Check the kretprobe maxactive is supported by kprobe_events
interface. To ensure the kernel feature, this changes ftrace
README to describe it.
Signed-off-by: Masami Hiramatsu <mhira...@kernel.org>
---
kernel/trace/trace.c | 3 ++-
.../ftrace/test.d/kprobe/kretprobe_maxactive.tc | 1 +
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1122f15..dc3f91e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4473,7 +4473,8 @@ static const char readme_msg[] =
#endif
#if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS)
"\t accepts: event-definitions (one definition per line)\n"
- "\t Format: p|r[:[<group>/]<event>] <place> [<args>]\n"
+ "\t Format: p[:[<group>/]<event>] <place> [<args>]\n"
+ "\t r[maxactive][:[<group>/]<event>] <place> [<args>]\n"
"\t -:[<group>/]<event>\n"
#ifdef CONFIG_KPROBE_EVENTS
"\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n"
diff --git
a/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_maxactive.tc
b/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_maxactive.tc
index 57abdf1..7ec6f26 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_maxactive.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kretprobe_maxactive.tc
@@ -2,6 +2,7 @@
# description: Kretprobe dynamic event with maxactive
[ -f kprobe_events ] || exit_unsupported # this is configurable
+grep -q 'r\[maxactive\]' README || exit_unsupported # this is older version
echo > kprobe_events
