/*
* Minimum number of dummy nodes to touch per thread to parallelize grow/shrink.
*/
-#define MIN_PARTITION_PER_THREAD 4096
+#define MIN_PARTITION_PER_THREAD_ORDER 12
+#define MIN_PARTITION_PER_THREAD (1UL << MIN_PARTITION_PER_THREAD_ORDER)
#ifndef min
#define min(a, b) ((a) < (b) ? (a) : (b))
#define END_VALUE NULL
struct ht_items_count {
- unsigned long add, remove;
+ unsigned long add, del;
} __attribute__((aligned(CAA_CACHE_LINE_SIZE)));
struct rcu_level {
}
static
-void ht_count_remove(struct cds_lfht *ht, unsigned long size)
+void ht_count_del(struct cds_lfht *ht, unsigned long size)
{
unsigned long percpu_count;
int cpu;
cpu = ht_get_cpu();
if (unlikely(cpu < 0))
return;
- percpu_count = uatomic_add_return(&ht->percpu_count[cpu].remove, -1);
+ percpu_count = uatomic_add_return(&ht->percpu_count[cpu].del, -1);
if (unlikely(!(percpu_count & ((1UL << COUNT_COMMIT_ORDER) - 1)))) {
unsigned long count;
- dbg_printf("remove percpu %lu\n", percpu_count);
+ dbg_printf("del percpu %lu\n", percpu_count);
count = uatomic_add_return(&ht->count,
-(1UL << COUNT_COMMIT_ORDER));
/* If power of 2 */
if (!(count & (count - 1))) {
if ((count >> CHAIN_LEN_RESIZE_THRESHOLD) >= size)
return;
- dbg_printf("remove set global %lu\n", count);
+ dbg_printf("del set global %lu\n", count);
cds_lfht_resize_lazy_count(ht, size,
count >> (CHAIN_LEN_TARGET - 1));
}
}
static
-void ht_count_remove(struct cds_lfht *ht, unsigned long size)
+void ht_count_del(struct cds_lfht *ht, unsigned long size)
{
}
}
static
-int _cds_lfht_remove(struct cds_lfht *ht, unsigned long size,
+int _cds_lfht_del(struct cds_lfht *ht, unsigned long size,
struct cds_lfht_node *node,
int dummy_removal)
{
{
unsigned long partition_len;
struct partition_resize_work *work;
- int cpu, ret;
+ 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_cpus_mask + 1);
- work = calloc(nr_cpus_mask + 1, sizeof(*work));
- thread_id = calloc(nr_cpus_mask + 1, sizeof(*thread_id));
+ /*
+ * Note: nr_cpus_mask + 1 is always power of 2.
+ * We spawn just the number of threads we need to satisfy the minimum
+ * partition size, up to the number of CPUs in the system.
+ */
+ nr_threads = min(nr_cpus_mask + 1,
+ len >> MIN_PARTITION_PER_THREAD_ORDER);
+ 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 (cpu = 0; cpu < nr_cpus_mask + 1; cpu++) {
- work[cpu].ht = ht;
- work[cpu].i = i;
- work[cpu].len = partition_len;
- work[cpu].start = cpu * partition_len;
- work[cpu].fct = fct;
- ret = pthread_create(&thread_id[cpu], ht->resize_attr,
- partition_resize_thread, &work[cpu]);
+ for (thread = 0; thread < nr_threads; thread++) {
+ work[thread].ht = ht;
+ work[thread].i = i;
+ work[thread].len = partition_len;
+ work[thread].start = thread * partition_len;
+ work[thread].fct = fct;
+ ret = pthread_create(&thread_id[thread], ht->resize_attr,
+ partition_resize_thread, &work[thread]);
assert(!ret);
}
- for (cpu = 0; cpu < nr_cpus_mask + 1; cpu++) {
- ret = pthread_join(thread_id[cpu], NULL);
+ for (thread = 0; thread < nr_threads; thread++) {
+ ret = pthread_join(thread_id[thread], NULL);
assert(!ret);
}
free(work);
unsigned long len)
{
assert(nr_cpus_mask != -1);
- if (nr_cpus_mask < 0 || len < (nr_cpus_mask + 1) * MIN_PARTITION_PER_THREAD) {
+ if (nr_cpus_mask < 0 || len < 2 * MIN_PARTITION_PER_THREAD) {
ht->cds_lfht_rcu_thread_online();
init_table_populate_partition(ht, i, 0, len);
ht->cds_lfht_rcu_thread_offline();
i, j, !i ? 0 : (1UL << (i - 1)) + j);
fini_node->p.reverse_hash =
bit_reverse_ulong(!i ? 0 : (1UL << (i - 1)) + j);
- (void) _cds_lfht_remove(ht, !i ? 0 : (1UL << (i - 1)),
+ (void) _cds_lfht_del(ht, !i ? 0 : (1UL << (i - 1)),
fini_node, 1);
if (CMM_LOAD_SHARED(ht->in_progress_destroy))
break;
{
assert(nr_cpus_mask != -1);
- if (nr_cpus_mask < 0 || len < (nr_cpus_mask + 1) * MIN_PARTITION_PER_THREAD) {
+ if (nr_cpus_mask < 0 || len < 2 * MIN_PARTITION_PER_THREAD) {
ht->cds_lfht_rcu_thread_online();
remove_table_partition(ht, i, 0, len);
ht->cds_lfht_rcu_thread_offline();
return ret;
}
-int cds_lfht_remove(struct cds_lfht *ht, struct cds_lfht_node *node)
+int cds_lfht_del(struct cds_lfht *ht, struct cds_lfht_node *node)
{
unsigned long size;
int ret;
size = rcu_dereference(ht->t.size);
- ret = _cds_lfht_remove(ht, size, node, 0);
+ ret = _cds_lfht_del(ht, size, node, 0);
if (!ret)
- ht_count_remove(ht, size);
+ ht_count_del(ht, size);
return ret;
}