Re: [PATCH v6 4/7] tracing/probes: Allow for dot delimiter as well as slash for system names

From: Masami Hiramatsu
Date: Wed Aug 18 2021 - 06:57:18 EST


On Mon, 16 Aug 2021 23:42:59 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
>
> Kprobe and uprobe events can add a "system" to the events that are created
> via the kprobe_events and uprobe_events files respectively. If they do not
> include a "system" in the name, then the default "kprobes" or "uprobes" is
> used. The current notation to specify a system for one of these probe
> events is to add a '/' delimiter in the name, where the content before the
> '/' will be the system to use, and the content after will be the event
> name.
>
> echo 'p:my_system/my_event' > kprobe_events
>
> But this is inconsistent with the way histogram triggers separate their
> system / event names. The histogram triggers use a '.' delimiter, which
> can be confusing.
>
> To allow this to be more consistent, as well as keep backward
> compatibility, allow the kprobe and uprobe events to denote a system name
> with either a '/' or a '.'.
>
> That is:
>
> echo 'p:my_system/my_event' > kprobe_events
>
> is equivalent to:
>
> echo 'p:my_system.my_event' > kprobe_events
>
> Link: https://lore.kernel.org/linux-trace-devel/20210813004448.51c7de69ce432d338f4d226b@xxxxxxxxxx/
>

Yes, this is what I suggested :)

Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

Thanks!


> Suggested-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> ---
> kernel/trace/trace_probe.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
> index ef717b373443..0916a9964719 100644
> --- a/kernel/trace/trace_probe.c
> +++ b/kernel/trace/trace_probe.c
> @@ -233,6 +233,9 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
> int len;
>
> slash = strchr(event, '/');
> + if (!slash)
> + slash = strchr(event, '.');
> +
> if (slash) {
> if (slash == event) {
> trace_probe_log_err(offset, NO_GROUP_NAME);
> --
> 2.30.2


--
Masami Hiramatsu <mhiramat@xxxxxxxxxx>