[PATCH 1/2] kernel.h: add {min,max}3 macros

[Hagen Paul Pfeifer]

Introduce two additional min/max macros to compare three operands.
This will save some cycles as well as some bytes on the stack and last
but not least more pleasing as macro nesting.

Signed-off-by: Hagen Paul Pfeifer <hagen@xxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Joe Perches <joe@xxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
---
 include/linux/kernel.h |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 2b0a35e..9a9b52c 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -640,6 +640,22 @@ static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
 	(void) (&_max1 == &_max2);		\
 	_max1 > _max2 ? _max1 : _max2; })
 
+#define min3(x, y, z) ({			\
+	typeof(x) _min1 = (x);			\
+	typeof(y) _min2 = (y);			\
+	typeof(z) _min3 = (z);			\
+	(void) (&_min1 == &_min2 == &_min3);	\
+	_min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
+		(_min2 < _min3 ? _min2 : _min3); })
+
+#define max3(x, y, z) ({			\
+	typeof(x) _max1 = (x);			\
+	typeof(y) _max2 = (y);			\
+	typeof(z) _max3 = (z);			\
+	(void) (&_max1 == &_max2 == &_max3);	\
+	_max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
+		(_max2 > _max3 ? _max2 : _max3); })
+
 /**
  * clamp - return a value clamped to a given range with strict typechecking
  * @val: current value
-- 
1.7.2.1.95.g3d045.dirty

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/