Re: [PATCH v9 1/5] rust: add generic static_key_false

From
Steven Rostedt <rostedt@goodmis.org>
Date
2024-10-01 21:45:22
Also in
linux-arch, linux-riscv, lkml, loongarch, rust-for-linux
Reply to
Josh Poimboeuf, 2024-10-01
On Tue, 1 Oct 2024 14:15:43 -0700
Josh Poimboeuf [off-list ref] wrote:
On Tue, Oct 01, 2024 at 01:29:58PM +0000, Alice Ryhl wrote:
quoted
Add just enough support for static key so that we can use it from
tracepoints. Tracepoints rely on `static_key_false` even though it is
deprecated, so we add the same functionality to Rust.  
Instead of extending the old deprecated static key interface into Rust,
can we just change tracepoints to use the new one?
Sure, care to send the patch properly, and I can add it to my queue.

-- Steve
quoted hunk ↗ jump to hunk
/me makes a note to go convert the other users...

From: Josh Poimboeuf <jpoimboe@kernel.org>
Subject: [PATCH] tracepoints: Use new static branch API

The old static key API based on 'struct static_key' is deprecated.
Convert tracepoints to use the new API.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
 include/linux/tracepoint-defs.h | 4 ++--
 include/linux/tracepoint.h      | 8 ++++----
 kernel/tracepoint.c             | 4 ++--
 3 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/include/linux/tracepoint-defs.h b/include/linux/tracepoint-defs.h
index 4dc4955f0fbf..60a6e8314d4c 100644
--- a/include/linux/tracepoint-defs.h
+++ b/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
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 6be396bb4297..ab5162fc3e4a 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -228,7 +228,7 @@ 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);			\
@@ -254,7 +254,7 @@ 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);			\
@@ -291,7 +291,7 @@ 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);\
 	}
 
 /*
@@ -308,7 +308,7 @@ 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,			\
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 8d1507dd0724..dc160cc0b616 100644
--- a/kernel/tracepoint.c
+++ b/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 */
  
Thread (17 messages) 17 messages, 4 authors, last reply 2024-10-11
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