Java-oshmem: some examples

This commit was SVN r31844.

examples/Hello_oshmem.java

@@ -0,0 +1,12 @@
+import shmem.*;
+
+public class Hello_oshmem
+{
+    public static void main(String[] args)
+    {
+        ShMem.startPEs(0);
+        int nproc = ShMem.getNumPEs();
+        int proc  = ShMem.getMyPE();
+        System.out.println("Hello, world, I am "+ proc +" of "+ nproc);
+    }
+}

examples/Ring_oshmem.java

@@ -0,0 +1,54 @@
+import shmem.*;
+
+public class Ring_oshmem
+{
+    public static void main(String[] args) throws ShMemException
+    {
+        ShMem.startPEs(0);
+        int nproc = ShMem.getNumPEs();
+        int proc  = ShMem.getMyPE();
+        Addr rbuf = new Addr(4); // One integer value.
+        rbuf.putInt(-1);
+        int message = 10;
+
+        // Calculate the PE number of the next process in the ring. Use the
+        // modulus operator so that the last process "wraps around" to PE 0.
+        int next = (proc + 1) % nproc;
+
+        if(proc == 0)
+        {
+            System.out.println("Process 0 puts message "+ message +" to "+
+                               next +" ("+ nproc +" processes in ring)");
+
+            rbuf.putInt(message, next);
+        }
+
+        // Pass the message around the ring. The exit mechanism works as
+        // follows: the message (a positive integer) is passed around the
+        // ring. Each time it passes PE 0, it is decremented. When each
+        // processes receives a message containing a 0 value, it passes the
+        // message on to the next process and then quits. By passing the 0
+        // message first, every process gets the 0 message and can quit
+        // normally.
+
+        while(message > 0)
+        {
+            rbuf.waitUntilInt(ShMem.CMP_EQ, message);
+
+            if(proc == 0)
+            {
+                message--;
+                System.out.println("Process 0 decremented value: "+ message);
+            }
+
+            rbuf.putInt(message, next);
+
+            if(proc != 0)
+                message--;
+        }
+
+        // All done
+        rbuf.free();
+        System.out.println("Process "+ proc +" exiting");
+    }
+}

examples/oshmem_circular_shift.java

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+import shmem.*;
+
+public class oshmem_circular_shift
+{
+    public static void main(String[] args) throws ShMemException
+    {
+        ShMem.startPEs(0);
+
+        int numPEs = ShMem.getNumPEs(),
+            myPE   = ShMem.getMyPE(),
+            peer   = (myPE + 1) % numPEs;
+
+        int[] aaa = new int[1];
+        Addr  bbb = new Addr(4);
+
+        System.out.println("Process "+ myPE +" gets message from "+
+                           peer +" ("+ numPEs +" processes in ring)");
+
+        bbb.getInt(aaa, 1, peer);
+        ShMem.barrierAll();
+        bbb.free();
+        System.out.println("Process "+ myPE +" exiting");
+    }
+}

examples/oshmem_max_reduction.java

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+import shmem.*;
+import java.nio.*;
+
+public class oshmem_max_reduction
+{
+    private static final int N = 3;
+
+    public static void main(String[] args) throws ShMemException
+    {
+        ShMem.startPEs(0);
+
+        int numPEs = ShMem.getNumPEs(),
+            myPE   = ShMem.getMyPE();
+
+        Addr src   = new Addr(8 * N), // long is 8 bytes.
+             dst   = new Addr(8 * N),
+             pWrk  = new Addr(8 * ShMem.REDUCE_SYNC_SIZE),
+             pSync = new Addr(8 * ShMem.BCAST_SYNC_SIZE);
+
+        LongBuffer srcBuf   = src.asLongBuffer(),
+                   dstBuf   = dst.asLongBuffer(),
+                   pSyncBuf = pSync.asLongBuffer();
+
+        for(int i = 0; i < ShMem.BCAST_SYNC_SIZE; i++)
+            pSyncBuf.put(i, ShMem.SYNC_VALUE);
+
+        for(int i = 0; i < N; i++)
+            srcBuf.put(i, myPE + i);
+
+        ShMem.barrierAll();
+        dst.maxToAllLong(src, N, 0, 0, numPEs, pWrk, pSync);
+
+        StringBuilder sb = new StringBuilder();
+        sb.append(myPE +"/"+ numPEs +" dst =");
+
+        for(int i = 0; i < N; i++)
+            sb.append(" "+ dstBuf.get(i));
+
+        sb.append("\n");
+        System.out.print(sb);
+
+        src.free();
+        dst.free();
+        pWrk.free();
+        pSync.free();
+    }
+}

examples/oshmem_strided_puts.java

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+import shmem.*;
+import java.nio.*;
+
+public class oshmem_strided_puts
+{
+    public static void main(String[] args) throws ShMemException
+    {
+        ShMem.startPEs(0);
+        int me = ShMem.getMyPE();
+
+        short[] source = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
+        Addr    target = new Addr(2 * 10); // short is 2 bytes.
+
+        if(me == 0)
+        {
+            /* put 10 words into target on PE 1 */
+            target.iPutShort(source, 1, 2, 5, 1);
+        }
+
+        ShMem.barrierAll(); // sync sender and receiver
+
+        if(me == 1)
+        {
+            ShortBuffer buf = target.asShortBuffer();
+            System.out.printf("target on PE %d is %d %d %d %d %d\n", me,
+                              buf.get(0), buf.get(1), buf.get(2),
+                              buf.get(3), buf.get(4));
+        }
+
+        ShMem.barrierAll(); // sync before exiting
+        target.free();
+    }
+}

examples/oshmem_symmetric_data.java

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+import shmem.*;
+import java.nio.*;
+
+public class oshmem_symmetric_data
+{
+    private static final int SIZE = 16;
+
+    public static void main(String[] args) throws ShMemException
+    {
+        ShMem.startPEs(0);
+
+        int numPE = ShMem.getNumPEs(),
+            myPE  = ShMem.getMyPE();
+
+        int[] source = new int[SIZE];
+        Addr  target = new Addr(4 * SIZE); // int is 4 bytes
+
+        if(myPE == 0)
+        {
+            // initialize array
+            for(int i = 0; i < SIZE; i++)
+                source[i] = i;
+
+            // local, not symmetric
+            // static makes it symmetric
+            // put "size" words into target on each PE
+            for(int i = 1; i < numPE; i++)
+                target.putInt(source, SIZE, i);
+        }
+
+        ShMem.barrierAll(); // sync sender and receiver
+
+        if(myPE != 0)
+        {
+            StringBuilder sb = new StringBuilder();
+            sb.append("Target on PE "+ myPE +" is \t");
+            IntBuffer buf = target.asIntBuffer();
+
+            for(int i = 0; i < SIZE; i++)
+                sb.append(buf.get(i) +" \t");
+
+            sb.append('\n');
+            System.out.print(sb);
+        }
+
+        ShMem.barrierAll(); // sync before exiting
+        target.free();
+    }
+}