From de7b2973903c6cc50b31ee5682a69b2219b9919d Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Tue, 8 Apr 2014 17:26:21 -0400
Subject: tracepoint: Use struct pointer instead of name hash for reg/unreg
 tracepoints

Register/unregister tracepoint probes with struct tracepoint pointer
rather than tracepoint name.

This change, which vastly simplifies tracepoint.c, has been proposed by
Steven Rostedt. It also removes 8.8kB (mostly of text) to the vmlinux
size.

From this point on, the tracers need to pass a struct tracepoint pointer
to probe register/unregister. A probe can now only be connected to a
tracepoint that exists. Moreover, tracers are responsible for
unregistering the probe before the module containing its associated
tracepoint is unloaded.

   text    data     bss     dec     hex filename
10443444        4282528 10391552        25117524        17f4354 vmlinux.orig
10434930        4282848 10391552        25109330        17f2352 vmlinux

Link: http://lkml.kernel.org/r/1396992381-23785-2-git-send-email-mathieu.desnoyers@efficios.com

CC: Ingo Molnar <mingo@kernel.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Frank Ch. Eigler <fche@redhat.com>
CC: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
[ SDR - fixed return val in void func in tracepoint_module_going() ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/trace/ftrace.h | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

(limited to 'include/trace')

diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 8765126b328c..9c44c11cd9bb 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -470,10 +470,11 @@ static inline notrace int ftrace_get_offsets_##call(			\
  * };
  *
  * static struct ftrace_event_call event_<call> = {
- *	.name			= "<call>",
+ *	.tp			= &__tracepoint_<call>,
  *	.class			= event_class_<template>,
  *	.event			= &ftrace_event_type_<call>,
  *	.print_fmt		= print_fmt_<call>,
+ *	.flags			= TRACE_EVENT_FL_TRACEPOINT,
  * };
  * // its only safe to use pointers when doing linker tricks to
  * // create an array.
@@ -605,10 +606,11 @@ 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 = {			\
-	.name			= #call,				\
+	.tp			= &__tracepoint_##call,			\
 	.class			= &event_class_##template,		\
 	.event.funcs		= &ftrace_event_type_funcs_##template,	\
 	.print_fmt		= print_fmt_##template,			\
+	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\
 };									\
 static struct ftrace_event_call __used					\
 __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
@@ -619,10 +621,11 @@ __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
 static const char print_fmt_##call[] = print;				\
 									\
 static struct ftrace_event_call __used event_##call = {			\
-	.name			= #call,				\
+	.tp			= &__tracepoint_##call,			\
 	.class			= &event_class_##template,		\
 	.event.funcs		= &ftrace_event_type_funcs_##call,	\
 	.print_fmt		= print_fmt_##call,			\
+	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\
 };									\
 static struct ftrace_event_call __used					\
 __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
-- 
cgit v1.2.3


From b725dfea24b89de672c055b34b22398283a3f4bc Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Wed, 9 Apr 2014 09:24:43 -0400
Subject: tracepoint: Fix sparse warnings in tracepoint.c

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/1397049883-28692-1-git-send-email-mathieu.desnoyers@efficios.com

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/trace/events/syscalls.h | 3 ---
 1 file changed, 3 deletions(-)

(limited to 'include/trace')

diff --git a/include/trace/events/syscalls.h b/include/trace/events/syscalls.h
index 5a4c04a75b3d..14e49c798135 100644
--- a/include/trace/events/syscalls.h
+++ b/include/trace/events/syscalls.h
@@ -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),
-- 
cgit v1.2.3


From abb43f6998eb6466ea392d3757e673bbdb6ae171 Mon Sep 17 00:00:00 2001
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Wed, 9 Apr 2014 17:06:08 -0400
Subject: tracing: Fix anonymous unions in struct ftrace_event_call

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/1397077568-3156-1-git-send-email-mathieu.desnoyers@efficios.com

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/trace/ftrace.h | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

(limited to 'include/trace')

diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 9c44c11cd9bb..0a1a4f7caf09 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -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,		\
-- 
cgit v1.2.3