Cudakernel.java

package Jcuda;
/*
 * JCuda Model Example - Java bindings/wrappers for NVIDIA CUDA driver and runtime API
 */
import static jcuda.driver.JCudaDriver.*;
import java.io.*;
import jcuda.*;
import jcuda.driver.*;
import Jcuda.MathFunc;


/**
 * This is class demonstrates how to use the JCuda driver
 * bindings to load and execute a ModelSim kernel.
 * The sample reads a CUDA file, compiles it to a PTX file
 * using NVCC, loads the PTX file as a module and executes
 * the kernel function. <br />
 */
public class Cudakernel
{
    /**
     * Entry point of this sample
     *
     * @param args Not used
     * @throws IOException If an IO error occurs
     */
    public static void main(String args[]) throws IOException
    {
    	
    	long t0=System.currentTimeMillis();   
    	
        // Enable exceptions and omit all subsequent error checks
        JCudaDriver.setExceptionsEnabled(true);

        // Create the PTX file by calling the NVCC
        String ptxFileName = preparePtxFile("ModelKernel.cu");
        
        
        // Initialize the driver and create a context for the first device.
        cuInit(0);
        CUdevice device = new CUdevice();
        cuDeviceGet(device, 0);
        CUcontext context = new CUcontext();
        cuCtxCreate(context, 0, device);

        int sims = 216;
        for (int k = 0; k < sims; k++)
        {
        	
        // Load the ptx file.
        CUmodule module = new CUmodule();
        cuModuleLoad(module, ptxFileName);

        
        	
        // Obtain a function pointer to the "position profit-and-loss simulation" function.
        CUfunction function = new CUfunction();
        cuModuleGetFunction(function, module, "kernelSim");

        int prices[] = MathFunc.getPrices("data17.dat");
        int numElements = prices.length;  //num of elements

        // Allocate and fill the host input data  
        float hostInputA[] = MathFunc.getZscore(numElements);
        float hostInputB[] = MathFunc.getRet(numElements);
        
    

        // Allocate the device input data, and copy the host input data to the device
        CUdeviceptr deviceInputA = new CUdeviceptr();
        cuMemAlloc(deviceInputA, numElements * Sizeof.FLOAT);
        cuMemcpyHtoD(deviceInputA, Pointer.to(hostInputA),
            numElements * Sizeof.FLOAT);
        CUdeviceptr deviceInputB = new CUdeviceptr();
        cuMemAlloc(deviceInputB, numElements * Sizeof.FLOAT);
        cuMemcpyHtoD(deviceInputB, Pointer.to(hostInputB),
            numElements * Sizeof.FLOAT);


        // Allocate device output memory
        CUdeviceptr deviceOutput = new CUdeviceptr();
        cuMemAlloc(deviceOutput, numElements * Sizeof.FLOAT);
        CUdeviceptr deviceOutput2 = new CUdeviceptr();
        cuMemAlloc(deviceOutput2, numElements * Sizeof.FLOAT);

        // Set up the kernel parameters: A pointer to an array of pointers which point to the actual values.
        Pointer kernelParameters = Pointer.to(
            Pointer.to(new int[]{numElements}),
            Pointer.to(deviceInputA),
            Pointer.to(deviceInputB),
            Pointer.to(deviceOutput),
            Pointer.to(deviceOutput2)
        );

        // Call the kernel function.
        int blockSizeX = 512;
        int gridSizeX = (int)Math.ceil((double)numElements / blockSizeX);
        cuLaunchKernel(function,
            gridSizeX,  1, 1,      // Grid dimension
            blockSizeX, 1, 1,      // Block dimension
            0, null,               // Shared memory size and stream
            kernelParameters, null // Kernel- and extra parameters
        );
        
        cuCtxSynchronize();  //sync threads

        // Allocate host output memory and copy the device output
        // to the host.
        float hostOutput[] = new float[numElements];
        cuMemcpyDtoH(Pointer.to(hostOutput), deviceOutput,
            numElements * Sizeof.FLOAT);
        float hostOutput2[] = new float[numElements];
        cuMemcpyDtoH(Pointer.to(hostOutput2), deviceOutput2,
            numElements * Sizeof.FLOAT);

        // Verify the results
        boolean passed = true;
        for(int i = 0; i < numElements; i++)
        {
            float expected = 0;
            if (Math.abs(hostOutput[i] - expected) < 0.0)
            {
                System.out.println(
                    "At index "+i+ " found "+hostOutput[i]+
                    " but expected "+expected);
                passed = false;
                break;
            }
        }
        System.out.println("Test "+(passed?"PASSED":"FAILED"));
        
        //print output
        System.out.println("Output1");
        for (float item : hostOutput) {
            System.out.println(item);
        }
        System.out.println("Output2");
        for (float item : hostOutput2) {
            System.out.println(item);
        }

        // Clean up memory
        cuMemFree(deviceInputA);
        cuMemFree(deviceInputB);      
        cuMemFree(deviceOutput);
        cuMemFree(deviceOutput2);
        }            
        
        long t2=System.currentTimeMillis();  
        System.out.println("\nAll Operations time in ms = " + (t2-t0)*1);   
        
    }
    
    
   

    /**
     * The extension of the given file name is replaced with "ptx".
     * If the file with the resulting name does not exist, it is
     * compiled from the given file using NVCC. The name of the
     * PTX file is returned.
     *
     * @param cuFileName The name of the .CU file
     * @return The name of the PTX file
     * @throws IOException If an I/O error occurs
     */
    private static String preparePtxFile(String cuFileName) throws IOException
    {
        int endIndex = cuFileName.lastIndexOf('.');
        if (endIndex == -1)
        {
            endIndex = cuFileName.length()-1;
        }
        String ptxFileName = cuFileName.substring(0, endIndex+1)+"ptx";
        File ptxFile = new File(ptxFileName);
        if (ptxFile.exists())
        {
            return ptxFileName;
        }

        File cuFile = new File(cuFileName);
        if (!cuFile.exists())
        {
            throw new IOException("Input file not found: "+cuFileName);
        }
        String modelString = "-m"+System.getProperty("sun.arch.data.model");
        String command =
            "nvcc " + modelString + " -ptx "+
            cuFile.getPath()+" -o "+ptxFileName;

        System.out.println("Executing\n"+command);
        Process process = Runtime.getRuntime().exec(command);

        String errorMessage =
            new String(toByteArray(process.getErrorStream()));
        String outputMessage =
            new String(toByteArray(process.getInputStream()));
        int exitValue = 0;
        try
        {
            exitValue = process.waitFor();
        }
        catch (InterruptedException e)
        {
            Thread.currentThread().interrupt();
            throw new IOException(
                "Interrupted while waiting for nvcc output", e);
        }

        if (exitValue != 0)
        {
            System.out.println("nvcc process exitValue "+exitValue);
            System.out.println("errorMessage:\n"+errorMessage);
            System.out.println("outputMessage:\n"+outputMessage);
            throw new IOException(
                "Could not create .ptx file: "+errorMessage);
        }

        System.out.println("Finished creating PTX file");
        return ptxFileName;
    }

    /**
     * Fully reads the given InputStream and returns it as a byte array
     *
     * @param inputStream The input stream to read
     * @return The byte array containing the data from the input stream
     * @throws IOException If an I/O error occurs
     */
    private static byte[] toByteArray(InputStream inputStream)
        throws IOException
    {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte buffer[] = new byte[8192];
        while (true)
        {
            int read = inputStream.read(buffer);
            if (read == -1)
            {
                break;
            }
            baos.write(buffer, 0, read);
        }
        return baos.toByteArray();
    }


}