#include "list.h"
#include "mem.h"
-typedef struct node {
- void *key;
- uint64_t val;
- struct node *next;
-} node_t;
+typedef struct ll_iter node_t;
+
+struct ll_iter {
+ map_key_t key;
+ map_val_t val;
+ node_t *next;
+};
struct ll {
node_t *head;
const datatype_t *key_type;
};
-static node_t *node_alloc (void *key, uint64_t val) {
+static node_t *node_alloc (map_key_t key, map_val_t val) {
node_t *item = (node_t *)nbd_malloc(sizeof(node_t));
item->key = key;
item->val = val;
void ll_free (list_t *ll) {
node_t *item = ll->head->next;
while (item) {
- node_t *next = (node_t *)STRIP_TAG(item->next);
+ node_t *next = (node_t *)STRIP_TAG(item->next, TAG1);
nbd_free(item);
item = next;
}
uint64_t count = 0;
node_t *item = ll->head->next;
while (item) {
- count++;
- item = (node_t *)STRIP_TAG(item->next);
+ if (!IS_TAGGED(item->next, TAG1)) {
+ count++;
+ }
+ item = (node_t *)STRIP_TAG(item->next, TAG1);
}
return count;
}
-static int find_pred (node_t **pred_ptr, node_t **item_ptr, list_t *ll, void *key, int help_remove) {
+static int find_pred (node_t **pred_ptr, node_t **item_ptr, list_t *ll, map_key_t key, int help_remove) {
node_t *pred = ll->head;
node_t *item = pred->next;
TRACE("l2", "find_pred: searching for key %p in list (head is %p)", key, pred);
node_t *next = item->next;
// A tag means an item is logically removed but not physically unlinked yet.
- while (EXPECT_FALSE(IS_TAGGED(next))) {
+ while (EXPECT_FALSE(IS_TAGGED(next, TAG1))) {
// Skip over logically removed items.
if (!help_remove) {
- item = (node_t *)STRIP_TAG(item->next);
+ item = (node_t *)STRIP_TAG(item->next, TAG1);
if (EXPECT_FALSE(item == NULL))
break;
TRACE("l3", "find_pred: skipping marked item %p (next is %p)", item, next);
// Unlink logically removed items.
node_t *other;
TRACE("l3", "find_pred: unlinking marked item %p next is %p", item, next);
- if ((other = SYNC_CAS(&pred->next, item, STRIP_TAG(next))) == item) {
+ if ((other = SYNC_CAS(&pred->next, item, STRIP_TAG(next, TAG1))) == item) {
TRACE("l2", "find_pred: unlinked item %p from pred %p", item, pred);
- item = (node_t *)STRIP_TAG(next);
+ item = (node_t *)STRIP_TAG(next, TAG1);
if (EXPECT_FALSE(item == NULL))
break;
next = item->next;
} else {
TRACE("l2", "find_pred: lost a race to unlink item %p from pred %p", item, pred);
TRACE("l2", "find_pred: pred's link changed to %p", other, 0);
- if (IS_TAGGED(other))
+ if (IS_TAGGED(other, TAG1))
return find_pred(pred_ptr, item_ptr, ll, key, help_remove); // retry
item = other;
if (EXPECT_FALSE(item == NULL))
}
// Fast find. Do not help unlink partially removed nodes and do not return the found item's predecessor.
-uint64_t ll_lookup (list_t *ll, void *key) {
+map_val_t ll_lookup (list_t *ll, map_key_t key) {
TRACE("l1", "ll_lookup: searching for key %p in list %p", key, ll);
node_t *item;
int found = find_pred(NULL, &item, ll, key, FALSE);
// If we found an <item> matching the key return its value.
if (found) {
- uint64_t val = item->val;
+ map_val_t val = item->val;
if (val != DOES_NOT_EXIST) {
TRACE("l1", "ll_lookup: found item %p. val %p. returning item", item, item->val);
return val;
return DOES_NOT_EXIST;
}
-uint64_t ll_cas (list_t *ll, void *key, uint64_t expectation, uint64_t new_val) {
+map_val_t ll_cas (list_t *ll, map_key_t key, map_val_t expectation, map_val_t new_val) {
TRACE("l1", "ll_cas: key %p list %p", key, ll);
TRACE("l1", "ll_cas: expectation %p new value %p", expectation, new_val);
ASSERT((int64_t)new_val > 0);
// Create a new item and insert it into the list.
TRACE("l2", "ll_cas: attempting to insert item between %p and %p", pred, pred->next);
- void *new_key = (ll->key_type == NULL) ? key : ll->key_type->clone(key);
+ map_key_t new_key = (ll->key_type == NULL) ? key : ll->key_type->clone(key);
node_t *new_item = node_alloc(new_key, new_val);
node_t *next = new_item->next = old_item;
node_t *other = SYNC_CAS(&pred->next, next, new_item);
}
// Found an item in the list that matches the key.
- uint64_t old_item_val = old_item->val;
+ map_val_t old_item_val = old_item->val;
do {
// If the item's value is DOES_NOT_EXIST it means another thread removed the node out from under us.
if (EXPECT_FALSE(old_item_val == DOES_NOT_EXIST)) {
// replace DOES_NOT_EXIST with our value. Then another thread that is updating the value could think it
// succeeded and return our value even though we indicated that the node has been removed. If the CAS
// fails it means another thread either removed the node or updated its value.
- uint64_t ret_val = SYNC_CAS(&old_item->val, old_item_val, new_val);
+ map_val_t ret_val = SYNC_CAS(&old_item->val, old_item_val, new_val);
if (ret_val == old_item_val) {
TRACE("l1", "ll_cas: the CAS succeeded. updated the value of the item", 0, 0);
return ret_val; // success
} while (1);
}
-uint64_t ll_remove (list_t *ll, void *key) {
+map_val_t ll_remove (list_t *ll, map_key_t key) {
TRACE("l1", "ll_remove: removing item with key %p from list %p", key, ll);
node_t *pred;
node_t *item;
node_t *old_next = item->next;
do {
next = old_next;
- old_next = SYNC_CAS(&item->next, next, TAG_VALUE(next));
- if (IS_TAGGED(old_next)) {
+ old_next = SYNC_CAS(&item->next, next, TAG_VALUE(next, TAG1));
+ if (IS_TAGGED(old_next, TAG1)) {
TRACE("l1", "ll_remove: lost a race -- %p is already marked for removal by another thread", item, 0);
return DOES_NOT_EXIST;
}
} while (next != old_next);
TRACE("l2", "ll_remove: logically removed item %p", item, 0);
- ASSERT(IS_TAGGED(item->next));
+ ASSERT(IS_TAGGED(item->next, TAG1));
// Atomically swap out the item's value in case another thread is updating the item while we are
// removing it. This establishes which operation occurs first logically, the update or the remove.
- uint64_t val = SYNC_SWAP(&item->val, DOES_NOT_EXIST);
+ map_val_t val = SYNC_SWAP(&item->val, DOES_NOT_EXIST);
TRACE("l2", "ll_remove: replaced item's val %p with DOES_NOT_EXIT", val, 0);
// Unlink <item> from <ll>. If we lose a race to another thread just back off. It is safe to leave the
int i = 0;
while (item) {
node_t *next = item->next;
- if (IS_TAGGED(item)) {
+ if (IS_TAGGED(item, TAG1)) {
printf("*");
}
printf("%p:%p ", item, item->key);
fflush(stdout);
- item = (node_t *)STRIP_TAG(next);
+ item = (node_t *)STRIP_TAG(next, TAG1);
if (i++ > 30) {
printf("...");
break;
}
printf("\n");
}
+
+ll_iter_t *ll_iter_begin (list_t *ll, map_key_t key) {
+ node_t *iter = node_alloc(0,0);
+ find_pred(NULL, &iter->next, ll, key, FALSE);
+ return iter;
+}
+
+map_val_t ll_iter_next (ll_iter_t *iter, map_key_t *key_ptr) {
+ assert(iter);
+ node_t *item = iter->next;
+ while (item != NULL && IS_TAGGED(item->next, TAG1)) {
+ item = (node_t *)STRIP_TAG(item->next, TAG1);
+ }
+ if (item == NULL) {
+ iter->next = NULL;
+ return DOES_NOT_EXIST;
+ }
+ iter->next = item->next;
+ if (key_ptr != NULL) {
+ *key_ptr = item->key;
+ }
+ return item->val;
+}
+
+void ll_iter_free (ll_iter_t *iter) {
+ nbd_free(iter);
+}