i have this thingy here :

function numOfPackets(bufferSize, packetSize) {
    if (bufferSize <= 0 || packetSize > bufferSize) return 0;
    if (packetSize < 0) throw Error();
    var out = 0;


    for(;;){
     out++; 
     bufferSize = bufferSize - packetSize;
     if( packetSize > bufferSize ) break;
    }

    return out;
}

which i run at often , can u give me more efficent variant of it?