kcsan: Add docbook header for data_race()

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>

include/linux/compiler.h

@@ -315,13 +315,15 @@ unsigned long read_word_at_a_time(const void *addr)
 
 #include <linux/kcsan.h>
 
-/*
- * data_race(): macro to document that accesses in an expression may conflict with
- * other concurrent accesses resulting in data races, but the resulting
- * behaviour is deemed safe regardless.
+/**
+ * data_race - mark an expression as containing intentional data races
+ *
+ * This data_race() macro is useful for situations in which data races
+ * should be forgiven.  One example is diagnostic code that accesses
+ * shared variables but is not a part of the core synchronization design.
  *
- * This macro *does not* affect normal code generation, but is a hint to tooling
- * that data races here should be ignored.
+ * This macro *does not* affect normal code generation, but is a hint
+ * to tooling that data races here are to be ignored.
  */
 #define data_race(expr)                                                        \
 	({                                                                     \