Why no one use RtlxxxHashTable?

tanda996

1. I find out that ntoskrnl exported run-time hashtable library:
   

but when searching it on google there is no one use or an example about it.
is it have many disadvantage or something?

2. If someone have experienced on RtlxxxHashTable pls review my codes (insert/remove and clear function) with RtlxxxHashTable below, it is implemented right? (because it undocumented).

void
UpdateTable(
    _In_ ULONG ProcessId,
    _In_ bool Insert
)
{
    sync::AutoLock _(m_lock); // RAII fast mutex lock
    if (Insert) // insert
    {
            auto entry = ExAllocatePool(PagedPool, sizeof(MY_STRUCT_ENTRY));
            if (entry)
            {
                RtlInsertEntryHashTable(m_hashTable, &entry->entry, ULONG_PTR(ProcessId), nullptr); // m_hashTable is a class member;
            }
    }
    else // remove
    {
        auto entry = RtlLookupEntryHashTable(m_hashTable, ULONG_PTR(ProcessId), nullptr);
        if (entry)
        {
            RtlRemoveEntryHashTable(m_hashTable, entry, nullptr);
            ExFreePoo(entry);
        }
    }
}


void
Clear(
)
{
    sync::AutoLock _(m_lock); // RAII fast mutex lock
    if (m_hashTable) // a class member;
    {
        RTL_DYNAMIC_HASH_TABLE_ENUMERATOR enumrator = {};
        if (RtlInitEnumerationHashTable(m_hashTable, &enumrator))
        {
            while (true)
            {
                auto entry = RtlEnumerateEntryHashTable(m_hashTable, &enumrator);
                if (entry == nullptr)
                {
                    break;
                }
                RtlRemoveEntryHashTable(m_hashTable, entry, nullptr);
                ExFreePool(entry);
            }
            RtlEndEnumerationHashTable(m_hashTable, &enumrator);
        }
        RtlDeleteHashTable(m_hashTable);
    }
}

Bo_Brantén

There is some examples here: http://scrammed.blogspot.com/2014/11/solution-to-some-of-windows-kernel.html