| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT RUN-TIME LIBRARY (GNARL) COMPONENTS -- |
| -- -- |
| -- 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 -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2006, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNARL is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 2, or (at your option) any later ver- -- |
| -- sion. GNARL is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- |
| -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- |
| -- for more details. You should have received a copy of the GNU General -- |
| -- Public License distributed with GNARL; see file COPYING. If not, write -- |
| -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- |
| -- Boston, MA 02110-1301, USA. -- |
| -- -- |
| -- As a special exception, if other files instantiate generics from this -- |
| -- unit, or you link this unit with other files to produce an executable, -- |
| -- this unit does not by itself cause the resulting executable to be -- |
| -- covered by the GNU General Public License. This exception does not -- |
| -- however invalidate any other reasons why the executable file might be -- |
| -- covered by the GNU Public License. -- |
| -- -- |
| -- GNARL was developed by the GNARL team at Florida State University. -- |
| -- Extensive contributions were provided by Ada Core Technologies, Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This is a OpenVMS/Alpha version of this package |
| |
| -- This package contains all the GNULL primitives that interface directly |
| -- with the underlying OS. |
| |
| pragma Polling (Off); |
| -- Turn off polling, we do not want ATC polling to take place during |
| -- tasking operations. It causes infinite loops and other problems. |
| |
| with System.Tasking.Debug; |
| -- used for Known_Tasks |
| |
| with System.OS_Primitives; |
| -- used for Delay_Modes |
| |
| with Interfaces.C; |
| -- used for int |
| -- size_t |
| |
| with System.Soft_Links; |
| -- used for Get_Exc_Stack_Addr |
| -- Abort_Defer/Undefer |
| |
| with Unchecked_Conversion; |
| with Unchecked_Deallocation; |
| |
| package body System.Task_Primitives.Operations is |
| |
| use System.Tasking.Debug; |
| use System.Tasking; |
| use Interfaces.C; |
| use System.OS_Interface; |
| use System.Parameters; |
| use System.OS_Primitives; |
| use type System.OS_Primitives.OS_Time; |
| |
| package SSL renames System.Soft_Links; |
| |
| ---------------- |
| -- Local Data -- |
| ---------------- |
| |
| -- The followings are logically constants, but need to be initialized |
| -- at run time. |
| |
| Single_RTS_Lock : aliased RTS_Lock; |
| -- This is a lock to allow only one thread of control in the RTS at |
| -- a time; it is used to execute in mutual exclusion from all other tasks. |
| -- Used mainly in Single_Lock mode, but also to protect All_Tasks_List |
| |
| ATCB_Key : aliased pthread_key_t; |
| -- Key used to find the Ada Task_Id associated with a thread |
| |
| Environment_Task_Id : Task_Id; |
| -- A variable to hold Task_Id for the environment task. |
| |
| Time_Slice_Val : Integer; |
| pragma Import (C, Time_Slice_Val, "__gl_time_slice_val"); |
| |
| Dispatching_Policy : Character; |
| pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy"); |
| |
| Foreign_Task_Elaborated : aliased Boolean := True; |
| -- Used to identified fake tasks (i.e., non-Ada Threads). |
| |
| -------------------- |
| -- Local Packages -- |
| -------------------- |
| |
| package Specific is |
| |
| procedure Initialize (Environment_Task : Task_Id); |
| pragma Inline (Initialize); |
| -- Initialize various data needed by this package. |
| |
| function Is_Valid_Task return Boolean; |
| pragma Inline (Is_Valid_Task); |
| -- Does executing thread have a TCB? |
| |
| procedure Set (Self_Id : Task_Id); |
| pragma Inline (Set); |
| -- Set the self id for the current task |
| |
| function Self return Task_Id; |
| pragma Inline (Self); |
| -- Return a pointer to the Ada Task Control Block of the calling task |
| |
| end Specific; |
| |
| package body Specific is separate; |
| -- The body of this package is target specific. |
| |
| --------------------------------- |
| -- Support for foreign threads -- |
| --------------------------------- |
| |
| function Register_Foreign_Thread (Thread : Thread_Id) return Task_Id; |
| -- Allocate and Initialize a new ATCB for the current Thread |
| |
| function Register_Foreign_Thread |
| (Thread : Thread_Id) return Task_Id is separate; |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| function To_Task_Id is new Unchecked_Conversion (System.Address, Task_Id); |
| |
| function To_Address is new Unchecked_Conversion (Task_Id, System.Address); |
| |
| function Get_Exc_Stack_Addr return Address; |
| -- Replace System.Soft_Links.Get_Exc_Stack_Addr_NT |
| |
| procedure Timer_Sleep_AST (ID : Address); |
| -- Signal the condition variable when AST fires. |
| |
| procedure Timer_Sleep_AST (ID : Address) is |
| Result : Interfaces.C.int; |
| Self_ID : constant Task_Id := To_Task_Id (ID); |
| begin |
| Self_ID.Common.LL.AST_Pending := False; |
| Result := pthread_cond_signal_int_np (Self_ID.Common.LL.CV'Access); |
| pragma Assert (Result = 0); |
| end Timer_Sleep_AST; |
| |
| ----------------- |
| -- Stack_Guard -- |
| ----------------- |
| |
| -- The underlying thread system sets a guard page at the |
| -- bottom of a thread stack, so nothing is needed. |
| -- ??? Check the comment above |
| |
| procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is |
| pragma Unreferenced (T); |
| pragma Unreferenced (On); |
| begin |
| null; |
| end Stack_Guard; |
| |
| -------------------- |
| -- Get_Thread_Id -- |
| -------------------- |
| |
| function Get_Thread_Id (T : ST.Task_Id) return OSI.Thread_Id is |
| begin |
| return T.Common.LL.Thread; |
| end Get_Thread_Id; |
| |
| ---------- |
| -- Self -- |
| ---------- |
| |
| function Self return Task_Id renames Specific.Self; |
| |
| --------------------- |
| -- Initialize_Lock -- |
| --------------------- |
| |
| -- Note: mutexes and cond_variables needed per-task basis are |
| -- initialized in Initialize_TCB and the Storage_Error is |
| -- handled. Other mutexes (such as RTS_Lock, Memory_Lock...) |
| -- used in RTS is initialized before any status change of RTS. |
| -- Therefore rasing Storage_Error in the following routines |
| -- should be able to be handled safely. |
| |
| procedure Initialize_Lock (Prio : System.Any_Priority; L : access Lock) is |
| Attributes : aliased pthread_mutexattr_t; |
| Result : Interfaces.C.int; |
| |
| begin |
| Result := pthread_mutexattr_init (Attributes'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = ENOMEM then |
| raise Storage_Error; |
| end if; |
| |
| L.Prio_Save := 0; |
| L.Prio := Interfaces.C.int (Prio); |
| |
| Result := pthread_mutex_init (L.L'Access, Attributes'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = ENOMEM then |
| raise Storage_Error; |
| end if; |
| |
| Result := pthread_mutexattr_destroy (Attributes'Access); |
| pragma Assert (Result = 0); |
| end Initialize_Lock; |
| |
| procedure Initialize_Lock (L : access RTS_Lock; Level : Lock_Level) is |
| pragma Unreferenced (Level); |
| |
| Attributes : aliased pthread_mutexattr_t; |
| Result : Interfaces.C.int; |
| |
| begin |
| Result := pthread_mutexattr_init (Attributes'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = ENOMEM then |
| raise Storage_Error; |
| end if; |
| |
| -- Don't use, see comment in s-osinte.ads about ERRORCHECK mutexes??? |
| -- Result := pthread_mutexattr_settype_np |
| -- (Attributes'Access, PTHREAD_MUTEX_ERRORCHECK_NP); |
| -- pragma Assert (Result = 0); |
| |
| -- Result := pthread_mutexattr_setprotocol |
| -- (Attributes'Access, PTHREAD_PRIO_PROTECT); |
| -- pragma Assert (Result = 0); |
| |
| -- Result := pthread_mutexattr_setprioceiling |
| -- (Attributes'Access, Interfaces.C.int (System.Any_Priority'Last)); |
| -- pragma Assert (Result = 0); |
| |
| Result := pthread_mutex_init (L, Attributes'Access); |
| |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = ENOMEM then |
| raise Storage_Error; |
| end if; |
| |
| Result := pthread_mutexattr_destroy (Attributes'Access); |
| pragma Assert (Result = 0); |
| end Initialize_Lock; |
| |
| ------------------- |
| -- Finalize_Lock -- |
| ------------------- |
| |
| procedure Finalize_Lock (L : access Lock) is |
| Result : Interfaces.C.int; |
| begin |
| Result := pthread_mutex_destroy (L.L'Access); |
| pragma Assert (Result = 0); |
| end Finalize_Lock; |
| |
| procedure Finalize_Lock (L : access RTS_Lock) is |
| Result : Interfaces.C.int; |
| begin |
| Result := pthread_mutex_destroy (L); |
| pragma Assert (Result = 0); |
| end Finalize_Lock; |
| |
| ---------------- |
| -- Write_Lock -- |
| ---------------- |
| |
| procedure Write_Lock (L : access Lock; Ceiling_Violation : out Boolean) is |
| Self_ID : constant Task_Id := Self; |
| All_Tasks_Link : constant Task_Id := Self.Common.All_Tasks_Link; |
| Current_Prio : System.Any_Priority; |
| Result : Interfaces.C.int; |
| |
| begin |
| Current_Prio := Get_Priority (Self_ID); |
| |
| -- If there is no other tasks, no need to check priorities |
| |
| if All_Tasks_Link /= Null_Task |
| and then L.Prio < Interfaces.C.int (Current_Prio) |
| then |
| Ceiling_Violation := True; |
| return; |
| end if; |
| |
| Result := pthread_mutex_lock (L.L'Access); |
| pragma Assert (Result = 0); |
| |
| Ceiling_Violation := False; |
| -- Why is this commented out ??? |
| -- L.Prio_Save := Interfaces.C.int (Current_Prio); |
| -- Set_Priority (Self_ID, System.Any_Priority (L.Prio)); |
| end Write_Lock; |
| |
| procedure Write_Lock |
| (L : access RTS_Lock; |
| Global_Lock : Boolean := False) |
| is |
| Result : Interfaces.C.int; |
| begin |
| if not Single_Lock or else Global_Lock then |
| Result := pthread_mutex_lock (L); |
| pragma Assert (Result = 0); |
| end if; |
| end Write_Lock; |
| |
| procedure Write_Lock (T : Task_Id) is |
| Result : Interfaces.C.int; |
| begin |
| if not Single_Lock then |
| Result := pthread_mutex_lock (T.Common.LL.L'Access); |
| pragma Assert (Result = 0); |
| end if; |
| end Write_Lock; |
| |
| --------------- |
| -- Read_Lock -- |
| --------------- |
| |
| procedure Read_Lock (L : access Lock; Ceiling_Violation : out Boolean) is |
| begin |
| Write_Lock (L, Ceiling_Violation); |
| end Read_Lock; |
| |
| ------------ |
| -- Unlock -- |
| ------------ |
| |
| procedure Unlock (L : access Lock) is |
| Result : Interfaces.C.int; |
| begin |
| Result := pthread_mutex_unlock (L.L'Access); |
| pragma Assert (Result = 0); |
| end Unlock; |
| |
| procedure Unlock (L : access RTS_Lock; Global_Lock : Boolean := False) is |
| Result : Interfaces.C.int; |
| begin |
| if not Single_Lock or else Global_Lock then |
| Result := pthread_mutex_unlock (L); |
| pragma Assert (Result = 0); |
| end if; |
| end Unlock; |
| |
| procedure Unlock (T : Task_Id) is |
| Result : Interfaces.C.int; |
| begin |
| if not Single_Lock then |
| Result := pthread_mutex_unlock (T.Common.LL.L'Access); |
| pragma Assert (Result = 0); |
| end if; |
| end Unlock; |
| |
| ----------- |
| -- Sleep -- |
| ----------- |
| |
| procedure Sleep |
| (Self_ID : Task_Id; |
| Reason : System.Tasking.Task_States) |
| is |
| pragma Unreferenced (Reason); |
| Result : Interfaces.C.int; |
| |
| begin |
| if Single_Lock then |
| Result := pthread_cond_wait |
| (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access); |
| else |
| Result := pthread_cond_wait |
| (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access); |
| end if; |
| |
| -- EINTR is not considered a failure |
| |
| pragma Assert (Result = 0 or else Result = EINTR); |
| |
| if Self_ID.Deferral_Level = 0 |
| and then Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level |
| then |
| Unlock (Self_ID); |
| raise Standard'Abort_Signal; |
| end if; |
| end Sleep; |
| |
| ----------------- |
| -- Timed_Sleep -- |
| ----------------- |
| |
| procedure Timed_Sleep |
| (Self_ID : Task_Id; |
| Time : Duration; |
| Mode : ST.Delay_Modes; |
| Reason : System.Tasking.Task_States; |
| Timedout : out Boolean; |
| Yielded : out Boolean) |
| is |
| pragma Unreferenced (Reason); |
| |
| Sleep_Time : OS_Time; |
| Result : Interfaces.C.int; |
| Status : Cond_Value_Type; |
| |
| -- The body below requires more comments ??? |
| |
| begin |
| Timedout := False; |
| Yielded := False; |
| |
| Sleep_Time := To_OS_Time (Time, Mode); |
| |
| if Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level |
| or else Self_ID.Pending_Priority_Change |
| then |
| return; |
| end if; |
| |
| Self_ID.Common.LL.AST_Pending := True; |
| |
| Sys_Setimr |
| (Status, 0, Sleep_Time, |
| Timer_Sleep_AST'Access, To_Address (Self_ID), 0); |
| |
| if (Status and 1) /= 1 then |
| raise Storage_Error; |
| end if; |
| |
| if Single_Lock then |
| Result := pthread_cond_wait |
| (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access); |
| pragma Assert (Result = 0); |
| |
| else |
| Result := pthread_cond_wait |
| (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access); |
| pragma Assert (Result = 0); |
| end if; |
| |
| Yielded := True; |
| |
| if not Self_ID.Common.LL.AST_Pending then |
| Timedout := True; |
| else |
| Sys_Cantim (Status, To_Address (Self_ID), 0); |
| pragma Assert ((Status and 1) = 1); |
| end if; |
| end Timed_Sleep; |
| |
| ----------------- |
| -- Timed_Delay -- |
| ----------------- |
| |
| procedure Timed_Delay |
| (Self_ID : Task_Id; |
| Time : Duration; |
| Mode : ST.Delay_Modes) |
| is |
| Sleep_Time : OS_Time; |
| Result : Interfaces.C.int; |
| Status : Cond_Value_Type; |
| Yielded : Boolean := False; |
| |
| begin |
| if Single_Lock then |
| Lock_RTS; |
| end if; |
| |
| -- More comments required in body below ??? |
| |
| Write_Lock (Self_ID); |
| |
| if Time /= 0.0 or else Mode /= Relative then |
| Sleep_Time := To_OS_Time (Time, Mode); |
| |
| if Mode = Relative or else OS_Clock < Sleep_Time then |
| Self_ID.Common.State := Delay_Sleep; |
| Self_ID.Common.LL.AST_Pending := True; |
| |
| Sys_Setimr |
| (Status, 0, Sleep_Time, |
| Timer_Sleep_AST'Access, To_Address (Self_ID), 0); |
| |
| if (Status and 1) /= 1 then |
| raise Storage_Error; |
| end if; |
| |
| loop |
| if Self_ID.Pending_Priority_Change then |
| Self_ID.Pending_Priority_Change := False; |
| Self_ID.Common.Base_Priority := Self_ID.New_Base_Priority; |
| Set_Priority (Self_ID, Self_ID.Common.Base_Priority); |
| end if; |
| |
| if Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level then |
| Sys_Cantim (Status, To_Address (Self_ID), 0); |
| pragma Assert ((Status and 1) = 1); |
| exit; |
| end if; |
| |
| if Single_Lock then |
| Result := pthread_cond_wait |
| (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access); |
| pragma Assert (Result = 0); |
| else |
| Result := pthread_cond_wait |
| (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access); |
| pragma Assert (Result = 0); |
| end if; |
| |
| Yielded := True; |
| |
| exit when not Self_ID.Common.LL.AST_Pending; |
| end loop; |
| |
| Self_ID.Common.State := Runnable; |
| end if; |
| end if; |
| |
| Unlock (Self_ID); |
| |
| if Single_Lock then |
| Unlock_RTS; |
| end if; |
| |
| if not Yielded then |
| Result := sched_yield; |
| pragma Assert (Result = 0); |
| end if; |
| end Timed_Delay; |
| |
| --------------------- |
| -- Monotonic_Clock -- |
| --------------------- |
| |
| function Monotonic_Clock return Duration |
| renames System.OS_Primitives.Monotonic_Clock; |
| |
| ------------------- |
| -- RT_Resolution -- |
| ------------------- |
| |
| function RT_Resolution return Duration is |
| begin |
| return 10#1.0#E-3; |
| end RT_Resolution; |
| |
| ------------ |
| -- Wakeup -- |
| ------------ |
| |
| procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is |
| pragma Unreferenced (Reason); |
| Result : Interfaces.C.int; |
| begin |
| Result := pthread_cond_signal (T.Common.LL.CV'Access); |
| pragma Assert (Result = 0); |
| end Wakeup; |
| |
| ----------- |
| -- Yield -- |
| ----------- |
| |
| procedure Yield (Do_Yield : Boolean := True) is |
| Result : Interfaces.C.int; |
| pragma Unreferenced (Result); |
| begin |
| if Do_Yield then |
| Result := sched_yield; |
| end if; |
| end Yield; |
| |
| ------------------ |
| -- Set_Priority -- |
| ------------------ |
| |
| procedure Set_Priority |
| (T : Task_Id; |
| Prio : System.Any_Priority; |
| Loss_Of_Inheritance : Boolean := False) |
| is |
| pragma Unreferenced (Loss_Of_Inheritance); |
| |
| Result : Interfaces.C.int; |
| Param : aliased struct_sched_param; |
| |
| begin |
| T.Common.Current_Priority := Prio; |
| Param.sched_priority := Interfaces.C.int (Underlying_Priorities (Prio)); |
| |
| if Time_Slice_Val > 0 then |
| Result := pthread_setschedparam |
| (T.Common.LL.Thread, SCHED_RR, Param'Access); |
| |
| elsif Dispatching_Policy = 'F' or else Time_Slice_Val = 0 then |
| Result := pthread_setschedparam |
| (T.Common.LL.Thread, SCHED_FIFO, Param'Access); |
| |
| else |
| -- SCHED_OTHER priorities are restricted to the range 8 - 15. |
| -- Since the translation from Underlying priorities results |
| -- in a range of 16 - 31, dividing by 2 gives the correct result. |
| |
| Param.sched_priority := Param.sched_priority / 2; |
| Result := pthread_setschedparam |
| (T.Common.LL.Thread, SCHED_OTHER, Param'Access); |
| end if; |
| |
| pragma Assert (Result = 0); |
| end Set_Priority; |
| |
| ------------------ |
| -- Get_Priority -- |
| ------------------ |
| |
| function Get_Priority (T : Task_Id) return System.Any_Priority is |
| begin |
| return T.Common.Current_Priority; |
| end Get_Priority; |
| |
| ---------------- |
| -- Enter_Task -- |
| ---------------- |
| |
| procedure Enter_Task (Self_ID : Task_Id) is |
| begin |
| Self_ID.Common.LL.Thread := pthread_self; |
| |
| Specific.Set (Self_ID); |
| |
| Lock_RTS; |
| |
| for J in Known_Tasks'Range loop |
| if Known_Tasks (J) = null then |
| Known_Tasks (J) := Self_ID; |
| Self_ID.Known_Tasks_Index := J; |
| exit; |
| end if; |
| end loop; |
| |
| Unlock_RTS; |
| end Enter_Task; |
| |
| -------------- |
| -- New_ATCB -- |
| -------------- |
| |
| function New_ATCB (Entry_Num : Task_Entry_Index) return Task_Id is |
| begin |
| return new Ada_Task_Control_Block (Entry_Num); |
| end New_ATCB; |
| |
| ------------------- |
| -- Is_Valid_Task -- |
| ------------------- |
| |
| function Is_Valid_Task return Boolean renames Specific.Is_Valid_Task; |
| |
| ----------------------------- |
| -- Register_Foreign_Thread -- |
| ----------------------------- |
| |
| function Register_Foreign_Thread return Task_Id is |
| begin |
| if Is_Valid_Task then |
| return Self; |
| else |
| return Register_Foreign_Thread (pthread_self); |
| end if; |
| end Register_Foreign_Thread; |
| |
| -------------------- |
| -- Initialize_TCB -- |
| -------------------- |
| |
| procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is |
| Mutex_Attr : aliased pthread_mutexattr_t; |
| Result : Interfaces.C.int; |
| Cond_Attr : aliased pthread_condattr_t; |
| |
| begin |
| -- More comments required in body below ??? |
| |
| if not Single_Lock then |
| Result := pthread_mutexattr_init (Mutex_Attr'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = 0 then |
| Result := pthread_mutex_init (Self_ID.Common.LL.L'Access, |
| Mutex_Attr'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| end if; |
| |
| if Result /= 0 then |
| Succeeded := False; |
| return; |
| end if; |
| |
| Result := pthread_mutexattr_destroy (Mutex_Attr'Access); |
| pragma Assert (Result = 0); |
| end if; |
| |
| Result := pthread_condattr_init (Cond_Attr'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = 0 then |
| Result := pthread_cond_init (Self_ID.Common.LL.CV'Access, |
| Cond_Attr'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| end if; |
| |
| if Result = 0 then |
| Succeeded := True; |
| Self_ID.Common.LL.Exc_Stack_Ptr := new Exc_Stack_T; |
| |
| else |
| if not Single_Lock then |
| Result := pthread_mutex_destroy (Self_ID.Common.LL.L'Access); |
| pragma Assert (Result = 0); |
| end if; |
| |
| Succeeded := False; |
| end if; |
| |
| Result := pthread_condattr_destroy (Cond_Attr'Access); |
| pragma Assert (Result = 0); |
| end Initialize_TCB; |
| |
| ------------------------ |
| -- Get_Exc_Stack_Addr -- |
| ------------------------ |
| |
| function Get_Exc_Stack_Addr return Address is |
| begin |
| return Self.Common.LL.Exc_Stack_Ptr (Exc_Stack_T'Last)'Address; |
| end Get_Exc_Stack_Addr; |
| |
| ----------------- |
| -- Create_Task -- |
| ----------------- |
| |
| procedure Create_Task |
| (T : Task_Id; |
| Wrapper : System.Address; |
| Stack_Size : System.Parameters.Size_Type; |
| Priority : System.Any_Priority; |
| Succeeded : out Boolean) |
| is |
| Attributes : aliased pthread_attr_t; |
| Result : Interfaces.C.int; |
| |
| function Thread_Body_Access is new |
| Unchecked_Conversion (System.Address, Thread_Body); |
| |
| begin |
| -- Since the initial signal mask of a thread is inherited from the |
| -- creator, we need to set our local signal mask mask all signals |
| -- during the creation operation, to make sure the new thread is |
| -- not disturbed by signals before it has set its own Task_Id. |
| |
| Result := pthread_attr_init (Attributes'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result /= 0 then |
| Succeeded := False; |
| return; |
| end if; |
| |
| Result := pthread_attr_setdetachstate |
| (Attributes'Access, PTHREAD_CREATE_DETACHED); |
| pragma Assert (Result = 0); |
| |
| Result := pthread_attr_setstacksize |
| (Attributes'Access, Interfaces.C.size_t (Stack_Size)); |
| pragma Assert (Result = 0); |
| |
| -- This call may be unnecessary, not sure. ??? |
| |
| Result := |
| pthread_attr_setinheritsched |
| (Attributes'Access, PTHREAD_EXPLICIT_SCHED); |
| pragma Assert (Result = 0); |
| |
| Result := pthread_create |
| (T.Common.LL.Thread'Access, |
| Attributes'Access, |
| Thread_Body_Access (Wrapper), |
| To_Address (T)); |
| |
| -- ENOMEM is a valid run-time error. Don't shut down. |
| |
| pragma Assert (Result = 0 |
| or else Result = EAGAIN or else Result = ENOMEM); |
| |
| Succeeded := Result = 0; |
| |
| Result := pthread_attr_destroy (Attributes'Access); |
| pragma Assert (Result = 0); |
| |
| if Succeeded then |
| Set_Priority (T, Priority); |
| end if; |
| end Create_Task; |
| |
| ------------------ |
| -- Finalize_TCB -- |
| ------------------ |
| |
| procedure Finalize_TCB (T : Task_Id) is |
| Result : Interfaces.C.int; |
| Tmp : Task_Id := T; |
| Is_Self : constant Boolean := T = Self; |
| |
| procedure Free is new |
| Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id); |
| |
| procedure Free is new Unchecked_Deallocation |
| (Exc_Stack_T, Exc_Stack_Ptr_T); |
| |
| begin |
| if not Single_Lock then |
| Result := pthread_mutex_destroy (T.Common.LL.L'Access); |
| pragma Assert (Result = 0); |
| end if; |
| |
| Result := pthread_cond_destroy (T.Common.LL.CV'Access); |
| pragma Assert (Result = 0); |
| |
| if T.Known_Tasks_Index /= -1 then |
| Known_Tasks (T.Known_Tasks_Index) := null; |
| end if; |
| |
| Free (T.Common.LL.Exc_Stack_Ptr); |
| |
| Free (Tmp); |
| |
| if Is_Self then |
| Specific.Set (null); |
| end if; |
| end Finalize_TCB; |
| |
| --------------- |
| -- Exit_Task -- |
| --------------- |
| |
| procedure Exit_Task is |
| begin |
| null; |
| end Exit_Task; |
| |
| ---------------- |
| -- Abort_Task -- |
| ---------------- |
| |
| procedure Abort_Task (T : Task_Id) is |
| begin |
| -- Interrupt Server_Tasks may be waiting on an event flag |
| |
| if T.Common.State = Interrupt_Server_Blocked_On_Event_Flag then |
| Wakeup (T, Interrupt_Server_Blocked_On_Event_Flag); |
| end if; |
| end Abort_Task; |
| |
| ---------------- |
| -- Initialize -- |
| ---------------- |
| |
| procedure Initialize (S : in out Suspension_Object) is |
| Mutex_Attr : aliased pthread_mutexattr_t; |
| Cond_Attr : aliased pthread_condattr_t; |
| Result : Interfaces.C.int; |
| begin |
| -- Initialize internal state. It is always initialized to False (ARM |
| -- D.10 par. 6). |
| |
| S.State := False; |
| S.Waiting := False; |
| |
| -- Initialize internal mutex |
| |
| Result := pthread_mutexattr_init (Mutex_Attr'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = ENOMEM then |
| raise Storage_Error; |
| end if; |
| |
| Result := pthread_mutex_init (S.L'Access, Mutex_Attr'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = ENOMEM then |
| Result := pthread_mutexattr_destroy (Mutex_Attr'Access); |
| pragma Assert (Result = 0); |
| |
| raise Storage_Error; |
| end if; |
| |
| Result := pthread_mutexattr_destroy (Mutex_Attr'Access); |
| pragma Assert (Result = 0); |
| |
| -- Initialize internal condition variable |
| |
| Result := pthread_condattr_init (Cond_Attr'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result /= 0 then |
| Result := pthread_mutex_destroy (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| if Result = ENOMEM then |
| raise Storage_Error; |
| end if; |
| end if; |
| |
| Result := pthread_cond_init (S.CV'Access, Cond_Attr'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result /= 0 then |
| Result := pthread_mutex_destroy (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| if Result = ENOMEM then |
| Result := pthread_condattr_destroy (Cond_Attr'Access); |
| pragma Assert (Result = 0); |
| |
| raise Storage_Error; |
| end if; |
| end if; |
| |
| Result := pthread_condattr_destroy (Cond_Attr'Access); |
| pragma Assert (Result = 0); |
| end Initialize; |
| |
| -------------- |
| -- Finalize -- |
| -------------- |
| |
| procedure Finalize (S : in out Suspension_Object) is |
| Result : Interfaces.C.int; |
| begin |
| -- Destroy internal mutex |
| |
| Result := pthread_mutex_destroy (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| -- Destroy internal condition variable |
| |
| Result := pthread_cond_destroy (S.CV'Access); |
| pragma Assert (Result = 0); |
| end Finalize; |
| |
| ------------------- |
| -- Current_State -- |
| ------------------- |
| |
| function Current_State (S : Suspension_Object) return Boolean is |
| begin |
| -- We do not want to use lock on this read operation. State is marked |
| -- as Atomic so that we ensure that the value retrieved is correct. |
| |
| return S.State; |
| end Current_State; |
| |
| --------------- |
| -- Set_False -- |
| --------------- |
| |
| procedure Set_False (S : in out Suspension_Object) is |
| Result : Interfaces.C.int; |
| begin |
| SSL.Abort_Defer.all; |
| |
| Result := pthread_mutex_lock (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| S.State := False; |
| |
| Result := pthread_mutex_unlock (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| SSL.Abort_Undefer.all; |
| end Set_False; |
| |
| -------------- |
| -- Set_True -- |
| -------------- |
| |
| procedure Set_True (S : in out Suspension_Object) is |
| Result : Interfaces.C.int; |
| begin |
| SSL.Abort_Defer.all; |
| |
| Result := pthread_mutex_lock (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| -- If there is already a task waiting on this suspension object then |
| -- we resume it, leaving the state of the suspension object to False, |
| -- as it is specified in ARM D.10 par. 9. Otherwise, it just leaves |
| -- the state to True. |
| |
| if S.Waiting then |
| S.Waiting := False; |
| S.State := False; |
| |
| Result := pthread_cond_signal (S.CV'Access); |
| pragma Assert (Result = 0); |
| else |
| S.State := True; |
| end if; |
| |
| Result := pthread_mutex_unlock (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| SSL.Abort_Undefer.all; |
| end Set_True; |
| |
| ------------------------ |
| -- Suspend_Until_True -- |
| ------------------------ |
| |
| procedure Suspend_Until_True (S : in out Suspension_Object) is |
| Result : Interfaces.C.int; |
| begin |
| SSL.Abort_Defer.all; |
| |
| Result := pthread_mutex_lock (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| if S.Waiting then |
| -- Program_Error must be raised upon calling Suspend_Until_True |
| -- if another task is already waiting on that suspension object |
| -- (ARM D.10 par. 10). |
| |
| Result := pthread_mutex_unlock (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| SSL.Abort_Undefer.all; |
| |
| raise Program_Error; |
| else |
| -- Suspend the task if the state is False. Otherwise, the task |
| -- continues its execution, and the state of the suspension object |
| -- is set to False (ARM D.10 par. 9). |
| |
| if S.State then |
| S.State := False; |
| else |
| S.Waiting := True; |
| Result := pthread_cond_wait (S.CV'Access, S.L'Access); |
| end if; |
| |
| Result := pthread_mutex_unlock (S.L'Access); |
| pragma Assert (Result = 0); |
| |
| SSL.Abort_Undefer.all; |
| end if; |
| end Suspend_Until_True; |
| |
| ---------------- |
| -- Check_Exit -- |
| ---------------- |
| |
| -- Dummy version |
| |
| function Check_Exit (Self_ID : ST.Task_Id) return Boolean is |
| pragma Unreferenced (Self_ID); |
| begin |
| return True; |
| end Check_Exit; |
| |
| -------------------- |
| -- Check_No_Locks -- |
| -------------------- |
| |
| function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is |
| pragma Unreferenced (Self_ID); |
| begin |
| return True; |
| end Check_No_Locks; |
| |
| ---------------------- |
| -- Environment_Task -- |
| ---------------------- |
| |
| function Environment_Task return Task_Id is |
| begin |
| return Environment_Task_Id; |
| end Environment_Task; |
| |
| -------------- |
| -- Lock_RTS -- |
| -------------- |
| |
| procedure Lock_RTS is |
| begin |
| Write_Lock (Single_RTS_Lock'Access, Global_Lock => True); |
| end Lock_RTS; |
| |
| ---------------- |
| -- Unlock_RTS -- |
| ---------------- |
| |
| procedure Unlock_RTS is |
| begin |
| Unlock (Single_RTS_Lock'Access, Global_Lock => True); |
| end Unlock_RTS; |
| |
| ------------------ |
| -- Suspend_Task -- |
| ------------------ |
| |
| function Suspend_Task |
| (T : ST.Task_Id; |
| Thread_Self : Thread_Id) return Boolean |
| is |
| pragma Unreferenced (T); |
| pragma Unreferenced (Thread_Self); |
| begin |
| return False; |
| end Suspend_Task; |
| |
| ----------------- |
| -- Resume_Task -- |
| ----------------- |
| |
| function Resume_Task |
| (T : ST.Task_Id; |
| Thread_Self : Thread_Id) return Boolean |
| is |
| pragma Unreferenced (T); |
| pragma Unreferenced (Thread_Self); |
| begin |
| return False; |
| end Resume_Task; |
| |
| ---------------- |
| -- Initialize -- |
| ---------------- |
| |
| procedure Initialize (Environment_Task : Task_Id) is |
| begin |
| Environment_Task_Id := Environment_Task; |
| |
| SSL.Get_Exc_Stack_Addr := Get_Exc_Stack_Addr'Access; |
| |
| -- Initialize the lock used to synchronize chain of all ATCBs |
| |
| Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level); |
| |
| Specific.Initialize (Environment_Task); |
| |
| Enter_Task (Environment_Task); |
| end Initialize; |
| |
| end System.Task_Primitives.Operations; |
