From 4d4c9cc839a308be3289a361ccba4447ee140552 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Tue, 17 Jun 2014 08:59:16 -0400 Subject: [PATCH] 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 Signed-off-by: Steven Rostedt --- include/trace/ftrace.h | 33 ++++++++++++++++++++++ samples/trace_events/trace-events-sample.h | 3 +- 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 0fd06fef9fac..26b4f2e13275 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 @@ static struct trace_event_functions ftrace_event_type_funcs_##call = { \ 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 @@ ftrace_define_fields_##call(struct ftrace_event_call *event_call) \ #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 @@ static inline notrace int ftrace_get_offsets_##call( \ #undef __field #define __field(type, item) +#undef __field_struct +#define __field_struct(type, item) + #undef __array #define __array(type, item, len) diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h index 6af373236d73..4b0113f73ee9 100644 --- a/samples/trace_events/trace-events-sample.h +++ b/samples/trace_events/trace-events-sample.h @@ -56,7 +56,8 @@ * struct: This defines the way the data will be stored in the ring buffer. * There are currently two types of elements. __field and __array. * a __field is broken up into (type, name). Where type can be any - * type but an array. + * primitive type (integer, long or pointer). __field_struct() can + * be any static complex data value (struct, union, but not an array). * For an array. there are three fields. (type, name, size). The * type of elements in the array, the name of the field and the size * of the array. -- GitLab