-#include "main.h"
+#include <threads.h>
+#include <stdlib.h>
+#include "librace.h"
-extern unsigned pid;
-extern unsigned iterations;
-extern unsigned initial_nodes;
-extern private_t private;
-extern shared_mem_t* smp;
+#include "my_queue.h"
-void init_private()
-{
- private.node = 2 + initial_nodes + pid;
- private.value = 1 + initial_nodes + (pid * iterations);
+#define relaxed memory_order_relaxed
+#define release memory_order_release
+#define acquire memory_order_acquire
-}
+static unsigned int *node_nums;
-void init_memory()
+static unsigned int new_node()
{
+ return node_nums[get_thread_num()];
}
-static unsigned new_node()
+static void reclaim(unsigned int node)
{
- return private.node;
+ node_nums[get_thread_num()] = node;
}
-static void reclaim(unsigned node)
+void init_queue(queue_t *q, int num_threads)
{
- private.node = node;
-}
+ unsigned int i;
+ pointer head;
+ pointer tail;
+ pointer next;
-void init_queue()
-{
- unsigned i;
+ node_nums = malloc(num_threads * sizeof(*node_nums));
+ for (i = 0; i < num_threads; i++)
+ node_nums[i] = 2 + i;
/* initialize queue */
- smp->head.sep.ptr = 1;
- smp->head.sep.count = 0;
- smp->tail.sep.ptr = 1;
- smp->tail.sep.count = 0;
- smp->nodes[1].next.sep.ptr = NULL;
- smp->nodes[1].next.sep.count = 0;
+ head = MAKE_POINTER(1, 0);
+ tail = MAKE_POINTER(1, 0);
+ next = MAKE_POINTER(0, 0); // (NULL, 0)
+
+ atomic_init(&q->head, head);
+ atomic_init(&q->tail, tail);
+ atomic_init(&q->nodes[1].next, next);
/* initialize avail list */
- for (i=2; i<MAX_NODES; i++) {
- smp->nodes[i].next.sep.ptr = i+1;
- smp->nodes[i].next.sep.count = 0;
- }
- smp->nodes[MAX_NODES].next.sep.ptr = NULL;
- smp->nodes[MAX_NODES].next.sep.count = 0;
-
- /* initialize queue contents */
- if (initial_nodes > 0) {
- for (i=2; i<initial_nodes+2; i++) {
- smp->nodes[i].value = i;
- smp->nodes[i-1].next.sep.ptr = i;
- smp->nodes[i].next.sep.ptr = NULL;
- }
- smp->head.sep.ptr = 1;
- smp->tail.sep.ptr = 1 + initial_nodes;
+ for (i = 2; i < MAX_NODES; i++) {
+ next = MAKE_POINTER(i + 1, 0);
+ atomic_init(&q->nodes[i].next, next);
}
+
+ next = MAKE_POINTER(0, 0); // (NULL, 0)
+ atomic_init(&q->nodes[MAX_NODES].next, next);
}
-void enqueue(unsigned val)
+void enqueue(queue_t *q, unsigned int val)
{
- unsigned success;
- unsigned node;
- pointer_t tail;
- pointer_t next;
+ int success = 0;
+ unsigned int node;
+ pointer tail;
+ pointer next;
+ pointer tmp;
node = new_node();
- smp->nodes[node].value = val;
- smp->nodes[node].next.sep.ptr = NULL;
-
- for (success = FALSE; success == FALSE; ) {
- tail.con = smp->tail.con;
- next.con = smp->nodes[tail.sep.ptr].next.con;
- if (tail.con == smp->tail.con) {
- if (next.sep.ptr == NULL) {
- success = cas(&smp->nodes[tail.sep.ptr].next,
- next.con,
- MAKE_LONG(node, next.sep.count+1));
+ store_32(&q->nodes[node].value, val);
+ tmp = atomic_load_explicit(&q->nodes[node].next, relaxed);
+ set_ptr(&tmp, 0); // NULL
+ atomic_store_explicit(&q->nodes[node].next, tmp, relaxed);
+
+ while (!success) {
+ tail = atomic_load_explicit(&q->tail, acquire);
+ next = atomic_load_explicit(&q->nodes[get_ptr(tail)].next, acquire);
+ if (tail == atomic_load_explicit(&q->tail, relaxed)) {
+ if (get_ptr(next) == 0) { // == NULL
+ pointer value = MAKE_POINTER(node, get_count(next) + 1);
+ success = atomic_compare_exchange_strong_explicit(&q->nodes[get_ptr(tail)].next,
+ &next, value, memory_order_acq_rel, memory_order_acq_rel);
}
- if (success == FALSE) {
- cas(&smp->tail,
- tail.con,
- MAKE_LONG(smp->nodes[tail.sep.ptr].next.sep.ptr,
- tail.sep.count+1));
+ if (!success) {
+ unsigned int ptr = get_ptr(atomic_load_explicit(&q->nodes[get_ptr(tail)].next, memory_order_seq_cst));
+ pointer value = MAKE_POINTER(ptr,
+ get_count(tail) + 1);
+ atomic_compare_exchange_strong_explicit(&q->tail,
+ &tail, value,
+ memory_order_acq_rel, memory_order_acq_rel);
thrd_yield();
}
}
}
- cas(&smp->tail,
- tail.con,
- MAKE_LONG(node, tail.sep.count+1));
+ atomic_compare_exchange_strong_explicit(&q->tail,
+ &tail,
+ MAKE_POINTER(node, get_count(tail) + 1),
+ memory_order_acq_rel, memory_order_acq_rel);
}
-unsigned dequeue()
+unsigned int dequeue(queue_t *q)
{
- unsigned value;
- unsigned success;
- pointer_t head;
- pointer_t tail;
- pointer_t next;
-
- for (success = FALSE; success == FALSE; ) {
- head.con = smp->head.con;
- tail.con = smp->tail.con;
- next.con = smp->nodes[head.sep.ptr].next.con;
- if (smp->head.con == head.con) {
- if (head.sep.ptr == tail.sep.ptr) {
- if (next.sep.ptr == NULL) {
- return NULL;
+ unsigned int value;
+ int success = 0;
+ pointer head;
+ pointer tail;
+ pointer next;
+
+ while (!success) {
+ head = atomic_load_explicit(&q->head, acquire);
+ tail = atomic_load_explicit(&q->tail, acquire);
+ next = atomic_load_explicit(&q->nodes[get_ptr(head)].next, acquire);
+ if (atomic_load_explicit(&q->head, relaxed) == head) {
+ if (get_ptr(head) == get_ptr(tail)) {
+ if (get_ptr(next) == 0) { // NULL
+ return 0; // NULL
}
- cas(&smp->tail,
- tail.con,
- MAKE_LONG(next.sep.ptr, tail.sep.count+1));
+ atomic_compare_exchange_strong_explicit(&q->tail,
+ &tail,
+ MAKE_POINTER(get_ptr(next), get_count(tail) + 1),
+ memory_order_acq_rel, memory_order_acq_rel);
thrd_yield();
} else {
- value = smp->nodes[next.sep.ptr].value;
- success = cas(&smp->head,
- head.con,
- MAKE_LONG(next.sep.ptr, head.sep.count+1));
- if (success == FALSE) {
+ value = load_32(&q->nodes[get_ptr(next)].value);
+ success = atomic_compare_exchange_strong_explicit(&q->head,
+ &head,
+ MAKE_POINTER(get_ptr(next), get_count(head) + 1),
+ memory_order_acq_rel, memory_order_acq_rel);
+ if (!success)
thrd_yield();
- }
}
}
}
- reclaim(head.sep.ptr);
+ reclaim(get_ptr(head));
return value;
}