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Diffstat (limited to 'gcc-4.8.1/gcc/ada/s-taprop-mingw.adb')
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diff --git a/gcc-4.8.1/gcc/ada/s-taprop-mingw.adb b/gcc-4.8.1/gcc/ada/s-taprop-mingw.adb new file mode 100644 index 000000000..75d81cb63 --- /dev/null +++ b/gcc-4.8.1/gcc/ada/s-taprop-mingw.adb @@ -0,0 +1,1392 @@ +------------------------------------------------------------------------------ +-- -- +-- 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) 1992-2012, 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 3, or (at your option) any later ver- -- +-- sion. GNAT 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. -- +-- -- +-- As a special exception under Section 7 of GPL version 3, you are granted -- +-- additional permissions described in the GCC Runtime Library Exception, -- +-- version 3.1, as published by the Free Software Foundation. -- +-- -- +-- You should have received a copy of the GNU General Public License and -- +-- a copy of the GCC Runtime Library Exception along with this program; -- +-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- +-- <http://www.gnu.org/licenses/>. -- +-- -- +-- GNARL was developed by the GNARL team at Florida State University. -- +-- Extensive contributions were provided by Ada Core Technologies, Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- This is a NT (native) 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; +with Interfaces.C.Strings; + +with System.Float_Control; +with System.Interrupt_Management; +with System.Multiprocessors; +with System.OS_Primitives; +with System.Task_Info; +with System.Tasking.Debug; +with System.Win32.Ext; + +with System.Soft_Links; +-- We use System.Soft_Links instead of System.Tasking.Initialization because +-- the later 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.Stages. + +package body System.Task_Primitives.Operations is + + package SSL renames System.Soft_Links; + + use Interfaces.C; + use Interfaces.C.Strings; + use System.OS_Interface; + use System.OS_Primitives; + use System.Parameters; + use System.Task_Info; + use System.Tasking; + use System.Tasking.Debug; + use System.Win32; + use System.Win32.Ext; + + pragma Link_With ("-Xlinker --stack=0x200000,0x1000"); + -- Change the default stack size (2 MB) for tasking programs on Windows. + -- This allows about 1000 tasks running at the same time. Note that + -- we set the stack size for non tasking programs on System unit. + -- Also note that under Windows XP, we use a Windows XP extension to + -- specify the stack size on a per task basis, as done under other OSes. + + --------------------- + -- Local Functions -- + --------------------- + + procedure InitializeCriticalSection (pCriticalSection : access RTS_Lock); + procedure InitializeCriticalSection + (pCriticalSection : access CRITICAL_SECTION); + pragma Import + (Stdcall, InitializeCriticalSection, "InitializeCriticalSection"); + + procedure EnterCriticalSection (pCriticalSection : access RTS_Lock); + procedure EnterCriticalSection + (pCriticalSection : access CRITICAL_SECTION); + pragma Import (Stdcall, EnterCriticalSection, "EnterCriticalSection"); + + procedure LeaveCriticalSection (pCriticalSection : access RTS_Lock); + procedure LeaveCriticalSection (pCriticalSection : access CRITICAL_SECTION); + pragma Import (Stdcall, LeaveCriticalSection, "LeaveCriticalSection"); + + procedure DeleteCriticalSection (pCriticalSection : access RTS_Lock); + procedure DeleteCriticalSection + (pCriticalSection : access CRITICAL_SECTION); + pragma Import (Stdcall, DeleteCriticalSection, "DeleteCriticalSection"); + + ---------------- + -- Local Data -- + ---------------- + + Environment_Task_Id : Task_Id; + -- A variable to hold Task_Id for the environment task + + 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 + + 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"); + + function Get_Policy (Prio : System.Any_Priority) return Character; + pragma Import (C, Get_Policy, "__gnat_get_specific_dispatching"); + -- Get priority specific dispatching policy + + Foreign_Task_Elaborated : aliased Boolean := True; + -- Used to identified fake tasks (i.e., non-Ada Threads) + + Null_Thread_Id : constant Thread_Id := 0; + -- Constant to indicate that the thread identifier has not yet been + -- initialized. + + ------------------------------------ + -- The thread local storage index -- + ------------------------------------ + + TlsIndex : DWORD; + pragma Export (Ada, TlsIndex); + -- To ensure that this variable won't be local to this package, since + -- in some cases, inlining forces this variable to be global anyway. + + -------------------- + -- Local Packages -- + -------------------- + + package Specific is + + 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 + + end Specific; + + package body Specific is + + function Is_Valid_Task return Boolean is + begin + return TlsGetValue (TlsIndex) /= System.Null_Address; + end Is_Valid_Task; + + procedure Set (Self_Id : Task_Id) is + Succeeded : BOOL; + begin + Succeeded := TlsSetValue (TlsIndex, To_Address (Self_Id)); + pragma Assert (Succeeded = Win32.TRUE); + end Set; + + end Specific; + + ---------------------------------- + -- ATCB allocation/deallocation -- + ---------------------------------- + + package body ATCB_Allocation is separate; + -- The body of this package is shared across several targets + + --------------------------------- + -- 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; + + ---------------------------------- + -- Condition Variable Functions -- + ---------------------------------- + + procedure Initialize_Cond (Cond : not null access Condition_Variable); + -- Initialize given condition variable Cond + + procedure Finalize_Cond (Cond : not null access Condition_Variable); + -- Finalize given condition variable Cond + + procedure Cond_Signal (Cond : not null access Condition_Variable); + -- Signal condition variable Cond + + procedure Cond_Wait + (Cond : not null access Condition_Variable; + L : not null access RTS_Lock); + -- Wait on conditional variable Cond, using lock L + + procedure Cond_Timed_Wait + (Cond : not null access Condition_Variable; + L : not null access RTS_Lock; + Rel_Time : Duration; + Timed_Out : out Boolean; + Status : out Integer); + -- Do timed wait on condition variable Cond using lock L. The duration + -- of the timed wait is given by Rel_Time. When the condition is + -- signalled, Timed_Out shows whether or not a time out occurred. + -- Status is only valid if Timed_Out is False, in which case it + -- shows whether Cond_Timed_Wait completed successfully. + + --------------------- + -- Initialize_Cond -- + --------------------- + + procedure Initialize_Cond (Cond : not null access Condition_Variable) is + hEvent : HANDLE; + begin + hEvent := CreateEvent (null, Win32.TRUE, Win32.FALSE, Null_Ptr); + pragma Assert (hEvent /= 0); + Cond.all := Condition_Variable (hEvent); + end Initialize_Cond; + + ------------------- + -- Finalize_Cond -- + ------------------- + + -- No such problem here, DosCloseEventSem has been derived. + -- What does such refer to in above comment??? + + procedure Finalize_Cond (Cond : not null access Condition_Variable) is + Result : BOOL; + begin + Result := CloseHandle (HANDLE (Cond.all)); + pragma Assert (Result = Win32.TRUE); + end Finalize_Cond; + + ----------------- + -- Cond_Signal -- + ----------------- + + procedure Cond_Signal (Cond : not null access Condition_Variable) is + Result : BOOL; + begin + Result := SetEvent (HANDLE (Cond.all)); + pragma Assert (Result = Win32.TRUE); + end Cond_Signal; + + --------------- + -- Cond_Wait -- + --------------- + + -- Pre-condition: Cond is posted + -- L is locked. + + -- Post-condition: Cond is posted + -- L is locked. + + procedure Cond_Wait + (Cond : not null access Condition_Variable; + L : not null access RTS_Lock) + is + Result : DWORD; + Result_Bool : BOOL; + + begin + -- Must reset Cond BEFORE L is unlocked + + Result_Bool := ResetEvent (HANDLE (Cond.all)); + pragma Assert (Result_Bool = Win32.TRUE); + Unlock (L, Global_Lock => True); + + -- No problem if we are interrupted here: if the condition is signaled, + -- WaitForSingleObject will simply not block + + Result := WaitForSingleObject (HANDLE (Cond.all), Wait_Infinite); + pragma Assert (Result = 0); + + Write_Lock (L, Global_Lock => True); + end Cond_Wait; + + --------------------- + -- Cond_Timed_Wait -- + --------------------- + + -- Pre-condition: Cond is posted + -- L is locked. + + -- Post-condition: Cond is posted + -- L is locked. + + procedure Cond_Timed_Wait + (Cond : not null access Condition_Variable; + L : not null access RTS_Lock; + Rel_Time : Duration; + Timed_Out : out Boolean; + Status : out Integer) + is + Time_Out_Max : constant DWORD := 16#FFFF0000#; + -- NT 4 can't handle excessive timeout values (e.g. DWORD'Last - 1) + + Time_Out : DWORD; + Result : BOOL; + Wait_Result : DWORD; + + begin + -- Must reset Cond BEFORE L is unlocked + + Result := ResetEvent (HANDLE (Cond.all)); + pragma Assert (Result = Win32.TRUE); + Unlock (L, Global_Lock => True); + + -- No problem if we are interrupted here: if the condition is signaled, + -- WaitForSingleObject will simply not block. + + if Rel_Time <= 0.0 then + Timed_Out := True; + Wait_Result := 0; + + else + Time_Out := + (if Rel_Time >= Duration (Time_Out_Max) / 1000 + then Time_Out_Max + else DWORD (Rel_Time * 1000)); + + Wait_Result := WaitForSingleObject (HANDLE (Cond.all), Time_Out); + + if Wait_Result = WAIT_TIMEOUT then + Timed_Out := True; + Wait_Result := 0; + else + Timed_Out := False; + end if; + end if; + + Write_Lock (L, Global_Lock => True); + + -- Ensure post-condition + + if Timed_Out then + Result := SetEvent (HANDLE (Cond.all)); + pragma Assert (Result = Win32.TRUE); + end if; + + Status := Integer (Wait_Result); + end Cond_Timed_Wait; + + ------------------ + -- 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, 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 is + Self_Id : constant Task_Id := To_Task_Id (TlsGetValue (TlsIndex)); + begin + if Self_Id = null then + return Register_Foreign_Thread (GetCurrentThread); + else + return Self_Id; + end if; + end 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 the RTS is initialized before any + -- status change of RTS. Therefore raising Storage_Error in the following + -- routines should be able to be handled safely. + + procedure Initialize_Lock + (Prio : System.Any_Priority; + L : not null access Lock) + is + begin + InitializeCriticalSection (L.Mutex'Access); + L.Owner_Priority := 0; + L.Priority := Prio; + end Initialize_Lock; + + procedure Initialize_Lock + (L : not null access RTS_Lock; Level : Lock_Level) + is + pragma Unreferenced (Level); + begin + InitializeCriticalSection (L); + end Initialize_Lock; + + ------------------- + -- Finalize_Lock -- + ------------------- + + procedure Finalize_Lock (L : not null access Lock) is + begin + DeleteCriticalSection (L.Mutex'Access); + end Finalize_Lock; + + procedure Finalize_Lock (L : not null access RTS_Lock) is + begin + DeleteCriticalSection (L); + end Finalize_Lock; + + ---------------- + -- Write_Lock -- + ---------------- + + procedure Write_Lock + (L : not null access Lock; Ceiling_Violation : out Boolean) is + begin + L.Owner_Priority := Get_Priority (Self); + + if L.Priority < L.Owner_Priority then + Ceiling_Violation := True; + return; + end if; + + EnterCriticalSection (L.Mutex'Access); + + Ceiling_Violation := False; + end Write_Lock; + + procedure Write_Lock + (L : not null access RTS_Lock; + Global_Lock : Boolean := False) + is + begin + if not Single_Lock or else Global_Lock then + EnterCriticalSection (L); + end if; + end Write_Lock; + + procedure Write_Lock (T : Task_Id) is + begin + if not Single_Lock then + EnterCriticalSection (T.Common.LL.L'Access); + end if; + end Write_Lock; + + --------------- + -- Read_Lock -- + --------------- + + procedure Read_Lock + (L : not null access Lock; Ceiling_Violation : out Boolean) is + begin + Write_Lock (L, Ceiling_Violation); + end Read_Lock; + + ------------ + -- Unlock -- + ------------ + + procedure Unlock (L : not null access Lock) is + begin + LeaveCriticalSection (L.Mutex'Access); + end Unlock; + + procedure Unlock + (L : not null access RTS_Lock; Global_Lock : Boolean := False) is + begin + if not Single_Lock or else Global_Lock then + LeaveCriticalSection (L); + end if; + end Unlock; + + procedure Unlock (T : Task_Id) is + begin + if not Single_Lock then + LeaveCriticalSection (T.Common.LL.L'Access); + end if; + end Unlock; + + ----------------- + -- Set_Ceiling -- + ----------------- + + -- Dynamic priority ceilings are not supported by the underlying system + + procedure Set_Ceiling + (L : not null access Lock; + Prio : System.Any_Priority) + is + pragma Unreferenced (L, Prio); + begin + null; + end Set_Ceiling; + + ----------- + -- Sleep -- + ----------- + + procedure Sleep + (Self_ID : Task_Id; + Reason : System.Tasking.Task_States) + is + pragma Unreferenced (Reason); + + begin + pragma Assert (Self_ID = Self); + + if Single_Lock then + Cond_Wait (Self_ID.Common.LL.CV'Access, Single_RTS_Lock'Access); + else + Cond_Wait (Self_ID.Common.LL.CV'Access, Self_ID.Common.LL.L'Access); + end if; + + 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 -- + ----------------- + + -- This is for use within the run-time system, so abort is assumed to be + -- already deferred, and the caller should be holding its own ATCB lock. + + 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); + Check_Time : Duration := Monotonic_Clock; + Rel_Time : Duration; + Abs_Time : Duration; + + Result : Integer; + pragma Unreferenced (Result); + + Local_Timedout : Boolean; + + begin + Timedout := True; + Yielded := False; + + if Mode = Relative then + Rel_Time := Time; + Abs_Time := Duration'Min (Time, Max_Sensible_Delay) + Check_Time; + else + Rel_Time := Time - Check_Time; + Abs_Time := Time; + end if; + + if Rel_Time > 0.0 then + loop + exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level; + + if Single_Lock then + Cond_Timed_Wait + (Self_ID.Common.LL.CV'Access, + Single_RTS_Lock'Access, + Rel_Time, Local_Timedout, Result); + else + Cond_Timed_Wait + (Self_ID.Common.LL.CV'Access, + Self_ID.Common.LL.L'Access, + Rel_Time, Local_Timedout, Result); + end if; + + Check_Time := Monotonic_Clock; + exit when Abs_Time <= Check_Time; + + if not Local_Timedout then + + -- Somebody may have called Wakeup for us + + Timedout := False; + exit; + end if; + + Rel_Time := Abs_Time - Check_Time; + end loop; + end if; + end Timed_Sleep; + + ----------------- + -- Timed_Delay -- + ----------------- + + procedure Timed_Delay + (Self_ID : Task_Id; + Time : Duration; + Mode : ST.Delay_Modes) + is + Check_Time : Duration := Monotonic_Clock; + Rel_Time : Duration; + Abs_Time : Duration; + + Timedout : Boolean; + Result : Integer; + pragma Unreferenced (Timedout, Result); + + begin + if Single_Lock then + Lock_RTS; + end if; + + Write_Lock (Self_ID); + + if Mode = Relative then + Rel_Time := Time; + Abs_Time := Time + Check_Time; + else + Rel_Time := Time - Check_Time; + Abs_Time := Time; + end if; + + if Rel_Time > 0.0 then + Self_ID.Common.State := Delay_Sleep; + + loop + exit when Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level; + + if Single_Lock then + Cond_Timed_Wait + (Self_ID.Common.LL.CV'Access, + Single_RTS_Lock'Access, + Rel_Time, Timedout, Result); + else + Cond_Timed_Wait + (Self_ID.Common.LL.CV'Access, + Self_ID.Common.LL.L'Access, + Rel_Time, Timedout, Result); + end if; + + Check_Time := Monotonic_Clock; + exit when Abs_Time <= Check_Time; + + Rel_Time := Abs_Time - Check_Time; + end loop; + + Self_ID.Common.State := Runnable; + end if; + + Unlock (Self_ID); + + if Single_Lock then + Unlock_RTS; + end if; + + Yield; + end Timed_Delay; + + ------------ + -- Wakeup -- + ------------ + + procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is + pragma Unreferenced (Reason); + begin + Cond_Signal (T.Common.LL.CV'Access); + end Wakeup; + + ----------- + -- Yield -- + ----------- + + procedure Yield (Do_Yield : Boolean := True) is + begin + -- Note: in a previous implementation if Do_Yield was False, then we + -- introduced a delay of 1 millisecond in an attempt to get closer to + -- annex D semantics, and in particular to make ACATS CXD8002 pass. But + -- this change introduced a huge performance regression evaluating the + -- Count attribute. So we decided to remove this processing. + + -- Moreover, CXD8002 appears to pass on Windows (although we do not + -- guarantee full Annex D compliance on Windows in any case). + + if Do_Yield then + SwitchToThread; + end if; + end Yield; + + ------------------ + -- Set_Priority -- + ------------------ + + procedure Set_Priority + (T : Task_Id; + Prio : System.Any_Priority; + Loss_Of_Inheritance : Boolean := False) + is + Res : BOOL; + pragma Unreferenced (Loss_Of_Inheritance); + + begin + Res := + SetThreadPriority + (T.Common.LL.Thread, + Interfaces.C.int (Underlying_Priorities (Prio))); + pragma Assert (Res = Win32.TRUE); + + -- Note: Annex D (RM D.2.3(5/2)) requires the task to be placed at the + -- head of its priority queue when decreasing its priority as a result + -- of a loss of inherited priority. This is not the case, but we + -- consider it an acceptable variation (RM 1.1.3(6)), given this is + -- the built-in behavior offered by the Windows operating system. + + -- In older versions we attempted to better approximate the Annex D + -- required behavior, but this simulation was not entirely accurate, + -- and it seems better to live with the standard Windows semantics. + + T.Common.Current_Priority := Prio; + 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 -- + ---------------- + + -- There were two paths were we needed to call Enter_Task : + -- 1) from System.Task_Primitives.Operations.Initialize + -- 2) from System.Tasking.Stages.Task_Wrapper + + -- The thread initialisation has to be done only for the first case + + -- This is because the GetCurrentThread NT call does not return the real + -- thread handler but only a "pseudo" one. It is not possible to release + -- the thread handle and free the system resources from this "pseudo" + -- handle. So we really want to keep the real thread handle set in + -- System.Task_Primitives.Operations.Create_Task during thread creation. + + procedure Enter_Task (Self_ID : Task_Id) is + procedure Get_Stack_Bounds (Base : Address; Limit : Address); + pragma Import (C, Get_Stack_Bounds, "__gnat_get_stack_bounds"); + -- Get stack boundaries + begin + Specific.Set (Self_ID); + + -- Properly initializes the FPU for x86 systems + + System.Float_Control.Reset; + + if Self_ID.Common.Task_Info /= null + and then + Self_ID.Common.Task_Info.CPU >= CPU_Number (Number_Of_Processors) + then + raise Invalid_CPU_Number; + end if; + + Self_ID.Common.LL.Thread_Id := GetCurrentThreadId; + + Get_Stack_Bounds + (Self_ID.Common.Compiler_Data.Pri_Stack_Info.Base'Address, + Self_ID.Common.Compiler_Data.Pri_Stack_Info.Limit'Address); + end Enter_Task; + + ------------------- + -- 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 (GetCurrentThread); + end if; + end Register_Foreign_Thread; + + -------------------- + -- Initialize_TCB -- + -------------------- + + procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is + begin + -- Initialize thread ID to 0, this is needed to detect threads that + -- are not yet activated. + + Self_ID.Common.LL.Thread := Null_Thread_Id; + + Initialize_Cond (Self_ID.Common.LL.CV'Access); + + if not Single_Lock then + Initialize_Lock (Self_ID.Common.LL.L'Access, ATCB_Level); + end if; + + Succeeded := True; + 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 + Initial_Stack_Size : constant := 1024; + -- We set the initial stack size to 1024. On Windows version prior to XP + -- there is no way to fix a task stack size. Only the initial stack size + -- can be set, the operating system will raise the task stack size if + -- needed. + + function Is_Windows_XP return Integer; + pragma Import (C, Is_Windows_XP, "__gnat_is_windows_xp"); + -- Returns 1 if running on Windows XP + + hTask : HANDLE; + TaskId : aliased DWORD; + pTaskParameter : Win32.PVOID; + Result : DWORD; + Entry_Point : PTHREAD_START_ROUTINE; + + use type System.Multiprocessors.CPU_Range; + + begin + -- Check whether both Dispatching_Domain and CPU are specified for the + -- task, and the CPU value is not contained within the range of + -- processors for the domain. + + if T.Common.Domain /= null + and then T.Common.Base_CPU /= System.Multiprocessors.Not_A_Specific_CPU + and then + (T.Common.Base_CPU not in T.Common.Domain'Range + or else not T.Common.Domain (T.Common.Base_CPU)) + then + Succeeded := False; + return; + end if; + + pTaskParameter := To_Address (T); + + Entry_Point := To_PTHREAD_START_ROUTINE (Wrapper); + + if Is_Windows_XP = 1 then + hTask := CreateThread + (null, + DWORD (Stack_Size), + Entry_Point, + pTaskParameter, + DWORD (Create_Suspended) or + DWORD (Stack_Size_Param_Is_A_Reservation), + TaskId'Unchecked_Access); + else + hTask := CreateThread + (null, + Initial_Stack_Size, + Entry_Point, + pTaskParameter, + DWORD (Create_Suspended), + TaskId'Unchecked_Access); + end if; + + -- Step 1: Create the thread in blocked mode + + if hTask = 0 then + Succeeded := False; + return; + end if; + + -- Step 2: set its TCB + + T.Common.LL.Thread := hTask; + + -- Note: it would be useful to initialize Thread_Id right away to avoid + -- a race condition in gdb where Thread_ID may not have the right value + -- yet, but GetThreadId is a Vista specific API, not available under XP: + -- T.Common.LL.Thread_Id := GetThreadId (hTask); so instead we set the + -- field to 0 to avoid having a random value. Thread_Id is initialized + -- in Enter_Task anyway. + + T.Common.LL.Thread_Id := 0; + + -- Step 3: set its priority (child has inherited priority from parent) + + Set_Priority (T, Priority); + + if Time_Slice_Val = 0 + or else Dispatching_Policy = 'F' + or else Get_Policy (Priority) = 'F' + then + -- Here we need Annex D semantics so we disable the NT priority + -- boost. A priority boost is temporarily given by the system to + -- a thread when it is taken out of a wait state. + + SetThreadPriorityBoost (hTask, DisablePriorityBoost => Win32.TRUE); + end if; + + -- Step 4: Handle pragma CPU and Task_Info + + Set_Task_Affinity (T); + + -- Step 5: Now, start it for good + + Result := ResumeThread (hTask); + pragma Assert (Result = 1); + + Succeeded := Result = 1; + end Create_Task; + + ------------------ + -- Finalize_TCB -- + ------------------ + + procedure Finalize_TCB (T : Task_Id) is + Succeeded : BOOL; + + begin + if not Single_Lock then + Finalize_Lock (T.Common.LL.L'Access); + end if; + + Finalize_Cond (T.Common.LL.CV'Access); + + if T.Known_Tasks_Index /= -1 then + Known_Tasks (T.Known_Tasks_Index) := null; + end if; + + if T.Common.LL.Thread /= 0 then + + -- This task has been activated. Close the thread handle. This + -- is needed to release system resources. + + Succeeded := CloseHandle (T.Common.LL.Thread); + pragma Assert (Succeeded = Win32.TRUE); + end if; + + ATCB_Allocation.Free_ATCB (T); + 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 + pragma Unreferenced (T); + begin + null; + end Abort_Task; + + ---------------------- + -- 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; + + ---------------- + -- Initialize -- + ---------------- + + procedure Initialize (Environment_Task : Task_Id) is + Discard : BOOL; + pragma Unreferenced (Discard); + + begin + Environment_Task_Id := Environment_Task; + OS_Primitives.Initialize; + Interrupt_Management.Initialize; + + if Time_Slice_Val = 0 or else Dispatching_Policy = 'F' then + -- Here we need Annex D semantics, switch the current process to the + -- Realtime_Priority_Class. + + Discard := OS_Interface.SetPriorityClass + (GetCurrentProcess, Realtime_Priority_Class); + end if; + + TlsIndex := TlsAlloc; + + -- Initialize the lock used to synchronize chain of all ATCBs + + Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level); + + Environment_Task.Common.LL.Thread := GetCurrentThread; + + -- Make environment task known here because it doesn't go through + -- Activate_Tasks, which does it for all other tasks. + + Known_Tasks (Known_Tasks'First) := Environment_Task; + Environment_Task.Known_Tasks_Index := Known_Tasks'First; + + Enter_Task (Environment_Task); + + -- pragma CPU and dispatching domains for the environment task + + Set_Task_Affinity (Environment_Task); + end Initialize; + + --------------------- + -- Monotonic_Clock -- + --------------------- + + function Monotonic_Clock return Duration + renames System.OS_Primitives.Monotonic_Clock; + + ------------------- + -- RT_Resolution -- + ------------------- + + function RT_Resolution return Duration is + begin + return 0.000_001; -- 1 micro-second + end RT_Resolution; + + ---------------- + -- Initialize -- + ---------------- + + procedure Initialize (S : in out Suspension_Object) is + begin + -- Initialize internal state. It is always initialized to False (ARM + -- D.10 par. 6). + + S.State := False; + S.Waiting := False; + + -- Initialize internal mutex + + InitializeCriticalSection (S.L'Access); + + -- Initialize internal condition variable + + S.CV := CreateEvent (null, Win32.TRUE, Win32.FALSE, Null_Ptr); + pragma Assert (S.CV /= 0); + end Initialize; + + -------------- + -- Finalize -- + -------------- + + procedure Finalize (S : in out Suspension_Object) is + Result : BOOL; + + begin + -- Destroy internal mutex + + DeleteCriticalSection (S.L'Access); + + -- Destroy internal condition variable + + Result := CloseHandle (S.CV); + pragma Assert (Result = Win32.TRUE); + 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 + begin + SSL.Abort_Defer.all; + + EnterCriticalSection (S.L'Access); + + S.State := False; + + LeaveCriticalSection (S.L'Access); + + SSL.Abort_Undefer.all; + end Set_False; + + -------------- + -- Set_True -- + -------------- + + procedure Set_True (S : in out Suspension_Object) is + Result : BOOL; + + begin + SSL.Abort_Defer.all; + + EnterCriticalSection (S.L'Access); + + -- 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 := SetEvent (S.CV); + pragma Assert (Result = Win32.TRUE); + + else + S.State := True; + end if; + + LeaveCriticalSection (S.L'Access); + + SSL.Abort_Undefer.all; + end Set_True; + + ------------------------ + -- Suspend_Until_True -- + ------------------------ + + procedure Suspend_Until_True (S : in out Suspension_Object) is + Result : DWORD; + Result_Bool : BOOL; + + begin + SSL.Abort_Defer.all; + + EnterCriticalSection (S.L'Access); + + 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). + + LeaveCriticalSection (S.L'Access); + + 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; + + LeaveCriticalSection (S.L'Access); + + SSL.Abort_Undefer.all; + + else + S.Waiting := True; + + -- Must reset CV BEFORE L is unlocked + + Result_Bool := ResetEvent (S.CV); + pragma Assert (Result_Bool = Win32.TRUE); + + LeaveCriticalSection (S.L'Access); + + SSL.Abort_Undefer.all; + + Result := WaitForSingleObject (S.CV, Wait_Infinite); + pragma Assert (Result = 0); + end if; + end if; + end Suspend_Until_True; + + ---------------- + -- Check_Exit -- + ---------------- + + -- Dummy versions, currently this only works for solaris (native) + + 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; + + ------------------ + -- Suspend_Task -- + ------------------ + + function Suspend_Task + (T : ST.Task_Id; + Thread_Self : Thread_Id) return Boolean + is + begin + if T.Common.LL.Thread /= Thread_Self then + return SuspendThread (T.Common.LL.Thread) = NO_ERROR; + else + return True; + end if; + end Suspend_Task; + + ----------------- + -- Resume_Task -- + ----------------- + + function Resume_Task + (T : ST.Task_Id; + Thread_Self : Thread_Id) return Boolean + is + begin + if T.Common.LL.Thread /= Thread_Self then + return ResumeThread (T.Common.LL.Thread) = NO_ERROR; + else + return True; + end if; + end Resume_Task; + + -------------------- + -- Stop_All_Tasks -- + -------------------- + + procedure Stop_All_Tasks is + begin + null; + end Stop_All_Tasks; + + --------------- + -- Stop_Task -- + --------------- + + function Stop_Task (T : ST.Task_Id) return Boolean is + pragma Unreferenced (T); + begin + return False; + end Stop_Task; + + ------------------- + -- Continue_Task -- + ------------------- + + function Continue_Task (T : ST.Task_Id) return Boolean is + pragma Unreferenced (T); + begin + return False; + end Continue_Task; + + ----------------------- + -- Set_Task_Affinity -- + ----------------------- + + procedure Set_Task_Affinity (T : ST.Task_Id) is + Result : DWORD; + + use type System.Multiprocessors.CPU_Range; + + begin + -- Do nothing if the underlying thread has not yet been created. If the + -- thread has not yet been created then the proper affinity will be set + -- during its creation. + + if T.Common.LL.Thread = Null_Thread_Id then + null; + + -- pragma CPU + + elsif T.Common.Base_CPU /= Multiprocessors.Not_A_Specific_CPU then + + -- The CPU numbering in pragma CPU starts at 1 while the subprogram + -- to set the affinity starts at 0, therefore we must substract 1. + + Result := + SetThreadIdealProcessor + (T.Common.LL.Thread, ProcessorId (T.Common.Base_CPU) - 1); + pragma Assert (Result = 1); + + -- Task_Info + + elsif T.Common.Task_Info /= null then + if T.Common.Task_Info.CPU /= Task_Info.Any_CPU then + Result := + SetThreadIdealProcessor + (T.Common.LL.Thread, T.Common.Task_Info.CPU); + pragma Assert (Result = 1); + end if; + + -- Dispatching domains + + elsif T.Common.Domain /= null + and then (T.Common.Domain /= ST.System_Domain + or else + T.Common.Domain.all /= + (Multiprocessors.CPU'First .. + Multiprocessors.Number_Of_CPUs => True)) + then + declare + CPU_Set : DWORD := 0; + + begin + for Proc in T.Common.Domain'Range loop + if T.Common.Domain (Proc) then + + -- The thread affinity mask is a bit vector in which each + -- bit represents a logical processor. + + CPU_Set := CPU_Set + 2 ** (Integer (Proc) - 1); + end if; + end loop; + + Result := SetThreadAffinityMask (T.Common.LL.Thread, CPU_Set); + pragma Assert (Result = 1); + end; + end if; + end Set_Task_Affinity; + +end System.Task_Primitives.Operations; |