X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=rculfhash.c;h=074a6f4ea8c4c40f7b2f7374d3ecdc8387e34bff;hb=860d07e812c3001e9d6ce261c8b861dabd3203b3;hp=42501a1f030c6ee29fb0c40e5fdc02394da06992;hpb=b7d619b0a4d1613664285e3986b930a05c131c70;p=urcu.git

diff --git a/rculfhash.c b/rculfhash.c
index 42501a1..074a6f4 100644
--- a/rculfhash.c
+++ b/rculfhash.c
@@ -180,7 +180,8 @@
 /*
  * 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))
@@ -203,7 +204,7 @@
 #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 {
@@ -564,7 +565,7 @@ void ht_count_add(struct cds_lfht *ht, unsigned long size)
 }
 
 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;
@@ -574,18 +575,18 @@ void ht_count_remove(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].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));
 		}
@@ -613,7 +614,7 @@ void ht_count_add(struct cds_lfht *ht, unsigned long size)
 }
 
 static
-void ht_count_remove(struct cds_lfht *ht, unsigned long size)
+void ht_count_del(struct cds_lfht *ht, unsigned long size)
 {
 }
 
@@ -843,7 +844,7 @@ gc_end:
 }
 
 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)
 {
@@ -914,26 +915,33 @@ void partition_resize_helper(struct cds_lfht *ht, unsigned long i,
 {
 	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);
@@ -979,7 +987,7 @@ void init_table_populate(struct cds_lfht *ht, unsigned long i,
 			 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();
@@ -1069,7 +1077,7 @@ void remove_table_partition(struct cds_lfht *ht, unsigned long i,
 			   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;
@@ -1082,7 +1090,7 @@ void remove_table(struct cds_lfht *ht, unsigned long i, 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();
 		remove_table_partition(ht, i, 0, len);
 		ht->cds_lfht_rcu_thread_offline();
@@ -1291,15 +1299,15 @@ struct cds_lfht_node *cds_lfht_add_unique(struct cds_lfht *ht,
 	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;
 }