C++ API Reference
threadingLockTests/threadingLockTests.cpp
//-
// ==========================================================================
// Copyright 1995,2006,2008 Autodesk, Inc. All rights reserved.
//
// Use of this software is subject to the terms of the Autodesk
// license agreement provided at the time of installation or download,
// or which otherwise accompanies this software in either electronic
// or hard copy form.
// ==========================================================================
//+
#include <maya/MSimple.h>
#include <maya/MGlobal.h>
#include <maya/MIOStream.h>
#include <maya/MTimer.h>
#include <maya/MMutexLock.h>
#include <maya/MSpinLock.h>
#include <maya/MAtomic.h>
#include <maya/MThreadUtils.h>
#include <tbb/blocked_range.h>
#include <tbb/parallel_for.h>
DeclareSimpleCommand( threadingLockTests, PLUGIN_COMPANY, "3.0");
int doMutexCalc(int iterations, int val)
{
int sum = 0;
MMutexLock mutex;
tbb::parallel_for(tbb::blocked_range<int>(0, iterations),
[&](const tbb::blocked_range<int> &br) {
for (int i = br.begin(); i < br.end(); i++) {
mutex.lock();
sum += val;
mutex.unlock();
}
});
return sum;
}
int doSpinCalc(int iterations, int val)
{
int sum = 0;
MSpinLock mutex;
tbb::parallel_for(tbb::blocked_range<int>(0, iterations),
[&](const tbb::blocked_range<int> &br) {
for (int i = br.begin(); i < br.end(); i++) {
mutex.lock();
sum += val;
mutex.unlock();
}
});
return sum;
}
int doAtomicCalc(int iterations, int val)
{
int sum = 0;
tbb::parallel_for(tbb::blocked_range<int>(0, iterations),
[&](const tbb::blocked_range<int> &br) {
for (int i = br.begin(); i < br.end(); i++) {
MAtomic::increment(&sum, val);
}
});
return sum;
}
int doReductionCalc(int iterations, int val)
{
int sum = 0;
tbb::parallel_for(tbb::blocked_range<int>(0, iterations),
[&](const tbb::blocked_range<int> &br) {
for (int i = br.begin(); i < br.end(); i++) {
sum += val;
}
});
return sum;
}
int doUnsafeCalc(int iterations, int val)
{
int sum = 0;
tbb::parallel_for(tbb::blocked_range<int>(0, iterations),
[&](const tbb::blocked_range<int> &br) {
for (int i = br.begin(); i < br.end(); i++) {
sum += val;
}
});
return sum;
}
int doSerialCalc(int iterations, int val)
{
int sum = 0;
for(int i=0; i<iterations; i++) {
sum += val;
}
return sum;
}
MStatus threadingLockTests::doIt( const MArgList& args )
{
MStatus stat;
if ( MS::kSuccess != stat )
cout<<"Error creating curve."<<endl;
if(args.length() != 1) {
MString str = MString("Invalid number of arguments, usage: threadingLockTests 1000000");
}
// do this if we are using an OpenMP implementation that is not the same as Maya's.
// Even if it is the same, it does no harm to make this call.
printf("In threadedLockTests, numthreads %d\n", MThreadUtils::getNumThreads());
int iterations = args.asInt( 0, &stat );
int increment = 2;
int sum = 0;
int repeat = 1;
MTimer timer;
MString out;
// Mutex lock calculation
timer.beginTimer();
for(int i=0; i<repeat; i++) {
sum = doMutexCalc(iterations, increment);
if(sum != iterations*increment) {
printf("doMutexCalc failed, sum %d\n", sum);
break;
}
}
timer.endTimer();
out = MString("Runtime doMutexCalc ") + timer.elapsedTime();
// Spin mutex lock calculation
timer.beginTimer();
for(int i=0; i<repeat; i++) {
sum = doSpinCalc(iterations, increment);
if(sum != iterations*increment) {
printf("doSpinCalc failed, sum %d\n", sum);
break;
}
}
timer.endTimer();
out = MString("Runtime doSpinCalc ") + timer.elapsedTime();
// Atomic calculation
timer.beginTimer();
for(int i=0; i<repeat; i++) {
sum = doAtomicCalc(iterations, increment);
if(sum != iterations*increment) {
printf("doAtomicCalc failed, sum %d\n", sum);
break;
}
}
timer.endTimer();
out = MString("Runtime doAtomicCalc ") + timer.elapsedTime();
// Reduction calculation
timer.beginTimer();
for(int i=0; i<repeat; i++) {
sum = doReductionCalc(iterations, increment);
if(sum != iterations*increment) {
printf("doReductionCalc failed, sum %d\n", sum);
break;
}
}
timer.endTimer();
out = MString("Runtime doReductionCalc ") + timer.elapsedTime();
// Unsafe calculation (race condition)
timer.beginTimer();
for(int i=0; i<repeat; i++) {
sum = doUnsafeCalc(iterations, increment);
if(sum != iterations*increment) {
printf("doUnsafeCalc failed, sum %d\n", sum);
break;
}
}
timer.endTimer();
out = MString("Runtime doUnsafeCalc ") + timer.elapsedTime();
// Unthreaded calculation
timer.beginTimer();
for(int i=0; i<repeat; i++) {
sum = doSerialCalc(iterations, increment);
if(sum != iterations*increment) {
printf("doUnthreadedCalc failed, sum %d\n", sum);
break;
}
}
timer.endTimer();
out = MString("Runtime doUnthreadedCalc ") + timer.elapsedTime();
return stat;
}