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/*
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 * Project: S.Ha.R.K.
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 *
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 * Coordinators:
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 *   Giorgio Buttazzo    <giorgio@sssup.it>
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 *   Paolo Gai           <pj@gandalf.sssup.it>
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 *
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 * Authors     :
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 *   Paolo Gai           <pj@gandalf.sssup.it>
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 *   Massimiliano Giorgi <massy@gandalf.sssup.it>
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 *   Luca Abeni          <luca@gandalf.sssup.it>
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 *   (see the web pages for full authors list)
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 *
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 * ReTiS Lab (Scuola Superiore S.Anna - Pisa - Italy)
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 *
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 * http://www.sssup.it
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 * http://retis.sssup.it
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 * http://shark.sssup.it
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 */
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/**
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 ------------
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 CVS :        $Id: pi.h,v 1.3 2003-03-13 13:39:04 pj Exp $
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 File:        $File$
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 Revision:    $Revision: 1.3 $
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 Last update: $Date: 2003-03-13 13:39:04 $
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 ------------
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 This file contains the Priority Inheritance (PI) Protocol
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 Title:
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   PI (Priority Inheritance protocol)
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 Resource Models Accepted:
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   None
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 Description:
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   This module implement the Priority Inheritance Protocol.
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   The priority inheritance is made using the shadow field of the
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   task descriptor. No difference is made upon the task model of the
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   tasks that use PI mutexes.
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   A PI mutex is created passing the PI_mutexattr structure to mutex_init.
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 Exceptions raised:
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   XMUTEX_OWNER_KILLED
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     This exception is raised when a task ends and it owns one or more
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     mutexes
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 Restrictions & special features:
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   - This module is NOT Posix compliant
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   - This module can manage any number of PI mutexes.
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   - If a task ends (because it reaches the end of the body or because it
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     is killed by someone) and it owns some mutex, an exception is raised.
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   - if a mutex unlock is called on a mutex not previously
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     locked or previously locked by another task an exception is raised
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   - A PI mutex can be statically allocated. To do this, the init function
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     have to define a macro that puts this information in the mutex
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     descriptor: mutexlevel = <PI resource level>; opt = NULL;
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     for example, if the PI module is registered at level 1, the macro is
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     like:
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     #define MUTEX_INITIALIZER {1,NULL}
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**/
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/*
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 * Copyright (C) 2000 Paolo Gai
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License as published by
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 * the Free Software Foundation; either version 2 of the License, or
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 * (at your option) any later version.
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 *
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 * This program is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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 * GNU General Public License for more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 *
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 */
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#ifndef __PI_H__
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#define __PI_H__
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#include <kernel/types.h>
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#include "ll/sys/cdefs.h"
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__BEGIN_DECLS
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RLEVEL PI_register_module(void);
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__END_DECLS
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#endif