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/**
* @file
*
* @brief Compares Priorities of Threads
*
* @ingroup ScoreScheduler
*/
/*
* Copyright (C) 2011 Petr Benes.
* Copyright (C) 2011 On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/system.h>
#include <rtems/config.h>
#include <rtems/score/scheduleredf.h>
#include <rtems/score/watchdogimpl.h>
int _Scheduler_EDF_Priority_compare (
Priority_Control p1,
Priority_Control p2
)
{
Watchdog_Interval time = _Watchdog_Ticks_since_boot;
/*
* Reorder priorities to separate deadline driven and background tasks.
*
* The background tasks have p1 or p2 > SCHEDULER_EDF_PRIO_MSB.
* The deadline driven tasks need to have subtracted current time in order
* to see which deadline is closer wrt. current time.
*/
if (!(p1 & SCHEDULER_EDF_PRIO_MSB))
p1 = (p1 - time) & ~SCHEDULER_EDF_PRIO_MSB;
if (!(p2 & SCHEDULER_EDF_PRIO_MSB))
p2 = (p2 - time) & ~SCHEDULER_EDF_PRIO_MSB;
return ((p1<p2) - (p1>p2));
}
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