[PATCH v9 21/32] dyndbg: change __dynamic_func_call_cls* macros into expressions

[Jim Cromie <jim.cromie@gmail.com>]

The Xe driver's XE_IOCTL_DBG macro calls drm_dbg() from inside an if
(expression).  This breaks when CONFIG_DRM_USE_DYNAMIC_DEBUG=y because
the invoked macro has a do-while-0 wrapper, and is not an expression.

   if (cond && (drm_dbg("expr-form"),1)) {
      ... do some more stuff
   }

Fix for this usage by changing __dynamic_func_call_cls{,_no_desc}
macros into expressions, by replacing the do-while-0s with a ({ })
wrapper.  In the common usage, the trailing ';' converts the
expression into a statement.

   drm_dbg("statement form");

Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
---
 include/linux/dynamic_debug.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/linux/dynamic_debug.h b/include/linux/dynamic_debug.h
index b6198ecc854d..80160028461a 100644
--- a/include/linux/dynamic_debug.h
+++ b/include/linux/dynamic_debug.h
@@ -224,24 +224,24 @@ void __dynamic_ibdev_dbg(struct _ddebug *descriptor,
  * (|_cls):	adds in _DPRINT_CLASS_DFLT as needed
  * (|_no_desc):	former gets callsite descriptor as 1st arg (for prdbgs)
  */
-#define __dynamic_func_call_cls(id, cls, fmt, func, ...) do {	\
+#define __dynamic_func_call_cls(id, cls, fmt, func, ...) ({	\
 	DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt);	\
 	if (DYNAMIC_DEBUG_BRANCH(id)) {				\
 		func(&id, ##__VA_ARGS__);			\
 		__dynamic_dump_stack(id);			\
 	}							\
-} while (0)
+})
 #define __dynamic_func_call(id, fmt, func, ...)				\
 	__dynamic_func_call_cls(id, _DPRINTK_CLASS_DFLT, fmt,		\
 				func, ##__VA_ARGS__)
 
-#define __dynamic_func_call_cls_no_desc(id, cls, fmt, func, ...) do {	\
+#define __dynamic_func_call_cls_no_desc(id, cls, fmt, func, ...) ({	\
 	DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt);		\
 	if (DYNAMIC_DEBUG_BRANCH(id)) {					\
 		func(__VA_ARGS__);					\
 		__dynamic_dump_stack(id);				\
 	}								\
-} while (0)
+})
 #define __dynamic_func_call_no_desc(id, fmt, func, ...)			\
 	__dynamic_func_call_cls_no_desc(id, _DPRINTK_CLASS_DFLT,	\
 					fmt, func, ##__VA_ARGS__)
-- 
2.52.0