Fix: RCU hash table seed

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

diff --git a/src/common/hashtable/hashtable.c b/src/common/hashtable/hashtable.c
index 187a4d6b3ebabf4c6b6c612bcb8f36835ba3a24b..24d579773e0ab26d89cfb5f078f84562ce4431df 100644 (file)
--- a/src/common/hashtable/hashtable.c
+++ b/src/common/hashtable/hashtable.c
@@ -27,10 +27,10 @@
 #include "hashtable.h"
 #include "utils.h"
 
-#define HASH_SEED            0x42UL            /* The answer to life */
+unsigned long lttng_ht_seed;
 
 static unsigned long min_hash_alloc_size = 1;
-static unsigned long max_hash_buckets_size = (1UL << 20);
+static unsigned long max_hash_buckets_size = 0;
 
 /*
  * Match function for string node.
@@ -72,7 +72,7 @@ struct lttng_ht *lttng_ht_new(unsigned long size, int type)
        }
 
        ht->ht = cds_lfht_new(size, min_hash_alloc_size, max_hash_buckets_size,
-                       CDS_LFHT_AUTO_RESIZE, NULL);
+                       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.
@@ -110,6 +110,7 @@ void lttng_ht_destroy(struct lttng_ht *ht)
 
        ret = cds_lfht_destroy(ht->ht, NULL);
        assert(!ret);
+       free(ht);
 }
 
 /*
@@ -162,7 +163,7 @@ void lttng_ht_lookup(struct lttng_ht *ht, void *key,
        assert(ht);
        assert(ht->ht);
 
-       cds_lfht_lookup(ht->ht, ht->hash_fct(key, HASH_SEED),
+       cds_lfht_lookup(ht->ht, ht->hash_fct(key, lttng_ht_seed),
                        ht->match_fct, key, &iter->iter);
 }
 
@@ -177,11 +178,24 @@ void lttng_ht_add_unique_str(struct lttng_ht *ht,
        assert(ht->ht);
        assert(node);
 
-       node_ptr = cds_lfht_add_unique(ht->ht, ht->hash_fct(node->key, HASH_SEED),
+       node_ptr = cds_lfht_add_unique(ht->ht, ht->hash_fct(node->key, lttng_ht_seed),
                        ht->match_fct, node->key, &node->node);
        assert(node_ptr == &node->node);
 }
 
+/*
+ * Add unsigned long node to hashtable.
+ */
+void lttng_ht_add_ulong(struct lttng_ht *ht, struct lttng_ht_node_ulong *node)
+{
+       assert(ht);
+       assert(ht->ht);
+       assert(node);
+
+       cds_lfht_add(ht->ht, ht->hash_fct((void *) node->key, lttng_ht_seed),
+                       &node->node);
+}
+
 /*
  * Add unique unsigned long node to hashtable.
  */
@@ -194,7 +208,7 @@ void lttng_ht_add_unique_ulong(struct lttng_ht *ht,
        assert(node);
 
        node_ptr = cds_lfht_add_unique(ht->ht,
-                       ht->hash_fct((void *) node->key, HASH_SEED), ht->match_fct,
+                       ht->hash_fct((void *) node->key, lttng_ht_seed), ht->match_fct,
                        (void *) node->key, &node->node);
        assert(node_ptr == &node->node);
 }
@@ -211,7 +225,7 @@ struct lttng_ht_node_ulong *lttng_ht_add_replace_ulong(struct lttng_ht *ht,
        assert(node);
 
        node_ptr = cds_lfht_add_replace(ht->ht,
-                       ht->hash_fct((void *) node->key, HASH_SEED), ht->match_fct,
+                       ht->hash_fct((void *) node->key, lttng_ht_seed), ht->match_fct,
                        (void *) node->key, &node->node);
        if (!node_ptr) {
                return NULL;
@@ -304,3 +318,12 @@ struct lttng_ht_node_ulong *lttng_ht_iter_get_node_ulong(
        }
        return caa_container_of(node, struct lttng_ht_node_ulong, node);
 }
+
+/*
+ * lib constructor
+ */
+static void __attribute__((constructor)) _init()
+{
+       /* Init hash table seed */
+       lttng_ht_seed = (unsigned long) time(NULL);
+}