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#ifndef CYGONCE_KERNEL_SCHED_INL
#define CYGONCE_KERNEL_SCHED_INL
//==========================================================================
//
// sched.inl
//
// Scheduler class inlines
//
//==========================================================================
// ####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
//
// eCos 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 or (at your option) any later
// version.
//
// eCos 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 eCos; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// As a special exception, if other files instantiate templates or use
// macros or inline functions from this file, or you compile this file
// and link it with other works to produce a work based on this file,
// this file does not by itself cause the resulting work to be covered by
// the GNU General Public License. However the source code for this file
// must still be made available in accordance with section (3) of the GNU
// General Public License v2.
//
// This exception does not invalidate any other reasons why a work based
// on this file might be covered by the GNU General Public License.
// -------------------------------------------
// ####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s): nickg
// Contributors: nickg
// Date: 1997-09-09
// Purpose: Define inlines for scheduler classes
// Description: Inline functions for the scheduler classes. These are
// not defined in the header so that we have the option
// of making them non-inline.
// Usage:
// #include <cyg/kernel/sched.hxx>
// ...
// #include <cyg/kernel/sched.inl>
// ...
//
//####DESCRIPTIONEND####
//
//==========================================================================
#include <cyg/kernel/instrmnt.h>
#include <cyg/hal/hal_arch.h>
// -------------------------------------------------------------------------
// Inlines for Cyg_Scheduler class
inline void Cyg_Scheduler::lock()
{
// We do not need to do a read-modify-write sequence here because
// the scheduler lock is strictly nesting. Even if we are interrupted
// partway through the increment, the lock will be returned to the same
// value before we are resumed/rescheduled.
HAL_REORDER_BARRIER();
inc_sched_lock();
HAL_REORDER_BARRIER();
CYG_INSTRUMENT_SCHED(LOCK,get_sched_lock(),0);
};
inline void Cyg_Scheduler::unlock()
{
// This is an inline wrapper for the real scheduler unlock function in
// Cyg_Scheduler::unlock_inner().
// Only do anything if the lock is about to go zero, otherwise we simply
// decrement and return. As with lock() we do not need any special code
// to decrement the lock counter.
CYG_INSTRUMENT_SCHED(UNLOCK,get_sched_lock(),0);
HAL_REORDER_BARRIER();
cyg_ucount32 __lock = get_sched_lock() - 1;
if( __lock == 0 ) unlock_inner(0);
else set_sched_lock(__lock);
HAL_REORDER_BARRIER();
}
inline void Cyg_Scheduler::reschedule()
{
// This function performs the equivalent of calling unlock() and
// lock() is succession. Unlike that pair, however, it does not
// leave a brief window between the calls when the lock is unclaimed
// by the current thread.
CYG_INSTRUMENT_SCHED(RESCHEDULE,get_sched_lock(),0);
unlock_inner( get_sched_lock() );
}
inline void Cyg_Scheduler:: unlock_reschedule()
{
// This function decrements the scheduler lock and also looks for
// a reschedule opportunity. When the lock is being decremented
// from 1 to zero this function is equivalent to unlock. When the
// lock is being decremented to a non-zero value, it is more or less
// equivalent to reschedule() followed by unlock().
CYG_INSTRUMENT_SCHED(UNLOCK,get_sched_lock(),0);
unlock_inner( get_sched_lock() - 1 );
}
inline void Cyg_Scheduler::unlock_simple()
{
// This function decrements the lock, but does not call unlock_inner().
// Therefore does not immediately allow another thread to run:
// merely makes it possible for some other thread to run at some
// indeterminate future time. This is mainly for use by
// debuggers, it should not normally be used anywhere else.
CYG_INSTRUMENT_SCHED(UNLOCK,get_sched_lock(),0);
HAL_REORDER_BARRIER();
if (get_sched_lock() > 1)
set_sched_lock(get_sched_lock() - 1);
else zero_sched_lock();
HAL_REORDER_BARRIER();
}
// -------------------------------------------------------------------------
// Inlines for Cyg_SchedThread class
#include <cyg/kernel/thread.inl> // we use some thread inlines here
inline void Cyg_SchedThread::remove()
{
if( queue != NULL )
{
queue->remove((Cyg_Thread *)this);
queue = NULL;
}
}
// -------------------------------------------------------------------------
#endif // ifndef CYGONCE_KERNEL_SCHED_INL
// EOF sched.inl
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