Regression: partial revert "tracing: Remove lock_depth from event entry"

This partially reverts commit e6e1e2593592a8f6f6380496655d8c6f67431266.

That commit changed the structure layout of the trace structure, which
in turn broke PowerTOP (1.9x generation) quite badly.

I appreciate not wanting to expose the variable in question, and
PowerTOP was not using it, so I've replaced the variable with just a
padding field - that way if in the future a new field is needed it can
just use this padding field.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index 22b32af1b5e..b5a550a39a7 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -37,6 +37,7 @@ struct trace_entry {
         unsigned char           flags;
         unsigned char           preempt_count;
         int                     pid;
+        int                     padding;
 };
 
 #define FTRACE_MAX_EVENT                                                \