Please move this into a separate function:

```c
static _Bool drop_metric (void) {
  /* Check the most common condition first. */
  if (write_queue_size <= writequeuelengthlimit_low)
    return 0;
  …
}
```

Then, in `plugin_dispatch_values_internal` do:

```c
if (drop_metric ())
  return (0);
```