/* Destroy the threadpool */
void thpool_destroy(thpool_* thpool_p){
volatile int threads_total = thpool_p->num_threads_alive;
/* End each thread 's infinite loop */
threads_keepalive = 0;
/* Give one second to kill idle threads */
double TIMEOUT = 1.0;
time_t start, end;
double tpassed = 0.0;
time (&start);
while (tpassed < TIMEOUT && thpool_p->num_threads_alive){
bsem_post_all(thpool_p->jobqueue_p->has_jobs);
time (&end);
tpassed = difftime(end,start);
}
/* Poll remaining threads */
while (thpool_p->num_threads_alive){
bsem_post_all(thpool_p->jobqueue_p->has_jobs);
sleep(1);
}
/* Job queue cleanup */
jobqueue_destroy(thpool_p);
free(thpool_p->jobqueue_p);
/* Deallocs */
int n;
for (n=0; n < threads_total; n++){
thread_destroy(thpool_p->threads[n]);
}
free(thpool_p->threads);
free(thpool_p);
}
/* Initialise thread pool */
struct thpool_*
thpool_init(int num_threads)
{
threads_on_hold = 0;
threads_keepalive = 1;
if (num_threads < 0){
num_threads = 0;
}
/* Make new thread pool */
thpool_* thpool_p;
thpool_p = (struct thpool_*)malloc(sizeof(struct thpool_));
if (thpool_p == NULL) {
fprintf(stderr, "thpool_init(): Could not allocate memory for thread pool\n");
return NULL;
}
thpool_p->num_threads_alive = 0;
thpool_p->num_threads_working = 0;
/* Initialise the job queue */
if (jobqueue_init(thpool_p) == -1) {
fprintf(stderr, "thpool_init(): Could not allocate memory for job queue\n");
free(thpool_p);
return NULL;
}
/* Make threads in pool */
thpool_p->threads = (struct thread**)malloc(num_threads * sizeof(struct thread *));
if (thpool_p->threads == NULL){
fprintf(stderr, "thpool_init(): Could not allocate memory for threads\n");
jobqueue_destroy(thpool_p);
free(thpool_p->jobqueue_p);
free(thpool_p);
return NULL;
}
/* Make tag list */
taglist *tlist;
tlist = (taglist *) malloc(sizeof(taglist));
if (tlist == NULL) {
fprintf(stderr, "thpool_init(): Could not allocate memory for job queue\n");
jobqueue_destroy(thpool_p);
free(thpool_p->jobqueue_p);
free(thpool_p->threads);
free(thpool_p);
return NULL;
}
tlist->num = TAGLIST_SIZE;
tlist->tags = (tag *) calloc(tlist->num, sizeof(tag));
if (tlist->tags == NULL) {
fprintf(stderr, "thpool_init(): Could not allocate memory for tag list\n");
jobqueue_destroy(thpool_p);
free(thpool_p->jobqueue_p);
free(thpool_p->threads);
free(thpool_p);
free(tlist);
return NULL;
}
pthread_mutex_init(&tlist->lock, NULL);
thpool_p->tlist = tlist;
pthread_mutex_init(&(thpool_p->thcount_lock), NULL);
pthread_cond_init(&thpool_p->threads_all_idle, NULL);
/* Thread init */
for (int n = 0; n < num_threads; n++) {
thread_init(thpool_p, &thpool_p->threads[n], n);
if (THPOOL_DEBUG)
printf("THPOOL_DEBUG: Created thread %d in pool \n", n);
}
/* Wait for threads to initialize */
while (thpool_p->num_threads_alive != num_threads) {}
return thpool_p;
}
