packet pool: init pool for autofp workers as well

Introduce a new 'PacketPoolInitEmpty' as these pools will not often
need packets.

Also, don't double 'destroy' in the main thread.

src/suricata.c

@@ -2474,7 +2474,6 @@ int main(int argc, char **argv)
     if (suri.run_mode != RUNMODE_UNIX_SOCKET) {
         DefragDestroy();
     }
-    PacketPoolDestroy();
     MagicDeinit();
     TmqhCleanup();
     TmModuleRunDeInit();

src/tm-threads.c

@@ -402,6 +402,8 @@ void *TmThreadsSlotVar(void *td)
     char run = 1;
     TmEcode r = TM_ECODE_OK;
 
+    PacketPoolInitEmpty();
+
     /* Set the thread name */
     if (SCSetThreadName(tv->name) < 0) {
         SCLogWarning(SC_ERR_THREAD_INIT, "Unable to set thread name");
@@ -524,6 +526,8 @@ void *TmThreadsSlotVar(void *td)
     TmThreadsSetFlag(tv, THV_RUNNING_DONE);
     TmThreadWaitForFlag(tv, THV_DEINIT);
 
+    PacketPoolDestroy();
+
     s = (TmSlot *)tv->tm_slots;
 
     for ( ; s != NULL; s = s->slot_next) {

src/tmqh-packetpool.c

@@ -279,6 +279,19 @@ void PacketPoolReturnPacket(Packet *p)
     }
 }
 
+void PacketPoolInitEmpty(void)
+{
+#ifndef TLS
+    TmqhPacketPoolInit();
+#endif
+
+    PktPool *my_pool = GetThreadPacketPool();
+
+    SCMutexInit(&my_pool->return_stack.mutex, NULL);
+    SCCondInit(&my_pool->return_stack.cond, NULL);
+    SC_ATOMIC_INIT(my_pool->return_stack.sync_now);
+}
+
 void PacketPoolInit(void)
 {
     extern intmax_t max_pending_packets;

src/tmqh-packetpool.h

@@ -71,6 +71,7 @@ Packet *PacketPoolGetPacket(void);
 void PacketPoolWait(void);
 void PacketPoolReturnPacket(Packet *p);
 void PacketPoolInit(void);
+void PacketPoolInitEmpty(void);
 void PacketPoolDestroy(void);
 
 #endif /* __TMQH_PACKETPOOL_H__ */