Re: [PATCH v2 1/1] monitor/hmp: print trace as option in help for log command

[Markus Armbruster <armbru@redhat.com>]

Dongli Zhang <dongli.zhang@oracle.com> writes:

> The below is printed when printing help information in qemu-system-x86_64
> command line, and when CONFIG_TRACE_LOG is enabled:
>
> $ qemu-system-x86_64 -d help
> ... ...
> trace:PATTERN   enable trace events
>
> Use "-d trace:help" to get a list of trace events.
>
> However, they are not printed in hmp "help log" command.

This leaves me guessing what exactly the patch tries to do.

> Cc: Joe Jin <joe.jin@oracle.com>
> Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
> ---
> Changed since v1:
> - change format for "none" as well.
>
>  monitor/hmp.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/monitor/hmp.c b/monitor/hmp.c
> index 15ca047..467fc84 100644
> --- a/monitor/hmp.c
> +++ b/monitor/hmp.c
> @@ -285,10 +285,15 @@ void help_cmd(Monitor *mon, const char *name)
>          if (!strcmp(name, "log")) {
>              const QEMULogItem *item;
>              monitor_printf(mon, "Log items (comma separated):\n");
> -            monitor_printf(mon, "%-10s %s\n", "none", "remove all logs");
> +            monitor_printf(mon, "%-15s %s\n", "none", "remove all logs");
>              for (item = qemu_log_items; item->mask != 0; item++) {
> -                monitor_printf(mon, "%-10s %s\n", item->name, item->help);
> +                monitor_printf(mon, "%-15s %s\n", item->name, item->help);
>              }
> +#ifdef CONFIG_TRACE_LOG
> +            monitor_printf(mon, "trace:PATTERN   enable trace events\n");
> +            monitor_printf(mon, "\nUse \"info trace-events\" to get a list of "
> +                                "trace events.\n\n");

Aha: it fixes help to show "log trace:PATTERN".  Was that forgotten in
Paolo's commit c84ea00dc2 'log: add "-d trace:PATTERN"'?

"info trace-events", hmmm... it shows trace events and their state.
"log trace:help" also lists them, less their state, and in opposite
order.  Why do we need both?

What about showing them in alphabetical order?

> +#endif
>              return;
>          }