-- --
-- 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 GNU/Linux (GNU/LinuxThreads) 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 Ada.Unchecked_Conversion;
+with Ada.Unchecked_Deallocation;
with Interfaces.C;
--- used for int
--- size_t
+with System.Task_Info;
+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
-
-with Ada.Exceptions;
--- used for Raise_Exception
--- Raise_From_Signal_Handler
--- Exception_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.OS_Primitives;
--- used for Delay_Modes
+with System.Stack_Checking.Operations;
with System.Soft_Links;
--- used for Get_Machine_State_Addr
-
-with Unchecked_Conversion;
-with Unchecked_Deallocation;
+-- 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;
+ package SC renames System.Stack_Checking.Operations;
+
use System.Tasking.Debug;
use System.Tasking;
use Interfaces.C;
use System.OS_Interface;
use System.Parameters;
use System.OS_Primitives;
+ use System.Task_Info;
- package SSL renames System.Soft_Links;
-
- ------------------
- -- Local Data --
- ------------------
+ ----------------
+ -- Local Data --
+ ----------------
-- The followings are logically constants, but need to be initialized
-- at run time.
-- 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
+ -- 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.
+ Environment_Task_Id : Task_Id;
+ -- 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
+ -- The set of signals that should be unblocked in all tasks
- -- The followings are internal configuration constants needed.
- Priority_Ceiling_Emulation : constant Boolean := True;
+ -- The followings are internal configuration constants needed
Next_Serial_Number : Task_Serial_Number := 100;
- -- We start at 100, to reserve some special values for
- -- using in error checking.
- -- The following are internal configuration constants needed.
+ -- We start at 100 (reserve some special values for using in error checks)
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");
- FIFO_Within_Priorities : constant Boolean := Dispatching_Policy = 'F';
- -- Indicates whether FIFO_Within_Priorities is set.
-
- -- The following are effectively constants, but they need to
- -- be initialized by calling a pthread_ function.
+ -- The following are effectively constants, but they need to be initialized
+ -- by calling a pthread_ function.
Mutex_Attr : aliased pthread_mutexattr_t;
Cond_Attr : aliased pthread_condattr_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)
+
+ Use_Alternate_Stack : constant Boolean := Alternate_Stack_Size /= 0;
+ -- Whether to use an alternate signal stack for stack overflows
+
+ Abort_Handler_Installed : Boolean := False;
+ -- True if a handler for the abort signal is installed
--------------------
-- Local Packages --
package Specific is
- procedure Initialize (Environment_Task : Task_ID);
+ 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);
-- Does executing thread have a TCB?
- procedure Set (Self_Id : Task_ID);
+ 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;
+ 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.
+ 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;
+ (Thread : Thread_Id) return Task_Id is separate;
-----------------------
-- Local Subprograms --
procedure Abort_Handler (signo : Signal);
- function To_pthread_t is new Unchecked_Conversion
+ function To_pthread_t is new Ada.Unchecked_Conversion
(unsigned_long, System.OS_Interface.pthread_t);
-------------------
procedure Abort_Handler (signo : Signal) is
pragma Unreferenced (signo);
- Self_Id : constant Task_ID := Self;
+ Self_Id : constant Task_Id := Self;
Result : Interfaces.C.int;
Old_Set : aliased sigset_t;
begin
+ -- 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;
-- 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;
-- The underlying thread system extends the memory (up to 2MB) when needed
- procedure Stack_Guard (T : ST.Task_ID; On : Boolean) is
+ procedure Stack_Guard (T : ST.Task_Id; On : Boolean) is
pragma Unreferenced (T);
pragma Unreferenced (On);
-
begin
null;
end Stack_Guard;
-- Get_Thread_Id --
--------------------
- function Get_Thread_Id (T : ST.Task_ID) return OSI.Thread_Id is
+ 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;
+ 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.
+ -- 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
+ pragma Unreferenced (Prio);
+
Result : Interfaces.C.int;
begin
- if Priority_Ceiling_Emulation then
- L.Ceiling := Prio;
- end if;
-
- Result := pthread_mutex_init (L.L'Access, Mutex_Attr'Access);
+ Result := pthread_mutex_init (L, Mutex_Attr'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
if Result = ENOMEM then
- Ada.Exceptions.Raise_Exception (Storage_Error'Identity,
- "Failed to allocate a lock");
+ raise Storage_Error with "Failed to allocate a lock";
end if;
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);
Result : Interfaces.C.int;
-- 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);
+ Result := pthread_mutex_destroy (L);
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);
pragma Assert (Result = 0);
-- 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;
-
begin
- if Priority_Ceiling_Emulation then
- declare
- Self_ID : constant Task_ID := Self;
-
- begin
- if Self_ID.Common.LL.Active_Priority > L.Ceiling then
- Ceiling_Violation := True;
- return;
- end if;
-
- L.Saved_Priority := Self_ID.Common.LL.Active_Priority;
-
- if Self_ID.Common.LL.Active_Priority < L.Ceiling then
- Self_ID.Common.LL.Active_Priority := L.Ceiling;
- end if;
-
- Result := pthread_mutex_lock (L.L'Access);
- pragma Assert (Result = 0);
- Ceiling_Violation := False;
- end;
-
- else
- Result := pthread_mutex_lock (L.L'Access);
- Ceiling_Violation := Result = EINVAL;
+ Result := pthread_mutex_lock (L);
+ Ceiling_Violation := Result = EINVAL;
- -- Assume the cause of EINVAL is a priority ceiling violation
+ -- Assume the cause of EINVAL is a priority ceiling violation
- pragma Assert (Result = 0 or else Result = EINVAL);
- end if;
+ pragma Assert (Result = 0 or else Result = EINVAL);
end Write_Lock;
procedure Write_Lock
- (L : access RTS_Lock;
+ (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
Result := pthread_mutex_lock (L);
end if;
end Write_Lock;
- procedure Write_Lock (T : Task_ID) is
+ 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);
-- 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
- if Priority_Ceiling_Emulation then
- declare
- Self_ID : constant Task_ID := Self;
-
- begin
- Result := pthread_mutex_unlock (L.L'Access);
- pragma Assert (Result = 0);
-
- if Self_ID.Common.LL.Active_Priority > L.Saved_Priority then
- Self_ID.Common.LL.Active_Priority := L.Saved_Priority;
- end if;
- end;
-
- else
- Result := pthread_mutex_unlock (L.L'Access);
- pragma Assert (Result = 0);
- end if;
+ Result := pthread_mutex_unlock (L);
+ 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
Result := pthread_mutex_unlock (L);
end if;
end Unlock;
- procedure Unlock (T : Task_ID) is
+ 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);
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;
+ (Self_ID : Task_Id;
Reason : System.Tasking.Task_States)
is
pragma Unreferenced (Reason);
begin
pragma Assert (Self_ID = Self);
- 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;
-- holding its own ATCB lock.
procedure Timed_Sleep
- (Self_ID : Task_ID;
+ (Self_ID : Task_Id;
Time : Duration;
Mode : ST.Delay_Modes;
Reason : System.Tasking.Task_States;
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);
+
+ Check_Time := Monotonic_Clock;
+ exit when Abs_Time <= Check_Time or else Check_Time < Base_Time;
- exit when Abs_Time <= Monotonic_Clock;
+ if Result = 0 or else Result = EINTR then
+
+ -- Somebody may have called Wakeup for us
- if Result = 0 or Result = EINTR then
- -- somebody may have called Wakeup for us
Timedout := False;
exit;
end if;
-- 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)
+ (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;
+ Result : Interfaces.C.int;
+ pragma Warnings (Off, Result);
+ begin
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
end if;
Result := sched_yield;
- SSL.Abort_Undefer.all;
end Timed_Delay;
---------------------
---------------------
function Monotonic_Clock return Duration is
- TV : aliased struct_timeval;
- Result : Interfaces.C.int;
+ use Interfaces;
+
+ type timeval is array (1 .. 2) of C.long;
+
+ procedure timeval_to_duration
+ (T : not null access timeval;
+ sec : not null access C.long;
+ usec : not null access C.long);
+ pragma Import (C, timeval_to_duration, "__gnat_timeval_to_duration");
+
+ Micro : constant := 10**6;
+ sec : aliased C.long;
+ usec : aliased C.long;
+ TV : aliased timeval;
+ Result : int;
+
+ function gettimeofday
+ (Tv : access timeval;
+ Tz : System.Address := System.Null_Address) return int;
+ pragma Import (C, gettimeofday, "gettimeofday");
begin
Result := gettimeofday (TV'Access, System.Null_Address);
pragma Assert (Result = 0);
- return To_Duration (TV);
+ timeval_to_duration (TV'Access, sec'Access, usec'Access);
+ return Duration (sec) + Duration (usec) / Micro;
end Monotonic_Clock;
-------------------
-- Wakeup --
------------
- procedure Wakeup (T : Task_ID; Reason : System.Tasking.Task_States) is
+ procedure Wakeup (T : Task_Id; Reason : System.Tasking.Task_States) is
pragma Unreferenced (Reason);
Result : Interfaces.C.int;
begin
------------------
procedure Set_Priority
- (T : Task_ID;
+ (T : Task_Id;
Prio : System.Any_Priority;
Loss_Of_Inheritance : Boolean := False)
is
Result : Interfaces.C.int;
Param : aliased struct_sched_param;
+ function Get_Policy (Prio : System.Any_Priority) return Character;
+ pragma Import (C, Get_Policy, "__gnat_get_specific_dispatching");
+ -- Get priority specific dispatching policy
+
+ 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;
- if Priority_Ceiling_Emulation then
- if T.Common.LL.Active_Priority < Prio then
- T.Common.LL.Active_Priority := Prio;
- end if;
- end if;
-
- -- Priorities are in range 1 .. 99 on GNU/Linux, so we map
- -- map 0 .. 31 to 1 .. 32
+ -- Priorities are 1 .. 99 on GNU/Linux, so we map 0 .. 98 to 1 .. 99
Param.sched_priority := Interfaces.C.int (Prio) + 1;
- 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
Param.sched_priority := 0;
- 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 or else Result = EPERM);
-- Get_Priority --
------------------
- function Get_Priority (T : Task_ID) return System.Any_Priority is
+ 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
+ procedure Enter_Task (Self_ID : Task_Id) is
begin
+ if Self_ID.Common.Task_Info /= null
+ and then Self_ID.Common.Task_Info.CPU_Affinity = No_CPU
+ then
+ raise Invalid_CPU_Number;
+ end if;
+
Self_ID.Common.LL.Thread := pthread_self;
+ Self_ID.Common.LL.LWP := lwp_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;
+ if Use_Alternate_Stack then
+ declare
+ Stack : aliased stack_t;
+ Result : Interfaces.C.int;
+ begin
+ Stack.ss_sp := Self_ID.Common.Task_Alternate_Stack;
+ Stack.ss_size := Alternate_Stack_Size;
+ Stack.ss_flags := 0;
+ Result := sigaltstack (Stack'Access, null);
+ pragma Assert (Result = 0);
+ end;
+ end if;
end Enter_Task;
--------------
-- New_ATCB --
--------------
- function New_ATCB (Entry_Num : Task_Entry_Index) return Task_ID is
+ function New_ATCB (Entry_Num : Task_Entry_Index) return Task_Id is
begin
return new Ada_Task_Control_Block (Entry_Num);
end New_ATCB;
-- Register_Foreign_Thread --
-----------------------------
- function Register_Foreign_Thread return Task_ID is
+ function Register_Foreign_Thread return Task_Id is
begin
if Is_Valid_Task then
return Self;
-- Initialize_TCB --
--------------------
- procedure Initialize_TCB (Self_ID : Task_ID; Succeeded : out Boolean) is
+ procedure Initialize_TCB (Self_ID : Task_Id; Succeeded : out Boolean) is
Result : Interfaces.C.int;
begin
- -- Give the task a unique serial number.
+ -- Give the task a unique serial number
Self_ID.Serial_Number := Next_Serial_Number;
Next_Serial_Number := Next_Serial_Number + 1;
-----------------
procedure Create_Task
- (T : Task_ID;
+ (T : Task_Id;
Wrapper : System.Address;
Stack_Size : System.Parameters.Size_Type;
Priority : System.Any_Priority;
Succeeded : out Boolean)
is
+ Attributes : aliased pthread_attr_t;
Adjusted_Stack_Size : Interfaces.C.size_t;
-
- Attributes : aliased pthread_attr_t;
- Result : Interfaces.C.int;
+ Result : Interfaces.C.int;
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);
-
- else
- Adjusted_Stack_Size := Interfaces.C.size_t (Stack_Size);
- end if;
+ Adjusted_Stack_Size :=
+ Interfaces.C.size_t (Stack_Size + Alternate_Stack_Size);
Result := pthread_attr_init (Attributes'Access);
pragma Assert (Result = 0 or else Result = ENOMEM);
Attributes'Access,
Thread_Body_Access (Wrapper),
To_Address (T));
- pragma Assert (Result = 0 or else Result = EAGAIN);
+ pragma Assert
+ (Result = 0 or else Result = EAGAIN or else Result = ENOMEM);
+
+ if Result /= 0 then
+ Succeeded := False;
+ Result := pthread_attr_destroy (Attributes'Access);
+ pragma Assert (Result = 0);
+ return;
+ end if;
+
+ Succeeded := True;
+
+ -- Handle Task_Info
- Succeeded := Result = 0;
+ if T.Common.Task_Info /= null then
+ if T.Common.Task_Info.CPU_Affinity /= Task_Info.Any_CPU then
+ Result :=
+ pthread_setaffinity_np
+ (T.Common.LL.Thread,
+ CPU_SETSIZE / 8,
+ T.Common.Task_Info.CPU_Affinity'Access);
+ pragma Assert (Result = 0);
+ end if;
+ end if;
Result := pthread_attr_destroy (Attributes'Access);
pragma Assert (Result = 0);
-- Finalize_TCB --
------------------
- procedure Finalize_TCB (T : Task_ID) is
+ procedure Finalize_TCB (T : Task_Id) is
Result : Interfaces.C.int;
- Tmp : Task_ID := T;
+ Tmp : Task_Id := T;
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
if T.Known_Tasks_Index /= -1 then
Known_Tasks (T.Known_Tasks_Index) := null;
end if;
-
+ SC.Invalidate_Stack_Cache (T.Common.Compiler_Data.Pri_Stack_Info'Access);
Free (Tmp);
if Is_Self then
-- Abort_Task --
----------------
- procedure Abort_Task (T : Task_ID) is
+ procedure Abort_Task (T : Task_Id) is
+ Result : Interfaces.C.int;
+ begin
+ if Abort_Handler_Installed then
+ Result :=
+ pthread_kill
+ (T.Common.LL.Thread,
+ Signal (System.Interrupt_Management.Abort_Task_Interrupt));
+ pragma Assert (Result = 0);
+ end if;
+ end Abort_Task;
+
+ ----------------
+ -- Initialize --
+ ----------------
+
+ procedure Initialize (S : in out Suspension_Object) is
Result : Interfaces.C.int;
begin
- Result := pthread_kill (T.Common.LL.Thread,
- Signal (System.Interrupt_Management.Abort_Task_Interrupt));
+ -- Initialize internal state (always to False (RM D.10(6)))
+
+ S.State := False;
+ S.Waiting := False;
+
+ -- Initialize internal mutex
+
+ Result := pthread_mutex_init (S.L'Access, Mutex_Attr'Access);
+
+ pragma Assert (Result = 0 or else Result = ENOMEM);
+
+ if Result = ENOMEM then
+ raise Storage_Error;
+ end if;
+
+ -- Initialize internal condition variable
+
+ 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);
- end Abort_Task;
+
+ -- Destroy internal condition variable
+
+ Result := pthread_cond_destroy (S.CV'Access);
+ pragma Assert (Result = 0);
+ end Finalize;
+
+ -------------------
+ -- Current_State --
+ -------------------
+
+ function Current_State (S : Suspension_Object) return Boolean is
+ begin
+ -- We do not want to use lock on this read operation. State is marked
+ -- as Atomic so that we ensure that the value retrieved is correct.
+
+ return S.State;
+ end Current_State;
+
+ ---------------
+ -- Set_False --
+ ---------------
+
+ procedure Set_False (S : in out Suspension_Object) is
+ Result : Interfaces.C.int;
+
+ begin
+ SSL.Abort_Defer.all;
+
+ Result := pthread_mutex_lock (S.L'Access);
+ pragma Assert (Result = 0);
+
+ S.State := False;
+
+ Result := pthread_mutex_unlock (S.L'Access);
+ pragma Assert (Result = 0);
+
+ SSL.Abort_Undefer.all;
+ end Set_False;
+
+ --------------
+ -- Set_True --
+ --------------
+
+ procedure Set_True (S : in out Suspension_Object) is
+ Result : Interfaces.C.int;
+
+ begin
+ SSL.Abort_Defer.all;
+
+ Result := pthread_mutex_lock (S.L'Access);
+ pragma Assert (Result = 0);
+
+ -- If there is already a task waiting on this suspension object then
+ -- we resume it, leaving the state of the suspension object to False,
+ -- as it is specified in ARM D.10 par. 9. Otherwise, it just leaves
+ -- the state to True.
+
+ if S.Waiting then
+ S.Waiting := False;
+ S.State := False;
+
+ Result := pthread_cond_signal (S.CV'Access);
+ pragma Assert (Result = 0);
+
+ else
+ S.State := True;
+ end if;
+
+ Result := pthread_mutex_unlock (S.L'Access);
+ pragma Assert (Result = 0);
+
+ SSL.Abort_Undefer.all;
+ end Set_True;
+
+ ------------------------
+ -- Suspend_Until_True --
+ ------------------------
+
+ procedure Suspend_Until_True (S : in out Suspension_Object) is
+ Result : Interfaces.C.int;
+
+ begin
+ SSL.Abort_Defer.all;
+
+ Result := pthread_mutex_lock (S.L'Access);
+ pragma Assert (Result = 0);
+
+ if S.Waiting then
+
+ -- Program_Error must be raised upon calling Suspend_Until_True
+ -- if another task is already waiting on that suspension object
+ -- (RM 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 (ARM D.10 par. 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). This should not
+ -- happen with the current Linux implementation of pthread, but
+ -- POSIX does not guarantee it so this may change in future.
+
+ 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 --
-- Dummy version
- function Check_Exit (Self_ID : ST.Task_ID) return Boolean is
+ 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
+ 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
+ function Environment_Task return Task_Id is
begin
- return Environment_Task_ID;
+ return Environment_Task_Id;
end Environment_Task;
------------------
------------------
function Suspend_Task
- (T : ST.Task_ID;
+ (T : ST.Task_Id;
Thread_Self : Thread_Id) return Boolean
is
begin
-----------------
function Resume_Task
- (T : ST.Task_ID;
+ (T : ST.Task_Id;
Thread_Self : Thread_Id) return Boolean
is
begin
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;
+
----------------
-- Initialize --
----------------
- procedure Initialize (Environment_Task : Task_ID) is
+ 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;
+ -- Whether to use an alternate signal stack for stack overflows
- function State (Int : System.Interrupt_Management.Interrupt_ID)
- return Character;
+ 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,
-- system handler)
begin
- Environment_Task_ID := Environment_Task;
+ Environment_Task_Id := Environment_Task;
+
+ Interrupt_Management.Initialize;
+
+ -- Prepare the set of signals that should be 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;
+
+ Result := pthread_mutexattr_init (Mutex_Attr'Access);
+ pragma Assert (Result = 0);
+
+ Result := pthread_condattr_init (Cond_Attr'Access);
+ pragma Assert (Result = 0);
Initialize_Lock (Single_RTS_Lock'Access, RTS_Lock_Level);
Specific.Initialize (Environment_Task);
- Enter_Task (Environment_Task);
+ if Use_Alternate_Stack then
+ Environment_Task.Common.Task_Alternate_Stack :=
+ Alternate_Stack'Address;
+ end if;
- -- Install the abort-signal handler
+ -- Make environment task known here because it doesn't go through
+ -- Activate_Tasks, which does it for all other tasks.
- if State (System.Interrupt_Management.Abort_Task_Interrupt)
- /= Default
+ 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
then
act.sa_flags := 0;
act.sa_handler := Abort_Handler'Address;
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;
-
- Result := pthread_mutexattr_init (Mutex_Attr'Access);
- pragma Assert (Result = 0);
-
- Result := pthread_condattr_init (Cond_Attr'Access);
- pragma Assert (Result = 0);
- end;
end System.Task_Primitives.Operations;
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