From 587f05a88bd49c0c1f4c1b900787cedef461a902 Mon Sep 17 00:00:00 2001 From: "Luis Claudio R. Goncalves" Date: Wed, 12 Jun 2024 07:36:22 -0300 Subject: [PATCH] rtla/osnoise: Better report when histogram is empty When osnoise hist does not observe any samples above the threshold, no entries are recorded and the final report shows empty entries for the usual statistics (count, min, max, avg): [~]# osnoise hist -d 5s -T 500 # RTLA osnoise histogram # Time unit is microseconds (us) # Duration: 0 00:00:05 Index over: count: min: avg: max: That could lead users to confusing interpretations of the results. A simple solution is to report 0 for count and the statistics, making it clear that no noise (above the defined threshold) was observed: [~]# osnoise hist -d 5s -T 500 # RTLA osnoise histogram # Time unit is microseconds (us) # Duration: 0 00:00:05 Index over: 0 count: 0 min: 0 avg: 0 max: 0 Link: https://lkml.kernel.org/r/Zml6JmH5cbS7-HfZ@uudg.org Cc: Daniel Bristot de Oliveira Cc: John Kacur Cc: Clark Williams Reviewed-by: John Kacur Signed-off-by: Luis Claudio R. Goncalves Signed-off-by: Daniel Bristot de Oliveira --- tools/tracing/rtla/src/osnoise_hist.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c index 7be17d09f7e8..214e2c93fde0 100644 --- a/tools/tracing/rtla/src/osnoise_hist.c +++ b/tools/tracing/rtla/src/osnoise_hist.c @@ -374,6 +374,7 @@ osnoise_print_stats(struct osnoise_hist_params *params, struct osnoise_tool *too { struct osnoise_hist_data *data = tool->data; struct trace_instance *trace = &tool->trace; + int has_samples = 0; int bucket, cpu; int total; @@ -402,11 +403,25 @@ osnoise_print_stats(struct osnoise_hist_params *params, struct osnoise_tool *too continue; } + /* There are samples above the threshold */ + has_samples = 1; trace_seq_printf(trace->seq, "\n"); trace_seq_do_printf(trace->seq); trace_seq_reset(trace->seq); } + /* + * If no samples were recorded, skip calculations, print zeroed statistics + * and return. + */ + if (!has_samples) { + trace_seq_reset(trace->seq); + trace_seq_printf(trace->seq, "over: 0\ncount: 0\nmin: 0\navg: 0\nmax: 0\n"); + trace_seq_do_printf(trace->seq); + trace_seq_reset(trace->seq); + return; + } + if (!params->no_index) trace_seq_printf(trace->seq, "over: ");