X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=rculfhash.c;h=cd25d336aea3ef781456c046699ef86e2de81b92;hb=d933dd0e116eceb59b1df0f223e3962a1e51bfb3;hp=1487980c832c115154937cda4b185024636f9e44;hpb=b198f0fda77c816d80f63cfa2e71a7e0b4496736;p=urcu.git

diff --git a/rculfhash.c b/rculfhash.c
index 1487980..cd25d33 100644
--- a/rculfhash.c
+++ b/rculfhash.c
@@ -246,7 +246,7 @@ struct cds_lfht {
 	void (*cds_lfht_rcu_register_thread)(void);
 	void (*cds_lfht_rcu_unregister_thread)(void);
 	pthread_attr_t *resize_attr;	/* Resize threads attributes */
-	unsigned long count;		/* global approximate item count */
+	long count;			/* global approximate item count */
 	struct ht_items_count *percpu_count;	/* per-cpu item count */
 };
 
@@ -556,7 +556,7 @@ void ht_count_add(struct cds_lfht *ht, unsigned long size)
 		return;
 	percpu_count = uatomic_add_return(&ht->percpu_count[cpu].add, 1);
 	if (unlikely(!(percpu_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) {
-		unsigned long count;
+		long count;
 
 		dbg_printf("add percpu %lu\n", percpu_count);
 		count = uatomic_add_return(&ht->count,
@@ -565,7 +565,7 @@ void ht_count_add(struct cds_lfht *ht, unsigned long size)
 		if (!(count & (count - 1))) {
 			if ((count >> CHAIN_LEN_RESIZE_THRESHOLD) < size)
 				return;
-			dbg_printf("add set global %lu\n", count);
+			dbg_printf("add set global %ld\n", count);
 			cds_lfht_resize_lazy_count(ht, size,
 				count >> (CHAIN_LEN_TARGET - 1));
 		}
@@ -583,9 +583,9 @@ void ht_count_del(struct cds_lfht *ht, unsigned long size)
 	cpu = ht_get_cpu();
 	if (unlikely(cpu < 0))
 		return;
-	percpu_count = uatomic_add_return(&ht->percpu_count[cpu].del, -1);
+	percpu_count = uatomic_add_return(&ht->percpu_count[cpu].del, 1);
 	if (unlikely(!(percpu_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) {
-		unsigned long count;
+		long count;
 
 		dbg_printf("del percpu %lu\n", percpu_count);
 		count = uatomic_add_return(&ht->count,
@@ -594,7 +594,13 @@ void ht_count_del(struct cds_lfht *ht, unsigned long size)
 		if (!(count & (count - 1))) {
 			if ((count >> CHAIN_LEN_RESIZE_THRESHOLD) >= size)
 				return;
-			dbg_printf("del set global %lu\n", count);
+			dbg_printf("del set global %ld\n", count);
+			/*
+			 * Don't shrink table if the number of nodes is below a
+			 * certain threshold.
+			 */
+			if (count < (1UL << COUNT_COMMIT_ORDER) * (nr_cpus_mask + 1))
+				return;
 			cds_lfht_resize_lazy_count(ht, size,
 				count >> (CHAIN_LEN_TARGET - 1));
 		}
@@ -1446,13 +1452,25 @@ int cds_lfht_destroy(struct cds_lfht *ht, pthread_attr_t **attr)
 }
 
 void cds_lfht_count_nodes(struct cds_lfht *ht,
+		long *approx_before,
 		unsigned long *count,
-		unsigned long *removed)
+		unsigned long *removed,
+		long *approx_after)
 {
 	struct cds_lfht_node *node, *next;
 	struct _cds_lfht_node *lookup;
 	unsigned long nr_dummy = 0;
 
+	*approx_before = 0;
+	if (nr_cpus_mask >= 0) {
+		int i;
+
+		for (i = 0; i < nr_cpus_mask + 1; i++) {
+			*approx_before += uatomic_read(&ht->percpu_count[i].add);
+			*approx_before -= uatomic_read(&ht->percpu_count[i].del);
+		}
+	}
+
 	*count = 0;
 	*removed = 0;
 
@@ -1462,8 +1480,10 @@ void cds_lfht_count_nodes(struct cds_lfht *ht,
 	do {
 		next = rcu_dereference(node->p.next);
 		if (is_removed(next)) {
-			assert(!is_dummy(next));
-			(*removed)++;
+			if (!is_dummy(next))
+				(*removed)++;
+			else
+				(nr_dummy)++;
 		} else if (!is_dummy(next))
 			(*count)++;
 		else
@@ -1471,6 +1491,15 @@ void cds_lfht_count_nodes(struct cds_lfht *ht,
 		node = clear_flag(next);
 	} while (!is_end(node));
 	dbg_printf("number of dummy nodes: %lu\n", nr_dummy);
+	*approx_after = 0;
+	if (nr_cpus_mask >= 0) {
+		int i;
+
+		for (i = 0; i < nr_cpus_mask + 1; i++) {
+			*approx_after += uatomic_read(&ht->percpu_count[i].add);
+			*approx_after -= uatomic_read(&ht->percpu_count[i].del);
+		}
+	}
 }
 
 /* called with resize mutex held */