tracing: Add __field_struct macro for TRACE_EVENT()
Currently the __field() macro in TRACE_EVENT is only good for primitive
values, such as integers and pointers, but it fails on complex data types
such as structures or unions. This is because the __field() macro
determines if the variable is signed or not with the test of:
(((type)(-1)) < (type)1)
Unfortunately, that fails when type is a structure.
Since trace events should support structures as fields a new macro
is created for such a case called __field_struct() which acts exactly
the same as __field() does but it does not do the signed type check
and just uses a constant false for that answer.
Cc: Tony Luck <tony.luck@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 0fd06fe..26b4f2e 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -44,6 +44,12 @@
#undef __field_ext
#define __field_ext(type, item, filter_type) type item;
+#undef __field_struct
+#define __field_struct(type, item) type item;
+
+#undef __field_struct_ext
+#define __field_struct_ext(type, item, filter_type) type item;
+
#undef __array
#define __array(type, item, len) type item[len];
@@ -122,6 +128,12 @@
#undef __field_ext
#define __field_ext(type, item, filter_type)
+#undef __field_struct
+#define __field_struct(type, item)
+
+#undef __field_struct_ext
+#define __field_struct_ext(type, item, filter_type)
+
#undef __array
#define __array(type, item, len)
@@ -315,9 +327,21 @@
if (ret) \
return ret;
+#undef __field_struct_ext
+#define __field_struct_ext(type, item, filter_type) \
+ ret = trace_define_field(event_call, #type, #item, \
+ offsetof(typeof(field), item), \
+ sizeof(field.item), \
+ 0, filter_type); \
+ if (ret) \
+ return ret;
+
#undef __field
#define __field(type, item) __field_ext(type, item, FILTER_OTHER)
+#undef __field_struct
+#define __field_struct(type, item) __field_struct_ext(type, item, FILTER_OTHER)
+
#undef __array
#define __array(type, item, len) \
do { \
@@ -379,6 +403,12 @@
#undef __field_ext
#define __field_ext(type, item, filter_type)
+#undef __field_struct
+#define __field_struct(type, item)
+
+#undef __field_struct_ext
+#define __field_struct_ext(type, item, filter_type)
+
#undef __array
#define __array(type, item, len)
@@ -550,6 +580,9 @@
#undef __field
#define __field(type, item)
+#undef __field_struct
+#define __field_struct(type, item)
+
#undef __array
#define __array(type, item, len)