From 510f0247cdac26dfc2fed6e712f3cb616da49b5c Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Wed, 8 Jan 2025 13:00:15 -0800 Subject: [PATCH] perf ftrace: Fix display for range of the first bucket 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: 08b875b6bf608589 ("perf ftrace latency: Introduce --min-latency to narrow down into a latency range") Reviewed-by: Gabriele Monaco Signed-off-by: Namhyung Kim Tested-by: Arnaldo Carvalho de Melo Tested-by: Gabriele Monaco Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20250108210015.1188531-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- 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 90cf2c9915a7..cfd770ec7286 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++) { -- 2.25.1