perf report: Don't show blank lines if entry has no callchain

When all callchains of a hist entry is percent-limited, do not add a
blank line at the end.  It makes the entry look like it doesn't have
callchains.

Reported-and-Tested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160128122454.GA27446@danjae.kornet
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/tools/perf/ui/stdio/hist.c b/tools/perf/ui/stdio/hist.c
index 76ff46becac8..691e52ce7510 100644
--- a/tools/perf/ui/stdio/hist.c
+++ b/tools/perf/ui/stdio/hist.c
@@ -233,7 +233,10 @@ static size_t callchain__fprintf_graph(FILE *fp, struct rb_root *root,
 
         ret += __callchain__fprintf_graph(fp, root, total_samples,
                                           1, 1, left_margin);
-        ret += fprintf(fp, "\n");
+        if (ret) {
+                /* do not add a blank line if it printed nothing */
+                ret += fprintf(fp, "\n");
+        }
 
         return ret;
 }