| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT COMPILER COMPONENTS -- |
| -- -- |
| -- S Y S T E M . T A S K _ I N F O -- |
| -- -- |
| -- S p e c -- |
| -- -- |
| -- Copyright (C) 1992-2014, Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT 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/>. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This package contains the definitions and routines associated with the |
| -- implementation and use of the Task_Info pragma. It is specialized |
| -- appropriately for targets that make use of this pragma. |
| |
| -- Note: the compiler generates direct calls to this interface, via Rtsfind. |
| -- Any changes to this interface may require corresponding compiler changes. |
| |
| -- The functionality in this unit is now provided by the predefined package |
| -- System.Multiprocessors and the CPU aspect. This package is obsolescent. |
| |
| -- This is the Solaris (native) version of this module |
| |
| with System.OS_Interface; |
| |
| package System.Task_Info is |
| pragma Obsolescent (Task_Info, "use System.Multiprocessors and CPU aspect"); |
| pragma Preelaborate; |
| pragma Elaborate_Body; |
| -- To ensure that a body is allowed |
| |
| ----------------------------------------------------- |
| -- Binding of Tasks to LWPs and LWPs to processors -- |
| ----------------------------------------------------- |
| |
| -- The Solaris implementation of the GNU Low-Level Interface (GNULLI) |
| -- implements each Ada task as a Solaris thread. The Solaris thread |
| -- library distributes threads across one or more LWPs (Light Weight |
| -- Process) that are members of the same process. Solaris distributes |
| -- processes and LWPs across the available CPUs on a given machine. The |
| -- pragma Task_Info provides the mechanism to control the distribution |
| -- of tasks to LWPs, and LWPs to processors. |
| |
| -- Each thread has a number of attributes that dictate it's scheduling. |
| -- These attributes are: |
| -- |
| -- New_LWP: whether a new LWP is created for this thread. |
| -- |
| -- Bound_To_LWP: whether the thread is bound to a specific LWP |
| -- for its entire lifetime. |
| -- |
| -- CPU: the CPU number associated to the LWP |
| -- |
| |
| -- The Task_Info pragma: |
| |
| -- pragma Task_Info (EXPRESSION); |
| |
| -- allows the specification on a task by task basis of a value of type |
| -- System.Task_Info.Task_Info_Type to be passed to a task when it is |
| -- created. The specification of this type, and the effect on the task |
| -- that is created is target dependent. |
| |
| -- The Task_Info pragma appears within a task definition (compare the |
| -- definition and implementation of pragma Priority). If no such pragma |
| -- appears, then the value Unspecified_Task_Info is passed. If a pragma |
| -- is present, then it supplies an alternative value. If the argument of |
| -- the pragma is a discriminant reference, then the value can be set on |
| -- a task by task basis by supplying the appropriate discriminant value. |
| |
| -- Note that this means that the type used for Task_Info_Type must be |
| -- suitable for use as a discriminant (i.e. a scalar or access type). |
| |
| ----------------------- |
| -- Thread Attributes -- |
| ----------------------- |
| |
| subtype CPU_Number is System.OS_Interface.processorid_t; |
| |
| CPU_UNCHANGED : constant CPU_Number := System.OS_Interface.PBIND_QUERY; |
| -- Do not bind the LWP to a specific processor |
| |
| ANY_CPU : constant CPU_Number := System.OS_Interface.PBIND_NONE; |
| -- Bind the LWP to any processor |
| |
| Invalid_CPU_Number : exception; |
| |
| type Thread_Attributes (New_LWP : Boolean) is record |
| Bound_To_LWP : Boolean := True; |
| case New_LWP is |
| when False => |
| null; |
| when True => |
| CPU : CPU_Number := CPU_UNCHANGED; |
| end case; |
| end record; |
| |
| Default_Thread_Attributes : constant Thread_Attributes := (False, True); |
| |
| function Unbound_Thread_Attributes |
| return Thread_Attributes; |
| |
| function Bound_Thread_Attributes |
| return Thread_Attributes; |
| |
| function Bound_Thread_Attributes (CPU : CPU_Number) |
| return Thread_Attributes; |
| |
| type Task_Info_Type is access all Thread_Attributes; |
| |
| function New_Unbound_Thread_Attributes |
| return Task_Info_Type; |
| |
| function New_Bound_Thread_Attributes |
| return Task_Info_Type; |
| |
| function New_Bound_Thread_Attributes (CPU : CPU_Number) |
| return Task_Info_Type; |
| |
| Unspecified_Task_Info : constant Task_Info_Type := null; |
| |
| end System.Task_Info; |
