tracing: Fix for sparse warnings and anonymous unions

PATCH New Steven Rostedt 1 participant 3 messages Apr 10, 2014

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Tracing ABI/API ftrace

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Steven Rostedt

author maintainer

2014-04-10 13:01 UTC #0 lore raw

cover tracing: Fix for sparse warnings and anonymous unions

git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
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Head SHA1: abb43f6998eb6466ea392d3757e673bbdb6ae171

Mathieu Desnoyers (2):
tracepoint: Fix sparse warnings in tracepoint.c
tracing: Fix anonymous unions in struct ftrace_event_call

----

 include/linux/syscalls.h        |  8 ++++++--
 include/linux/tracepoint.h      |  5 +++++
 include/trace/events/syscalls.h |  3 ---
 include/trace/ftrace.h          | 12 +++++++++---
 kernel/trace/trace_export.c     |  6 ++++--
 kernel/tracepoint.c             |  6 ++++--
 6 files changed, 28 insertions(+), 12 deletions(-)

Steven Rostedt

author maintainer

2014-04-10 13:01 UTC #1 lore raw

PATCH 1/2 tracepoint: Fix sparse warnings in tracepoint.c

From: Mathieu Desnoyers <[email protected]>

Fix the following sparse warnings:

CHECK kernel/tracepoint.c
kernel/tracepoint.c:184:18: warning: incorrect type in assignment (different address spaces)
kernel/tracepoint.c:184:18: expected struct tracepoint_func *tp_funcs
kernel/tracepoint.c:184:18: got struct tracepoint_func [noderef] <asn:4>*funcs
kernel/tracepoint.c:216:18: warning: incorrect type in assignment (different address spaces)
kernel/tracepoint.c:216:18: expected struct tracepoint_func *tp_funcs
kernel/tracepoint.c:216:18: got struct tracepoint_func [noderef] <asn:4>*funcs
kernel/tracepoint.c:392:24: error: return expression in void function
CC kernel/tracepoint.o
kernel/tracepoint.c: In function tracepoint_module_going:
kernel/tracepoint.c:491:6: warning: symbol 'syscall_regfunc' was not declared. Should it be static? kernel/tracepoint.c:508:6: warning: symbol 'syscall_unregfunc' was not declared. Should it be static?

Link http://lkml.kernel.org/r/[email protected] open here

Signed-off-by Mathieu Desnoyers <[email protected]>

Signed-off-by Steven Rostedt <[email protected]>

---
 include/linux/tracepoint.h      | 5 +++++
 include/trace/events/syscalls.h | 3 ---
 kernel/tracepoint.c             | 6 ++++--
 3 files changed, 9 insertions(+), 5 deletions(-)

include/linux/tracepoint.h +5 -0

index 69a298b..9d30ee4 100644
@@ -80,6 +80,11 @@ static inline void tracepoint_synchronize_unregister(void)
 	synchronize_sched();
 }
 
+#ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
+extern void syscall_regfunc(void);
+extern void syscall_unregfunc(void);
+#endif /* CONFIG_HAVE_SYSCALL_TRACEPOINTS */
+
 #define PARAMS(args...) args
 
 #endif /* _LINUX_TRACEPOINT_H */

include/trace/events/syscalls.h +0 -3

index 5a4c04a..14e49c7 100644
@@ -13,9 +13,6 @@
 
 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
 
-extern void syscall_regfunc(void);
-extern void syscall_unregfunc(void);
-
 TRACE_EVENT_FN(sys_enter,
 
 	TP_PROTO(struct pt_regs *regs, long id),

kernel/tracepoint.c +4 -2

index 162be19..ca2cfe2 100644
@@ -181,7 +181,8 @@ static int tracepoint_add_func(struct tracepoint *tp,
 	if (tp->regfunc && !static_key_enabled(&tp->key))
 		tp->regfunc();
 
-	tp_funcs = tp->funcs;
+	tp_funcs = rcu_dereference_protected(tp->funcs,
+			lockdep_is_held(&tracepoints_mutex));
 	old = func_add(&tp_funcs, func);
 	if (IS_ERR(old)) {
 		WARN_ON_ONCE(1);

@@ -213,7 +214,8 @@ static int tracepoint_remove_func(struct tracepoint *tp,
 {
 	struct tracepoint_func *old, *tp_funcs;
 
-	tp_funcs = tp->funcs;
+	tp_funcs = rcu_dereference_protected(tp->funcs,
+			lockdep_is_held(&tracepoints_mutex));
 	old = func_remove(&tp_funcs, func);
 	if (IS_ERR(old)) {
 		WARN_ON_ONCE(1);

Signature · 1 line

1.8.5.3

Steven Rostedt

author maintainer

2014-04-10 13:01 UTC #2 lore raw

PATCH 2/2 tracing: Fix anonymous unions in struct ftrace_event_call

In reply to Steven Rostedt

From: Mathieu Desnoyers <[email protected]>

gcc <= 4.5.x has significant limitations with respect to initialization of anonymous unions within structures. They need to be surrounded by brackets, _and_ they need to be initialized in the same order in which they appear in the structure declaration.

Link http://gcc.gnu.org/bugzilla/show_bug.cgi?id=10676

Link http://lkml.kernel.org/r/[email protected] open here

Signed-off-by Mathieu Desnoyers <[email protected]>

Signed-off-by Steven Rostedt <[email protected]>

---
 include/linux/syscalls.h    |  8 ++++++--
 include/trace/ftrace.h      | 12 +++++++++---
 kernel/trace/trace_export.c |  6 ++++--
 3 files changed, 19 insertions(+), 7 deletions(-)

include/linux/syscalls.h +6 -2

index 1e67b7a..af94c98 100644
@@ -119,8 +119,10 @@ extern struct trace_event_functions exit_syscall_print_funcs;
 	static struct syscall_metadata __syscall_meta_##sname;		\
 	static struct ftrace_event_call __used				\
 	  event_enter_##sname = {					\
-		.name                   = "sys_enter"#sname,		\
 		.class			= &event_class_syscall_enter,	\
+		{							\
+			.name                   = "sys_enter"#sname,	\
+		},							\
 		.event.funcs            = &enter_syscall_print_funcs,	\
 		.data			= (void *)&__syscall_meta_##sname,\
 		.flags                  = TRACE_EVENT_FL_CAP_ANY,	\

@@ -133,8 +135,10 @@ extern struct trace_event_functions exit_syscall_print_funcs;
 	static struct syscall_metadata __syscall_meta_##sname;		\
 	static struct ftrace_event_call __used				\
 	  event_exit_##sname = {					\
-		.name                   = "sys_exit"#sname,		\
 		.class			= &event_class_syscall_exit,	\
+		{							\
+			.name                   = "sys_exit"#sname,	\
+		},							\
 		.event.funcs		= &exit_syscall_print_funcs,	\
 		.data			= (void *)&__syscall_meta_##sname,\
 		.flags                  = TRACE_EVENT_FL_CAP_ANY,	\

include/trace/ftrace.h +9 -3

index 9c44c11..0a1a4f7 100644
@@ -470,8 +470,10 @@ static inline notrace int ftrace_get_offsets_##call(			\
  * };
  *
  * static struct ftrace_event_call event_<call> = {
- *	.tp			= &__tracepoint_<call>,
  *	.class			= event_class_<template>,
+ *	{
+ *		.tp			= &__tracepoint_<call>,
+ *	},
  *	.event			= &ftrace_event_type_<call>,
  *	.print_fmt		= print_fmt_<call>,
  *	.flags			= TRACE_EVENT_FL_TRACEPOINT,

@@ -606,8 +608,10 @@ static struct ftrace_event_class __used __refdata event_class_##call = { \
 #define DEFINE_EVENT(template, call, proto, args)			\
 									\
 static struct ftrace_event_call __used event_##call = {			\
-	.tp			= &__tracepoint_##call,			\
 	.class			= &event_class_##template,		\
+	{								\
+		.tp			= &__tracepoint_##call,		\
+	},								\
 	.event.funcs		= &ftrace_event_type_funcs_##template,	\
 	.print_fmt		= print_fmt_##template,			\
 	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\

@@ -621,8 +625,10 @@ __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
 static const char print_fmt_##call[] = print;				\
 									\
 static struct ftrace_event_call __used event_##call = {			\
-	.tp			= &__tracepoint_##call,			\
 	.class			= &event_class_##template,		\
+	{								\
+		.tp			= &__tracepoint_##call,		\
+	},								\
 	.event.funcs		= &ftrace_event_type_funcs_##call,	\
 	.print_fmt		= print_fmt_##call,			\
 	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\

kernel/trace/trace_export.c +4 -2

index ee0a509..d4ddde2 100644
@@ -173,9 +173,11 @@ struct ftrace_event_class __refdata event_class_ftrace_##call = {	\
 };									\
 									\
 struct ftrace_event_call __used event_##call = {			\
-	.name			= #call,				\
-	.event.type		= etype,				\
 	.class			= &event_class_ftrace_##call,		\
+	{								\
+		.name			= #call,			\
+	},								\
+	.event.type		= etype,				\
 	.print_fmt		= print,				\
 	.flags			= TRACE_EVENT_FL_IGNORE_ENABLE | TRACE_EVENT_FL_USE_CALL_FILTER, \
 };									\

Signature · 1 line

1.8.5.3