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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 Red Hat, 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.,

// 59 Temple Place, Suite 330, Boston, MA 02111-1307 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.

//

// This exception does not invalidate any other reasons why a work based on

// this file might be covered by the GNU General Public License.

//

// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.

// at http://sources.redhat.com/ecos/ecos-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 

//              ...

//              #include 

//              ...

//

//####DESCRIPTIONEND####

//

//==========================================================================

#include 

#include    // we use some thread inlines here

// -------------------------------------------------------------------------

// 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

inline void Cyg_SchedThread::remove()

{

    if( queue != NULL )

    {

        queue->remove((Cyg_Thread *)this);

        queue = NULL;

    }

}

// -------------------------------------------------------------------------

#endif // ifndef CYGONCE_KERNEL_SCHED_INL

// EOF sched.inl