Patch "tracing: Fix tick_stop tracepoint symbols for user export" has been added to the 4.7-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    tracing: Fix tick_stop tracepoint symbols for user export

to the 4.7-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     tracing-fix-tick_stop-tracepoint-symbols-for-user-export.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From c87edb36118664f1fa275107c1138b6f47793240 Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Date: Fri, 5 Aug 2016 12:41:52 -0400
Subject: tracing: Fix tick_stop tracepoint symbols for user export

From: Steven Rostedt (Red Hat) <rostedt@goodmis.org>

commit c87edb36118664f1fa275107c1138b6f47793240 upstream.

The symbols used in the tick_stop tracepoint were not being converted
properly into integers in the trace_stop format file. Instead we had this:

print fmt: "success=%d dependency=%s", REC->success,
    __print_symbolic(REC->dependency, { 0, "NONE" },
     { (1 << TICK_DEP_BIT_POSIX_TIMER), "POSIX_TIMER" },
     { (1 << TICK_DEP_BIT_PERF_EVENTS), "PERF_EVENTS" },
     { (1 << TICK_DEP_BIT_SCHED), "SCHED" },
     { (1 << TICK_DEP_BIT_CLOCK_UNSTABLE), "CLOCK_UNSTABLE" })

User space tools have no idea how to parse "TICK_DEP_BIT_SCHED" or the other
symbols used to do the bit shifting. The reason is that the conversion was
done with using the TICK_DEP_MASK_* symbols which are just macros that
convert to the BIT shift itself (with the exception of NONE, which was
converted properly, because it doesn't use bits, and is defined as zero).

The TICK_DEP_BIT_* needs to be denoted by TRACE_DEFINE_ENUM() in order to
have this properly converted for user space tools to parse this event.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Fixes: e6e6cc22e067 ("nohz: Use enum code for tick stop failure tracing message")
Reported-by: Luiz Capitulino <lcapitulino@redhat.com>
Tested-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 include/trace/events/timer.h |   14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

--- a/include/trace/events/timer.h
+++ b/include/trace/events/timer.h
@@ -330,24 +330,32 @@ TRACE_EVENT(itimer_expire,
 #ifdef CONFIG_NO_HZ_COMMON
 
 #define TICK_DEP_NAMES					\
-		tick_dep_name(NONE)			\
+		tick_dep_mask_name(NONE)		\
 		tick_dep_name(POSIX_TIMER)		\
 		tick_dep_name(PERF_EVENTS)		\
 		tick_dep_name(SCHED)			\
 		tick_dep_name_end(CLOCK_UNSTABLE)
 
 #undef tick_dep_name
+#undef tick_dep_mask_name
 #undef tick_dep_name_end
 
-#define tick_dep_name(sdep) TRACE_DEFINE_ENUM(TICK_DEP_MASK_##sdep);
-#define tick_dep_name_end(sdep)  TRACE_DEFINE_ENUM(TICK_DEP_MASK_##sdep);
+/* The MASK will convert to their bits and they need to be processed too */
+#define tick_dep_name(sdep) TRACE_DEFINE_ENUM(TICK_DEP_BIT_##sdep); \
+	TRACE_DEFINE_ENUM(TICK_DEP_MASK_##sdep);
+#define tick_dep_name_end(sdep)  TRACE_DEFINE_ENUM(TICK_DEP_BIT_##sdep); \
+	TRACE_DEFINE_ENUM(TICK_DEP_MASK_##sdep);
+/* NONE only has a mask defined for it */
+#define tick_dep_mask_name(sdep) TRACE_DEFINE_ENUM(TICK_DEP_MASK_##sdep);
 
 TICK_DEP_NAMES
 
 #undef tick_dep_name
+#undef tick_dep_mask_name
 #undef tick_dep_name_end
 
 #define tick_dep_name(sdep) { TICK_DEP_MASK_##sdep, #sdep },
+#define tick_dep_mask_name(sdep) { TICK_DEP_MASK_##sdep, #sdep },
 #define tick_dep_name_end(sdep) { TICK_DEP_MASK_##sdep, #sdep }
 
 #define show_tick_dep_name(val)				\


Patches currently in stable-queue which might be from rostedt@goodmis.org are

queue-4.7/tracing-fix-tick_stop-tracepoint-symbols-for-user-export.patch