diff options
authorSteven Rostedt <srostedt@redhat.com>2009-03-26 11:43:36 -0400
committerSteven Rostedt <rostedt@goodmis.org>2009-04-23 23:03:56 -0400
commit75db37d2f4c0ad9466ead57d467277d097b4105c (patch)
parent89ec0dee9eba6275d47be0b878cf5f6d5c2fb6eb (diff)
tracing: add size checks for exported ftrace internal structures
The events exported by TRACE_EVENT are automated and are guaranteed to be correct when used. The internal ftrace structures on the other hand are more manually exported. These require the ftrace maintainer to make sure they are up to date. This patch adds a size check to help flag when a type changes in an internal ftrace data structure, and the update needs to be reflected in the export. If a export is incorrect, then the only harm is that the user space tools will not know how to correctly read the internal structures of ftrace. [ Impact: help prevent inconsistent ftrace format print outs ] Signed-off-by: Steven Rostedt <srostedt@redhat.com>
2 files changed, 7 insertions, 0 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 9887131afa03..b92081588088 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -381,8 +381,11 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt,
return cnt;
+extern char *__bad_type_size(void);
#undef FIELD
#define FIELD(type, name) \
+ sizeof(type) != sizeof(field.name) ? __bad_type_size() : \
#type, "common_" #name, offsetof(typeof(field), name), \
diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c
index 48fc02fe73a0..0cb1a142c74f 100644
--- a/kernel/trace/trace_export.c
+++ b/kernel/trace/trace_export.c
@@ -19,8 +19,12 @@
#define TRACE_STRUCT(args...) args
+extern void __bad_type_size(void);
#define TRACE_FIELD(type, item, assign) \
+ if (sizeof(type) != sizeof(field.item)) \
+ __bad_type_size(); \
ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t" \
"offset:%u;\tsize:%u;\n", \
(unsigned int)offsetof(typeof(field), item), \