| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNU ADA 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) 1992-2003, 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, 59 Temple Place - Suite 330, Boston, -- |
| -- MA 02111-1307, 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 IRIX (pthread library) 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 Interfaces.C; |
| -- used for int |
| -- size_t |
| |
| with System.Task_Info; |
| |
| with System.Tasking.Debug; |
| -- used for Known_Tasks |
| |
| with System.IO; |
| -- used for Put_Line |
| |
| with System.Interrupt_Management; |
| -- used for Keep_Unmasked |
| -- Abort_Task_Interrupt |
| -- Interrupt_ID |
| |
| with System.Interrupt_Management.Operations; |
| -- used for Set_Interrupt_Mask |
| -- All_Tasks_Mask |
| pragma Elaborate_All (System.Interrupt_Management.Operations); |
| |
| with System.Parameters; |
| -- used for Size_Type |
| |
| with System.Tasking; |
| -- used for Ada_Task_Control_Block |
| -- Task_ID |
| |
| with System.Soft_Links; |
| -- used for Defer/Undefer_Abort |
| |
| -- Note that we do not use System.Tasking.Initialization directly since |
| -- this is a higher level package that we shouldn't depend on. For example |
| -- when using the restricted run time, it is replaced by |
| -- System.Tasking.Restricted.Initialization |
| |
| with System.Program_Info; |
| -- used for Default_Task_Stack |
| -- Default_Time_Slice |
| -- Stack_Guard_Pages |
| -- Pthread_Sched_Signal |
| -- Pthread_Arena_Size |
| |
| with System.OS_Interface; |
| -- used for various type, constant, and operations |
| |
| with System.OS_Primitives; |
| -- used for Delay_Modes |
| |
| with Unchecked_Conversion; |
| with Unchecked_Deallocation; |
| |
| package body System.Task_Primitives.Operations is |
| |
| use System.Tasking; |
| use System.Tasking.Debug; |
| use Interfaces.C; |
| use System.OS_Interface; |
| use System.OS_Primitives; |
| use System.Parameters; |
| |
| 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. |
| |
| Locking_Policy : Character; |
| pragma Import (C, Locking_Policy, "__gl_locking_policy"); |
| |
| Real_Time_Clock_Id : constant clockid_t := CLOCK_REALTIME; |
| |
| Unblocked_Signal_Mask : aliased sigset_t; |
| |
| 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_Address is new Unchecked_Conversion (Task_ID, System.Address); |
| |
| procedure Abort_Handler (Sig : Signal); |
| -- Signal handler used to implement asynchronous abort. |
| |
| ------------------- |
| -- Abort_Handler -- |
| ------------------- |
| |
| procedure Abort_Handler (Sig : Signal) is |
| pragma Unreferenced (Sig); |
| |
| T : constant Task_ID := Self; |
| Result : Interfaces.C.int; |
| Old_Set : aliased sigset_t; |
| |
| begin |
| -- It is not safe to raise an exception when using ZCX and the GCC |
| -- exception handling mechanism. |
| |
| if ZCX_By_Default and then GCC_ZCX_Support then |
| return; |
| end if; |
| |
| if T.Deferral_Level = 0 |
| and then T.Pending_ATC_Level < T.ATC_Nesting_Level |
| then |
| -- Make sure signals used for RTS internal purpose are unmasked |
| |
| Result := pthread_sigmask |
| (SIG_UNBLOCK, |
| Unblocked_Signal_Mask'Unchecked_Access, |
| Old_Set'Unchecked_Access); |
| pragma Assert (Result = 0); |
| |
| raise Standard'Abort_Signal; |
| end if; |
| end Abort_Handler; |
| |
| ----------------- |
| -- Stack_Guard -- |
| ----------------- |
| |
| -- The underlying thread system sets a guard page at the |
| -- bottom of a thread stack, so nothing is needed. |
| |
| procedure Stack_Guard (T : ST.Task_ID; On : Boolean) is |
| pragma Unreferenced (On); |
| pragma Unreferenced (T); |
| 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; |
| |
| if Locking_Policy = 'C' then |
| Result := pthread_mutexattr_setprotocol |
| (Attributes'Access, PTHREAD_PRIO_PROTECT); |
| pragma Assert (Result = 0); |
| |
| Result := pthread_mutexattr_setprioceiling |
| (Attributes'Access, Interfaces.C.int (Prio)); |
| pragma Assert (Result = 0); |
| end if; |
| |
| Result := pthread_mutex_init (L, Attributes'Access); |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = ENOMEM then |
| Result := pthread_mutexattr_destroy (Attributes'Access); |
| 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; |
| |
| if Locking_Policy = 'C' then |
| 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); |
| end if; |
| |
| Result := pthread_mutex_init (L, Attributes'Access); |
| |
| pragma Assert (Result = 0 or else Result = ENOMEM); |
| |
| if Result = ENOMEM then |
| Result := pthread_mutexattr_destroy (Attributes'Access); |
| raise Storage_Error; |
| end if; |
| |
| Result := pthread_mutexattr_destroy (Attributes'Access); |
| end Initialize_Lock; |
| |
| ------------------- |
| -- Finalize_Lock -- |
| ------------------- |
| |
| procedure Finalize_Lock (L : access Lock) is |
| Result : Interfaces.C.int; |
| begin |
| Result := pthread_mutex_destroy (L); |
| 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 |
| Result : Interfaces.C.int; |
| begin |
| Result := pthread_mutex_lock (L); |
| Ceiling_Violation := Result = EINVAL; |
| |
| -- Assumes the cause of EINVAL is a priority ceiling violation |
| |
| pragma Assert (Result = 0 or else Result = EINVAL); |
| 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); |
| 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 : ST.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); |
| end Sleep; |
| |
| ----------------- |
| -- Timed_Sleep -- |
| ----------------- |
| |
| procedure Timed_Sleep |
| (Self_ID : Task_ID; |
| Time : Duration; |
| Mode : ST.Delay_Modes; |
| Reason : Task_States; |
| Timedout : out Boolean; |
| Yielded : out Boolean) |
| is |
| pragma Unreferenced (Reason); |
| |
| Check_Time : constant Duration := Monotonic_Clock; |
| Abs_Time : Duration; |
| Request : aliased timespec; |
| Result : Interfaces.C.int; |
| |
| begin |
| Timedout := True; |
| Yielded := False; |
| |
| if Mode = Relative then |
| Abs_Time := Duration'Min (Time, Max_Sensible_Delay) + Check_Time; |
| else |
| Abs_Time := Duration'Min (Check_Time + Max_Sensible_Delay, Time); |
| end if; |
| |
| if Abs_Time > Check_Time then |
| Request := To_Timespec (Abs_Time); |
| |
| loop |
| exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level |
| or else Self_ID.Pending_Priority_Change; |
| |
| if Single_Lock then |
| Result := pthread_cond_timedwait |
| (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access, |
| Request'Access); |
| |
| else |
| Result := pthread_cond_timedwait |
| (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access, |
| Request'Access); |
| end if; |
| |
| exit when Abs_Time <= Monotonic_Clock; |
| |
| if Result = 0 or else errno = EINTR then |
| Timedout := False; |
| exit; |
| end if; |
| end loop; |
| end if; |
| end Timed_Sleep; |
| |
| ----------------- |
| -- Timed_Delay -- |
| ----------------- |
| |
| -- This is for use in implementing delay statements, so |
| -- we assume the caller is abort-deferred but is holding |
| -- no locks. |
| |
| procedure Timed_Delay |
| (Self_ID : Task_ID; |
| Time : Duration; |
| Mode : ST.Delay_Modes) |
| is |
| Check_Time : constant Duration := Monotonic_Clock; |
| Abs_Time : Duration; |
| Request : aliased timespec; |
| Result : Interfaces.C.int; |
| |
| begin |
| -- Only the little window between deferring abort and |
| -- locking Self_ID is the reason we need to |
| -- check for pending abort and priority change below! :( |
| |
| SSL.Abort_Defer.all; |
| |
| if Single_Lock then |
| Lock_RTS; |
| end if; |
| |
| Write_Lock (Self_ID); |
| |
| if Mode = Relative then |
| Abs_Time := Time + Check_Time; |
| else |
| Abs_Time := Duration'Min (Check_Time + Max_Sensible_Delay, Time); |
| end if; |
| |
| if Abs_Time > Check_Time then |
| Request := To_Timespec (Abs_Time); |
| Self_ID.Common.State := Delay_Sleep; |
| |
| 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; |
| |
| exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level; |
| |
| Result := pthread_cond_timedwait (Self_ID.Common.LL.CV'Access, |
| Self_ID.Common.LL.L'Access, Request'Access); |
| exit when Abs_Time <= Monotonic_Clock; |
| |
| pragma Assert (Result = 0 |
| or else Result = ETIMEDOUT |
| or else Result = EINTR); |
| end loop; |
| |
| Self_ID.Common.State := Runnable; |
| end if; |
| |
| Unlock (Self_ID); |
| |
| if Single_Lock then |
| Unlock_RTS; |
| end if; |
| |
| Yield; |
| SSL.Abort_Undefer.all; |
| end Timed_Delay; |
| |
| --------------------- |
| -- Monotonic_Clock -- |
| --------------------- |
| |
| function Monotonic_Clock return Duration is |
| TS : aliased timespec; |
| Result : Interfaces.C.int; |
| begin |
| Result := clock_gettime (Real_Time_Clock_Id, TS'Unchecked_Access); |
| pragma Assert (Result = 0); |
| return To_Duration (TS); |
| end Monotonic_Clock; |
| |
| ------------------- |
| -- RT_Resolution -- |
| ------------------- |
| |
| function RT_Resolution return Duration is |
| begin |
| -- The clock_getres (Real_Time_Clock_Id) function appears to return |
| -- the interrupt resolution of the realtime clock and not the actual |
| -- resolution of reading the clock. Even though this last value is |
| -- only guaranteed to be 100 Hz, at least the Origin 200 appears to |
| -- have a microsecond resolution or better. |
| -- ??? We should figure out a method to return the right value on |
| -- all SGI hardware. |
| |
| return 0.000_001; -- Assume microsecond resolution of clock |
| end RT_Resolution; |
| |
| ------------ |
| -- Wakeup -- |
| ------------ |
| |
| procedure Wakeup (T : ST.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; |
| Sched_Policy : Interfaces.C.int; |
| |
| use type System.Task_Info.Task_Info_Type; |
| |
| function To_Int is new Unchecked_Conversion |
| (System.Task_Info.Thread_Scheduling_Policy, Interfaces.C.int); |
| |
| begin |
| T.Common.Current_Priority := Prio; |
| Param.sched_priority := Interfaces.C.int (Prio); |
| |
| if T.Common.Task_Info /= null then |
| Sched_Policy := To_Int (T.Common.Task_Info.Policy); |
| else |
| Sched_Policy := SCHED_FIFO; |
| end if; |
| |
| Result := pthread_setschedparam (T.Common.LL.Thread, Sched_Policy, |
| Param'Access); |
| 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 |
| Result : Interfaces.C.int; |
| |
| function To_Int is new Unchecked_Conversion |
| (System.Task_Info.CPU_Number, Interfaces.C.int); |
| |
| use System.Task_Info; |
| |
| begin |
| Self_ID.Common.LL.Thread := pthread_self; |
| Specific.Set (Self_ID); |
| |
| if Self_ID.Common.Task_Info /= null |
| and then Self_ID.Common.Task_Info.Scope = PTHREAD_SCOPE_SYSTEM |
| and then Self_ID.Common.Task_Info.Runon_CPU /= ANY_CPU |
| then |
| Result := pthread_setrunon_np |
| (To_Int (Self_ID.Common.Task_Info.Runon_CPU)); |
| pragma Assert (Result = 0); |
| end if; |
| |
| 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 |
| Result : Interfaces.C.int; |
| Cond_Attr : aliased pthread_condattr_t; |
| |
| begin |
| if not Single_Lock then |
| Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level); |
| 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; |
| 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; |
| |
| ----------------- |
| -- 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 |
| use System.Task_Info; |
| |
| Attributes : aliased pthread_attr_t; |
| Sched_Param : aliased struct_sched_param; |
| Adjusted_Stack_Size : Interfaces.C.size_t; |
| Result : Interfaces.C.int; |
| |
| function Thread_Body_Access is new |
| Unchecked_Conversion (System.Address, Thread_Body); |
| |
| function To_Int is new Unchecked_Conversion |
| (System.Task_Info.Thread_Scheduling_Scope, Interfaces.C.int); |
| function To_Int is new Unchecked_Conversion |
| (System.Task_Info.Thread_Scheduling_Inheritance, Interfaces.C.int); |
| function To_Int is new Unchecked_Conversion |
| (System.Task_Info.Thread_Scheduling_Policy, Interfaces.C.int); |
| |
| begin |
| if Stack_Size = System.Parameters.Unspecified_Size then |
| Adjusted_Stack_Size := |
| Interfaces.C.size_t (System.Program_Info.Default_Task_Stack); |
| |
| elsif Stack_Size < Size_Type (Minimum_Stack_Size) then |
| Adjusted_Stack_Size := |
| Interfaces.C.size_t (Minimum_Stack_Size); |
| |
| else |
| Adjusted_Stack_Size := Interfaces.C.size_t (Stack_Size); |
| end if; |
| |
| 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, Adjusted_Stack_Size); |
| pragma Assert (Result = 0); |
| |
| if T.Common.Task_Info /= null then |
| Result := pthread_attr_setscope |
| (Attributes'Access, To_Int (T.Common.Task_Info.Scope)); |
| pragma Assert (Result = 0); |
| |
| Result := pthread_attr_setinheritsched |
| (Attributes'Access, To_Int (T.Common.Task_Info.Inheritance)); |
| pragma Assert (Result = 0); |
| |
| Result := pthread_attr_setschedpolicy |
| (Attributes'Access, To_Int (T.Common.Task_Info.Policy)); |
| pragma Assert (Result = 0); |
| |
| Sched_Param.sched_priority := |
| Interfaces.C.int (T.Common.Task_Info.Priority); |
| |
| Result := pthread_attr_setschedparam |
| (Attributes'Access, Sched_Param'Access); |
| pragma Assert (Result = 0); |
| end if; |
| |
| -- Since the initial signal mask of a thread is inherited from the |
| -- creator, and the Environment task has all its signals masked, we |
| -- do not need to manipulate caller's signal mask at this point. |
| -- All tasks in RTS will have All_Tasks_Mask initially. |
| |
| Result := pthread_create |
| (T.Common.LL.Thread'Access, |
| Attributes'Access, |
| Thread_Body_Access (Wrapper), |
| To_Address (T)); |
| |
| if Result /= 0 |
| and then T.Common.Task_Info /= null |
| and then T.Common.Task_Info.Scope = PTHREAD_SCOPE_SYSTEM |
| then |
| -- The pthread_create call may have failed because we |
| -- asked for a system scope pthread and none were |
| -- available (probably because the program was not executed |
| -- by the superuser). Let's try for a process scope pthread |
| -- instead of raising Tasking_Error. |
| |
| System.IO.Put_Line |
| ("Request for PTHREAD_SCOPE_SYSTEM in Task_Info pragma for task"); |
| System.IO.Put (""""); |
| System.IO.Put (T.Common.Task_Image (1 .. T.Common.Task_Image_Len)); |
| System.IO.Put_Line (""" could not be honored. "); |
| System.IO.Put_Line ("Scope changed to PTHREAD_SCOPE_PROCESS"); |
| |
| T.Common.Task_Info.Scope := PTHREAD_SCOPE_PROCESS; |
| Result := pthread_attr_setscope |
| (Attributes'Access, To_Int (T.Common.Task_Info.Scope)); |
| pragma Assert (Result = 0); |
| |
| Result := pthread_create |
| (T.Common.LL.Thread'Access, |
| Attributes'Access, |
| Thread_Body_Access (Wrapper), |
| To_Address (T)); |
| end if; |
| |
| pragma Assert (Result = 0 or else Result = EAGAIN); |
| |
| Succeeded := Result = 0; |
| |
| -- The following needs significant commenting ??? |
| |
| if T.Common.Task_Info /= null then |
| T.Common.Base_Priority := T.Common.Task_Info.Priority; |
| Set_Priority (T, T.Common.Task_Info.Priority); |
| else |
| Set_Priority (T, Priority); |
| end if; |
| |
| Result := pthread_attr_destroy (Attributes'Access); |
| pragma Assert (Result = 0); |
| 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); |
| |
| 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 (Tmp); |
| |
| if Is_Self then |
| Result := pthread_setspecific (ATCB_Key, System.Null_Address); |
| pragma Assert (Result = 0); |
| end if; |
| |
| end Finalize_TCB; |
| |
| --------------- |
| -- Exit_Task -- |
| --------------- |
| |
| procedure Exit_Task is |
| begin |
| Specific.Set (null); |
| end Exit_Task; |
| |
| ---------------- |
| -- Abort_Task -- |
| ---------------- |
| |
| procedure Abort_Task (T : Task_ID) is |
| Result : Interfaces.C.int; |
| |
| begin |
| Result := pthread_kill (T.Common.LL.Thread, |
| Signal (System.Interrupt_Management.Abort_Task_Interrupt)); |
| pragma Assert (Result = 0); |
| end Abort_Task; |
| |
| ---------------- |
| -- 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 |
| act : aliased struct_sigaction; |
| old_act : aliased struct_sigaction; |
| Tmp_Set : aliased sigset_t; |
| Result : Interfaces.C.int; |
| |
| function State (Int : System.Interrupt_Management.Interrupt_ID) |
| return Character; |
| pragma Import (C, State, "__gnat_get_interrupt_state"); |
| -- Get interrupt state. Defined in a-init.c. The input argument is |
| -- the interrupt number, and the result is one of the following: |
| |
| Default : constant Character := 's'; |
| -- 'n' this interrupt not set by any Interrupt_State pragma |
| -- 'u' Interrupt_State pragma set state to User |
| -- 'r' Interrupt_State pragma set state to Runtime |
| -- 's' Interrupt_State pragma set state to System (use "default" |
| -- system handler) |
| |
| begin |
| Environment_Task_ID := Environment_Task; |
| |
| -- 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); |
| |
| -- Install the abort-signal handler |
| |
| if State (System.Interrupt_Management.Abort_Task_Interrupt) |
| /= Default |
| then |
| act.sa_flags := 0; |
| act.sa_handler := Abort_Handler'Address; |
| |
| Result := sigemptyset (Tmp_Set'Access); |
| pragma Assert (Result = 0); |
| act.sa_mask := Tmp_Set; |
| |
| Result := |
| sigaction ( |
| Signal (System.Interrupt_Management.Abort_Task_Interrupt), |
| act'Unchecked_Access, |
| old_act'Unchecked_Access); |
| pragma Assert (Result = 0); |
| end if; |
| end Initialize; |
| |
| begin |
| declare |
| Result : Interfaces.C.int; |
| |
| begin |
| -- Mask Environment task for all signals. The original mask of the |
| -- Environment task will be recovered by Interrupt_Server task |
| -- during the elaboration of s-interr.adb. |
| |
| System.Interrupt_Management.Operations.Set_Interrupt_Mask |
| (System.Interrupt_Management.Operations.All_Tasks_Mask'Access); |
| |
| -- Prepare the set of signals that should unblocked in all tasks |
| |
| Result := sigemptyset (Unblocked_Signal_Mask'Access); |
| pragma Assert (Result = 0); |
| |
| for J in Interrupt_Management.Interrupt_ID loop |
| if System.Interrupt_Management.Keep_Unmasked (J) then |
| Result := sigaddset (Unblocked_Signal_Mask'Access, Signal (J)); |
| pragma Assert (Result = 0); |
| end if; |
| end loop; |
| |
| -- Pick the highest resolution Clock for Clock_Realtime |
| -- ??? This code currently doesn't work (see c94007[ab] for example) |
| -- |
| -- if syssgi (SGI_CYCLECNTR_SIZE) = 64 then |
| -- Real_Time_Clock_Id := CLOCK_SGI_CYCLE; |
| -- else |
| -- Real_Time_Clock_Id := CLOCK_REALTIME; |
| -- end if; |
| end; |
| end System.Task_Primitives.Operations; |
