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

While working on a clean up that would restructure the difference between
architectures that have static calls vs those that do not, I was stumbling
over the "data_args" parameter that includes "__data" in the arguments. The
issue was that one version didn't even need it, while the other one did.
Instead of injecting a "__data = NULL;" into the macro for the unneeded
version, just remove it completely.

The original idea behind data_args is that there may be a case of a
tracepoint with no arguments. But this is considered bad practice, and all
tracepoints should pass something to that location (that's what tracepoints
were created for).

Signed-off-by: Steven Rostedt (VMware) <rost...@goodmis.org>
---
 include/linux/tracepoint.h | 31 +++++++++++--------------------
 1 file changed, 11 insertions(+), 20 deletions(-)

diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index 966ed8980327..42bb5b753b33 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -160,13 +160,8 @@ static inline struct tracepoint 
*tracepoint_ptr_deref(tracepoint_ptr_t *p)
 /*
  * it_func[0] is never NULL because there is at least one element in the array
  * when the array itself is non NULL.
- *
- * Note, the proto and args passed in includes "__data" as the first parameter.
- * The reason for this is to handle the "void" prototype. If a tracepoint
- * has a "void" prototype, then it is invalid to declare a function
- * as "(void *, void)".
  */
-#define __DO_TRACE(name, proto, args, cond, rcuidle)                   \
+#define __DO_TRACE(name, args, cond, rcuidle)                          \
        do {                                                            \
                struct tracepoint_func *it_func_ptr;                    \
                int __maybe_unused __idx = 0;                           \
@@ -194,7 +189,7 @@ static inline struct tracepoint 
*tracepoint_ptr_deref(tracepoint_ptr_t *p)
                        rcu_dereference_raw((&__tracepoint_##name)->funcs); \
                if (it_func_ptr) {                                      \
                        __data = (it_func_ptr)->data;                   \
-                       __DO_TRACE_CALL(name)(args);                    \
+                       __DO_TRACE_CALL(name)(__data, args);            \
                }                                                       \
                                                                        \
                if (rcuidle) {                                          \
@@ -206,17 +201,16 @@ static inline struct tracepoint 
*tracepoint_ptr_deref(tracepoint_ptr_t *p)
        } while (0)
 
 #ifndef MODULE
-#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args) \
+#define __DECLARE_TRACE_RCU(name, proto, args, cond)                   \
        static inline void trace_##name##_rcuidle(proto)                \
        {                                                               \
                if (static_key_false(&__tracepoint_##name.key))         \
                        __DO_TRACE(name,                                \
-                               TP_PROTO(data_proto),                   \
-                               TP_ARGS(data_args),                     \
+                               TP_ARGS(args),                          \
                                TP_CONDITION(cond), 1);                 \
        }
 #else
-#define __DECLARE_TRACE_RCU(name, proto, args, cond, data_proto, data_args)
+#define __DECLARE_TRACE_RCU(name, proto, args, cond)
 #endif
 
 /*
@@ -231,7 +225,7 @@ static inline struct tracepoint 
*tracepoint_ptr_deref(tracepoint_ptr_t *p)
  * even when this tracepoint is off. This code has no purpose other than
  * poking RCU a bit.
  */
-#define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \
+#define __DECLARE_TRACE(name, proto, args, cond, data_proto)           \
        extern int __traceiter_##name(data_proto);                      \
        DECLARE_STATIC_CALL(tp_func_##name, __traceiter_##name);        \
        extern struct tracepoint __tracepoint_##name;                   \
@@ -239,8 +233,7 @@ static inline struct tracepoint 
*tracepoint_ptr_deref(tracepoint_ptr_t *p)
        {                                                               \
                if (static_key_false(&__tracepoint_##name.key))         \
                        __DO_TRACE(name,                                \
-                               TP_PROTO(data_proto),                   \
-                               TP_ARGS(data_args),                     \
+                               TP_ARGS(args),                          \
                                TP_CONDITION(cond), 0);                 \
                if (IS_ENABLED(CONFIG_LOCKDEP) && (cond)) {             \
                        rcu_read_lock_sched_notrace();                  \
@@ -249,7 +242,7 @@ static inline struct tracepoint 
*tracepoint_ptr_deref(tracepoint_ptr_t *p)
                }                                                       \
        }                                                               \
        __DECLARE_TRACE_RCU(name, PARAMS(proto), PARAMS(args),          \
-               PARAMS(cond), PARAMS(data_proto), PARAMS(data_args))    \
+                           PARAMS(cond))                               \
        static inline int                                               \
        register_trace_##name(void (*probe)(data_proto), void *data)    \
        {                                                               \
@@ -332,7 +325,7 @@ static inline struct tracepoint 
*tracepoint_ptr_deref(tracepoint_ptr_t *p)
 
 
 #else /* !TRACEPOINTS_ENABLED */
-#define __DECLARE_TRACE(name, proto, args, cond, data_proto, data_args) \
+#define __DECLARE_TRACE(name, proto, args, cond, data_proto)           \
        static inline void trace_##name(proto)                          \
        { }                                                             \
        static inline void trace_##name##_rcuidle(proto)                \
@@ -412,14 +405,12 @@ static inline struct tracepoint 
*tracepoint_ptr_deref(tracepoint_ptr_t *p)
 #define DECLARE_TRACE(name, proto, args)                               \
        __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args),              \
                        cpu_online(raw_smp_processor_id()),             \
-                       PARAMS(void *__data, proto),                    \
-                       PARAMS(__data, args))
+                       PARAMS(void *__data, proto))
 
 #define DECLARE_TRACE_CONDITION(name, proto, args, cond)               \
        __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args),              \
                        cpu_online(raw_smp_processor_id()) && (PARAMS(cond)), \
-                       PARAMS(void *__data, proto),                    \
-                       PARAMS(__data, args))
+                       PARAMS(void *__data, proto))
 
 #define TRACE_EVENT_FLAGS(event, flag)
 
-- 
2.29.2


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