/**
* Plain barrier. This will block until all participating processes reach
* this point. Note that the participating processes must take care to have
* their sync_*() calls in the same order to avoid likely deadlock.
* @return 0 (always)
*/
int blts_sync_anon()
{
if(!init_done)
return 0;
sync_mutex_lock();
barrier_sync(0);
sync_mutex_unlock();
return 0;
}
void * jacobi(void *args){
ARGS_FOR_THREAD *args_for_me = (ARGS_FOR_THREAD *)args;
//Reset global variables after red-black
done = 0;
diff = 0;
num_iter = 0;
float local_diff = 0;
/* While not converged */
while(done != 1){
local_diff = 0;
if(num_iter % 2 == 0){ /* Every even iteration move from my_grid to temp grid */
for(int i = args_for_me->thread_id + 1; i < args_for_me->my_grid->dimension-1; i+=NUM_THREADS){ /* Row */
for(int j = 1; j < args_for_me->my_grid->dimension-1; j++){ /* Col */
int pos = i * args_for_me->my_grid->dimension + j;
args_for_me->temp->element[pos] = \
0.20*(args_for_me->my_grid->element[pos] + \
args_for_me->my_grid->element[(i - 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[(i + 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j + 1)] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j - 1)]);
local_diff += fabs(args_for_me->my_grid->element[pos] - args_for_me->temp->element[pos]);
/* Store difference in local variable */
}
}
}
else{ /* Move from temp to my_grid */
for(int i = args_for_me->thread_id + 1; i < args_for_me->my_grid->dimension-1; i+=NUM_THREADS){
for(int j = 1; j < args_for_me->my_grid->dimension-1; j++){
int pos = i * args_for_me->my_grid->dimension + j;
args_for_me->my_grid->element[pos] = \
0.20*(args_for_me->temp->element[pos] + \
args_for_me->temp->element[(i - 1) * args_for_me->temp->dimension + j] +\
args_for_me->temp->element[(i + 1) * args_for_me->temp->dimension + j] +\
args_for_me->temp->element[i * args_for_me->temp->dimension + (j + 1)] +\
args_for_me->temp->element[i * args_for_me->temp->dimension + (j - 1)]);
local_diff += fabs(args_for_me->my_grid->element[pos] - args_for_me->temp->element[pos]);
}
}
}
/* Lock to write to shared difference */
pthread_mutex_lock(&mutex);
diff += local_diff;
pthread_mutex_unlock(&mutex);
if((float)diff/((float)(args_for_me->my_grid->dimension*args_for_me->my_grid->dimension)) < (float)TOLERANCE)
done = 1;
/* Barrier sync and reset difference */
barrier_sync(&barrier);
}
}
/* 各スレッドのナップザック処理 */
void t_knapsack(int num_thread,int tid,int *P,int *W,int N,int C){
int i,j,prg;
--W;--P;
for(i=1;i<=N;i++){
/* 列をスレッドで分ける */
int t = C / num_thread + 1;
for(j=t*tid+1; j<=min(C,t*(tid+1)) ;j++){
int v = (j-W[i]>=0) ? P[i] + R[i-1][j-W[i]] : 0;
R[i][j] = max(R[i-1][j],v);
}
/* 全てのスレッドが処理を完了するまで待機 */
barrier_sync(num_thread,tid);
}
}
/* The function executed by the threads. */
void *
my_thread(void *args)
{
int thread_number = (int)args;
int num_iterations;
for(num_iterations = 0; num_iterations < NUM_ITERATIONS; num_iterations++){
printf("Thread number %d is processing for iteration %d. \n", thread_number, num_iterations);
sleep(ceil((float)rand()/(float)RAND_MAX * 10)); /* simulate some processing. */
printf("Thread %d is at the barrier. \n", thread_number);
barrier_sync(&barrier, thread_number); /* Wait here for all threads to catch up before starting the next iteration. */
}
pthread_exit(NULL);
}
/**
* Block process until each registered user reaches named barrier. Note that
* the participating processes must take care to have their sync_*() calls
* in the same order to avoid likely deadlock.
* @param tag Name of barrier, registered earlier with blts_sync_add_tag()
* @return 0 on success
*/
int blts_sync_tagged(char *tag)
{
int i, ret = 0;
if(!init_done)
return 0;
sync_mutex_lock();
i = find_tagged_barrier(tag);
if(i < 0) {
BLTS_ERROR("Sync: Named barrier '%s' not available\n", tag);
ret = -EINVAL;
} else {
BLTS_TRACE("Sync: Arriving at named barrier '%s'\n", tag);
barrier_sync(i);
}
sync_mutex_unlock();
return ret;
}
void * red_black(void *args){
ARGS_FOR_THREAD *args_for_me = (ARGS_FOR_THREAD *)args;
diff = 0;
num_iter = 0;
float local_diff;
float temp;
while(done != 1){
local_diff = 0;
for(int i = args_for_me->thread_id + 1; i < args_for_me->my_grid->dimension-1; i+=NUM_THREADS){
if(is_red == 0){ /* Operate on only red points */
if(args_for_me->thread_id % 2 == 0){ /* Alternates positions starting with Red or Black */
for(int j = 1; j < args_for_me->my_grid->dimension-1; j+=2){
/* Advance by 2 points to jump over the black point */
int pos = i * args_for_me->my_grid->dimension + j;
temp = args_for_me->my_grid->element[pos];
args_for_me->my_grid->element[pos] = \
0.20*(args_for_me->my_grid->element[pos] + \
args_for_me->my_grid->element[(i - 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[(i + 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j + 1)] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j - 1)]);
local_diff += fabs(args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + j] - temp);
}
}
else{ /* Starts one position in to start on Red */
for(int j = 2; j < args_for_me->my_grid->dimension-1; j+=2){
int pos = i * args_for_me->my_grid->dimension + j;
temp = args_for_me->my_grid->element[pos];
args_for_me->my_grid->element[pos] = \
0.20*(args_for_me->my_grid->element[pos] + \
args_for_me->my_grid->element[(i - 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[(i + 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j + 1)] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j - 1)]);
local_diff += fabs(args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + j] - temp);
}
}
}
else{ /* Operate on only black points */
if(args_for_me->thread_id % 2 == 0){ /* Starts one position in to start on black point */
for(int j = 2; j < args_for_me->my_grid->dimension-1; j+=2){
int pos = i * args_for_me->my_grid->dimension + j;
temp = args_for_me->my_grid->element[pos];
args_for_me->my_grid->element[pos] = \
0.20*(args_for_me->my_grid->element[pos] + \
args_for_me->my_grid->element[(i - 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[(i + 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j + 1)] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j - 1)]);
local_diff += fabs(args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + j] - temp);
}
}
else{
for(int j = 1; j < args_for_me->my_grid->dimension; j+=2){
int pos = i * args_for_me->my_grid->dimension + j;
temp = args_for_me->my_grid->element[pos];
args_for_me->my_grid->element[pos] = \
0.20*(args_for_me->my_grid->element[pos] + \
args_for_me->my_grid->element[(i - 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[(i + 1) * args_for_me->my_grid->dimension + j] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j + 1)] +\
args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + (j - 1)]);
local_diff += fabs(args_for_me->my_grid->element[i * args_for_me->my_grid->dimension + j] - temp);
}
}
}
}
/* Lock and store shared difference */
pthread_mutex_lock(&mutex);
diff += local_diff;
pthread_mutex_unlock(&mutex);
if((float)diff/((float)(args_for_me->my_grid->dimension*args_for_me->my_grid->dimension)) < (float)TOLERANCE)
done = 1;
/* Barrier sync, reset difference and alternate red/black */
barrier_sync(&barrier);
}
}
