* thread.c (mutex_sleep): [DOC] Awake thread will reacquire lock
  By Tim Abdulla [Fixes GH-342] https://github.com/ruby/ruby/pull/342


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@41977 b2dd03c8-39d4-4d8f-98ff-823fe69b080e