* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
-#define _GNU_SOURCE
#define _LGPL_SOURCE
#include <assert.h>
#include <string.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;
unsigned long lttng_ht_seed;
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.
*/
/*
* Return an allocated lttng hashtable.
*/
+LTTNG_HIDDEN
struct lttng_ht *lttng_ht_new(unsigned long size, int type)
{
struct lttng_ht *ht;
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");
/*
* Free a lttng hashtable.
*/
+LTTNG_HIDDEN
void lttng_ht_destroy(struct lttng_ht *ht)
{
int ret;
/*
* Init lttng ht node string.
*/
+LTTNG_HIDDEN
void lttng_ht_node_init_str(struct lttng_ht_node_str *node, char *key)
{
assert(node);
/*
* Init lttng ht node unsigned long.
*/
+LTTNG_HIDDEN
void lttng_ht_node_init_ulong(struct lttng_ht_node_ulong *node,
unsigned long key)
{
/*
* Init lttng ht node uint64_t.
*/
+LTTNG_HIDDEN
void lttng_ht_node_init_u64(struct lttng_ht_node_u64 *node,
uint64_t key)
{
/*
* 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)
{
/*
* Free lttng ht node string.
*/
+LTTNG_HIDDEN
void lttng_ht_node_free_str(struct lttng_ht_node_str *node)
{
assert(node);
/*
* Free lttng ht node unsigned long.
*/
+LTTNG_HIDDEN
void lttng_ht_node_free_ulong(struct lttng_ht_node_ulong *node)
{
assert(node);
/*
* Free lttng ht node uint64_t.
*/
+LTTNG_HIDDEN
void lttng_ht_node_free_u64(struct lttng_ht_node_u64 *node)
{
assert(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);
/*
* Lookup function in hashtable.
*/
+LTTNG_HIDDEN
void lttng_ht_lookup(struct lttng_ht *ht, void *key,
struct lttng_ht_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)
{
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->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)
{
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)
{
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)
{
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)
{
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 {
/*
* 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)
{
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 {
/*
* 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);
- return cds_lfht_del(ht->ht, iter->iter.node);
+ /* 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);
/*
* Get next node in the hashtable.
*/
+LTTNG_HIDDEN
void lttng_ht_get_next(struct lttng_ht *ht, struct lttng_ht_iter *iter)
{
assert(ht);
/*
* Return the number of nodes in the hashtable.
*/
+LTTNG_HIDDEN
unsigned long lttng_ht_get_count(struct lttng_ht *ht)
{
long scb, sca;
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)
{
/*
* 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)
{
/*
* 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)
{
/*
* 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)
{
}
return caa_container_of(node, struct lttng_ht_node_two_u64, node);
}
-
-/*
- * lib constructor
- */
-static void __attribute__((constructor)) _init(void)
-{
- /* Init hash table seed */
- lttng_ht_seed = (unsigned long) time(NULL);
-}
projects / lttng-tools.git / blobdiff