Re: [PATCH 3/3] rtla: Parse cmdline using libsubcmd

[Costa Shulyupin]

On Fri, 20 Mar 2026 at 17:07, Tomas Glozar <tglo...@redhat.com> wrote:
>> +#define TIMERLAT_OPT_NANO OPT_CALLBACK('n', "nano", params, NULL, \
> +       "display data in nanoseconds", \
> +       opt_nano_cb)

-n/--nano requires value incorrectly

 File: src/cli.c:463
 Cause: TIMERLAT_OPT_NANO used OPT_CALLBACK which expects an argument,
but -n is a flag.
 Fix: Changed to OPT_CALLBACK_NOOPT:

> +               HIST_OPT_NO_IRQ,
--no-irq clashes with auto-negation of --irq

 File: src/cli.c:1042
 Cause: libsubcmd auto-generates --no-X negations for every option.
--no-irq (histogram boolean) collides with the auto-negation of --irq
(stop threshold). The first match wins, so --irq was matched first and
its negation intercepted the call.
 Fix: Moved HIST_OPT_NO_IRQ before RTLA_OPT_STOP('i', "irq", ...) in
the options array so the explicit --no-irq boolean is found first.

> +               HIST_OPT_NO_THREAD,
--no-thread - same issue

 Cause: Same collision between --no-thread boolean and auto-negation
of --thread.
 Fix: Same reordering approach.

Costa and Claude

diff --git a/tools/tracing/rtla/src/cli.c b/tools/tracing/rtla/src/cli.c
index d029a698e8a7..c6b9ed920539 100644
--- a/tools/tracing/rtla/src/cli.c
+++ b/tools/tracing/rtla/src/cli.c
@@ -460,7 +460,7 @@ static int opt_osnoise_on_end_cb(const struct
option *opt, const char *arg, int
  "save the stack trace at the IRQ if a thread latency is higher than
the argument in us", \
  opt_llong_callback)

-#define TIMERLAT_OPT_NANO OPT_CALLBACK('n', "nano", params, NULL, \
+#define TIMERLAT_OPT_NANO OPT_CALLBACK_NOOPT('n', "nano", params, NULL, \
  "display data in nanoseconds", \
  opt_nano_cb)

@@ -1011,6 +1011,12 @@ struct common_params
*timerlat_hist_parse_args(int argc, char **argv)
  cb_data.trace_output = NULL;

  const struct option timerlat_hist_options[] = {
+ OPT_GROUP("Histogram Options:"),
+ HIST_OPT_NO_IRQ,
+ HIST_OPT_NO_THREAD,
+ HIST_OPT_BUCKET_SIZE,
+ HIST_OPT_ENTRIES,
+
  OPT_GROUP("Tracing Options:"),
  TIMERLAT_OPT_PERIOD,
  RTLA_OPT_STOP('i', "irq", "irq latency"),
@@ -1034,11 +1040,7 @@ struct common_params
*timerlat_hist_parse_args(int argc, char **argv)
  RTLA_OPT_KERNEL_THREADS,
  RTLA_OPT_USER_LOAD,

- OPT_GROUP("Histogram Options:"),
- HIST_OPT_BUCKET_SIZE,
- HIST_OPT_ENTRIES,
- HIST_OPT_NO_IRQ,
- HIST_OPT_NO_THREAD,
+ OPT_GROUP(""),
  HIST_OPT_NO_HEADER,
  HIST_OPT_NO_SUMMARY,
 HIST_OPT_NO_INDEX,