source: src/tests/concurrent/examples/boundedBufferEXT.c @ 90cedbdd

//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// boundedBufferEXT.c --
//
// Author           : Peter A. Buhr
// Created On       : Wed Apr 18 22:52:12 2018
// Last Modified By : Peter A. Buhr
// Last Modified On : Wed May  2 16:12:58 2018
// Update Count     : 7
//

#include <stdlib>                                                                               // random
#include <fstream>
#include <kernel>
#include <thread>
#include <unistd.h>                                                                             // getpid

//Duration default_preemption() { return 0; }

enum { BufferSize = 50 };

forall( otype T ) {
        monitor Buffer {
                int front, back, count;
                T elements[BufferSize];
        }; // Buffer

        void ?{}( Buffer(T) & buffer ) with( buffer ) { [front, back, count] = 0; }

        int query( Buffer(T) & buffer ) { return buffer.count; } // read-only, no mutual exclusion

        T remove( Buffer(T) & mutex buffer );                           // forward

        void insert( Buffer(T) & mutex buffer, T elem ) with( buffer ) {
                if ( count == BufferSize ) waitfor( remove, buffer );
                elements[back] = elem;
                back = ( back + 1 ) % BufferSize;
                count += 1;
        } // insert

        T remove( Buffer(T) & mutex buffer ) with( buffer ) {
                if ( count == 0 ) waitfor( insert, buffer );
                T elem = elements[front];
                front = ( front + 1 ) % BufferSize;
                count -= 1;
                return elem;
        } // remove
}

const int Sentinel = -1;

thread Producer {
        Buffer(int) & buffer;
        unsigned int N;
};
void main( Producer & prod ) with( prod ) {
        for ( int i = 1; i <= N; i += 1 ) {
                yield( random( 5 ) );
                insert( buffer, 1 );
        } // for
}
void ?{}( Producer & prod, Buffer(int) * buffer, int N ) {
        &prod.buffer = buffer;
        prod.N = N;
}

thread Consumer {
        Buffer(int) & buffer;
        int & sum;                                                                                      // summation of producer values
};
void main( Consumer & cons ) with( cons ) {
        sum = 0;
        for ( ;; ) {
                yield( random( 5 ) );
                int item = remove( buffer );
          if ( item == Sentinel ) break;                                        // sentinel ?
                sum += item;
        } // for
}
void ?{}( Consumer & cons, Buffer(int) * buffer, int & sum ) {
        &cons.buffer = buffer;
        &cons.sum = &sum;
}

int main() {
        Buffer(int) buffer;
        enum { Prods = 4, Cons = 5 };
        Producer * prods[Prods];
        Consumer * cons[Cons];
        int sums[Cons];
        int i;
        processor p;

        //srandom( getpid() );
        srandom( 1003 );

        for ( i = 0; i < Cons; i += 1 ) {                                       // create consumers
                cons[i] = new( &buffer, sums[i] );
        } // for
        for ( i = 0; i < Prods; i += 1 ) {                                      // create producers
                prods[i] = new( &buffer, 100000 );
        } // for

        for ( i = 0; i < Prods; i += 1 ) {                                      // wait for producers to finish
                delete( prods[i] );
        } // for
        for ( i = 0; i < Cons; i += 1 ) {                                       // generate sentinal values to stop consumers
                insert( buffer, Sentinel );
        } // for
        int sum = 0;
        for ( i = 0; i < Cons; i += 1 ) {                                       // wait for consumers to finish
                delete( cons[i] );
                sum += sums[i];
        } // for
        sout | "total:" | sum | endl;
}

// Local Variables: //
// tab-width: 4 //
// compile-command: "cfa boundedBufferEXT.c" //
// End: //