Commit cff6d93e authored by Alice Ryhl's avatar Alice Ryhl Committed by Steven Rostedt (Google)
Browse files

tracepoint: Reduce duplication of __DO_TRACE_CALL 

The logic for invoking __DO_TRACE_CALL was extracted to a static inline
function called __rust_do_trace_##name so that Rust can call it
directly. This logic does not include the static branch, to avoid a
function call when the tracepoint is disabled.

Since the C code needs to perform the same logic after checking the
static key, this logic is currently duplicated. Thus, remove this
duplication by having C call the static inline function too.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20241212131237.1988409-1-aliceryhl@google.com


Signed-off-by: default avatarAlice Ryhl <aliceryhl@google.com>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 9e49ca75

include/linux/tracepoint.h

+7 −13
Original line number Diff line number Diff line
@@ -218,7 +218,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
#define __DEFINE_RUST_DO_TRACE(name, proto, args)			\

	notrace void rust_do_trace_##name(proto)			\

	{								\

		__rust_do_trace_##name(args);				\

		__do_trace_##name(args);				\

	}



/*
@@ -268,7 +268,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 


#define __DECLARE_TRACE(name, proto, args, cond, data_proto)		\

	__DECLARE_TRACE_COMMON(name, PARAMS(proto), PARAMS(args), PARAMS(data_proto)) \

	static inline void __rust_do_trace_##name(proto)		\

	static inline void __do_trace_##name(proto)			\

	{								\

		if (cond) {						\

			guard(preempt_notrace)();			\
@@ -277,12 +277,8 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
	}								\

	static inline void trace_##name(proto)				\

	{								\

		if (static_branch_unlikely(&__tracepoint_##name.key)) { \

			if (cond) {					\

				guard(preempt_notrace)();		\

				__DO_TRACE_CALL(name, TP_ARGS(args));	\

			}						\

		}							\

		if (static_branch_unlikely(&__tracepoint_##name.key))	\

			__do_trace_##name(args);			\

		if (IS_ENABLED(CONFIG_LOCKDEP) && (cond)) {		\

			WARN_ONCE(!rcu_is_watching(),			\

				  "RCU not watching for tracepoint");	\
@@ -291,7 +287,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 


#define __DECLARE_TRACE_SYSCALL(name, proto, args, data_proto)		\

	__DECLARE_TRACE_COMMON(name, PARAMS(proto), PARAMS(args), PARAMS(data_proto)) \

	static inline void __rust_do_trace_##name(proto)		\

	static inline void __do_trace_##name(proto)			\

	{								\

		guard(rcu_tasks_trace)();				\

		__DO_TRACE_CALL(name, TP_ARGS(args));			\
@@ -299,10 +295,8 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p) 
	static inline void trace_##name(proto)				\

	{								\

		might_fault();						\

		if (static_branch_unlikely(&__tracepoint_##name.key)) {	\

			guard(rcu_tasks_trace)();			\

			__DO_TRACE_CALL(name, TP_ARGS(args));		\

		}							\

		if (static_branch_unlikely(&__tracepoint_##name.key))	\

			__do_trace_##name(args);			\

		if (IS_ENABLED(CONFIG_LOCKDEP)) {			\

			WARN_ONCE(!rcu_is_watching(),			\

				  "RCU not watching for tracepoint");	\