------------------------------------------------------------------------------
-- --
--- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
+-- 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) 1992-2004, Free Software Foundation, Inc. --
+-- Copyright (C) 1992-2009, 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- --
+-- 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. 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. --
+-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
--- 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. --
+-- 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 DEC Unix 4.0d version of this package
+-- This is a Tru64 version of this package
--- This package contains all the GNULL primitives that interface directly
--- with the underlying OS.
+-- 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.
+-- 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.Task_Info;
--- used for Task_Info_Type
+with Ada.Unchecked_Deallocation;
with Interfaces;
--- used for Shift_Left
-
with Interfaces.C;
--- used for int
--- size_t
+with System.Tasking.Debug;
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
--- ATCB components and types
-
-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.OS_Primitives;
--- used for Delay_Modes
+with System.Task_Info;
-with Unchecked_Deallocation;
+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 System.Tasking.Debug;
use System.Tasking;
use Interfaces.C;
use System.Parameters;
use System.OS_Primitives;
- package SSL renames System.Soft_Links;
-
----------------
-- Local Data --
----------------
-- 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.
+ -- A variable to hold Task_Id for the environment task
Unblocked_Signal_Mask : aliased sigset_t;
-- The set of signals that should unblocked in all tasks
Dispatching_Policy : Character;
pragma Import (C, Dispatching_Policy, "__gl_task_dispatching_policy");
- FIFO_Within_Priorities : constant Boolean := Dispatching_Policy = 'F';
- -- Indicates whether FIFO_Within_Priorities is set.
-
Curpid : pid_t;
Foreign_Task_Elaborated : aliased Boolean := True;
- -- Used to identified fake tasks (i.e., non-Ada Threads).
+ -- Used to identified fake tasks (i.e., non-Ada Threads)
+
+ Abort_Handler_Installed : Boolean := False;
+ -- True if a handler for the abort signal is installed
--------------------
-- Local Packages --
procedure Initialize (Environment_Task : Task_Id);
pragma Inline (Initialize);
- -- Initialize various data needed by this package.
+ -- Initialize various data needed by this package
function Is_Valid_Task return Boolean;
pragma Inline (Is_Valid_Task);
procedure Set (Self_Id : Task_Id);
pragma Inline (Set);
- -- Set the self id for the current task.
+ -- 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.
+ -- 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.
+ -- 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.
+ -- Allocate and initialize a new ATCB for the current Thread
function Register_Foreign_Thread
(Thread : Thread_Id) return Task_Id is separate;
-----------------------
procedure Abort_Handler (Sig : Signal);
- -- Signal handler used to implement asynchronous abortion.
+ -- Signal handler used to implement asynchronous abort
+
+ function Get_Policy (Prio : System.Any_Priority) return Character;
+ pragma Import (C, Get_Policy, "__gnat_get_specific_dispatching");
+ -- Get priority specific dispatching policy
-------------------
-- Abort_Handler --
pragma Unreferenced (Sig);
T : constant Task_Id := Self;
- Result : Interfaces.C.int;
Old_Set : aliased sigset_t;
+ Result : Interfaces.C.int;
+ pragma Warnings (Off, Result);
+
begin
- -- It is not safe to raise an exception when using ZCX and the GCC
- -- exception handling mechanism.
+ -- It's not safe to raise an exception when using GCC ZCX mechanism.
+ -- Note that we still need to install a signal handler, since in some
+ -- cases (e.g. shutdown of the Server_Task in System.Interrupts) we
+ -- need to send the Abort signal to a task.
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 and then
- not T.Aborting
+ and then T.Pending_ATC_Level < T.ATC_Nesting_Level
+ and then not T.Aborting
then
T.Aborting := True;
-- Make sure signals used for RTS internal purpose are unmasked
- Result := pthread_sigmask (SIG_UNBLOCK,
- Unblocked_Signal_Mask'Unchecked_Access, Old_Set'Unchecked_Access);
+ Result :=
+ pthread_sigmask
+ (SIG_UNBLOCK,
+ Unblocked_Signal_Mask'Access,
+ Old_Set'Access);
pragma Assert (Result = 0);
raise Standard'Abort_Signal;
-- Stack_Guard --
------------------
- -- The underlying thread system sets a guard page at the
- -- bottom of a thread stack, so nothing is needed.
+ -- 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 (T);
pragma Unreferenced (On);
-
begin
null;
end Stack_Guard;
-- 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.
+ -- 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 raising Storage_Error in the following
+ -- routines should be able to be handled safely.
procedure Initialize_Lock
(Prio : System.Any_Priority;
- L : access Lock)
+ L : not null access Lock)
is
Attributes : aliased pthread_mutexattr_t;
Result : Interfaces.C.int;
pragma Assert (Result = 0);
end Initialize_Lock;
- procedure Initialize_Lock (L : access RTS_Lock; Level : Lock_Level) is
+ procedure Initialize_Lock
+ (L : not null access RTS_Lock;
+ Level : Lock_Level)
+ is
pragma Unreferenced (Level);
Attributes : aliased pthread_mutexattr_t;
-- Finalize_Lock --
-------------------
- procedure Finalize_Lock (L : access Lock) is
+ procedure Finalize_Lock (L : not null 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
+ procedure Finalize_Lock (L : not null access RTS_Lock) is
Result : Interfaces.C.int;
begin
Result := pthread_mutex_destroy (L);
-- Write_Lock --
----------------
- procedure Write_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
+ procedure Write_Lock
+ (L : not null access Lock;
+ Ceiling_Violation : out Boolean)
+ is
Result : Interfaces.C.int;
Self_ID : Task_Id;
All_Tasks_Link : Task_Id;
Current_Prio : System.Any_Priority;
begin
- -- Perform ceiling checks only when this is the locking policy in use.
+ -- Perform ceiling checks only when this is the locking policy in use
if Locking_Policy = 'C' then
Self_ID := Self;
end Write_Lock;
procedure Write_Lock
- (L : access RTS_Lock; Global_Lock : Boolean := False)
+ (L : not null access RTS_Lock;
+ Global_Lock : Boolean := False)
is
Result : Interfaces.C.int;
begin
-- Read_Lock --
---------------
- procedure Read_Lock (L : access Lock; Ceiling_Violation : out Boolean) is
+ 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 : access Lock) is
+ procedure Unlock (L : not null 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
+ procedure Unlock
+ (L : not null access RTS_Lock;
+ Global_Lock : Boolean := False)
+ is
Result : Interfaces.C.int;
begin
if not Single_Lock or else Global_Lock then
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 --
-----------
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;
+ Result :=
+ pthread_cond_wait
+ (cond => Self_ID.Common.LL.CV'Access,
+ mutex => (if Single_Lock
+ then Single_RTS_Lock'Access
+ else Self_ID.Common.LL.L'Access));
- -- EINTR is not considered a failure.
+ -- EINTR is not considered a failure
pragma Assert (Result = 0 or else Result = EINTR);
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.
+ -- 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;
is
pragma Unreferenced (Reason);
- Check_Time : constant Duration := Monotonic_Clock;
+ Base_Time : constant Duration := Monotonic_Clock;
+ Check_Time : Duration := Base_Time;
Abs_Time : Duration;
Request : aliased timespec;
Result : Interfaces.C.int;
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;
+ Abs_Time :=
+ (if Mode = Relative
+ then Duration'Min (Time, Max_Sensible_Delay) + Check_Time
+ else Duration'Min (Check_Time + Max_Sensible_Delay, Time));
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 Self_ID.Pending_ATC_Level < Self_ID.ATC_Nesting_Level;
+
+ Result :=
+ pthread_cond_timedwait
+ (cond => Self_ID.Common.LL.CV'Access,
+ mutex => (if Single_Lock
+ then Single_RTS_Lock'Access
+ else Self_ID.Common.LL.L'Access),
+ abstime => Request'Access);
- exit when Abs_Time <= Monotonic_Clock;
+ Check_Time := Monotonic_Clock;
+ exit when Abs_Time <= Check_Time or else Check_Time < Base_Time;
if Result = 0 or Result = EINTR then
-- Timed_Delay --
-----------------
- -- This is for use in implementing delay statements, so
- -- we assume the caller is abort-deferred but is holding
- -- no locks.
+ -- 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;
+ Base_Time : constant Duration := Monotonic_Clock;
+ Check_Time : Duration := Base_Time;
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;
+ Abs_Time :=
+ (if Mode = Relative
+ then Time + Check_Time
+ else Duration'Min (Check_Time + Max_Sensible_Delay, Time));
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;
- 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;
+ Result :=
+ pthread_cond_timedwait
+ (cond => Self_ID.Common.LL.CV'Access,
+ mutex => (if Single_Lock
+ then Single_RTS_Lock'Access
+ else Self_ID.Common.LL.L'Access),
+ abstime => Request'Access);
- exit when Abs_Time <= Monotonic_Clock;
+ Check_Time := Monotonic_Clock;
+ exit when Abs_Time <= Check_Time or else Check_Time < Base_Time;
- pragma Assert (Result = 0 or else
- Result = ETIMEDOUT or else
- Result = EINTR);
+ pragma Assert (Result = 0 or else
+ Result = ETIMEDOUT or else
+ Result = EINTR);
end loop;
Self_ID.Common.State := Runnable;
end if;
Yield;
- SSL.Abort_Undefer.all;
end Timed_Delay;
---------------------
function Monotonic_Clock return Duration is
TS : aliased timespec;
Result : Interfaces.C.int;
-
begin
Result := clock_gettime (CLOCK_REALTIME, TS'Unchecked_Access);
pragma Assert (Result = 0);
function RT_Resolution return Duration is
begin
- return 1.0 / 1024.0; -- Clock on DEC Alpha ticks at 1024 Hz
+ -- Returned value must be an integral multiple of Duration'Small (1 ns)
+ -- The following is the best approximation of 1/1024. The clock on the
+ -- DEC Alpha ticks at 1024 Hz.
+
+ return 0.000_976_563;
end RT_Resolution;
------------
Result : Interfaces.C.int;
Param : aliased struct_sched_param;
+ Priority_Specific_Policy : constant Character := Get_Policy (Prio);
+ -- Upper case first character of the policy name corresponding to the
+ -- task as set by a Priority_Specific_Dispatching pragma.
+
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);
+ if Dispatching_Policy = 'R'
+ or else Priority_Specific_Policy = 'R'
+ or else Time_Slice_Val > 0
+ then
+ Result :=
+ pthread_setschedparam
+ (T.Common.LL.Thread, SCHED_RR, Param'Access);
- elsif FIFO_Within_Priorities or else Time_Slice_Val = 0 then
- Result := pthread_setschedparam
- (T.Common.LL.Thread, SCHED_FIFO, Param'Access);
+ elsif Dispatching_Policy = 'F'
+ or else Priority_Specific_Policy = 'F'
+ or else Time_Slice_Val = 0
+ then
+ Result :=
+ pthread_setschedparam
+ (T.Common.LL.Thread, SCHED_FIFO, Param'Access);
else
- Result := pthread_setschedparam
- (T.Common.LL.Thread, SCHED_OTHER, Param'Access);
+ Result :=
+ pthread_setschedparam
+ (T.Common.LL.Thread, SCHED_OTHER, Param'Access);
end if;
pragma Assert (Result = 0);
procedure Enter_Task (Self_ID : Task_Id) is
begin
+ Hide_Unhide_Yellow_Zone (Hide => True);
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;
+ Specific.Set (Self_ID);
end Enter_Task;
--------------
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);
+ Result :=
+ pthread_mutex_init
+ (Self_ID.Common.LL.L'Access, Mutex_Attr'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
end if;
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);
+ Result :=
+ pthread_cond_init
+ (Self_ID.Common.LL.CV'Access, Cond_Attr'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
end if;
Result : Interfaces.C.int;
Param : aliased System.OS_Interface.struct_sched_param;
+ Priority_Specific_Policy : constant Character := Get_Policy (Priority);
+ -- Upper case first character of the policy name corresponding to the
+ -- task as set by a Priority_Specific_Dispatching pragma.
+
use System.Task_Info;
begin
- if Stack_Size = Unspecified_Size then
- Adjusted_Stack_Size := Interfaces.C.size_t (Default_Stack_Size);
-
- elsif Stack_Size < Minimum_Stack_Size then
- Adjusted_Stack_Size := Interfaces.C.size_t (Minimum_Stack_Size);
+ -- Account for the Yellow Zone (2 pages) and the guard page right above.
+ -- See Hide_Unhide_Yellow_Zone for the rationale.
- else
- Adjusted_Stack_Size := Interfaces.C.size_t (Stack_Size);
- end if;
+ Adjusted_Stack_Size :=
+ Interfaces.C.size_t (Stack_Size) + 3 * Get_Page_Size;
Result := pthread_attr_init (Attributes'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
return;
end if;
- Result := pthread_attr_setdetachstate
- (Attributes'Access, PTHREAD_CREATE_DETACHED);
+ Result :=
+ pthread_attr_setdetachstate
+ (Attributes'Access, PTHREAD_CREATE_DETACHED);
pragma Assert (Result = 0);
- Result := pthread_attr_setstacksize
- (Attributes'Access, Adjusted_Stack_Size);
+ Result :=
+ pthread_attr_setstacksize
+ (Attributes'Access, Adjusted_Stack_Size);
pragma Assert (Result = 0);
Param.sched_priority :=
Interfaces.C.int (Underlying_Priorities (Priority));
- Result := pthread_attr_setschedparam
- (Attributes'Access, Param'Access);
+ Result :=
+ pthread_attr_setschedparam
+ (Attributes'Access, Param'Access);
pragma Assert (Result = 0);
- if Time_Slice_Val > 0 then
- Result := pthread_attr_setschedpolicy
- (Attributes'Access, System.OS_Interface.SCHED_RR);
+ if Dispatching_Policy = 'R'
+ or else Priority_Specific_Policy = 'R'
+ or else Time_Slice_Val > 0
+ then
+ Result :=
+ pthread_attr_setschedpolicy
+ (Attributes'Access, System.OS_Interface.SCHED_RR);
- elsif FIFO_Within_Priorities or else Time_Slice_Val = 0 then
- Result := pthread_attr_setschedpolicy
- (Attributes'Access, System.OS_Interface.SCHED_FIFO);
+ elsif Dispatching_Policy = 'F'
+ or else Priority_Specific_Policy = 'F'
+ or else Time_Slice_Val = 0
+ then
+ Result :=
+ pthread_attr_setschedpolicy
+ (Attributes'Access, System.OS_Interface.SCHED_FIFO);
else
- Result := pthread_attr_setschedpolicy
- (Attributes'Access, System.OS_Interface.SCHED_OTHER);
+ Result :=
+ pthread_attr_setschedpolicy
+ (Attributes'Access, System.OS_Interface.SCHED_OTHER);
end if;
pragma Assert (Result = 0);
- -- Set the scheduling parameters explicitly, since this is the
- -- only way to force the OS to take e.g. the sched policy and scope
- -- attributes into account.
+ -- Set the scheduling parameters explicitly, since this is the only way
+ -- to force the OS to take e.g. the sched policy and scope attributes
+ -- into account.
- Result := pthread_attr_setinheritsched
- (Attributes'Access, PTHREAD_EXPLICIT_SCHED);
+ Result :=
+ pthread_attr_setinheritsched
+ (Attributes'Access, PTHREAD_EXPLICIT_SCHED);
pragma Assert (Result = 0);
T.Common.Current_Priority := Priority;
if T.Common.Task_Info /= null then
case T.Common.Task_Info.Contention_Scope is
when System.Task_Info.Process_Scope =>
- Result := pthread_attr_setscope
- (Attributes'Access, PTHREAD_SCOPE_PROCESS);
+ Result :=
+ pthread_attr_setscope
+ (Attributes'Access, PTHREAD_SCOPE_PROCESS);
when System.Task_Info.System_Scope =>
- Result := pthread_attr_setscope
- (Attributes'Access, PTHREAD_SCOPE_SYSTEM);
+ Result :=
+ pthread_attr_setscope
+ (Attributes'Access, PTHREAD_SCOPE_SYSTEM);
when System.Task_Info.Default_Scope =>
Result := 0;
-- 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));
+ Result :=
+ pthread_create
+ (T.Common.LL.Thread'Access,
+ Attributes'Access,
+ Thread_Body_Access (Wrapper),
+ To_Address (T));
pragma Assert (Result = 0 or else Result = EAGAIN);
Succeeded := Result = 0;
Result := pthread_attr_destroy (Attributes'Access);
pragma Assert (Result = 0);
- if T.Common.Task_Info /= null then
+ if Succeeded and then T.Common.Task_Info /= null then
+
-- ??? We're using a process-wide function to implement a task
-- specific characteristic.
if T.Common.Task_Info.Bind_To_Cpu_Number = 0 then
Result := bind_to_cpu (Curpid, 0);
+
elsif T.Common.Task_Info.Bind_To_Cpu_Number > 0 then
- Result := bind_to_cpu
- (Curpid,
- Interfaces.C.unsigned_long (
- Interfaces.Shift_Left
- (Interfaces.Unsigned_64'(1),
- T.Common.Task_Info.Bind_To_Cpu_Number - 1)));
+ Result :=
+ bind_to_cpu
+ (Curpid,
+ Interfaces.C.unsigned_long (
+ Interfaces.Shift_Left
+ (Interfaces.Unsigned_64'(1),
+ T.Common.Task_Info.Bind_To_Cpu_Number - 1)));
pragma Assert (Result = 0);
end if;
end if;
Is_Self : constant Boolean := T = Self;
procedure Free is new
- Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id);
+ Ada.Unchecked_Deallocation (Ada_Task_Control_Block, Task_Id);
begin
if not Single_Lock then
procedure Exit_Task is
begin
Specific.Set (null);
+ Hide_Unhide_Yellow_Zone (Hide => False);
end Exit_Task;
----------------
procedure Abort_Task (T : Task_Id) is
Result : Interfaces.C.int;
begin
- Result :=
- pthread_kill
- (T.Common.LL.Thread,
+ if Abort_Handler_Installed then
+ Result := pthread_kill (T.Common.LL.Thread,
Signal (System.Interrupt_Management.Abort_Task_Interrupt));
- pragma Assert (Result = 0);
+ pragma Assert (Result = 0);
+ 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 (always to False (RM D.10(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);
+ 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);
+
+ 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
+ raise Storage_Error;
+ end if;
+ end if;
+ 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
+ -- specified in (RM D.10(9)). Otherwise, leave the state set 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
+ -- (AM D.10(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 (RM D.10(9)).
+
+ if S.State then
+ S.State := False;
+ else
+ S.Waiting := True;
+
+ loop
+ -- Loop in case pthread_cond_wait returns earlier than expected
+ -- (e.g. in case of EINTR caused by a signal).
+
+ Result := pthread_cond_wait (S.CV'Access, S.L'Access);
+ pragma Assert (Result = 0 or else Result = EINTR);
+
+ exit when not S.Waiting;
+ end loop;
+ 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 --
----------------
function Check_Exit (Self_ID : ST.Task_Id) return Boolean is
pragma Unreferenced (Self_ID);
-
begin
return True;
end Check_Exit;
function Check_No_Locks (Self_ID : ST.Task_Id) return Boolean is
pragma Unreferenced (Self_ID);
-
begin
return True;
end Check_No_Locks;
(T : ST.Task_Id;
Thread_Self : Thread_Id) return Boolean
is
- pragma Warnings (Off, T);
- pragma Warnings (Off, Thread_Self);
-
+ pragma Unreferenced (T, Thread_Self);
begin
return False;
end Suspend_Task;
(T : ST.Task_Id;
Thread_Self : Thread_Id) return Boolean
is
- pragma Warnings (Off, T);
- pragma Warnings (Off, Thread_Self);
-
+ pragma Unreferenced (T, Thread_Self);
begin
return False;
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;
+
----------------
-- Initialize --
----------------
begin
Environment_Task_Id := Environment_Task;
- -- Initialize the lock used to synchronize chain of all ATCBs.
+ Interrupt_Management.Initialize;
+
+ -- 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;
+
+ Curpid := getpid;
+
+ -- 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);
+ -- Make environment task known here because it doesn't go through
+ -- Activate_Tasks, which does it for all other tasks.
- -- Install the abort-signal handler
+ Known_Tasks (Known_Tasks'First) := Environment_Task;
+ Environment_Task.Known_Tasks_Index := Known_Tasks'First;
+
+ Enter_Task (Environment_Task);
- if State (System.Interrupt_Management.Abort_Task_Interrupt)
- /= Default
+ if State
+ (System.Interrupt_Management.Abort_Task_Interrupt) /= Default
then
act.sa_flags := 0;
act.sa_handler := Abort_Handler'Address;
Result :=
sigaction
- (Signal (System.Interrupt_Management.Abort_Task_Interrupt),
- act'Unchecked_Access,
- old_act'Unchecked_Access);
+ (Signal (System.Interrupt_Management.Abort_Task_Interrupt),
+ act'Unchecked_Access,
+ old_act'Unchecked_Access);
pragma Assert (Result = 0);
+ Abort_Handler_Installed := True;
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;
- end;
-
- Curpid := getpid;
end System.Task_Primitives.Operations;
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