[PATCH v2][GIT PULL][v3.5] ftrace: Make all inline tags also include notrace

[Steven Rostedt <rostedt@goodmis.org>]

Ingo,

I updated the change log as you recommended, there was no code change.

-- Steve

Please pull the latest tip/perf/urgent-2 tree, which can be found at:

  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace.git
tip/perf/urgent-2

Head SHA1: 93b3cca1ccd30b1ad290951a3fc7c10c73db7313


Steven Rostedt (1):
      ftrace: Make all inline tags also include notrace

----
 include/linux/compiler-gcc.h |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---------------------------
commit 93b3cca1ccd30b1ad290951a3fc7c10c73db7313
Author: Steven Rostedt <rostedt@goodmis.org>
Date:   Thu Jun 14 10:54:28 2012 -0400

    ftrace: Make all inline tags also include notrace
    
    Commit 5963e317b1e9d2a ("ftrace/x86: Do not change stacks in DEBUG when
    calling lockdep") prevented lockdep calls from the int3 breakpoint handler
    from reseting the stack if a function that was called was in the process
    of being converted for tracing and had a breakpoint on it. The idea is,
    before calling the lockdep code, do a load_idt() to the special IDT that
    kept the breakpoint stack from reseting. This worked well as a quick fix
    for this kernel release, until a certain config caused a lockup in the
    function tracer start up tests.
    
    Investigating it, I found that the load_idt that was used to prevent
    the int3 from changing stacks was itself being traced!
    
    Even though the config had CONFIG_OPTIMIZE_INLINING disabled, and
    all 'inline' tags were set to always inline, there were still cases that
    it did not inline! This was caused by CONFIG_PARAVIRT_GUEST, where it
    would add a pointer to the native_load_idt() which made that function
    to be traced.
    
    Commit 45959ee7aa645815a ("ftrace: Do not function trace inlined functions")
    only touched the 'inline' tags when CONFIG_OPMITIZE_INLINING was enabled.
    PARAVIRT_GUEST shows that this was not enough and we need to also
    mark always_inline with notrace as well.
    
    Reported-by: Fengguang Wu <wfg@linux.intel.com>
    Tested-by: Fengguang Wu <wfg@linux.intel.com>
    Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index e5834aa..6a6d7ae 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -47,9 +47,9 @@
  */
 #if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \
     !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4)
-# define inline		inline		__attribute__((always_inline))
-# define __inline__	__inline__	__attribute__((always_inline))
-# define __inline	__inline	__attribute__((always_inline))
+# define inline		inline		__attribute__((always_inline)) notrace
+# define __inline__	__inline__	__attribute__((always_inline)) notrace
+# define __inline	__inline	__attribute__((always_inline)) notrace
 #else
 /* A lot of inline functions can cause havoc with function tracing */
 # define inline		inline		notrace