[lttng-tools.git] / src / common / hashtable / hashtable.c

/*
 * Copyright (C) 2011 EfficiOS Inc.
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

#define _LGPL_SOURCE
#include <assert.h>
#include <string.h>
#include <urcu.h>
#include <urcu/compiler.h>

#include <common/common.h>
#include <common/defaults.h>

#include "hashtable.h"
#include "utils.h"

/* seed_lock protects both seed_init and lttng_ht_seed. */
static pthread_mutex_t seed_lock = PTHREAD_MUTEX_INITIALIZER;
static bool seed_init;

static unsigned long min_hash_alloc_size = 1;
static unsigned long max_hash_buckets_size = 0;

/*
 * Getter/lookup functions need to be called with RCU read-side lock
 * held. However, modification functions (add, add_unique, replace, del)
 * take the RCU lock internally, so it does not matter whether the
 * caller hold the RCU lock or not.
 */

/*
 * Match function for string node.
 */
static int match_str(struct cds_lfht_node *node, const void *key)
{
	struct lttng_ht_node_str *match_node =
		caa_container_of(node, struct lttng_ht_node_str, node);

	return hash_match_key_str(match_node->key, (void *) key);
}

/*
 * Match function for ulong node.
 */
static int match_ulong(struct cds_lfht_node *node, const void *key)
{
	struct lttng_ht_node_ulong *match_node =
		caa_container_of(node, struct lttng_ht_node_ulong, node);

	return hash_match_key_ulong((void *) match_node->key, (void *) key);
}

/*
 * Match function for u64 node.
 */
static int match_u64(struct cds_lfht_node *node, const void *key)
{
	struct lttng_ht_node_u64 *match_node =
		caa_container_of(node, struct lttng_ht_node_u64, node);

	return hash_match_key_u64(&match_node->key, (void *) key);
}

/*
 * Match function for two uint64_t node.
 */
static int match_two_u64(struct cds_lfht_node *node, const void *key)
{
	struct lttng_ht_node_two_u64 *match_node =
		caa_container_of(node, struct lttng_ht_node_two_u64, node);

	return hash_match_key_two_u64((void *) &match_node->key, (void *) key);
}

/*
 * Return an allocated lttng hashtable.
 */
LTTNG_HIDDEN
struct lttng_ht *lttng_ht_new(unsigned long size, int type)
{
	struct lttng_ht *ht;

	/* Test size */
	if (!size)
		size = DEFAULT_HT_SIZE;

	pthread_mutex_lock(&seed_lock);
	if (!seed_init) {
		lttng_ht_seed = (unsigned long) time(NULL);
		seed_init = true;
	}
	pthread_mutex_unlock(&seed_lock);

	ht = zmalloc(sizeof(*ht));
	if (ht == NULL) {
		PERROR("zmalloc lttng_ht");
		goto error;
	}

	ht->ht = cds_lfht_new(size, min_hash_alloc_size, max_hash_buckets_size,
			CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING, NULL);
	/*
	 * There is already an assert in the RCU hashtable code so if the ht is
	 * NULL here there is a *huge* problem.
	 */
	assert(ht->ht);

	switch (type) {
	case LTTNG_HT_TYPE_STRING:
		ht->match_fct = match_str;
		ht->hash_fct = hash_key_str;
		break;
	case LTTNG_HT_TYPE_ULONG:
		ht->match_fct = match_ulong;
		ht->hash_fct = hash_key_ulong;
		break;
	case LTTNG_HT_TYPE_U64:
		ht->match_fct = match_u64;
		ht->hash_fct = hash_key_u64;
		break;
	case LTTNG_HT_TYPE_TWO_U64:
		ht->match_fct = match_two_u64;
		ht->hash_fct = hash_key_two_u64;
		break;
	default:
		ERR("Unknown lttng hashtable type %d", type);
		lttng_ht_destroy(ht);
		goto error;
	}

	DBG3("Created hashtable size %lu at %p of type %d", size, ht->ht, type);

	return ht;

error:
	return NULL;
}

/*
 * Free a lttng hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_destroy(struct lttng_ht *ht)
{
	int ret;

	ret = cds_lfht_destroy(ht->ht, NULL);
	assert(!ret);
	free(ht);
}

/*
 * Init lttng ht node string.
 */
LTTNG_HIDDEN
void lttng_ht_node_init_str(struct lttng_ht_node_str *node, char *key)
{
	assert(node);

	node->key = key;
	cds_lfht_node_init(&node->node);
}

/*
 * Init lttng ht node unsigned long.
 */
LTTNG_HIDDEN
void lttng_ht_node_init_ulong(struct lttng_ht_node_ulong *node,
		unsigned long key)
{
	assert(node);

	node->key = key;
	cds_lfht_node_init(&node->node);
}

/*
 * Init lttng ht node uint64_t.
 */
LTTNG_HIDDEN
void lttng_ht_node_init_u64(struct lttng_ht_node_u64 *node,
		uint64_t key)
{
	assert(node);

	node->key = key;
	cds_lfht_node_init(&node->node);
}

/*
 * Init lttng ht node with two uint64_t.
 */
LTTNG_HIDDEN
void lttng_ht_node_init_two_u64(struct lttng_ht_node_two_u64 *node,
		uint64_t key1, uint64_t key2)
{
	assert(node);

	node->key.key1 = key1;
	node->key.key2 = key2;
	cds_lfht_node_init(&node->node);
}

/*
 * Free lttng ht node string.
 */
LTTNG_HIDDEN
void lttng_ht_node_free_str(struct lttng_ht_node_str *node)
{
	assert(node);
	free(node);
}

/*
 * Free lttng ht node unsigned long.
 */
LTTNG_HIDDEN
void lttng_ht_node_free_ulong(struct lttng_ht_node_ulong *node)
{
	assert(node);
	free(node);
}

/*
 * Free lttng ht node uint64_t.
 */
LTTNG_HIDDEN
void lttng_ht_node_free_u64(struct lttng_ht_node_u64 *node)
{
	assert(node);
	free(node);
}

/*
 * Free lttng ht node two uint64_t.
 */
LTTNG_HIDDEN
void lttng_ht_node_free_two_u64(struct lttng_ht_node_two_u64 *node)
{
	assert(node);
	free(node);
}

/*
 * Lookup function in hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_lookup(struct lttng_ht *ht, const void *key,
		struct lttng_ht_iter *iter)
{
	assert(ht);
	assert(ht->ht);

	cds_lfht_lookup(ht->ht, ht->hash_fct(key, lttng_ht_seed),
			ht->match_fct, key, &iter->iter);
}

/*
 * Add unique string node to hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_add_unique_str(struct lttng_ht *ht,
		struct lttng_ht_node_str *node)
{
	struct cds_lfht_node *node_ptr;
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	node_ptr = cds_lfht_add_unique(ht->ht, ht->hash_fct(node->key, lttng_ht_seed),
			ht->match_fct, node->key, &node->node);
	rcu_read_unlock();
	assert(node_ptr == &node->node);
}

/*
 * Add string node to hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_add_str(struct lttng_ht *ht,
		struct lttng_ht_node_str *node)
{
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	cds_lfht_add(ht->ht, ht->hash_fct(node->key, lttng_ht_seed),
			&node->node);
	rcu_read_unlock();
}

/*
 * Add unsigned long node to hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_add_ulong(struct lttng_ht *ht, struct lttng_ht_node_ulong *node)
{
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	cds_lfht_add(ht->ht, ht->hash_fct((void *) node->key, lttng_ht_seed),
			&node->node);
	rcu_read_unlock();
}

/*
 * Add uint64_t node to hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_add_u64(struct lttng_ht *ht, struct lttng_ht_node_u64 *node)
{
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	cds_lfht_add(ht->ht, ht->hash_fct(&node->key, lttng_ht_seed),
			&node->node);
	rcu_read_unlock();
}

/*
 * Add unique unsigned long node to hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_add_unique_ulong(struct lttng_ht *ht,
		struct lttng_ht_node_ulong *node)
{
	struct cds_lfht_node *node_ptr;
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	node_ptr = cds_lfht_add_unique(ht->ht,
			ht->hash_fct((void *) node->key, lttng_ht_seed), ht->match_fct,
			(void *) node->key, &node->node);
	rcu_read_unlock();
	assert(node_ptr == &node->node);
}

/*
 * Add unique uint64_t node to hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_add_unique_u64(struct lttng_ht *ht,
		struct lttng_ht_node_u64 *node)
{
	struct cds_lfht_node *node_ptr;
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	node_ptr = cds_lfht_add_unique(ht->ht,
			ht->hash_fct(&node->key, lttng_ht_seed), ht->match_fct,
			&node->key, &node->node);
	rcu_read_unlock();
	assert(node_ptr == &node->node);
}

/*
 * Add unique two uint64_t node to hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_add_unique_two_u64(struct lttng_ht *ht,
		struct lttng_ht_node_two_u64 *node)
{
	struct cds_lfht_node *node_ptr;
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	node_ptr = cds_lfht_add_unique(ht->ht,
			ht->hash_fct((void *) &node->key, lttng_ht_seed), ht->match_fct,
			(void *) &node->key, &node->node);
	rcu_read_unlock();
	assert(node_ptr == &node->node);
}

/*
 * Add replace unsigned long node to hashtable.
 */
LTTNG_HIDDEN
struct lttng_ht_node_ulong *lttng_ht_add_replace_ulong(struct lttng_ht *ht,
		struct lttng_ht_node_ulong *node)
{
	struct cds_lfht_node *node_ptr;
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	node_ptr = cds_lfht_add_replace(ht->ht,
			ht->hash_fct((void *) node->key, lttng_ht_seed), ht->match_fct,
			(void *) node->key, &node->node);
	rcu_read_unlock();
	if (!node_ptr) {
		return NULL;
	} else {
		return caa_container_of(node_ptr, struct lttng_ht_node_ulong, node);
	}
	assert(node_ptr == &node->node);
}

/*
 * Add replace unsigned long node to hashtable.
 */
LTTNG_HIDDEN
struct lttng_ht_node_u64 *lttng_ht_add_replace_u64(struct lttng_ht *ht,
		struct lttng_ht_node_u64 *node)
{
	struct cds_lfht_node *node_ptr;
	assert(ht);
	assert(ht->ht);
	assert(node);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	node_ptr = cds_lfht_add_replace(ht->ht,
			ht->hash_fct(&node->key, lttng_ht_seed), ht->match_fct,
			&node->key, &node->node);
	rcu_read_unlock();
	if (!node_ptr) {
		return NULL;
	} else {
		return caa_container_of(node_ptr, struct lttng_ht_node_u64, node);
	}
	assert(node_ptr == &node->node);
}

/*
 * Delete node from hashtable.
 */
LTTNG_HIDDEN
int lttng_ht_del(struct lttng_ht *ht, struct lttng_ht_iter *iter)
{
	int ret;

	assert(ht);
	assert(ht->ht);
	assert(iter);

	/* RCU read lock protects from ABA. */
	rcu_read_lock();
	ret = cds_lfht_del(ht->ht, iter->iter.node);
	rcu_read_unlock();
	return ret;
}

/*
 * Get first node in the hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_get_first(struct lttng_ht *ht, struct lttng_ht_iter *iter)
{
	assert(ht);
	assert(ht->ht);
	assert(iter);

	cds_lfht_first(ht->ht, &iter->iter);
}

/*
 * Get next node in the hashtable.
 */
LTTNG_HIDDEN
void lttng_ht_get_next(struct lttng_ht *ht, struct lttng_ht_iter *iter)
{
	assert(ht);
	assert(ht->ht);
	assert(iter);

	cds_lfht_next(ht->ht, &iter->iter);
}

/*
 * Return the number of nodes in the hashtable.
 */
LTTNG_HIDDEN
unsigned long lttng_ht_get_count(struct lttng_ht *ht)
{
	long scb, sca;
	unsigned long count;

	assert(ht);
	assert(ht->ht);

	/* RCU read lock protects from ABA and allows RCU traversal. */
	rcu_read_lock();
	cds_lfht_count_nodes(ht->ht, &scb, &count, &sca);
	rcu_read_unlock();

	return count;
}

/*
 * Return lttng ht string node from iterator.
 */
LTTNG_HIDDEN
struct lttng_ht_node_str *lttng_ht_iter_get_node_str(
		struct lttng_ht_iter *iter)
{
	struct cds_lfht_node *node;

	assert(iter);
	node = cds_lfht_iter_get_node(&iter->iter);
	if (!node) {
		return NULL;
	}
	return caa_container_of(node, struct lttng_ht_node_str, node);
}

/*
 * Return lttng ht unsigned long node from iterator.
 */
LTTNG_HIDDEN
struct lttng_ht_node_ulong *lttng_ht_iter_get_node_ulong(
		struct lttng_ht_iter *iter)
{
	struct cds_lfht_node *node;

	assert(iter);
	node = cds_lfht_iter_get_node(&iter->iter);
	if (!node) {
		return NULL;
	}
	return caa_container_of(node, struct lttng_ht_node_ulong, node);
}

/*
 * Return lttng ht unsigned long node from iterator.
 */
LTTNG_HIDDEN
struct lttng_ht_node_u64 *lttng_ht_iter_get_node_u64(
		struct lttng_ht_iter *iter)
{
	struct cds_lfht_node *node;

	assert(iter);
	node = cds_lfht_iter_get_node(&iter->iter);
	if (!node) {
		return NULL;
	}
	return caa_container_of(node, struct lttng_ht_node_u64, node);
}

/*
 * Return lttng ht stream and index id node from iterator.
 */
LTTNG_HIDDEN
struct lttng_ht_node_two_u64 *lttng_ht_iter_get_node_two_u64(
		struct lttng_ht_iter *iter)
{
	struct cds_lfht_node *node;

	assert(iter);
	node = cds_lfht_iter_get_node(&iter->iter);
	if (!node) {
		return NULL;
	}
	return caa_container_of(node, struct lttng_ht_node_two_u64, node);
}
Commit	Line	Data
	1	/*
	2	* Copyright (C) 2011 EfficiOS Inc.
	3	*
	4	* SPDX-License-Identifier: GPL-2.0-only
	5	*
	6	*/
	7
	8	#define _LGPL_SOURCE
	9	#include <assert.h>
	10	#include <string.h>
	11	#include <urcu.h>
	12	#include <urcu/compiler.h>
	13
	14	#include <common/common.h>
	15	#include <common/defaults.h>
	16
	17	#include "hashtable.h"
	18	#include "utils.h"
	19
	20	/* seed_lock protects both seed_init and lttng_ht_seed. */
	21	static pthread_mutex_t seed_lock = PTHREAD_MUTEX_INITIALIZER;
	22	static bool seed_init;
	23
	24	static unsigned long min_hash_alloc_size = 1;
	25	static unsigned long max_hash_buckets_size = 0;
	26
	27	/*
	28	* Getter/lookup functions need to be called with RCU read-side lock
	29	* held. However, modification functions (add, add_unique, replace, del)
	30	* take the RCU lock internally, so it does not matter whether the
	31	* caller hold the RCU lock or not.
	32	*/
	33
	34	/*
	35	* Match function for string node.
	36	*/
	37	static int match_str(struct cds_lfht_node node, const void key)
	38	{
	39	struct lttng_ht_node_str *match_node =
	40	caa_container_of(node, struct lttng_ht_node_str, node);
	41
	42	return hash_match_key_str(match_node->key, (void *) key);
	43	}
	44
	45	/*
	46	* Match function for ulong node.
	47	*/
	48	static int match_ulong(struct cds_lfht_node node, const void key)
	49	{
	50	struct lttng_ht_node_ulong *match_node =
	51	caa_container_of(node, struct lttng_ht_node_ulong, node);
	52
	53	return hash_match_key_ulong((void ) match_node->key, (void ) key);
	54	}
	55
	56	/*
	57	* Match function for u64 node.
	58	*/
	59	static int match_u64(struct cds_lfht_node node, const void key)
	60	{
	61	struct lttng_ht_node_u64 *match_node =
	62	caa_container_of(node, struct lttng_ht_node_u64, node);
	63
	64	return hash_match_key_u64(&match_node->key, (void *) key);
	65	}
	66
	67	/*
	68	* Match function for two uint64_t node.
	69	*/
	70	static int match_two_u64(struct cds_lfht_node node, const void key)
	71	{
	72	struct lttng_ht_node_two_u64 *match_node =
	73	caa_container_of(node, struct lttng_ht_node_two_u64, node);
	74
	75	return hash_match_key_two_u64((void ) &match_node->key, (void ) key);
	76	}
	77
	78	/*
	79	* Return an allocated lttng hashtable.
	80	*/
	81	LTTNG_HIDDEN
	82	struct lttng_ht *lttng_ht_new(unsigned long size, int type)
	83	{
	84	struct lttng_ht *ht;
	85
	86	/* Test size */
	87	if (!size)
	88	size = DEFAULT_HT_SIZE;
	89
	90	pthread_mutex_lock(&seed_lock);
	91	if (!seed_init) {
	92	lttng_ht_seed = (unsigned long) time(NULL);
	93	seed_init = true;
	94	}
	95	pthread_mutex_unlock(&seed_lock);
	96
	97	ht = zmalloc(sizeof(*ht));
	98	if (ht == NULL) {
	99	PERROR("zmalloc lttng_ht");
	100	goto error;
	101	}
	102
	103	ht->ht = cds_lfht_new(size, min_hash_alloc_size, max_hash_buckets_size,
	104	CDS_LFHT_AUTO_RESIZE \| CDS_LFHT_ACCOUNTING, NULL);
	105	/*
	106	* There is already an assert in the RCU hashtable code so if the ht is
	107	* NULL here there is a huge problem.
	108	*/
	109	assert(ht->ht);
	110
	111	switch (type) {
	112	case LTTNG_HT_TYPE_STRING:
	113	ht->match_fct = match_str;
	114	ht->hash_fct = hash_key_str;
	115	break;
	116	case LTTNG_HT_TYPE_ULONG:
	117	ht->match_fct = match_ulong;
	118	ht->hash_fct = hash_key_ulong;
	119	break;
	120	case LTTNG_HT_TYPE_U64:
	121	ht->match_fct = match_u64;
	122	ht->hash_fct = hash_key_u64;
	123	break;
	124	case LTTNG_HT_TYPE_TWO_U64:
	125	ht->match_fct = match_two_u64;
	126	ht->hash_fct = hash_key_two_u64;
	127	break;
	128	default:
	129	ERR("Unknown lttng hashtable type %d", type);
	130	lttng_ht_destroy(ht);
	131	goto error;
	132	}
	133
	134	DBG3("Created hashtable size %lu at %p of type %d", size, ht->ht, type);
	135
	136	return ht;
	137
	138	error:
	139	return NULL;
	140	}
	141
	142	/*
	143	* Free a lttng hashtable.
	144	*/
	145	LTTNG_HIDDEN
	146	void lttng_ht_destroy(struct lttng_ht *ht)
	147	{
	148	int ret;
	149
	150	ret = cds_lfht_destroy(ht->ht, NULL);
	151	assert(!ret);
	152	free(ht);
	153	}
	154
	155	/*
	156	* Init lttng ht node string.
	157	*/
	158	LTTNG_HIDDEN
	159	void lttng_ht_node_init_str(struct lttng_ht_node_str node, char key)
	160	{
	161	assert(node);
	162
	163	node->key = key;
	164	cds_lfht_node_init(&node->node);
	165	}
	166
	167	/*
	168	* Init lttng ht node unsigned long.
	169	*/
	170	LTTNG_HIDDEN
	171	void lttng_ht_node_init_ulong(struct lttng_ht_node_ulong *node,
	172	unsigned long key)
	173	{
	174	assert(node);
	175
	176	node->key = key;
	177	cds_lfht_node_init(&node->node);
	178	}
	179
	180	/*
	181	* Init lttng ht node uint64_t.
	182	*/
	183	LTTNG_HIDDEN
	184	void lttng_ht_node_init_u64(struct lttng_ht_node_u64 *node,
	185	uint64_t key)
	186	{
	187	assert(node);
	188
	189	node->key = key;
	190	cds_lfht_node_init(&node->node);
	191	}
	192
	193	/*
	194	* Init lttng ht node with two uint64_t.
	195	*/
	196	LTTNG_HIDDEN
	197	void lttng_ht_node_init_two_u64(struct lttng_ht_node_two_u64 *node,
	198	uint64_t key1, uint64_t key2)
	199	{
	200	assert(node);
	201
	202	node->key.key1 = key1;
	203	node->key.key2 = key2;
	204	cds_lfht_node_init(&node->node);
	205	}
	206
	207	/*
	208	* Free lttng ht node string.
	209	*/
	210	LTTNG_HIDDEN
	211	void lttng_ht_node_free_str(struct lttng_ht_node_str *node)
	212	{
	213	assert(node);
	214	free(node);
	215	}
	216
	217	/*
	218	* Free lttng ht node unsigned long.
	219	*/
	220	LTTNG_HIDDEN
	221	void lttng_ht_node_free_ulong(struct lttng_ht_node_ulong *node)
	222	{
	223	assert(node);
	224	free(node);
	225	}
	226
	227	/*
	228	* Free lttng ht node uint64_t.
	229	*/
	230	LTTNG_HIDDEN
	231	void lttng_ht_node_free_u64(struct lttng_ht_node_u64 *node)
	232	{
	233	assert(node);
	234	free(node);
	235	}
	236
	237	/*
	238	* Free lttng ht node two uint64_t.
	239	*/
	240	LTTNG_HIDDEN
	241	void lttng_ht_node_free_two_u64(struct lttng_ht_node_two_u64 *node)
	242	{
	243	assert(node);
	244	free(node);
	245	}
	246
	247	/*
	248	* Lookup function in hashtable.
	249	*/
	250	LTTNG_HIDDEN
	251	void lttng_ht_lookup(struct lttng_ht ht, const void key,
	252	struct lttng_ht_iter *iter)
	253	{
	254	assert(ht);
	255	assert(ht->ht);
	256
	257	cds_lfht_lookup(ht->ht, ht->hash_fct(key, lttng_ht_seed),
	258	ht->match_fct, key, &iter->iter);
	259	}
	260
	261	/*
	262	* Add unique string node to hashtable.
	263	*/
	264	LTTNG_HIDDEN
	265	void lttng_ht_add_unique_str(struct lttng_ht *ht,
	266	struct lttng_ht_node_str *node)
	267	{
	268	struct cds_lfht_node *node_ptr;
	269	assert(ht);
	270	assert(ht->ht);
	271	assert(node);
	272
	273	/* RCU read lock protects from ABA. */
	274	rcu_read_lock();
	275	node_ptr = cds_lfht_add_unique(ht->ht, ht->hash_fct(node->key, lttng_ht_seed),
	276	ht->match_fct, node->key, &node->node);
	277	rcu_read_unlock();
	278	assert(node_ptr == &node->node);
	279	}
	280
	281	/*
	282	* Add string node to hashtable.
	283	*/
	284	LTTNG_HIDDEN
	285	void lttng_ht_add_str(struct lttng_ht *ht,
	286	struct lttng_ht_node_str *node)
	287	{
	288	assert(ht);
	289	assert(ht->ht);
	290	assert(node);
	291
	292	/* RCU read lock protects from ABA. */
	293	rcu_read_lock();
	294	cds_lfht_add(ht->ht, ht->hash_fct(node->key, lttng_ht_seed),
	295	&node->node);
	296	rcu_read_unlock();
	297	}
	298
	299	/*
	300	* Add unsigned long node to hashtable.
	301	*/
	302	LTTNG_HIDDEN
	303	void lttng_ht_add_ulong(struct lttng_ht ht, struct lttng_ht_node_ulong node)
	304	{
	305	assert(ht);
	306	assert(ht->ht);
	307	assert(node);
	308
	309	/* RCU read lock protects from ABA. */
	310	rcu_read_lock();
	311	cds_lfht_add(ht->ht, ht->hash_fct((void *) node->key, lttng_ht_seed),
	312	&node->node);
	313	rcu_read_unlock();
	314	}
	315
	316	/*
	317	* Add uint64_t node to hashtable.
	318	*/
	319	LTTNG_HIDDEN
	320	void lttng_ht_add_u64(struct lttng_ht ht, struct lttng_ht_node_u64 node)
	321	{
	322	assert(ht);
	323	assert(ht->ht);
	324	assert(node);
	325
	326	/* RCU read lock protects from ABA. */
	327	rcu_read_lock();
	328	cds_lfht_add(ht->ht, ht->hash_fct(&node->key, lttng_ht_seed),
	329	&node->node);
	330	rcu_read_unlock();
	331	}
	332
	333	/*
	334	* Add unique unsigned long node to hashtable.
	335	*/
	336	LTTNG_HIDDEN
	337	void lttng_ht_add_unique_ulong(struct lttng_ht *ht,
	338	struct lttng_ht_node_ulong *node)
	339	{
	340	struct cds_lfht_node *node_ptr;
	341	assert(ht);
	342	assert(ht->ht);
	343	assert(node);
	344
	345	/* RCU read lock protects from ABA. */
	346	rcu_read_lock();
	347	node_ptr = cds_lfht_add_unique(ht->ht,
	348	ht->hash_fct((void *) node->key, lttng_ht_seed), ht->match_fct,
	349	(void *) node->key, &node->node);
	350	rcu_read_unlock();
	351	assert(node_ptr == &node->node);
	352	}
	353
	354	/*
	355	* Add unique uint64_t node to hashtable.
	356	*/
	357	LTTNG_HIDDEN
	358	void lttng_ht_add_unique_u64(struct lttng_ht *ht,
	359	struct lttng_ht_node_u64 *node)
	360	{
	361	struct cds_lfht_node *node_ptr;
	362	assert(ht);
	363	assert(ht->ht);
	364	assert(node);
	365
	366	/* RCU read lock protects from ABA. */
	367	rcu_read_lock();
	368	node_ptr = cds_lfht_add_unique(ht->ht,
	369	ht->hash_fct(&node->key, lttng_ht_seed), ht->match_fct,
	370	&node->key, &node->node);
	371	rcu_read_unlock();
	372	assert(node_ptr == &node->node);
	373	}
	374
	375	/*
	376	* Add unique two uint64_t node to hashtable.
	377	*/
	378	LTTNG_HIDDEN
	379	void lttng_ht_add_unique_two_u64(struct lttng_ht *ht,
	380	struct lttng_ht_node_two_u64 *node)
	381	{
	382	struct cds_lfht_node *node_ptr;
	383	assert(ht);
	384	assert(ht->ht);
	385	assert(node);
	386
	387	/* RCU read lock protects from ABA. */
	388	rcu_read_lock();
	389	node_ptr = cds_lfht_add_unique(ht->ht,
	390	ht->hash_fct((void *) &node->key, lttng_ht_seed), ht->match_fct,
	391	(void *) &node->key, &node->node);
	392	rcu_read_unlock();
	393	assert(node_ptr == &node->node);
	394	}
	395
	396	/*
	397	* Add replace unsigned long node to hashtable.
	398	*/
	399	LTTNG_HIDDEN
	400	struct lttng_ht_node_ulong lttng_ht_add_replace_ulong(struct lttng_ht ht,
	401	struct lttng_ht_node_ulong *node)
	402	{
	403	struct cds_lfht_node *node_ptr;
	404	assert(ht);
	405	assert(ht->ht);
	406	assert(node);
	407
	408	/* RCU read lock protects from ABA. */
	409	rcu_read_lock();
	410	node_ptr = cds_lfht_add_replace(ht->ht,
	411	ht->hash_fct((void *) node->key, lttng_ht_seed), ht->match_fct,
	412	(void *) node->key, &node->node);
	413	rcu_read_unlock();
	414	if (!node_ptr) {
	415	return NULL;
	416	} else {
	417	return caa_container_of(node_ptr, struct lttng_ht_node_ulong, node);
	418	}
	419	assert(node_ptr == &node->node);
	420	}
	421
	422	/*
	423	* Add replace unsigned long node to hashtable.
	424	*/
	425	LTTNG_HIDDEN
	426	struct lttng_ht_node_u64 lttng_ht_add_replace_u64(struct lttng_ht ht,
	427	struct lttng_ht_node_u64 *node)
	428	{
	429	struct cds_lfht_node *node_ptr;
	430	assert(ht);
	431	assert(ht->ht);
	432	assert(node);
	433
	434	/* RCU read lock protects from ABA. */
	435	rcu_read_lock();
	436	node_ptr = cds_lfht_add_replace(ht->ht,
	437	ht->hash_fct(&node->key, lttng_ht_seed), ht->match_fct,
	438	&node->key, &node->node);
	439	rcu_read_unlock();
	440	if (!node_ptr) {
	441	return NULL;
	442	} else {
	443	return caa_container_of(node_ptr, struct lttng_ht_node_u64, node);
	444	}
	445	assert(node_ptr == &node->node);
	446	}
	447
	448	/*
	449	* Delete node from hashtable.
	450	*/
	451	LTTNG_HIDDEN
	452	int lttng_ht_del(struct lttng_ht ht, struct lttng_ht_iter iter)
	453	{
	454	int ret;
	455
	456	assert(ht);
	457	assert(ht->ht);
	458	assert(iter);
	459
	460	/* RCU read lock protects from ABA. */
	461	rcu_read_lock();
	462	ret = cds_lfht_del(ht->ht, iter->iter.node);
	463	rcu_read_unlock();
	464	return ret;
	465	}
	466
	467	/*
	468	* Get first node in the hashtable.
	469	*/
	470	LTTNG_HIDDEN
	471	void lttng_ht_get_first(struct lttng_ht ht, struct lttng_ht_iter iter)
	472	{
	473	assert(ht);
	474	assert(ht->ht);
	475	assert(iter);
	476
	477	cds_lfht_first(ht->ht, &iter->iter);
	478	}
	479
	480	/*
	481	* Get next node in the hashtable.
	482	*/
	483	LTTNG_HIDDEN
	484	void lttng_ht_get_next(struct lttng_ht ht, struct lttng_ht_iter iter)
	485	{
	486	assert(ht);
	487	assert(ht->ht);
	488	assert(iter);
	489
	490	cds_lfht_next(ht->ht, &iter->iter);
	491	}
	492
	493	/*
	494	* Return the number of nodes in the hashtable.
	495	*/
	496	LTTNG_HIDDEN
	497	unsigned long lttng_ht_get_count(struct lttng_ht *ht)
	498	{
	499	long scb, sca;
	500	unsigned long count;
	501
	502	assert(ht);
	503	assert(ht->ht);
	504
	505	/* RCU read lock protects from ABA and allows RCU traversal. */
	506	rcu_read_lock();
	507	cds_lfht_count_nodes(ht->ht, &scb, &count, &sca);
	508	rcu_read_unlock();
	509
	510	return count;
	511	}
	512
	513	/*
	514	* Return lttng ht string node from iterator.
	515	*/
	516	LTTNG_HIDDEN
	517	struct lttng_ht_node_str *lttng_ht_iter_get_node_str(
	518	struct lttng_ht_iter *iter)
	519	{
	520	struct cds_lfht_node *node;
	521
	522	assert(iter);
	523	node = cds_lfht_iter_get_node(&iter->iter);
	524	if (!node) {
	525	return NULL;
	526	}
	527	return caa_container_of(node, struct lttng_ht_node_str, node);
	528	}
	529
	530	/*
	531	* Return lttng ht unsigned long node from iterator.
	532	*/
	533	LTTNG_HIDDEN
	534	struct lttng_ht_node_ulong *lttng_ht_iter_get_node_ulong(
	535	struct lttng_ht_iter *iter)
	536	{
	537	struct cds_lfht_node *node;
	538
	539	assert(iter);
	540	node = cds_lfht_iter_get_node(&iter->iter);
	541	if (!node) {
	542	return NULL;
	543	}
	544	return caa_container_of(node, struct lttng_ht_node_ulong, node);
	545	}
	546
	547	/*
	548	* Return lttng ht unsigned long node from iterator.
	549	*/
	550	LTTNG_HIDDEN
	551	struct lttng_ht_node_u64 *lttng_ht_iter_get_node_u64(
	552	struct lttng_ht_iter *iter)
	553	{
	554	struct cds_lfht_node *node;
	555
	556	assert(iter);
	557	node = cds_lfht_iter_get_node(&iter->iter);
	558	if (!node) {
	559	return NULL;
	560	}
	561	return caa_container_of(node, struct lttng_ht_node_u64, node);
	562	}
	563
	564	/*
	565	* Return lttng ht stream and index id node from iterator.
	566	*/
	567	LTTNG_HIDDEN
	568	struct lttng_ht_node_two_u64 *lttng_ht_iter_get_node_two_u64(
	569	struct lttng_ht_iter *iter)
	570	{
	571	struct cds_lfht_node *node;
	572
	573	assert(iter);
	574	node = cds_lfht_iter_get_node(&iter->iter);
	575	if (!node) {
	576	return NULL;
	577	}
	578	return caa_container_of(node, struct lttng_ht_node_two_u64, node);
	579	}