Subversion Repositories or1k

#ifndef CYGONCE_MEMALLOC_MEMPOLT2_INL

#define CYGONCE_MEMALLOC_MEMPOLT2_INL

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

//

//      mempolt2.inl

//

//      Mempolt2 (Memory pool template) class declarations

//

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

//####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):    hmt

// Contributors: jlarmour

// Date:         2000-06-12

// Purpose:      Define Mempolt2 class interface

// Description:  The class defined here provides the APIs for thread-safe,

//               kernel-savvy memory managers; make a class with the

//               underlying allocator as the template parameter.

// Usage:        #include 

//

//

//####DESCRIPTIONEND####

//

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

#include     // assertion support

#include    // tracing support

#include   // implementation eg. Cyg_Thread::self();

#include    // implementation eg. Cyg_Scheduler::lock();

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

// Constructor; we _require_ these arguments and just pass them through to

// the implementation memory pool in use.

template 

Cyg_Mempolt2::Cyg_Mempolt2(

    cyg_uint8 *base,

    cyg_int32 size,

    CYG_ADDRWORD arg_thru)              // Constructor

    : pool( base, size, arg_thru )

{

}

template 

Cyg_Mempolt2::~Cyg_Mempolt2()  // destructor

{

    // Prevent preemption

    Cyg_Scheduler::lock();

    while ( ! queue.empty() ) {

        Cyg_Thread *thread = queue.dequeue();

        thread->set_wake_reason( Cyg_Thread::DESTRUCT );

        thread->wake();

    }

    // Unlock the scheduler and maybe switch threads

    Cyg_Scheduler::unlock();

}

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

// get some memory; wait if none available

template 

inline cyg_uint8 *

Cyg_Mempolt2::alloc( cyg_int32 size )

{

    CYG_REPORT_FUNCTION();

    // Prevent preemption

    Cyg_Scheduler::lock();

    CYG_ASSERTCLASS( this, "Bad this pointer");

    cyg_uint8 *ret;

    ret = pool.try_alloc( size );

    if ( ret ) {

        Cyg_Scheduler::unlock();

        CYG_ASSERTCLASS( this, "Bad this pointer");

        CYG_REPORT_RETVAL( ret );

        return ret;

    }

    Cyg_Thread *self = Cyg_Thread::self();

    Mempolt2WaitInfo waitinfo( size );

    self->set_wait_info( (CYG_ADDRWORD)&waitinfo );

    self->set_sleep_reason( Cyg_Thread::WAIT );

    self->sleep();

    queue.enqueue( self );

    CYG_ASSERT( 1 == Cyg_Scheduler::get_sched_lock(),

                "Called with non-zero scheduler lock");

    // Unlock scheduler and allow other threads to run

    Cyg_Scheduler::unlock();

    cyg_bool result = true; // just used as a flag here

    switch( self->get_wake_reason() )

    {

    case Cyg_Thread::DESTRUCT:

    case Cyg_Thread::BREAK:

        result = false;

        break;

    case Cyg_Thread::EXIT:

        self->exit();

        break;

    default:

        break;

    }

    if ( ! result )

        ret = NULL;

    else

        ret = waitinfo.addr;

    CYG_ASSERT( (!result) || (NULL != ret), "Good result but no alloc!" );

    CYG_ASSERTCLASS( this, "Bad this pointer");

    CYG_REPORT_RETVAL( ret );

    return ret;

}

#ifdef CYGFUN_KERNEL_THREADS_TIMER

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

// get some memory with a timeout

template 

inline cyg_uint8 *

Cyg_Mempolt2::alloc( cyg_int32 size, cyg_tick_count abs_timeout )

{

    CYG_REPORT_FUNCTION();

    // Prevent preemption

    Cyg_Scheduler::lock();

    CYG_ASSERTCLASS( this, "Bad this pointer");

    cyg_uint8 *ret;

    ret = pool.try_alloc( size );

    if ( ret ) {

        Cyg_Scheduler::unlock();

        CYG_ASSERTCLASS( this, "Bad this pointer");

        CYG_REPORT_RETVAL( ret );

        return ret;

    }

    Cyg_Thread *self = Cyg_Thread::self();

    Mempolt2WaitInfo waitinfo( size );

    self->set_timer( abs_timeout, Cyg_Thread::TIMEOUT );

    // If the timeout is in the past, the wake reason will have been set to

    // something other than NONE already. If so, skip the wait and go

    // straight to unlock.

    if( Cyg_Thread::NONE == self->get_wake_reason() ) {

        self->set_wait_info( (CYG_ADDRWORD)&waitinfo );

        self->sleep();

        queue.enqueue( self );

    }

    CYG_ASSERT( 1 == Cyg_Scheduler::get_sched_lock(),

                "Called with non-zero scheduler lock");

    // Unlock scheduler and allow other threads to run

    Cyg_Scheduler::unlock();

    // clear the timer; if it actually fired, no worries.

    self->clear_timer();

    cyg_bool result = true; // just used as a flag here

    switch( self->get_wake_reason() )

    {

    case Cyg_Thread::TIMEOUT:

        result = false;

        break;

    case Cyg_Thread::DESTRUCT:

    case Cyg_Thread::BREAK:

        result = false;

        break;

    case Cyg_Thread::EXIT:

        self->exit();

        break;

    default:

        break;

    }

    if ( ! result )

        ret = NULL;

    else

        ret = waitinfo.addr;

    CYG_ASSERT( (!result) || (NULL != ret), "Good result but no alloc!" );

    CYG_ASSERTCLASS( this, "Bad this pointer");

    CYG_REPORT_RETVAL( ret );

    return ret;

}

#endif

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

// get some memory, return NULL if none available

template 

inline cyg_uint8 *

Cyg_Mempolt2::try_alloc( cyg_int32 size )

{

    CYG_REPORT_FUNCTION();

    // Prevent preemption

    Cyg_Scheduler::lock();

    CYG_ASSERTCLASS( this, "Bad this pointer");

    cyg_uint8 *ret = pool.try_alloc( size );

    CYG_ASSERTCLASS( this, "Bad this pointer");

    // Unlock the scheduler and maybe switch threads

    Cyg_Scheduler::unlock();

    return ret;

}

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

// resize existing allocation, if oldsize is non-NULL, previous

// allocation size is placed into it. If previous size not available,

// it is set to 0. NB previous allocation size may have been rounded up.

// Occasionally the allocation can be adjusted *backwards* as well as,

// or instead of forwards, therefore the address of the resized

// allocation is returned, or NULL if no resizing was possible.

// Note that this differs from ::realloc() in that no attempt is

// made to call malloc() if resizing is not possible - that is left

// to higher layers. The data is copied from old to new though.

// The effects of alloc_ptr==NULL or newsize==0 are undefined

template 

cyg_uint8 *

Cyg_Mempolt2::resize_alloc( cyg_uint8 *alloc_ptr, cyg_int32 newsize,

                               cyg_int32 *oldsize )

{

    CYG_REPORT_FUNCTION();

    // Prevent preemption

    Cyg_Scheduler::lock();

    CYG_ASSERTCLASS( this, "Bad this pointer");

    cyg_uint8 *ret = pool.resize_alloc( alloc_ptr, newsize, oldsize );

    CYG_ASSERTCLASS( this, "Bad this pointer");

    // Unlock the scheduler and maybe switch threads

    Cyg_Scheduler::unlock();

    return ret;

}

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

// free the memory back to the pool

template 

cyg_bool

Cyg_Mempolt2::free( cyg_uint8 *p, cyg_int32 size )

{

    CYG_REPORT_FUNCTION();

    // Prevent preemption

    Cyg_Scheduler::lock();

    CYG_ASSERTCLASS( this, "Bad this pointer");

    cyg_int32 ret = pool.free( p, size );

    // anyone waiting?

    if ( !(queue.empty()) ) {

        Mempolt2WaitInfo *p;

        Cyg_Thread     *thread;

#ifdef CYGIMP_MEM_T_ONEFREE_TO_ONEALLOC

        thread = queue.dequeue();

        p = (Mempolt2WaitInfo *)(thread->get_wait_info());

        CYG_ASSERT( NULL == p->addr, "Thread already awoken?" );

        cyg_uint8 *mem;

        mem = pool.try_alloc( p->size );

        CYG_ASSERT( NULL != mem, "That should have succeeded" );

        thread->set_wake_reason( Cyg_Thread::DONE );

        thread->wake();

        // return the successful value to it

        p->addr = mem;

#else

        Cyg_ThreadQueue holding;

        do {

            thread = queue.dequeue();

            p = (Mempolt2WaitInfo *)(thread->get_wait_info());

            CYG_ASSERT( NULL == p->addr, "Thread already awoken?" );

            cyg_uint8 *mem;

            if ( NULL != (mem = pool.try_alloc( p->size )) ) {

                // success!  awaken the thread

                thread->set_wake_reason( Cyg_Thread::DONE );

                thread->wake();

                // return the successful value to it

                p->addr = mem;

            }

            else {

                // preserve the entry on the holding queue

                holding.enqueue( thread );

            }

        } while ( !(queue.empty()) );

        // Now re-queue the unaffected threads back into the pool queue

        // (no pun intended)

        while ( !(holding.empty()) ) {

            queue.enqueue( holding.dequeue() );

        }

#endif // CYGIMP_MEM_T_ONEFREE_TO_ONEALLOC

    }

    // Unlock the scheduler and maybe switch threads

    Cyg_Scheduler::unlock();

    CYG_REPORT_RETVAL( ret );

    return ret;

}

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

// Get memory pool status

// Needs atomicity protection (maybe)

template 

inline void

Cyg_Mempolt2::get_status( cyg_mempool_status_flag_t flags,

                             Cyg_Mempool_Status &status )

{

    // Prevent preemption

    Cyg_Scheduler::lock();

    CYG_ASSERTCLASS( this, "Bad this pointer");

    if (0 != (flags & CYG_MEMPOOL_STAT_WAITING)) {

        status.waiting = (0 == queue.empty());

    }

    pool.get_status(flags, status);

    // Unlock the scheduler and maybe switch threads

    Cyg_Scheduler::unlock();

}

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

// debugging/assert function

#ifdef CYGDBG_USE_ASSERTS

template 

inline cyg_bool

Cyg_Mempolt2::check_this(cyg_assert_class_zeal zeal) const

{

    CYG_REPORT_FUNCTION();

    if ( Cyg_Thread::DESTRUCT == Cyg_Thread::self()->get_wake_reason() )

        // then the whole thing is invalid, and we know it.

        // so return OK, since this check should NOT make an error.

        return true;

    // check that we have a non-NULL pointer first

    if( this == NULL ) return false;

    return true;

}

#endif

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

#endif // ifndef CYGONCE_MEMALLOC_MEMPOLT2_INL

// EOF mempolt2.inl