Method allocNextSegment

kernels/subdiv/tessellation_cache.cpp:86–132

   }

  void SharedLazyTessellationCache::allocNextSegment() 
  {
    if (reset_state.try_lock())
    {
      if (next_block >= switch_block_threshold)
      {
        /* lock the linked list of thread states */
        
        linkedlist_mtx.lock();
        
        /* block all threads */
        for (ThreadWorkState *t=current_t_state;t!=nullptr;t=t->next)
          if (lockThread(t,THREAD_BLOCK_ATOMIC_ADD) != 0)
            waitForUsersLessEqual(t,THREAD_BLOCK_ATOMIC_ADD);
        
        /* switch to the next segment */
        addCurrentIndex();
        CACHE_STATS(PRINT("RESET TESS CACHE"));
        
#if FORCE_SIMPLE_FLUSH == 1
        next_block = 0;
        switch_block_threshold = maxBlocks;
#else
        const size_t region = localTime % NUM_CACHE_SEGMENTS;
        next_block = region * (maxBlocks/NUM_CACHE_SEGMENTS);
        switch_block_threshold = next_block + (maxBlocks/NUM_CACHE_SEGMENTS);
        assert( switch_block_threshold <= maxBlocks );
#endif
        
        CACHE_STATS(SharedTessellationCacheStats::cache_flushes++);
        
        /* release all blocked threads */
        
        for (ThreadWorkState *t=current_t_state;t!=nullptr;t=t->next)
          unlockThread(t,-THREAD_BLOCK_ATOMIC_ADD);
        
        /* unlock the linked list of thread states */
        
        linkedlist_mtx.unlock();
	
        
      }
      reset_state.unlock();
    }
    else
      reset_state.wait_until_unlocked();	   
  }
  
  
  void SharedLazyTessellationCache::reset()