perf top: Use __fallthrough

The implicit fall through case label here is intended, so let us inform
that to gcc >= 7:

    CC       /tmp/build/perf/builtin-top.o
  builtin-top.c: In function 'display_thread':
  builtin-top.c:644:7: error: this statement may fall through [-Werror=implicit-fallthrough=]
      if (errno == EINTR)
         ^
  builtin-top.c:647:3: note: here
     default:
   ^~~~~~~

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-lmcfnnyx9ic0m6j0aud98p4e@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 20aef9815cd8..d90927f31ff6 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -643,7 +643,7 @@ repeat:
                 case -1:
                         if (errno == EINTR)
                                 continue;
-                        /* Fall trhu */
+                        __fallthrough;
                 default:
                         c = getc(stdin);
                         tcsetattr(0, TCSAFLUSH, &save);