tracing: branch tracer, fix vdso crash

Impact: fix bootup crash

the branch tracer missed arch/x86/vdso/vclock_gettime.c from
disabling tracing, which caused such bootup crashes:

  [  201.840097] init[1]: segfault at 7fffed3fe7c0 ip 00007fffed3fea2e sp 000077

also clean up the ugly ifdefs in arch/x86/kernel/vsyscall_64.c by
creating DISABLE_UNLIKELY_PROFILE facility for code to turn off
instrumentation on a per file basis.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/x86/vdso/vclock_gettime.c b/arch/x86/vdso/vclock_gettime.c
index 1ef0f90813d6..6e667631e7dc 100644
--- a/arch/x86/vdso/vclock_gettime.c
+++ b/arch/x86/vdso/vclock_gettime.c
@@ -9,6 +9,9 @@
  * Also alternative() doesn't work.
  */
 
+/* Disable profiling for userspace code: */
+#define DISABLE_UNLIKELY_PROFILE
+
 #include <linux/kernel.h>
 #include <linux/posix-timers.h>
 #include <linux/time.h>