/**Frees allocated TagNode.
*
* @param hash - pointer to SFXHASH that should point to either ssn_tag_cache_ptr
* or host_tag_cache_ptr.
* @param node - pointer to node to be freed
*/
static void TagFree(
SFXHASH *hash,
TagNode *node
)
{
if (node == NULL)
return;
free((void *)node);
tag_memory_usage -= memory_per_node(hash);
}
/** Allocate a TagNode
*
* Alocates a TagNode while guaranteeing that total memory usage remains within TAG_MEMCAP.
* Least used nodes may be deleted from ssn_tag_cache and host_tag_cache to make space if
* the limit is being exceeded.
*
* @param hash - pointer to SFXHASH that should point to either ssn_tag_cache_ptr
* or host_tag_cache_ptr.
*
* @returns a pointer to new TagNode or NULL if memory couldn't * be allocated
*/
static TagNode * TagAlloc(
SFXHASH *hash
)
{
TagNode *tag_node = NULL;
if(tag_memory_usage + memory_per_node(hash) > TAG_MEMCAP)
{
/* aggressively prune */
struct timeval tv;
struct timezone tz;
int pruned_nodes = 0;
tag_alloc_faults++;
gettimeofday(&tv, &tz);
pruned_nodes = PruneTagCache((uint32_t)tv.tv_sec, 0);
if(pruned_nodes == 0)
{
/* if we can't prune due to time, just try to nuke
* 5 not so recently used nodes */
pruned_nodes = PruneTagCache(0, 5);
/* unlikely to happen since memcap has been reached */
if (pruned_nodes == 0)
return NULL;
}
}
tag_node = (TagNode *)calloc(1, sizeof(TagNode));
if (tag_node != NULL)
tag_memory_usage += memory_per_node(hash);
return tag_node;
}
/**Frees allocated TagNode.
*
* @param hash - pointer to SFXHASH that should point to either ssn_tag_cache_ptr
* or host_tag_cache_ptr.
* @param node - pointer to node to be freed
*/
static void TagFree(
SFXHASH *hash,
TagNode *node
)
{
if (node == NULL)
return;
if ( node->metric & TAG_METRIC_SESSION )
s_exclusive = false;
free((void *)node);
tag_memory_usage -= memory_per_node(hash);
}
