// Copyright (c) 1996-2009 Nokia Corporation and/or its subsidiary(-ies).

// All rights reserved.

// This component and the accompanying materials are made available

// under the terms of the License "Eclipse Public License v1.0"

// which accompanies this distribution, and is available

// at the URL "http://www.eclipse.org/legal/epl-v10.html".

//

// Initial Contributors:

// Nokia Corporation - initial contribution.

//

// Contributors:

//

// Description:

// Very simple test of CPU overhead

// 

//

/**

 @file bf_cpu.cpp

*/

#include <e32std.h>

#include <e32std_private.h>

#include <e32base.h>

#include <e32base_private.h>

#include <e32test.h>

#include <e32svr.h>

#include "user_config.h"

#define TEST_WRITE_OVERHEAD

#define NON_WRITING_LOOPS

const TInt KAverageOverInSeconds=10;	///< Number of seconds to run tests for

TInt64 Count;				///< Global variable used to count number of operations completed

RSemaphore CountSem;		///< control access to Count;

RTest test(_L("BF_CPU"));

TBusLocalDrive	drive;

TLocalDriveCapsV2Buf driveInfo;

LOCAL_D TBool StopTest;		///< set to ETrue to stop the test

#ifdef TEST_WRITE_OVERHEAD

LOCAL_D TBool StopZeroTest;

LOCAL_C TInt WriteZeroThread(TAny*)

	/**

	 * Performs writes of zero length continuously

	 */

	{

#if 0

	_LIT( KPanicCat, "ZERWRTH" );

#endif

	TBuf8<513> buf;

	buf.SetLength(513);

	while( !StopZeroTest )

		{

		// Return values are bogus when doing overhead testing

		drive.Write( 513, buf );

		}

	return KErrNone;

	}

#endif

LOCAL_C TInt WriteThread(TAny*)

	/**

	 * Performs writes continuously

	 */

	{

	_LIT( KPanicCat, "WRTHRD" );

	TBuf8<512> buf;

	buf.SetLength(512);

	buf.Fill(0xFF);		// all 0xFF so we can repeatedly overwrite

	while( !StopTest )

		{

		TInt r = drive.Write( 0, buf );

		if( KErrNone != r )

			{

			User::Panic( KPanicCat, r );

			}

		}

	return KErrNone;

	}

LOCAL_C TInt CpuThread(TAny*)

	/**

	 * Just increments the counter

	 */

	{

	while( !StopTest )

		{

		CountSem.Wait();

#ifdef NON_WRITING_LOOPS

		for( volatile TInt i = 5000; i > 0; i-- );

#endif

		++Count;

		CountSem.Signal();

		}

	return KErrNone;

	}

void runTest()

	{

    RThread writeThread;

	TInt r=writeThread.Create(_L("WRITER"),WriteThread,KDefaultStackSize,&User::Heap(),NULL);

	test(r==KErrNone);

	RThread cpuThread;

	r=cpuThread.Create(_L("CPU-ER"),CpuThread,KDefaultStackSize,&User::Heap(),NULL);

	test(r==KErrNone);

#ifdef TEST_WRITE_OVERHEAD

    RThread writeZeroThread;

	r=writeZeroThread.Create(_L("WRITERZERO"),WriteZeroThread,KDefaultStackSize,&User::Heap(),NULL);

	test(r==KErrNone);

#endif

	r = CountSem.CreateLocal(1);

	test(r==KErrNone);

	StopTest = EFalse;	// allow the test to run

    TRequestStatus deadStatWrite;

    TRequestStatus deadStatCpu;

	writeThread.Logon( deadStatWrite );

	cpuThread.Logon( deadStatCpu );

	// make writer thread have priority over CPU usage thread

	writeThread.SetPriority( EPriorityMore );

	// make this thread highest priority

	RThread().SetPriority( EPriorityMuchMore );

    cpuThread.Resume();

#ifdef TEST_WRITE_OVERHEAD

    TRequestStatus deadStatWriteZero;

	writeZeroThread.Logon( deadStatWriteZero );

	// make writer thread have priority over CPU usage thread

	writeZeroThread.SetPriority( EPriorityMore );

	StopZeroTest = EFalse;

	writeZeroThread.Resume();

#endif

	// wait for thread to initialise

	User::After(1000000);

	CountSem.Wait();

	Count=0;

	CountSem.Signal();

    User::After(KAverageOverInSeconds*1000000);

	CountSem.Wait();

	TInt64 noWriteCount( Count );	// number of counts when not writing

	CountSem.Signal();

#ifdef TEST_WRITE_OVERHEAD

	// kill the zero writer

	StopZeroTest = ETrue;

	User::WaitForRequest( deadStatWriteZero );

	CLOSE_AND_WAIT(writeZeroThread);

#endif

	test.Printf( _L("Loops without writing = %ld"), noWriteCount );

	// start write thread

	writeThread.Resume();

	User::After(1000000);

	CountSem.Wait();

	Count=0;

	CountSem.Signal();

    User::After(KAverageOverInSeconds*1000000);

	CountSem.Wait();

	TInt64 withWriteCount( Count );	// number of counts when writing

	CountSem.Signal();

	test.Printf( _L("Loops while writing = %ld"), withWriteCount );

	// tell test to stop and wait for thread to exit.

	cpuThread.Kill(KErrNone);

	StopTest = ETrue;

	User::WaitForRequest( deadStatWrite );

	CLOSE_AND_WAIT(writeThread);

	CLOSE_AND_WAIT(cpuThread);

	TInt64 calc( withWriteCount );

	calc = calc * 100;

	calc = calc / noWriteCount;

	test.Printf( _L("%% CPU used = %d"), 100 - I64LOW(calc) );

    }

LOCAL_C TInt EraseSegment( TInt aSegmentNumber )

	/**

	 * Erases a segment on Flash

	 *

	 * @param aSegmentNumber index of segment to erase

	 * @return KErrNone or error code

	 */

	{

	TInt offset = aSegmentNumber * driveInfo().iEraseBlockSize;

	TInt r = drive.Format( offset, driveInfo().iEraseBlockSize );

	test.Printf( _L("erase returns %d"), r );

	return  r;

	}

void Initialize()

	/**

	 * Open channel to media driver

	 */

	{

	//

	// Load the media driver

	//

#ifndef SKIP_PDD_LOAD

	test.Printf( _L("Loading %S\n"), &KLfsDriverName );

	TInt r = User::LoadPhysicalDevice( KLfsDriverName );

	test( KErrNone == r || KErrAlreadyExists == r );

#endif

#ifdef UNMOUNT_DRIVE

	RFs fs;

	test( KErrNone == fs.Connect() );

#if 0

	// XXX not EKA2

	test( KErrNone == fs.SetDefaultPath( _L("Z:\\") ) );

#endif

	TFullName name;

	fs.FileSystemName( name, KLffsLogicalDriveNumber );

	if( name.Length() > 0 )

		{

		test.Printf( _L("Unmounting drive") );

		test( KErrNone == fs.DismountFileSystem( _L("Lffs"), KLffsLogicalDriveNumber) );

		User::After( 2000000 );

		test.Printf( _L("Drive unmounted") );

		}

	fs.Close();

#endif

	//

	// Open a TBusLogicalDevice to it

	//

	test.Printf( _L("Opening media channel\n") );

	TBool changedFlag = EFalse;

	test( KErrNone == drive.Connect( KDriveNumber, changedFlag ) );

	//

	// Get size of Flash drive, block size, block count

	//

    drive.Caps(driveInfo);

	}

TInt E32Main()

    {

    test.Title();

    test.Start(_L("Testing CPU overhead"));

	Initialize();

	test.Printf( _L("Erasing first segment") );

	TInt r = EraseSegment( 0 );

	test( KErrNone == r );

	test.Printf( _L("Segment erased") );

	runTest();

	drive.Disconnect();

    test.End();

	return(KErrNone);

    }