} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
struct rcu_level {
- struct rcu_head head;
+ /* Note: manually update allocation length when adding a field */
struct _cds_lfht_node nodes[0];
};
};
struct partition_resize_work {
- struct rcu_head head;
+ pthread_t thread_id;
struct cds_lfht *ht;
unsigned long i, start, len;
void (*fct)(struct cds_lfht *ht, unsigned long i,
unsigned long start, unsigned long len);
};
-enum add_mode {
- ADD_DEFAULT = 0,
- ADD_UNIQUE = 1,
- ADD_REPLACE = 2,
-};
-
static
-struct cds_lfht_node *_cds_lfht_add(struct cds_lfht *ht,
- unsigned long size,
- struct cds_lfht_node *node,
- enum add_mode mode, int dummy);
+void _cds_lfht_add(struct cds_lfht *ht,
+ unsigned long size,
+ struct cds_lfht_node *node,
+ struct cds_lfht_iter *unique_ret,
+ int dummy);
/*
* Algorithm to reverse bits in a word by lookup table, extended to
#endif
}
+/*
+ * Return the minimum order for which x <= (1UL << order).
+ * Return -1 if x is 0.
+ */
int get_count_order_u32(uint32_t x)
{
- int order;
+ if (!x)
+ return -1;
- order = fls_u32(x) - 1;
- if (x & (x - 1))
- order++;
- return order;
+ return fls_u32(x - 1);
}
+/*
+ * Return the minimum order for which x <= (1UL << order).
+ * Return -1 if x is 0.
+ */
int get_count_order_ulong(unsigned long x)
{
- int order;
+ if (!x)
+ return -1;
- order = fls_ulong(x) - 1;
- if (x & (x - 1))
- order++;
- return order;
+ return fls_ulong(x - 1);
}
#ifdef POISON_FREE
}
static
-void cds_lfht_free_level(struct rcu_head *head)
+struct _cds_lfht_node *lookup_bucket(struct cds_lfht *ht, unsigned long size,
+ unsigned long hash)
{
- struct rcu_level *l =
- caa_container_of(head, struct rcu_level, head);
- poison_free(l);
+ unsigned long index, order;
+
+ assert(size > 0);
+ index = hash & (size - 1);
+ /*
+ * equivalent to get_count_order_ulong(index + 1), but optimizes
+ * away the non-existing 0 special-case for
+ * get_count_order_ulong.
+ */
+ order = fls_ulong(index);
+
+ dbg_printf("lookup hash %lu index %lu order %lu aridx %lu\n",
+ hash, index, order, index & (!order ? 0 : ((1UL << (order - 1)) - 1)));
+
+ return &ht->t.tbl[order]->nodes[index & (!order ? 0 : ((1UL << (order - 1)) - 1))];
}
/*
iter_prev = dummy;
/* We can always skip the dummy node initially */
iter = rcu_dereference(iter_prev->p.next);
+ assert(!is_removed(iter));
assert(iter_prev->p.reverse_hash <= node->p.reverse_hash);
/*
* We should never be called with dummy (start of chain)
new_next = flag_dummy(clear_flag(next));
else
new_next = clear_flag(next);
- if (is_removed(iter))
- new_next = flag_removed(new_next);
(void) uatomic_cmpxchg(&iter_prev->p.next, iter, new_next);
}
return;
static
int _cds_lfht_replace(struct cds_lfht *ht, unsigned long size,
struct cds_lfht_node *old_node,
- struct cds_lfht_node *ret_next,
+ struct cds_lfht_node *old_next,
struct cds_lfht_node *new_node)
{
- struct cds_lfht_node *dummy, *old_next;
+ struct cds_lfht_node *dummy, *ret_next;
struct _cds_lfht_node *lookup;
int flagged = 0;
- unsigned long hash, index, order;
if (!old_node) /* Return -ENOENT if asked to replace NULL node */
goto end;
assert(!is_removed(new_node));
assert(!is_dummy(new_node));
assert(new_node != old_node);
- do {
+ for (;;) {
/* Insert after node to be replaced */
- old_next = ret_next;
if (is_removed(old_next)) {
/*
* Too late, the old node has been removed under us
*/
ret_next = uatomic_cmpxchg(&old_node->p.next,
old_next, flag_removed(new_node));
- } while (ret_next != old_next);
+ if (ret_next == old_next)
+ break;
+ old_next = ret_next;
+ }
/* We performed the replacement. */
flagged = 1;
* lookup for the node, and remove it (along with any other
* logically removed node) if found.
*/
- hash = bit_reverse_ulong(old_node->p.reverse_hash);
- assert(size > 0);
- index = hash & (size - 1);
- order = get_count_order_ulong(index + 1);
- lookup = &ht->t.tbl[order]->nodes[index & (!order ? 0 : ((1UL << (order - 1)) - 1))];
+ lookup = lookup_bucket(ht, size, bit_reverse_ulong(old_node->p.reverse_hash));
dummy = (struct cds_lfht_node *) lookup;
_cds_lfht_gc_bucket(dummy, new_node);
end:
}
}
+/*
+ * A non-NULL unique_ret pointer uses the "add unique" (or uniquify) add
+ * mode. A NULL unique_ret allows creation of duplicate keys.
+ */
static
-struct cds_lfht_node *_cds_lfht_add(struct cds_lfht *ht,
- unsigned long size,
- struct cds_lfht_node *node,
- enum add_mode mode, int dummy)
+void _cds_lfht_add(struct cds_lfht *ht,
+ unsigned long size,
+ struct cds_lfht_node *node,
+ struct cds_lfht_iter *unique_ret,
+ int dummy)
{
struct cds_lfht_node *iter_prev, *iter, *next, *new_node, *new_next,
- *dummy_node, *return_node;
+ *return_node;
struct _cds_lfht_node *lookup;
- unsigned long hash, index, order;
assert(!is_dummy(node));
assert(!is_removed(node));
if (!size) {
assert(dummy);
+ assert(!unique_ret);
node->p.next = flag_dummy(get_end());
- return node; /* Initial first add (head) */
+ return; /* Initial first add (head) */
}
- hash = bit_reverse_ulong(node->p.reverse_hash);
+ lookup = lookup_bucket(ht, size, bit_reverse_ulong(node->p.reverse_hash));
for (;;) {
uint32_t chain_len = 0;
* iter_prev points to the non-removed node prior to the
* insert location.
*/
- index = hash & (size - 1);
- order = get_count_order_ulong(index + 1);
- lookup = &ht->t.tbl[order]->nodes[index & ((!order ? 0 : (1UL << (order - 1))) - 1)];
iter_prev = (struct cds_lfht_node *) lookup;
/* We can always skip the dummy node initially */
iter = rcu_dereference(iter_prev->p.next);
goto insert;
if (likely(clear_flag(iter)->p.reverse_hash > node->p.reverse_hash))
goto insert;
+ /* dummy node is the first node of the identical-hash-value chain */
+ if (dummy && clear_flag(iter)->p.reverse_hash == node->p.reverse_hash)
+ goto insert;
next = rcu_dereference(clear_flag(iter)->p.next);
if (unlikely(is_removed(next)))
goto gc_node;
- if ((mode == ADD_UNIQUE || mode == ADD_REPLACE)
+ if (unique_ret
&& !is_dummy(next)
+ && clear_flag(iter)->p.reverse_hash == node->p.reverse_hash
&& !ht->compare_fct(node->key, node->key_len,
clear_flag(iter)->key,
clear_flag(iter)->key_len)) {
- if (mode == ADD_UNIQUE)
- return clear_flag(iter);
- else /* mode == ADD_REPLACE */
- goto replace;
+ unique_ret->node = clear_flag(iter);
+ unique_ret->next = next;
+ return;
}
/* Only account for identical reverse hash once */
if (iter_prev->p.reverse_hash != clear_flag(iter)->p.reverse_hash
new_node) != iter) {
continue; /* retry */
} else {
- if (mode == ADD_REPLACE)
- return_node = NULL;
- else /* ADD_DEFAULT and ADD_UNIQUE */
- return_node = node;
- goto gc_end;
- }
-
- replace:
-
- if (!_cds_lfht_replace(ht, size, clear_flag(iter), next,
- node)) {
- return_node = clear_flag(iter);
- goto end; /* gc already done */
- } else {
- continue; /* retry */
+ return_node = node;
+ goto end;
}
gc_node:
(void) uatomic_cmpxchg(&iter_prev->p.next, iter, new_next);
/* retry */
}
-gc_end:
- /* Garbage collect logically removed nodes in the bucket */
- index = hash & (size - 1);
- order = get_count_order_ulong(index + 1);
- lookup = &ht->t.tbl[order]->nodes[index & (!order ? 0 : ((1UL << (order - 1)) - 1))];
- dummy_node = (struct cds_lfht_node *) lookup;
- _cds_lfht_gc_bucket(dummy_node, node);
end:
- return return_node;
+ if (unique_ret) {
+ unique_ret->node = return_node;
+ /* unique_ret->next left unset, never used. */
+ }
}
static
struct cds_lfht_node *dummy, *next, *old;
struct _cds_lfht_node *lookup;
int flagged = 0;
- unsigned long hash, index, order;
if (!node) /* Return -ENOENT if asked to delete NULL node */
goto end;
* the node, and remove it (along with any other logically removed node)
* if found.
*/
- hash = bit_reverse_ulong(node->p.reverse_hash);
- assert(size > 0);
- index = hash & (size - 1);
- order = get_count_order_ulong(index + 1);
- lookup = &ht->t.tbl[order]->nodes[index & (!order ? 0 : ((1UL << (order - 1)) - 1))];
+ lookup = lookup_bucket(ht, size, bit_reverse_ulong(node->p.reverse_hash));
dummy = (struct cds_lfht_node *) lookup;
_cds_lfht_gc_bucket(dummy, node);
end:
struct partition_resize_work *work;
int thread, ret;
unsigned long nr_threads;
- pthread_t *thread_id;
/*
* Note: nr_cpus_mask + 1 is always power of 2.
}
partition_len = len >> get_count_order_ulong(nr_threads);
work = calloc(nr_threads, sizeof(*work));
- thread_id = calloc(nr_threads, sizeof(*thread_id));
assert(work);
for (thread = 0; thread < nr_threads; thread++) {
work[thread].ht = ht;
work[thread].len = partition_len;
work[thread].start = thread * partition_len;
work[thread].fct = fct;
- ret = pthread_create(&thread_id[thread], ht->resize_attr,
+ ret = pthread_create(&(work[thread].thread_id), ht->resize_attr,
partition_resize_thread, &work[thread]);
assert(!ret);
}
for (thread = 0; thread < nr_threads; thread++) {
- ret = pthread_join(thread_id[thread], NULL);
+ ret = pthread_join(work[thread].thread_id, NULL);
assert(!ret);
}
free(work);
- free(thread_id);
}
/*
i, j, !i ? 0 : (1UL << (i - 1)) + j);
new_node->p.reverse_hash =
bit_reverse_ulong(!i ? 0 : (1UL << (i - 1)) + j);
- (void) _cds_lfht_add(ht, !i ? 0 : (1UL << (i - 1)),
- new_node, ADD_DEFAULT, 1);
+ _cds_lfht_add(ht, !i ? 0 : (1UL << (i - 1)),
+ new_node, NULL, 1);
}
ht->cds_lfht_rcu_read_unlock();
}
if (CMM_LOAD_SHARED(ht->t.resize_target) < (!i ? 1 : (1UL << i)))
break;
- ht->t.tbl[i] = calloc(1, sizeof(struct rcu_level)
- + (len * sizeof(struct _cds_lfht_node)));
+ ht->t.tbl[i] = calloc(1, len * sizeof(struct _cds_lfht_node));
assert(ht->t.tbl[i]);
/*
unsigned long first_order, unsigned long len_order)
{
long i, end_order;
+ void *free_by_rcu = NULL;
dbg_printf("fini table: first_order %lu end_order %lu\n",
first_order, first_order + len_order);
* return a logically removed node as insert position.
*/
ht->cds_lfht_synchronize_rcu();
+ if (free_by_rcu)
+ free(free_by_rcu);
/*
* Set "removed" flag in dummy nodes about to be removed.
*/
remove_table(ht, i, len);
- ht->cds_lfht_call_rcu(&ht->t.tbl[i]->head, cds_lfht_free_level);
+ free_by_rcu = ht->t.tbl[i];
dbg_printf("fini new size: %lu\n", 1UL << i);
if (CMM_LOAD_SHARED(ht->in_progress_destroy))
break;
}
+
+ if (free_by_rcu) {
+ ht->cds_lfht_synchronize_rcu();
+ free(free_by_rcu);
+ }
}
struct cds_lfht *_cds_lfht_new(cds_lfht_hash_fct hash_fct,
{
struct cds_lfht_node *node, *next, *dummy_node;
struct _cds_lfht_node *lookup;
- unsigned long hash, reverse_hash, index, order, size;
+ unsigned long hash, reverse_hash, size;
hash = ht->hash_fct(key, key_len, ht->hash_seed);
reverse_hash = bit_reverse_ulong(hash);
size = rcu_dereference(ht->t.size);
- index = hash & (size - 1);
- order = get_count_order_ulong(index + 1);
- lookup = &ht->t.tbl[order]->nodes[index & (!order ? 0 : ((1UL << (order - 1))) - 1)];
- dbg_printf("lookup hash %lu index %lu order %lu aridx %lu\n",
- hash, index, order, index & (!order ? 0 : ((1UL << (order - 1)) - 1)));
+ lookup = lookup_bucket(ht, size, hash);
dummy_node = (struct cds_lfht_node *) lookup;
/* We can always skip the dummy node initially */
node = rcu_dereference(dummy_node->p.next);
next = rcu_dereference(node->p.next);
if (likely(!is_removed(next))
&& !is_dummy(next)
+ && clear_flag(node)->p.reverse_hash == reverse_hash
&& likely(!ht->compare_fct(node->key, node->key_len, key, key_len))) {
break;
}
node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
size = rcu_dereference(ht->t.size);
- (void) _cds_lfht_add(ht, size, node, ADD_DEFAULT, 0);
+ _cds_lfht_add(ht, size, node, NULL, 0);
ht_count_add(ht, size);
}
struct cds_lfht_node *node)
{
unsigned long hash, size;
- struct cds_lfht_node *ret;
+ struct cds_lfht_iter iter;
hash = ht->hash_fct(node->key, node->key_len, ht->hash_seed);
node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
size = rcu_dereference(ht->t.size);
- ret = _cds_lfht_add(ht, size, node, ADD_UNIQUE, 0);
- if (ret == node)
+ _cds_lfht_add(ht, size, node, &iter, 0);
+ if (iter.node == node)
ht_count_add(ht, size);
- return ret;
+ return iter.node;
}
struct cds_lfht_node *cds_lfht_add_replace(struct cds_lfht *ht,
struct cds_lfht_node *node)
{
unsigned long hash, size;
- struct cds_lfht_node *ret;
+ struct cds_lfht_iter iter;
hash = ht->hash_fct(node->key, node->key_len, ht->hash_seed);
node->p.reverse_hash = bit_reverse_ulong((unsigned long) hash);
size = rcu_dereference(ht->t.size);
- ret = _cds_lfht_add(ht, size, node, ADD_REPLACE, 0);
- if (ret == NULL)
- ht_count_add(ht, size);
- return ret;
+ for (;;) {
+ _cds_lfht_add(ht, size, node, &iter, 0);
+ if (iter.node == node) {
+ ht_count_add(ht, size);
+ return NULL;
+ }
+
+ if (!_cds_lfht_replace(ht, size, iter.node, iter.next, node))
+ return iter.node;
+ }
}
int cds_lfht_replace(struct cds_lfht *ht, struct cds_lfht_iter *old_iter,
old_order = get_count_order_ulong(old_size) + 1;
new_order = get_count_order_ulong(new_size) + 1;
- printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
- old_size, old_order, new_size, new_order);
+ dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
+ old_size, old_order, new_size, new_order);
assert(new_size > old_size);
init_table(ht, old_order, new_order - old_order);
}
new_size = max(new_size, MIN_TABLE_SIZE);
old_order = get_count_order_ulong(old_size) + 1;
new_order = get_count_order_ulong(new_size) + 1;
- printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
- old_size, old_order, new_size, new_order);
+ dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
+ old_size, old_order, new_size, new_order);
assert(new_size < old_size);
/* Remove and unlink all dummy nodes to remove. */
projects / urcu.git / blobdiff