add an explanatory comment

diff --git a/src/or/cpuworker.c b/src/or/cpuworker.c
index e3781ada1c264dfa8f45bb179da327bf0fb6ca43..d511ecf84c47f7ed1204d13f57738917c79a5bc7 100644 (file)
--- a/src/or/cpuworker.c
+++ b/src/or/cpuworker.c
@@ -178,8 +178,12 @@ update_state_threadfn(void *state_, void *work_)
 void
 cpuworkers_rotate_keyinfo(void)
 {
-  if (!threadpool)
+  if (!threadpool) {
+    /* If we're a client, then we won't have cpuworkers, and we won't need
+     * to tell them to rotate their state.
+     */
     return;
+  }
   if (threadpool_queue_update(threadpool,
                               worker_state_new,
                               update_state_threadfn,