rculfhash: handle small and negative table size approximation

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/rculfhash.c b/rculfhash.c
index 7e959fb4cd8228b161cbb7b4516ff36c4224270b..9a95be260783e66aea715fa3806f0e5f0571e66f 100644 (file)
--- a/rculfhash.c
+++ b/rculfhash.c
@@ -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 +565,13 @@ 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);
+                       /*
+                        * Don't resize table if the number of nodes is below a
+                        * certain threshold.
+                        */
+                       if (count < (1UL << COUNT_COMMIT_ORDER))
+                               return;
                        cds_lfht_resize_lazy_count(ht, size,
                                count >> (CHAIN_LEN_TARGET - 1));
                }
@@ -585,7 +591,7 @@ void ht_count_del(struct cds_lfht *ht, unsigned long size)
                return;
        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 +600,13 @@ 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 resize table if the number of nodes is below a
+                        * certain threshold.
+                        */
+                       if (count < (1UL << COUNT_COMMIT_ORDER))
+                               return;
                        cds_lfht_resize_lazy_count(ht, size,
                                count >> (CHAIN_LEN_TARGET - 1));
                }