Merge branch 'tip/perf/urgent-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into perf/urgent

1 files changed, 20 insertions, 15 deletions

diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index c6814616653b..97c84a58efb8 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -33,12 +33,7 @@ struct tracepoint {
 	void (*regfunc)(void);
 	void (*unregfunc)(void);
 	struct tracepoint_func __rcu *funcs;
-} __attribute__((aligned(32)));		/*
-					 * Aligned on 32 bytes because it is
-					 * globally visible and gcc happily
-					 * align these on the structure size.
-					 * Keep in sync with vmlinux.lds.h.
-					 */
+};
 
 /*
  * Connect a probe to a tracepoint.
@@ -61,15 +56,15 @@ extern void tracepoint_probe_update_all(void);
 
 struct tracepoint_iter {
 	struct module *module;
-	struct tracepoint *tracepoint;
+	struct tracepoint * const *tracepoint;
 };
 
 extern void tracepoint_iter_start(struct tracepoint_iter *iter);
 extern void tracepoint_iter_next(struct tracepoint_iter *iter);
 extern void tracepoint_iter_stop(struct tracepoint_iter *iter);
 extern void tracepoint_iter_reset(struct tracepoint_iter *iter);
-extern int tracepoint_get_iter_range(struct tracepoint **tracepoint,
-	struct tracepoint *begin, struct tracepoint *end);
+extern int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
+	struct tracepoint * const *begin, struct tracepoint * const *end);
 
 /*
  * tracepoint_synchronize_unregister must be called between the last tracepoint
@@ -84,11 +79,13 @@ static inline void tracepoint_synchronize_unregister(void)
 #define PARAMS(args...) args
 
 #ifdef CONFIG_TRACEPOINTS
-extern void tracepoint_update_probe_range(struct tracepoint *begin,
-	struct tracepoint *end);
+extern
+void tracepoint_update_probe_range(struct tracepoint * const *begin,
+	struct tracepoint * const *end);
 #else
-static inline void tracepoint_update_probe_range(struct tracepoint *begin,
-	struct tracepoint *end)
+static inline
+void tracepoint_update_probe_range(struct tracepoint * const *begin,
+	struct tracepoint * const *end)
 { }
 #endif /* CONFIG_TRACEPOINTS */
 
@@ -174,12 +171,20 @@ do_trace:								\
 	{								\
 	}
 
+/*
+ * We have no guarantee that gcc and the linker won't up-align the tracepoint
+ * structures, so we create an array of pointers that will be used for iteration
+ * on the tracepoints.
+ */
 #define DEFINE_TRACE_FN(name, reg, unreg)				\
 	static const char __tpstrtab_##name[]				\
 	__attribute__((section("__tracepoints_strings"))) = #name;	\
 	struct tracepoint __tracepoint_##name				\
-	__attribute__((section("__tracepoints"), aligned(32))) =	\
-		{ __tpstrtab_##name, 0, reg, unreg, NULL }
+	__attribute__((section("__tracepoints"))) =			\
+		{ __tpstrtab_##name, 0, reg, unreg, NULL };		\
+	static struct tracepoint * const __tracepoint_ptr_##name __used	\
+	__attribute__((section("__tracepoints_ptrs"))) =		\
+		&__tracepoint_##name;
 
 #define DEFINE_TRACE(name)						\
 	DEFINE_TRACE_FN(name, NULL, NULL);