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-- --
-- --
-- S Y S T E M . T A S K _ I N F O --
-- --
-- S p e c --
-- --
-- Copyright (C) 2007-2021, 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 --
-- --
-- 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 --
-- <>. --
-- --
-- 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 GNU/Linux 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
-- The Linux kernel provides a way to define the ideal processor to use for
-- a given thread. The ideal processor is not necessarily the one that will
-- be used by the OS but the OS will always try to schedule this thread to
-- the specified processor if it is available.
-- 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_Set is System.OS_Interface.cpu_set_t;
Any_CPU : constant CPU_Set := (bits => (others => True));
No_CPU : constant CPU_Set := (bits => (others => False));
Invalid_CPU_Number : exception;
-- Raised when an invalid CPU mask has been specified
-- i.e. An empty CPU set
type Thread_Attributes is record
CPU_Affinity : aliased CPU_Set := Any_CPU;
end record;
Default_Thread_Attributes : constant Thread_Attributes := (others => <>);
type Task_Info_Type is access all Thread_Attributes;
Unspecified_Task_Info : constant Task_Info_Type := null;
function Number_Of_Processors return Positive;
-- Returns the number of processors on the running host
end System.Task_Info;