-#include "main.h"
+#include <threads.h>
+
+#include "my_queue.h"
-extern unsigned int iterations;
extern private_t private;
-extern shared_mem_t *smp;
void init_private(int pid)
{
private.node = 2 + pid;
- private.value = 1 + (pid * iterations);
-
-}
-
-void init_memory()
-{
}
static unsigned int new_node()
private.node = node;
}
-void init_queue()
+void init_queue(queue_t *q)
{
unsigned int i;
pointer head;
tail = MAKE_POINTER(1, 0);
next = MAKE_POINTER(0, 0); // (NULL, 0)
- atomic_init(&smp->nodes[0].next, 0); // assumed inititalized in original example
+ atomic_init(&q->nodes[0].next, 0); // assumed inititalized in original example
- atomic_store(&smp->head, head);
- atomic_store(&smp->tail, tail);
- atomic_store(&smp->nodes[1].next, next);
+ atomic_store(&q->head, head);
+ atomic_store(&q->tail, tail);
+ atomic_store(&q->nodes[1].next, next);
/* initialize avail list */
for (i = 2; i < MAX_NODES; i++) {
next = MAKE_POINTER(i + 1, 0);
- atomic_store(&smp->nodes[i].next, next);
+ atomic_store(&q->nodes[i].next, next);
}
next = MAKE_POINTER(0, 0); // (NULL, 0)
- atomic_store(&smp->nodes[MAX_NODES].next, next);
+ atomic_store(&q->nodes[MAX_NODES].next, next);
}
-void enqueue(unsigned int val)
+void enqueue(queue_t *q, unsigned int val)
{
- unsigned int success = 0;
+ int success = 0;
unsigned int node;
pointer tail;
pointer next;
pointer tmp;
node = new_node();
- smp->nodes[node].value = val;
- tmp = atomic_load(&smp->nodes[node].next);
+ q->nodes[node].value = val;
+ tmp = atomic_load(&q->nodes[node].next);
set_ptr(&tmp, 0); // NULL
- atomic_store(&smp->nodes[node].next, tmp);
+ atomic_store(&q->nodes[node].next, tmp);
while (!success) {
- tail = atomic_load(&smp->tail);
- next = atomic_load(&smp->nodes[get_ptr(tail)].next);
- if (tail == atomic_load(&smp->tail)) {
+ tail = atomic_load(&q->tail);
+ next = atomic_load(&q->nodes[get_ptr(tail)].next);
+ if (tail == atomic_load(&q->tail)) {
if (get_ptr(next) == 0) { // == NULL
pointer val = MAKE_POINTER(node, get_count(next) + 1);
- success = atomic_compare_exchange_weak(&smp->nodes[get_ptr(tail)].next,
+ success = atomic_compare_exchange_weak(&q->nodes[get_ptr(tail)].next,
&next,
val);
}
if (!success) {
- unsigned int ptr = get_ptr(atomic_load(&smp->nodes[get_ptr(tail)].next));
+ unsigned int ptr = get_ptr(atomic_load(&q->nodes[get_ptr(tail)].next));
pointer val = MAKE_POINTER(ptr,
get_count(tail) + 1);
- atomic_compare_exchange_strong(&smp->tail,
+ atomic_compare_exchange_strong(&q->tail,
&tail,
val);
thrd_yield();
}
}
}
- atomic_compare_exchange_strong(&smp->tail,
+ atomic_compare_exchange_strong(&q->tail,
&tail,
MAKE_POINTER(node, get_count(tail) + 1));
}
-unsigned int dequeue()
+unsigned int dequeue(queue_t *q)
{
unsigned int value;
- unsigned int success;
+ int success = 0;
pointer head;
pointer tail;
pointer next;
- for (success = FALSE; success == FALSE; ) {
- head = atomic_load(&smp->head);
- tail = atomic_load(&smp->tail);
- next = atomic_load(&smp->nodes[get_ptr(head)].next);
- if (atomic_load(&smp->head) == head) {
+ while (!success) {
+ head = atomic_load(&q->head);
+ tail = atomic_load(&q->tail);
+ next = atomic_load(&q->nodes[get_ptr(head)].next);
+ if (atomic_load(&q->head) == head) {
if (get_ptr(head) == get_ptr(tail)) {
if (get_ptr(next) == 0) { // NULL
return 0; // NULL
}
- atomic_compare_exchange_weak(&smp->tail,
+ atomic_compare_exchange_weak(&q->tail,
&tail,
MAKE_POINTER(get_ptr(next), get_count(tail) + 1));
thrd_yield();
} else {
- value = smp->nodes[get_ptr(next)].value;
- success = atomic_compare_exchange_weak(&smp->head,
+ value = q->nodes[get_ptr(next)].value;
+ success = atomic_compare_exchange_weak(&q->head,
&head,
MAKE_POINTER(get_ptr(next), get_count(head) + 1));
- if (success == FALSE) {
+ if (!success)
thrd_yield();
- }
}
}
}