perf daemon: Return from kill functions

We should return correctly and warn in both daemon_session__kill() and
daemon__kill() after we tried everything to kill sessions.  The current
code will keep on looping and waiting.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210320221013.1619613-2-jolsa@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-daemon.c

@@ -908,7 +908,9 @@ static void daemon_session__kill(struct daemon_session *session,
 			daemon_session__signal(session, SIGKILL);
 			break;
 		default:
-			break;
+			pr_err("failed to wait for session %s\n",
+			       session->name);
+			return;
 		}
 		how++;
 
@@ -961,7 +963,8 @@ static void daemon__kill(struct daemon *daemon)
 			daemon__signal(daemon, SIGKILL);
 			break;
 		default:
-			break;
+			pr_err("failed to wait for sessions\n");
+			return;
 		}
 		how++;