Suricata

Currently, thread locals are used for the packet pool. This would break engine isolation if multiple distinct engines were to be created in the same process space.

Converting the "fast" path to a packet pool stored on the ThreadVars is not hard, however, the optimization for cross-thread returns does make use of thread local to prevent needing to lock on every non-local return, but instead batching then locking to move multiple packets back their thread pool at once