[v7,04/10] tracing/probes: Allow for dot delimiter as well as slash for system names

Commit Message

Steven Rostedt Aug. 19, 2021, 4:13 a.m. UTC

From: "Steven Rostedt (VMware)" <[e-mail]>

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/[e-mail]/
Link: https://lkml.kernel.org/r/[e-mail]

Suggested-by: Masami Hiramatsu <[e-mail]>
Acked-by: Masami Hiramatsu <[e-mail]>
Signed-off-by: Steven Rostedt (VMware) <[e-mail]>
---
 kernel/trace/trace_probe.c | 3 +++
 1 file changed, 3 insertions(+)

Patch

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);