[PATCH 2/2] perf ftrace: Fix display for range of the first bucket

[Namhyung Kim <namhyung@kernel.org>]

When min_latency is not given, it prints 0 - 0.  It should be 0 - 1.

Before:
  $ sudo ./perf ftrace latency -a -T do_futex sleep 1
  #   DURATION     |      COUNT | GRAPH                                          |
       0 -    0 us |        321 | ###########                                    |
  ...

After:
  $ sudo ./perf ftrace latency -a -T do_futex sleep 1
  #   DURATION     |      COUNT | GRAPH                                          |
       0 -    1 us |        699 | ############                                   |
  ...

Fixes: b875b6bf608589 ("perf ftrace latency: Introduce --min-latency to narrow down into a latency range")
Cc: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/builtin-ftrace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/builtin-ftrace.c b/tools/perf/builtin-ftrace.c
index 90cf2c9915a7e35b..cfd770ec72867d77 100644
--- a/tools/perf/builtin-ftrace.c
+++ b/tools/perf/builtin-ftrace.c
@@ -840,7 +840,7 @@ static void display_histogram(struct perf_ftrace *ftrace, int buckets[])
 	bar_len = buckets[0] * bar_total / total;
 
 	printf("  %4d - %4d %s | %10d | %.*s%*s |\n",
-	       0, min_latency, use_nsec ? "ns" : "us",
+	       0, min_latency ?: 1, use_nsec ? "ns" : "us",
 	       buckets[0], bar_len, bar, bar_total - bar_len, "");
 
 	for (i = 1; i < NUM_BUCKET - 1; i++) {
-- 
2.47.1.613.gc27f4b7a9f-goog