Fix: hashtable: take split_count_order into account

This makes check_resize() handle split-counters more precisely.

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

diff --git a/src/common/hashtable/rculfhash.c b/src/common/hashtable/rculfhash.c
index ebdc4ffaa8ee84842eb18c4c0588042fade9c66c..0ddd21a3b6335ccf3fb2ddb5ea5f1a9dbba1564c 100644 (file)
--- a/src/common/hashtable/rculfhash.c
+++ b/src/common/hashtable/rculfhash.c
@@ -570,6 +570,7 @@ void cds_lfht_resize_lazy_count(struct cds_lfht *ht, unsigned long size,
 
 static long nr_cpus_mask = -1;
 static long split_count_mask = -1;
+static int split_count_order = -1;
 
 #if defined(HAVE_SYSCONF)
 static void ht_init_nr_cpus_mask(void)
@@ -606,6 +607,8 @@ void alloc_split_items_count(struct cds_lfht *ht)
                        split_count_mask = DEFAULT_SPLIT_COUNT_MASK;
                else
                        split_count_mask = nr_cpus_mask;
+               split_count_order =
+                       cds_lfht_get_count_order_ulong(split_count_mask + 1);
        }
 
        assert(split_count_mask >= 0);
@@ -721,7 +724,7 @@ void check_resize(struct cds_lfht *ht, unsigned long size, uint32_t chain_len)
         * Use bucket-local length for small table expand and for
         * environments lacking per-cpu data support.
         */
-       if (count >= (1UL << COUNT_COMMIT_ORDER))
+       if (count >= (1UL << (COUNT_COMMIT_ORDER + split_count_order)))
                return;
        if (chain_len > 100)
                dbg_printf("WARNING: large chain length: %u.\n",
@@ -735,7 +738,9 @@ void check_resize(struct cds_lfht *ht, unsigned long size, uint32_t chain_len)
                growth = cds_lfht_get_count_order_u32(chain_len
                                - (CHAIN_LEN_TARGET - 1));
                if ((ht->flags & CDS_LFHT_ACCOUNTING)
-                               && (size << growth) >= (1UL << COUNT_COMMIT_ORDER)) {
+                               && (size << growth)
+                                       >= (1UL << (COUNT_COMMIT_ORDER
+                                               + split_count_order))) {
                        /*
                         * If ideal growth expands the hash table size
                         * beyond the "small hash table" sizes, use the
@@ -745,8 +750,8 @@ void check_resize(struct cds_lfht *ht, unsigned long size, uint32_t chain_len)
                         * the chain length is used to expand the hash
                         * table in every case.
                         */
-                       growth = COUNT_COMMIT_ORDER -
-                               cds_lfht_get_count_order_u32(size);
+                       growth = COUNT_COMMIT_ORDER + split_count_order
+                               - cds_lfht_get_count_order_ulong(size);
                        if (growth <= 0)
                                return;
                }