Re: [PATCH 5/7 v6] trace, RAS: Add eMCA trace event interface

[Steven Rostedt <rostedt@goodmis.org>]

On Tue, 3 Jun 2014 10:35:44 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:


> I'll still need to add that __get_dynamic_array_len() helper. I'll send
> you something tonight.
> 

I got caught up in other work, but I wrote it this morning and I'm
adding it to my 3.16 queue. Thus, you can use this:

-- Steve

>From beba4bb096201ceec0e8cfb7ce3172a53015bdaf Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (Red Hat)" <rostedt@goodmis.org>
Date: Wed, 4 Jun 2014 14:29:33 -0400
Subject: [PATCH] tracing: Add __get_dynamic_array_len() macro for trace events

If a trace event uses a dynamic array for something other than a string
then there's currently no way the TP_printk() can figure out what size
it is. A __get_dynamic_array_len() is required to know the length.

This also simplifies the __get_bitmask() macro which required it as well,
but instead just hardcoded it.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/trace/ftrace.h | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 9b7a989..0fd06fe 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -203,6 +203,10 @@
 #define __get_dynamic_array(field)	\
 		((void *)__entry + (__entry->__data_loc_##field & 0xffff))
 
+#undef __get_dynamic_array_len
+#define __get_dynamic_array_len(field)	\
+		((__entry->__data_loc_##field >> 16) & 0xffff)
+
 #undef __get_str
 #define __get_str(field) (char *)__get_dynamic_array(field)
 
@@ -211,7 +215,7 @@
 	({								\
 		void *__bitmask = __get_dynamic_array(field);		\
 		unsigned int __bitmask_size;				\
-		__bitmask_size = (__entry->__data_loc_##field >> 16) & 0xffff; \
+		__bitmask_size = __get_dynamic_array_len(field);	\
 		ftrace_print_bitmask_seq(p, __bitmask, __bitmask_size);	\
 	})
 
@@ -636,6 +640,7 @@ static inline void ftrace_test_probe_##call(void)			\
 #undef __print_symbolic
 #undef __print_hex
 #undef __get_dynamic_array
+#undef __get_dynamic_array_len
 #undef __get_str
 #undef __get_bitmask
 
@@ -700,6 +705,10 @@ __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
 #define __get_dynamic_array(field)	\
 		((void *)__entry + (__entry->__data_loc_##field & 0xffff))
 
+#undef __get_dynamic_array_len
+#define __get_dynamic_array_len(field)	\
+		((__entry->__data_loc_##field >> 16) & 0xffff)
+
 #undef __get_str
 #define __get_str(field) (char *)__get_dynamic_array(field)
 
-- 
1.8.1.4