------------------------------------------------------------------------------ ------------------------------------------------------------------------------ -- Cheddar is a GNU GPL real-time scheduling analysis tool. -- This program provides services to automatically check schedulability and -- other performance criteria of real-time architecture models. -- -- Copyright (C) 2002-2016, Frank Singhoff, Alain Plantec, Jerome Legrand -- -- The Cheddar project was started in 2002 by -- Frank Singhoff, Lab-STICC UMR 6285 laboratory, Université de Bretagne Occidentale -- -- Cheddar has been published in the "Agence de Protection des Programmes/France" in 2008. -- Since 2008, Ellidiss technologies also contributes to the development of -- Cheddar and provides industrial support. -- -- The full list of contributors and sponsors can be found in AUTHORS.txt and SPONSORS.txt -- -- This program is free software; you can redistribute it and/or modify -- it under the terms of the GNU General Public License as published by -- the Free Software Foundation; either version 2 of the License, or -- (at your option) any later version. -- -- This program is distributed in the hope that it will be useful, -- but WITHOUT 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 -- along with this program; if not, write to the Free Software -- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA -- -- -- Contact : cheddar@listes.univ-brest.fr -- ------------------------------------------------------------------------------ -- Last update : -- $Rev: 1249 $ -- $Date: 2014-08-28 07:02:15 +0200 (Fri, 28 Aug 2014) $ -- $Author: singhoff $ ------------------------------------------------------------------------------ ------------------------------------------------------------------------------ with unbounded_strings; use unbounded_strings; package Scheduler.Fixed_Priority is type Fixed_Priority_Scheduler is abstract new Generic_Scheduler with private; type Fixed_Priority_Scheduler_Ptr is access all Fixed_Priority_Scheduler' Class; type Fixed_Priority_Tcb is new Tcb with record -- With fixed priority, task priority may change due to resource accesses -- This attribute stores the current task priorities taking care of resource accesses Current_Priority : Priority_Range; -- Store if a task is allowed to run because of its resource access requirement, i.e. does -- the task would be blocked now due to lock resources ?? Is_Resource_Ready : Boolean; end record; type Fixed_Priority_Tcb_Ptr is access all Fixed_Priority_Tcb'Class; procedure Initialize (A_Tcb : in out Fixed_Priority_Tcb); ---------------------------------------- type Fixed_Priority_Resource is new Shared_Resource with record Priority_Ceiling : Priority_Range; end record; type Fixed_Priority_Resource_Ptr is access all Fixed_Priority_Resource' Class; -------------------------------------------------------------------------------------------------------------------------------------------- -- This text is a summary of the blocking and priority inheritance implemented in this package -------------------------------------------------------------------------------------------------------------------------------------------- -- Protocol | Conditions to allocate | action when requesting | action on allocate | action on release -- | | task is blocked on | | -- | | allocation request | | -------------------------------------------------------------------------------------------------------------------------------------------- -- no_protocol | resource.state>0 | | resource.state-- | resource.state++ -------------------------------------------------------------------------------------------------------------------------------------------- -- PIP | | task in critical section | | task leaving -- | | inherits requesting task | | resource -- | | priority | | gets its initial priority -- | resource.state>0 | | resource.state-- | resource.state++ -------------------------------------------------------------------------------------------------------------------------------------------- -- IPCP | resource.state>0 | | resource.state-- | resource.state++ -- | | | | -- | | | requestion task priority = max (static priority, -- | | | ceiling priority of all allocated resources) -------------------------------------------------------------------------------------------------------------------------------------------- -- PCP | resource.state>0 AND | task in critical section | | task leaving -- | priority of requesting task is | inherits requesting task | | resource -- | greater than all priority ceiling| priority | | gets its initial priority -- | of resource that are allocated | | | -- | by other tasks | | | -- | | | resource.state-- | resource.state++ -------------------------------------------------------------------------------------------------------------------------------------------- function Build_Resource (My_Scheduler : in Fixed_Priority_Scheduler; A_Resource : Generic_Resource_Ptr) return Shared_Resource_Ptr; function Build_Tcb (My_Scheduler : in Fixed_Priority_Scheduler; A_Task : Generic_Task_Ptr) return Tcb_Ptr; procedure Do_Election (My_Scheduler : in out Fixed_Priority_Scheduler; Si : in out Scheduling_Information; Result : in out Scheduling_Sequence_Ptr; Msg : in out Unbounded_String; Current_Time : in Natural; Processor_Name : in Unbounded_String; Address_Space_Name : in Unbounded_String; My_Dependencies : in Tasks_Dependencies_Ptr; With_Offsets : Boolean; With_Precedencies : Boolean; With_Resources : Boolean; With_jitters : in Boolean; With_minimize_preemption : in Boolean; Event_To_Generate : in Time_Unit_Event_Type_Boolean_Table; Elected : in out Tasks_Range; No_Task : in out Boolean); procedure Check_Resource (My_Scheduler : in out Fixed_Priority_Scheduler; Si : in out Scheduling_Information; Result : in out Scheduling_Sequence_Ptr; Current_Time : in Natural; A_Tcb : in Tcb_Ptr; Is_Ready : out Boolean; Event_To_Generate : in Time_Unit_Event_Type_Boolean_Table); procedure Allocate_Resource (My_Scheduler : in out Fixed_Priority_Scheduler; Si : in out Scheduling_Information; Result : in out Scheduling_Sequence_Ptr; Current_Time : in Natural; A_Tcb : Tcb_Ptr; Event_To_Generate : in Time_Unit_Event_Type_Boolean_Table); procedure Release_Resource (My_Scheduler : in out Fixed_Priority_Scheduler; Si : in out Scheduling_Information; Result : in out Scheduling_Sequence_Ptr; Current_Time : in Natural; A_Tcb : Tcb_Ptr; Event_To_Generate : in Time_Unit_Event_Type_Boolean_Table); procedure Specific_Scheduler_Initialization (My_Scheduler : in out Fixed_Priority_Scheduler; Si : in out Scheduling_Information; Processor_Name : in Unbounded_String; address_space_name : in Unbounded_String; My_Tasks : in out Tasks_Set; my_schedulers : in Scheduler_table; My_Resources : in out Resources_Set; My_Buffers : in out Buffers_Set; My_Messages : in Messages_Set; Msg : in out Unbounded_String); procedure Compute_Ceiling_Of_Resources (My_Scheduler : in out Fixed_Priority_Scheduler; Si : in out Scheduling_Information; Processor_Name : in Unbounded_String; Address_space_Name : in Unbounded_String; My_Tasks : in out Tasks_Set; My_Resources : in out Resources_Set); procedure Dispatched_Change_Current_Priority (My_Scheduler : in out Fixed_Priority_Scheduler; A_Tcb : in Fixed_Priority_Tcb_Ptr; New_Priority : Priority_Range); procedure Change_Current_Priority (My_Scheduler : in out Fixed_Priority_Scheduler'Class; A_Tcb : in Fixed_Priority_Tcb_Ptr; New_Priority : Priority_Range); function Produce_Running_Task_Event (My_Scheduler : in Fixed_Priority_Scheduler; A_Task : in Tcb_Ptr) return Time_Unit_Event_Ptr; function Export_Xml_Event_Running_Task (My_Scheduler : in Fixed_Priority_Scheduler; An_Event : in Time_Unit_Event_Ptr) return Unbounded_String; private type Fixed_Priority_Scheduler is abstract new Generic_Scheduler with record Used_Resource : Boolean := False; end record; end Scheduler.Fixed_Priority;