diff options
| author | Steven Rostedt <rostedt@goodmis.org> | 2012-06-14 10:54:28 -0400 |
|---|---|---|
| committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2016-09-29 06:49:03 +0200 |
| commit | 00f9406cb4d5ea9adacf37616cd2283384228c82 (patch) | |
| tree | d7d8de044c89d0b76544b17528f01aa09c47378a | |
| parent | 04a62f449318df28ba24cabeed6fab389f3a70ec (diff) | |
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>
(cherry picked from commit 93b3cca1ccd30b1ad290951a3fc7c10c73db7313)
| -rw-r--r-- | include/linux/compiler-gcc.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 3fd17c249221..4c1430bc8e24 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 |