int main(int argc, char **argv) {
int recv_x = 1, size, rank;
MPI_Status status;
MPI_Init(&argc, &argv);
MPI_Comm_size(MPI_COMM_WORLD, &size); /* Get nr of tasks */
MPI_Comm_rank(MPI_COMM_WORLD, &rank); /* Get id of this process */
MC_ignore(&(status.count), sizeof(status.count));
if(rank==0){
while (recv_x>=0) {
MPI_Recv(&recv_x, 1, MPI_INT, MPI_ANY_SOURCE, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
}
}else{
while (x >= 0) {
if (MC_random(0,1) == 0) {
x -= 1;
} else {
x += 1;
}
printf("x=%d\n", x);
MPI_Send(&x, 1, MPI_INT, 0, 42, MPI_COMM_WORLD);
}
}
MPI_Finalize();
return 0;
}
int main(int argc, char **argv){
int size;
int rank;
int recv_buff;
MPI_Status status;
xbt_dynar_t requests = xbt_dynar_new(sizeof(int), NULL);
/* Initialize MPI */
int err = MPI_Init(&argc, &argv);
if(err != MPI_SUCCESS){
printf("MPI initialization failed !\n");
exit(1);
}
MC_automaton_new_propositional_symbol_pointer("r", &r);
MC_automaton_new_propositional_symbol_pointer("cs", &cs);
MC_ignore(&(status.count), sizeof(status.count));
/* Get number of processes */
MPI_Comm_size(MPI_COMM_WORLD, &size);
/* Get id of this process */
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
if(rank == 0){ /* Coordinator */
int CS_used = 0;
while(1){
MPI_Recv(&recv_buff, 1, MPI_INT, MPI_ANY_SOURCE, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
if(status.MPI_TAG == REQUEST_TAG){
if(CS_used){
printf("CS already used.\n");
xbt_dynar_push(requests, &recv_buff);
}else{
if(recv_buff != size - 1){
printf("CS idle. Grant immediatly.\n");
MPI_Send(&rank, 1, MPI_INT, recv_buff, GRANT_TAG, MPI_COMM_WORLD);
CS_used = 1;
}
}
}else{
if(!xbt_dynar_is_empty(requests)){
printf("CS release. Grant to queued requests (queue size: %lu)", xbt_dynar_length(requests));
xbt_dynar_shift(requests, &recv_buff);
if(recv_buff != size - 1){
MPI_Send(&rank, 1, MPI_INT, recv_buff, GRANT_TAG, MPI_COMM_WORLD);
CS_used = 1;
}else{
xbt_dynar_push(requests, &recv_buff);
CS_used = 0;
}
}else{
printf("CS release. Resource now idle.\n");
CS_used = 0;
}
}
}
}else{ /* Client */
while(1){
printf("%d asks the request.\n", rank);
MPI_Send(&rank, 1, MPI_INT, 0, REQUEST_TAG, MPI_COMM_WORLD);
if(rank == size - 1){
r = 1;
cs = 0;
}
MPI_Recv(&recv_buff, 1, MPI_INT, 0, MPI_ANY_TAG, MPI_COMM_WORLD, &status);
if(status.MPI_TAG == GRANT_TAG && rank == size - 1){
cs = 1;
r = 0;
}
printf("%d got the answer. Release it.\n", rank);
MPI_Send(&rank, 1, MPI_INT, 0, RELEASE_TAG, MPI_COMM_WORLD);
if(rank == size - 1){
r = 0;
cs = 0;
}
}
}
MPI_Finalize();
return 0;
}
