[PATCH 4.19.y 05/13] tracing: Consolidate trace_add/remove_event_call back to the nolock functions

George Guo
2024-05-09T02:30:16Z

From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>

commit 7e1413edd6194a9807aa5f3ac0378b9b4b9da879 upstream.

The trace_add/remove_event_call_nolock() functions were added to allow
the tace_add/remove_event_call() code be called when the event_mutex
lock was already taken. Now that all callers are done within the
event_mutex, there's no reason to have two different interfaces.

Remove the current wrapper trace_add/remove_event_call()s and rename the
_nolock versions back to the original names.

Link: http://lkml.kernel.org/r/154140866955.17322.2081425494660638846.stgit@devbox

Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: George Guo <guodongtai@kylinos.cn>
---
include/linux/trace_events.h | 2 --
kernel/trace/trace_events.c | 30 ++++--------------------------
kernel/trace/trace_events_hist.c | 6 +++---
3 files changed, 7 insertions(+), 31 deletions(-)

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 755daada7def..f4077379420f 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -529,8 +529,6 @@ extern int trace_event_raw_init(struct trace_event_call *call);
extern int trace_define_field(struct trace_event_call *call, const char *type,
const char *name, int offset, int size,
int is_signed, int filter_type);
-extern int trace_add_event_call_nolock(struct trace_event_call *call);
-extern int trace_remove_event_call_nolock(struct trace_event_call *call);
extern int trace_add_event_call(struct trace_event_call *call);
extern int trace_remove_event_call(struct trace_event_call *call);
extern int trace_event_get_offsets(struct trace_event_call *call);
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 2830a9cbe648..949eac9362a6 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2312,7 +2312,8 @@ __trace_early_add_new_event(struct trace_event_call *call,
struct ftrace_module_file_ops;
static void __add_event_to_tracers(struct trace_event_call *call);

-int trace_add_event_call_nolock(struct trace_event_call *call)
+/* Add an additional event_call dynamically */
+int trace_add_event_call(struct trace_event_call *call)
{
int ret;
lockdep_assert_held(&event_mutex);
@@ -2327,17 +2328,6 @@ int trace_add_event_call_nolock(struct trace_event_call *call)
return ret;
}

-/* Add an additional event_call dynamically */
-int trace_add_event_call(struct trace_event_call *call)
-{
- int ret;
-
- mutex_lock(&event_mutex);
- ret = trace_add_event_call_nolock(call);
- mutex_unlock(&event_mutex);
- return ret;
-}
-
/*
* Must be called under locking of trace_types_lock, event_mutex and
* trace_event_sem.
@@ -2383,8 +2373,8 @@ static int probe_remove_event_call(struct trace_event_call *call)
return 0;
}

-/* no event_mutex version */
-int trace_remove_event_call_nolock(struct trace_event_call *call)
+/* Remove an event_call */
+int trace_remove_event_call(struct trace_event_call *call)
{
int ret;

@@ -2399,18 +2389,6 @@ int trace_remove_event_call_nolock(struct trace_event_call *call)
return ret;
}

-/* Remove an event_call */
-int trace_remove_event_call(struct trace_event_call *call)
-{
- int ret;
-
- mutex_lock(&event_mutex);
- ret = trace_remove_event_call_nolock(call);
- mutex_unlock(&event_mutex);
-
- return ret;
-}
-
#define for_each_event(event, start, end) \
for (event = start; \
(unsigned long)event < (unsigned long)end; \
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 1a32b64d350b..1139075a6395 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -980,7 +980,7 @@ static int register_synth_event(struct synth_event *event)
call->data = event;
call->tp = event->tp;

- ret = trace_add_event_call_nolock(call);
+ ret = trace_add_event_call(call);
if (ret) {
pr_warn("Failed to register synthetic event: %s\n",
trace_event_name(call));
@@ -989,7 +989,7 @@ static int register_synth_event(struct synth_event *event)

ret = set_synth_event_print_fmt(call);
if (ret < 0) {
- trace_remove_event_call_nolock(call);
+ trace_remove_event_call(call);
goto err;
}
out:
@@ -1004,7 +1004,7 @@ static int unregister_synth_event(struct synth_event *event)
struct trace_event_call *call = &event->call;
int ret;

- ret = trace_remove_event_call_nolock(call);
+ ret = trace_remove_event_call(call);

return ret;
}
--
2.34.1