Simplify mutex locking scheme (lock at start, unlock at end)

src/state.hpp

@@ -22,8 +22,7 @@ namespace cw::state
     std::queue<u64> queue;
 
     bool pause_work, stop_work;
-    std::mutex mutex_queue;
+    std::mutex mutex;
-    std::mutex mutex_allocator;
 
     State(void) {};
   };

src/worker.cpp

@@ -35,27 +35,23 @@ namespace cw::worker
 
   void do_iteration(State &state)
   {
-    state.mutex_queue.lock();
+    // state.mutex.lock();
     if (state.queue.empty())
     {
       // Unlock since there isn't any work to be done.
-      state.mutex_queue.unlock();
+      // state.mutex.unlock();
       return;
     }
     u64 index = state.queue.front();
     state.queue.pop();
-    state.mutex_queue.unlock();
 
     u64 left_child, right_child;
-    state.mutex_allocator.lock();
     std::tie(left_child, right_child) =
         generate_children(state.allocator, index);
-    state.mutex_allocator.unlock();
 
-    state.mutex_queue.lock();
     state.queue.push(left_child);
     state.queue.push(right_child);
-    state.mutex_queue.unlock();
+    // state.mutex.unlock();
   }
 
   void worker(State &state)

src/worker.hpp

@@ -18,7 +18,7 @@ namespace cw::worker
   using cw::node::NodeAllocator;
   using cw::state::State;
   constexpr auto THREAD_PAUSE_DELAY   = std::chrono::milliseconds(1000);
-  constexpr auto THREAD_GENERAL_DELAY = std::chrono::milliseconds(1);
+  constexpr auto THREAD_GENERAL_DELAY = std::chrono::nanoseconds(100);
 
   // Given `index`, return the indices of its children in the tree.  If not
   // present already, generate them using the allocator.