X-Git-Url: http://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=rculfhash.c;h=675ef382311beafcbb8d62ad284b2032d6db79aa;hp=b67acc820a078011f81963608f7c366fc1a3d2ec;hb=5488222bbdb95680d942c3fb645095b48e96620f;hpb=238cc06e5728e3a642d4d22bd4fc199cfd265110

diff --git a/rculfhash.c b/rculfhash.c
index b67acc8..675ef38 100644
--- a/rculfhash.c
+++ b/rculfhash.c
@@ -241,6 +241,8 @@ struct cds_lfht {
 	struct rcu_table t;
 	cds_lfht_hash_fct hash_fct;
 	cds_lfht_compare_fct compare_fct;
+	unsigned long min_alloc_order;
+	unsigned long min_alloc_size;
 	unsigned long hash_seed;
 	int flags;
 	/*
@@ -871,12 +873,6 @@ void _cds_lfht_add(struct cds_lfht *ht,
 
 	assert(!is_dummy(node));
 	assert(!is_removed(node));
-	if (!size) {
-		assert(dummy);
-		assert(!unique_ret);
-		node->p.next = flag_dummy(get_end());
-		return;		/* Initial first add (head) */
-	}
 	lookup = lookup_bucket(ht, size, bit_reverse_ulong(node->p.reverse_hash));
 	for (;;) {
 		uint32_t chain_len = 0;
@@ -1084,16 +1080,17 @@ void init_table_populate_partition(struct cds_lfht *ht, unsigned long i,
 {
 	unsigned long j;
 
+	assert(i > ht->min_alloc_order);
 	ht->cds_lfht_rcu_read_lock();
 	for (j = start; j < start + len; j++) {
 		struct cds_lfht_node *new_node =
 			(struct cds_lfht_node *) &ht->t.tbl[i]->nodes[j];
 
 		dbg_printf("init populate: i %lu j %lu hash %lu\n",
-			   i, j, !i ? 0 : (1UL << (i - 1)) + j);
+			   i, j, (1UL << (i - 1)) + j);
 		new_node->p.reverse_hash =
-			bit_reverse_ulong(!i ? 0 : (1UL << (i - 1)) + j);
-		_cds_lfht_add(ht, !i ? 0 : (1UL << (i - 1)),
+				bit_reverse_ulong((1UL << (i - 1)) + j);
+		_cds_lfht_add(ht, 1UL << (i - 1),
 				new_node, NULL, 1);
 	}
 	ht->cds_lfht_rcu_read_unlock();
@@ -1121,14 +1118,15 @@ void init_table(struct cds_lfht *ht,
 
 	dbg_printf("init table: first_order %lu last_order %lu\n",
 		   first_order, last_order);
+	assert(first_order > ht->min_alloc_order);
 	for (i = first_order; i <= last_order; i++) {
 		unsigned long len;
 
-		len = !i ? 1 : 1UL << (i - 1);
+		len = 1UL << (i - 1);
 		dbg_printf("init order %lu len: %lu\n", i, len);
 
 		/* Stop expand if the resize target changes under us */
-		if (CMM_LOAD_SHARED(ht->t.resize_target) < (!i ? 1 : (1UL << i)))
+		if (CMM_LOAD_SHARED(ht->t.resize_target) < (1UL << i))
 			break;
 
 		ht->t.tbl[i] = calloc(1, len * sizeof(struct _cds_lfht_node));
@@ -1144,9 +1142,9 @@ void init_table(struct cds_lfht *ht,
 		 * Update table size.
 		 */
 		cmm_smp_wmb();	/* populate data before RCU size */
-		CMM_STORE_SHARED(ht->t.size, !i ? 1 : (1UL << i));
+		CMM_STORE_SHARED(ht->t.size, 1UL << i);
 
-		dbg_printf("init new size: %lu\n", !i ? 1 : (1UL << i));
+		dbg_printf("init new size: %lu\n", 1UL << i);
 		if (CMM_LOAD_SHARED(ht->in_progress_destroy))
 			break;
 	}
@@ -1183,17 +1181,17 @@ void remove_table_partition(struct cds_lfht *ht, unsigned long i,
 {
 	unsigned long j;
 
+	assert(i > ht->min_alloc_order);
 	ht->cds_lfht_rcu_read_lock();
 	for (j = start; j < start + len; j++) {
 		struct cds_lfht_node *fini_node =
 			(struct cds_lfht_node *) &ht->t.tbl[i]->nodes[j];
 
 		dbg_printf("remove entry: i %lu j %lu hash %lu\n",
-			   i, j, !i ? 0 : (1UL << (i - 1)) + j);
+			   i, j, (1UL << (i - 1)) + j);
 		fini_node->p.reverse_hash =
-			bit_reverse_ulong(!i ? 0 : (1UL << (i - 1)) + j);
-		(void) _cds_lfht_del(ht, !i ? 0 : (1UL << (i - 1)),
-				fini_node, 1);
+			bit_reverse_ulong((1UL << (i - 1)) + j);
+		(void) _cds_lfht_del(ht, 1UL << (i - 1), fini_node, 1);
 	}
 	ht->cds_lfht_rcu_read_unlock();
 }
@@ -1221,11 +1219,11 @@ void fini_table(struct cds_lfht *ht,
 
 	dbg_printf("fini table: first_order %lu last_order %lu\n",
 		   first_order, last_order);
-	assert(first_order > 0);
+	assert(first_order > ht->min_alloc_order);
 	for (i = last_order; i >= first_order; i--) {
 		unsigned long len;
 
-		len = !i ? 1 : 1UL << (i - 1);
+		len = 1UL << (i - 1);
 		dbg_printf("fini order %lu len: %lu\n", i, len);
 
 		/* Stop shrink if the resize target changes under us */
@@ -1266,10 +1264,54 @@ void fini_table(struct cds_lfht *ht,
 	}
 }
 
+static
+void cds_lfht_create_dummy(struct cds_lfht *ht, unsigned long size)
+{
+	struct _cds_lfht_node *prev, *node;
+	unsigned long order, len, i, j;
+
+	ht->t.tbl[0] = calloc(1, ht->min_alloc_size * sizeof(struct _cds_lfht_node));
+	assert(ht->t.tbl[0]);
+
+	dbg_printf("create dummy: order %lu index %lu hash %lu\n", 0, 0, 0);
+	ht->t.tbl[0]->nodes[0].next = flag_dummy(get_end());
+	ht->t.tbl[0]->nodes[0].reverse_hash = 0;
+
+	for (order = 1; order < get_count_order_ulong(size) + 1; order++) {
+		len = 1UL << (order - 1);
+		if (order <= ht->min_alloc_order) {
+			ht->t.tbl[order] = (void *)(ht->t.tbl[0]->nodes + len);
+		} else {
+			ht->t.tbl[order] = calloc(1, len * sizeof(struct _cds_lfht_node));
+			assert(ht->t.tbl[order]);
+		}
+
+		i = 0;
+		prev = ht->t.tbl[i]->nodes;
+		for (j = 0; j < len; j++) {
+			if (j & (j - 1)) {	/* Between power of 2 */
+				prev++;
+			} else if (j) {		/* At each power of 2 */
+				i++;
+				prev = ht->t.tbl[i]->nodes;
+			}
+
+			node = &ht->t.tbl[order]->nodes[j];
+			dbg_printf("create dummy: order %lu index %lu hash %lu\n",
+				   order, j, j + len);
+			node->next = prev->next;
+			assert(is_dummy(node->next));
+			node->reverse_hash = bit_reverse_ulong(j + len);
+			prev->next = flag_dummy((struct cds_lfht_node *)node);
+		}
+	}
+}
+
 struct cds_lfht *_cds_lfht_new(cds_lfht_hash_fct hash_fct,
 			cds_lfht_compare_fct compare_fct,
 			unsigned long hash_seed,
 			unsigned long init_size,
+			unsigned long min_alloc_size,
 			int flags,
 			void (*cds_lfht_call_rcu)(struct rcu_head *head,
 					void (*func)(struct rcu_head *head)),
@@ -1285,9 +1327,14 @@ struct cds_lfht *_cds_lfht_new(cds_lfht_hash_fct hash_fct,
 	struct cds_lfht *ht;
 	unsigned long order;
 
+	/* min_alloc_size must be power of two */
+	if (!min_alloc_size || (min_alloc_size & (min_alloc_size - 1)))
+		return NULL;
 	/* init_size must be power of two */
-	if (init_size && (init_size & (init_size - 1)))
+	if (!init_size || (init_size & (init_size - 1)))
 		return NULL;
+	min_alloc_size = max(min_alloc_size, MIN_TABLE_SIZE);
+	init_size = max(init_size, min_alloc_size);
 	ht = calloc(1, sizeof(struct cds_lfht));
 	assert(ht);
 	ht->hash_fct = hash_fct;
@@ -1305,14 +1352,13 @@ struct cds_lfht *_cds_lfht_new(cds_lfht_hash_fct hash_fct,
 	ht->percpu_count = alloc_per_cpu_items_count();
 	/* this mutex should not nest in read-side C.S. */
 	pthread_mutex_init(&ht->resize_mutex, NULL);
-	order = get_count_order_ulong(max(init_size, MIN_TABLE_SIZE));
 	ht->flags = flags;
-	ht->cds_lfht_rcu_thread_offline();
-	pthread_mutex_lock(&ht->resize_mutex);
+	order = get_count_order_ulong(init_size);
 	ht->t.resize_target = 1UL << order;
-	init_table(ht, 0, order);
-	pthread_mutex_unlock(&ht->resize_mutex);
-	ht->cds_lfht_rcu_thread_online();
+	cds_lfht_create_dummy(ht, 1UL << order);
+	ht->t.size = 1UL << order;
+	ht->min_alloc_size = min_alloc_size;
+	ht->min_alloc_order = get_count_order_ulong(min_alloc_size);
 	return ht;
 }
 
@@ -1530,7 +1576,12 @@ int cds_lfht_delete_dummy(struct cds_lfht *ht)
 				bit_reverse_ulong(ht->t.tbl[order]->nodes[i].reverse_hash));
 			assert(is_dummy(ht->t.tbl[order]->nodes[i].next));
 		}
-		poison_free(ht->t.tbl[order]);
+
+		if (order == ht->min_alloc_order)
+			poison_free(ht->t.tbl[0]);
+		else if (order > ht->min_alloc_order)
+			poison_free(ht->t.tbl[order]);
+		/* Nothing to delete for order < ht->min_alloc_order */
 	}
 	return 0;
 }
@@ -1631,7 +1682,7 @@ void _do_cds_lfht_shrink(struct cds_lfht *ht,
 {
 	unsigned long old_order, new_order;
 
-	new_size = max(new_size, MIN_TABLE_SIZE);
+	new_size = max(new_size, ht->min_alloc_size);
 	old_order = get_count_order_ulong(old_size);
 	new_order = get_count_order_ulong(new_size);
 	dbg_printf("resize from %lu (order %lu) to %lu (order %lu) buckets\n",
@@ -1681,7 +1732,7 @@ static
 void resize_target_update_count(struct cds_lfht *ht,
 				unsigned long count)
 {
-	count = max(count, MIN_TABLE_SIZE);
+	count = max(count, ht->min_alloc_size);
 	uatomic_set(&ht->t.resize_target, count);
 }