tracepoints: Use new static branch API

The old static key API is deprecated.  Switch to the new one.

Cc: Masami Hiramatsu <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Alice Ryhl <[email protected]>
Link: https://lore.kernel.org/7a08dae3c5eddb14b13864923c1b58ac1f4af83c.1728414936.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

Author: jpoimboe

include/linux/tracepoint-defs.h

@@ -31,7 +31,7 @@ struct tracepoint_func {
 
 struct tracepoint {
 	const char *name;		/* Tracepoint name */
-	struct static_key key;
+	struct static_key_false key;
 	struct static_call_key *static_call_key;
 	void *static_call_tramp;
 	void *iterator;
@@ -83,7 +83,7 @@ struct bpf_raw_event_map {
 
 #ifdef CONFIG_TRACEPOINTS
 # define tracepoint_enabled(tp) \
-	static_key_false(&(__tracepoint_##tp).key)
+	static_branch_unlikely(&(__tracepoint_##tp).key)
 #else
 # define tracepoint_enabled(tracepoint) false
 #endif

include/linux/tracepoint.h

@@ -248,7 +248,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
 #define __DECLARE_TRACE_RCU(name, proto, args, cond)			\
 	static inline void trace_##name##_rcuidle(proto)		\
 	{								\
-		if (static_key_false(&__tracepoint_##name.key))		\
+		if (static_branch_unlikely(&__tracepoint_##name.key))	\
 			__DO_TRACE(name,				\
 				TP_ARGS(args),				\
 				TP_CONDITION(cond), 1);			\
@@ -274,7 +274,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
 	extern struct tracepoint __tracepoint_##name;			\
 	static inline void trace_##name(proto)				\
 	{								\
-		if (static_key_false(&__tracepoint_##name.key))		\
+		if (static_branch_unlikely(&__tracepoint_##name.key))	\
 			__DO_TRACE(name,				\
 				TP_ARGS(args),				\
 				TP_CONDITION(cond), 0);			\
@@ -311,7 +311,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
 	static inline bool						\
 	trace_##name##_enabled(void)					\
 	{								\
-		return static_key_false(&__tracepoint_##name.key);	\
+		return static_branch_unlikely(&__tracepoint_##name.key);\
 	}
 
 /*
@@ -328,7 +328,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
 	struct tracepoint __tracepoint_##_name	__used			\
 	__section("__tracepoints") = {					\
 		.name = __tpstrtab_##_name,				\
-		.key = STATIC_KEY_INIT_FALSE,				\
+		.key = STATIC_KEY_FALSE_INIT,				\
 		.static_call_key = &STATIC_CALL_KEY(tp_func_##_name),	\
 		.static_call_tramp = STATIC_CALL_TRAMP_ADDR(tp_func_##_name), \
 		.iterator = &__traceiter_##_name,			\

kernel/trace/trace_events_hist.c

@@ -822,7 +822,7 @@ static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals,
 {
 	struct tracepoint *tp = event->tp;
 
-	if (unlikely(atomic_read(&tp->key.enabled) > 0)) {
+	if (unlikely(static_key_enabled(&tp->key))) {
 		struct tracepoint_func *probe_func_ptr;
 		synth_probe_func_t probe_func;
 		void *__data;

kernel/trace/trace_events_user.c

@@ -1676,7 +1676,7 @@ static void update_enable_bit_for(struct user_event *user)
 	struct tracepoint *tp = &user->tracepoint;
 	char status = 0;
 
-	if (atomic_read(&tp->key.enabled) > 0) {
+	if (static_key_enabled(&tp->key)) {
 		struct tracepoint_func *probe_func_ptr;
 		user_event_func_t probe_func;
 
@@ -2280,7 +2280,7 @@ static ssize_t user_events_write_core(struct file *file, struct iov_iter *i)
 	 * It's possible key.enabled disables after this check, however
 	 * we don't mind if a few events are included in this condition.
 	 */
-	if (likely(atomic_read(&tp->key.enabled) > 0)) {
+	if (likely(static_key_enabled(&tp->key))) {
 		struct tracepoint_func *probe_func_ptr;
 		user_event_func_t probe_func;
 		struct iov_iter copy;

kernel/tracepoint.c

@@ -358,7 +358,7 @@ static int tracepoint_add_func(struct tracepoint *tp,
 		tracepoint_update_call(tp, tp_funcs);
 		/* Both iterator and static call handle NULL tp->funcs */
 		rcu_assign_pointer(tp->funcs, tp_funcs);
-		static_key_enable(&tp->key);
+		static_branch_enable(&tp->key);
 		break;
 	case TP_FUNC_2:		/* 1->2 */
 		/* Set iterator static call */
@@ -414,7 +414,7 @@ static int tracepoint_remove_func(struct tracepoint *tp,
 		if (tp->unregfunc && static_key_enabled(&tp->key))
 			tp->unregfunc();
 
-		static_key_disable(&tp->key);
+		static_branch_disable(&tp->key);
 		/* Set iterator static call */
 		tracepoint_update_call(tp, tp_funcs);
 		/* Both iterator and static call handle NULL tp->funcs */