Lock; Global_Lock : Boolean := False) is
317 Result : Interfaces.C.int;
319 if not Single_Lock or else Global_Lock then
320 Result := pthread_mutex_unlock (L);
321 pragma Assert (Result = 0);
325 procedure Unlock (T : Task_Id) is
326 Result : Interfaces.C.int;
328 if not Single_Lock then
329 Result := pthread_mutex_unlock (T.Common.LL.L'Access);
330 pragma Assert (Result = 0);
339 (Self_ID : ST.Task_Id;
340 Reason : System.Tasking.Task_States)
342 pragma Unreferenced (Reason);
344 Result : Interfaces.C.int;
348 Result := pthread_cond_wait
349 (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access);
351 Result := pthread_cond_wait
352 (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access);
355 -- EINTR is not considered a failure.
357 pragma Assert (Result = 0 or else Result = EINTR);
364 procedure Timed_Sleep
367 Mode : ST.Delay_Modes;
368 Reason : System.Tasking.Task_States;
369 Timedout : out Boolean;
370 Yielded : out Boolean)
372 pragma Unreferenced (Reason);
374 Check_Time : constant Duration := Monotonic_Clock;
376 Request : aliased struct_timeval;
377 Result : Interfaces.C.int;
383 if Mode = Relative then
384 Abs_Time := Duration'Min (Time, Max_Sensible_Delay) + Check_Time;
386 Abs_Time := Duration'Min (Check_Time + Max_Sensible_Delay, Time);
389 if Abs_Time > Check_Time then
390 Request := To_Timeval (Abs_Time);
393 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level
394 or else Self_ID.Pending_Priority_Change;
397 Result := pthread_cond_timedwait
398 (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access,
402 Result := pthread_cond_timedwait
403 (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access,
407 exit when Abs_Time <= Monotonic_Clock;
409 if Result = 0 or Result = EINTR then
410 -- somebody may have called Wakeup for us
415 pragma Assert (Result = ETIMEDOUT
416 or else (Result = -1 and then errno = EAGAIN));
425 procedure Timed_Delay
428 Mode : ST.Delay_Modes)
430 Check_Time : constant Duration := Monotonic_Clock;
432 Request : aliased struct_timeval;
433 Result : Interfaces.C.int;
436 -- Only the little window between deferring abort and
437 -- locking Self_ID is the reason we need to
438 -- check for pending abort and priority change below!
446 Write_Lock (Self_ID);
448 if Mode = Relative then
449 Abs_Time := Time + Check_Time;
451 Abs_Time := Duration'Min (Check_Time + Max_Sensible_Delay, Time);
454 if Abs_Time > Check_Time then
455 Request := To_Timeval (Abs_Time);
456 Self_ID.Common.State := Delay_Sleep;
459 if Self_ID.Pending_Priority_Change then
460 Self_ID.Pending_Priority_Change := False;
461 Self_ID.Common.Base_Priority := Self_ID.New_Base_Priority;
462 Set_Priority (Self_ID, Self_ID.Common.Base_Priority);
465 exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
468 Result := pthread_cond_timedwait (Self_ID.Common.LL.CV'Access,
469 Single_RTS_Lock'Access, Request'Access);
471 Result := pthread_cond_timedwait (Self_ID.Common.LL.CV'Access,
472 Self_ID.Common.LL.L'Access, Request'Access);
475 exit when Abs_Time <= Monotonic_Clock;
477 pragma Assert (Result = 0 or else
478 Result = ETIMEDOUT or else
479 (Result = -1 and then errno = EAGAIN) or else
483 Self_ID.Common.State := Runnable;
493 SSL.Abort_Undefer.all;
496 ---------------------
497 -- Monotonic_Clock --
498 ---------------------
500 function Monotonic_Clock return Duration is
501 type timeval is record
505 pragma Convention (C, timeval);
507 tv : aliased timeval;
509 procedure gettimeofday (tp : access timeval);
510 pragma Import (C, gettimeofday, "gettimeofday", "gettimeofday");
513 gettimeofday (tv'Access);
514 return Duration (tv.tv_sec) + Duration (tv.tv_usec) / 1_000_000.0;
521 function RT_Resolution return Duration is
532 Reason : System.Tasking.Task_States)
534 pragma Unreferenced (Reason);
535 Result : Interfaces.C.int;
537 Result := pthread_cond_signal (T.Common.LL.CV'Access);
538 pragma Assert (Result = 0);
545 procedure Yield (Do_Yield : Boolean := True) is
556 procedure Set_Priority
558 Prio : System.Any_Priority;
559 Loss_Of_Inheritance : Boolean := False)
561 pragma Unreferenced (Loss_Of_Inheritance);
563 Result : Interfaces.C.int;
566 T.Common.Current_Priority := Prio;
567 Result := pthread_setprio (T.Common.LL.Thread, Interfaces.C.int (Prio));
568 pragma Assert (Result /= FUNC_ERR);
575 function Get_Priority (T : Task_Id) return System.Any_Priority is
577 return T.Common.Current_Priority;
584 procedure Enter_Task (Self_ID : Task_Id) is
585 Result : Interfaces.C.int;
588 Self_ID.Common.LL.Thread := pthread_self;
589 Self_ID.Common.LL.LWP := sproc_self;
592 pthread_set_ada_tcb (Self_ID.Common.LL.Thread, To_Address (Self_ID));
594 pragma Assert (Result = 0);
598 for J in Known_Tasks'Range loop
599 if Known_Tasks (J) = null then
600 Known_Tasks (J) := Self_ID;
601 Self_ID.Known_Tasks_Index := J;
613 function New_ATCB (Entry_Num : Task_Entry_Index) return Task_Id is
615 return new Ada_Task_Control_Block (Entry_Num);
622 function Is_Valid_Task return Boolean is
627 -----------------------------
628 -- Register_Foreign_Thread --
629 -----------------------------
631 function Register_Foreign_Thread return Task_Id is
634 end Register_Foreign_Thread;
640 procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is
641 Result : Interfaces.C.int;
642 Cond_Attr : aliased pthread_condattr_t;
645 if not Single_Lock then
646 Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level);
649 Result := pthread_condattr_init (Cond_Attr'Access);
650 pragma Assert (Result = 0 or else Result = ENOMEM);
653 Result := pthread_cond_init (Self_ID.Common.LL.CV'Access,
655 pragma Assert (Result = 0 or else Result = ENOMEM);
661 if not Single_Lock then
662 Result := pthread_mutex_destroy (Self_ID.Common.LL.L'Access);
663 pragma Assert (Result = 0);
669 Result := pthread_condattr_destroy (Cond_Attr'Access);
670 pragma Assert (Result = 0);
677 procedure Create_Task
679 Wrapper : System.Address;
680 Stack_Size : System.Parameters.Size_Type;
681 Priority : System.Any_Priority;
682 Succeeded : out Boolean)
684 Attributes : aliased pthread_attr_t;
685 Adjusted_Stack_Size : Interfaces.C.size_t;
686 Result : Interfaces.C.int;
688 function Thread_Body_Access is new
689 Unchecked_Conversion (System.Address, start_addr);
691 function To_Resource_T is new Unchecked_Conversion
692 (System.Task_Info.Resource_Vector_T, System.OS_Interface.resource_t);
694 use System.Task_Info;
697 if Stack_Size = Unspecified_Size then
698 Adjusted_Stack_Size :=
699 Interfaces.C.size_t (System.Program_Info.Default_Task_Stack);
701 elsif Stack_Size < Minimum_Stack_Size then
702 Adjusted_Stack_Size := Interfaces.C.size_t (Minimum_Stack_Size);
705 Adjusted_Stack_Size := Interfaces.C.size_t (Stack_Size);
708 Result := pthread_attr_init (Attributes'Access);
709 pragma Assert (Result = 0 or else Result = ENOMEM);
716 Result := pthread_attr_setdetachstate (Attributes'Access, 1);
717 pragma Assert (Result = 0);
719 Result := pthread_attr_setstacksize
720 (Attributes'Access, Adjusted_Stack_Size);
721 pragma Assert (Result = 0);
723 if T.Common.Task_Info /= null then
724 Result := pthread_attr_setresources
726 To_Resource_T (T.Common.Task_Info.Thread_Resources));
727 pragma Assert (Result /= FUNC_ERR);
729 if T.Common.Task_Info.Thread_Timeslice /= 0.0 then
731 use System.OS_Interface;
733 Tv : aliased struct_timeval := To_Timeval
734 (T.Common.Task_Info.Thread_Timeslice);
736 Result := pthread_attr_set_tslice
737 (Attributes'Access, Tv'Access);
741 if T.Common.Task_Info.Bound_To_Sproc then
742 Result := pthread_attr_set_boundtosproc
743 (Attributes'Access, PTHREAD_BOUND);
744 Result := pthread_attr_set_bsproc
745 (Attributes'Access, T.Common.Task_Info.Sproc);
750 -- Since the initial signal mask of a thread is inherited from the
751 -- creator, and the Environment task has all its signals masked, we
752 -- do not need to manipulate caller's signal mask at this point.
753 -- All tasks in RTS will have All_Tasks_Mask initially.
755 Result := pthread_create
756 (T.Common.LL.Thread'Access,
758 Thread_Body_Access (Wrapper),
760 pragma Assert (Result = 0 or else Result = EAGAIN);
762 Succeeded := Result = 0;
764 Set_Priority (T, Priority);
766 Result := pthread_attr_destroy (Attributes'Access);
767 pragma Assert (Result /= FUNC_ERR);
774 procedure Finalize_TCB (T : Task_Id) is
775 procedure Free is new
776 Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id);
778 Result : Interfaces.C.int;
782 if not Single_Lock then
783 Result := pthread_mutex_destroy (T.Common.LL.L'Access);
784 pragma Assert (Result = 0);
787 Result := pthread_cond_destroy (T.Common.LL.CV'Access);
788 pragma Assert (Result = 0);
790 if T.Known_Tasks_Index /= -1 then
791 Known_Tasks (T.Known_Tasks_Index) := null;
801 procedure Exit_Task is
802 Result : Interfaces.C.int;
804 Result := pthread_set_ada_tcb (pthread_self, System.Null_Address);
805 pragma Assert (Result = 0);
812 procedure Abort_Task (T : Task_Id) is
813 Result : Interfaces.C.int;
816 pthread_kill (T.Common.LL.Thread,
818 (System.Interrupt_Management.Abort_Task_Interrupt));
819 pragma Assert (Result = 0);
828 function Check_Exit (Self_ID : ST.Task_Id) return Boolean is
829 pragma Unreferenced (Self_ID);
838 function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is
839 pragma Unreferenced (Self_ID);
844 ----------------------
845 -- Environment_Task --
846 ----------------------
848 function Environment_Task return Task_Id is
850 return Environment_Task_Id;
851 end Environment_Task;
857 procedure Lock_RTS is
859 Write_Lock (Single_RTS_Lock'Access, Global_Lock => True);
866 procedure Unlock_RTS is
868 Unlock (Single_RTS_Lock'Access, Global_Lock => True);
875 function Suspend_Task
877 Thread_Self : Thread_Id) return Boolean
880 if T.Common.LL.Thread /= Thread_Self then
881 return pthread_suspend (T.Common.LL.Thread) = 0;
893 Thread_Self : Thread_Id) return Boolean
896 if T.Common.LL.Thread /= Thread_Self then
897 return pthread_resume (T.Common.LL.Thread) = 0;
907 procedure Initialize (Environment_Task : Task_Id) is
909 Environment_Task_Id := Environment_Task;
911 Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level);
912 -- Initialize the lock used to synchronize chain of all ATCBs.
914 Enter_Task (Environment_Task);
916 Set_Priority (Environment_Task,
917 Environment_Task.Common.Current_Priority);
920 --------------------------------
921 -- Initialize_Athread_Library --
922 --------------------------------
924 procedure Initialize_Athread_Library is
925 Result : Interfaces.C.int;
926 Init : aliased pthread_init_struct;
928 package PINF renames System.Program_Info;
929 package C renames Interfaces.C;
932 Init.conf_initsize := C.int (PINF.Pthread_Arena_Size);
933 Init.max_sproc_count := C.int (PINF.Max_Sproc_Count);
934 Init.sproc_stack_size := C.size_t (PINF.Sproc_Stack_Size);
935 Init.os_default_priority := C.int (PINF.Os_Default_Priority);
936 Init.os_sched_signal := C.int (PINF.Pthread_Sched_Signal);
937 Init.guard_pages := C.int (PINF.Stack_Guard_Pages);
938 Init.init_sproc_count := C.int (PINF.Initial_Sproc_Count);
940 Result := pthread_exec_begin (Init'Access);
941 pragma Assert (Result /= FUNC_ERR);
943 if Result = FUNC_ERR then
944 raise Storage_Error; -- Insufficient resources
946 end Initialize_Athread_Library;
948 -- Package initialization
951 Initialize_Athread_Library;
952 end System.Task_Primitives.Operations;