systemd.diff

diff --git a/lib/Mojo/Server/Hypnotoad.pm b/lib/Mojo/Server/Hypnotoad.pm
index 3a0af10..f884c3c 100644
--- a/lib/Mojo/Server/Hypnotoad.pm
+++ b/lib/Mojo/Server/Hypnotoad.pm
@@ -72,7 +72,8 @@ sub run {
   $prefork->daemonize if !$ENV{HYPNOTOAD_FOREGROUND} && $ENV{HYPNOTOAD_REV} < 3;
 
   # Start accepting connections
-  local $SIG{USR2} = sub { $self->{upgrade} ||= steady_time };
+  local $SIG{USR2}
+    = sub { $prefork->cleanup(0) and ($self->{upgrade} ||= steady_time) };
   $prefork->cleanup(1)->run;
 }
 
@@ -107,6 +108,8 @@ sub _manage {
     return unless $prefork->healthy == $prefork->workers;
     $log->info("Upgrade successful, stopping $ENV{HYPNOTOAD_PID}");
     kill 'QUIT', $ENV{HYPNOTOAD_PID};
+    unlink $prefork->pid_file;
+    $prefork->ensure_pid_file;
   }
   $ENV{HYPNOTOAD_PID} = $$ unless ($ENV{HYPNOTOAD_PID} // '') eq $$;
 
@@ -121,7 +124,7 @@ sub _manage {
     }
 
     # Timeout
-    kill 'KILL', $self->{new}
+    $prefork->cleanup(1) and kill 'KILL', $self->{new}
       if $self->{upgrade} + $self->upgrade_timeout <= steady_time;
   }
 }