kernel.h: add {min,max}3 macros
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.
[akpm@linux-foundation.org: fix warnings]
Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
Cc: Joe Perches <joe@perches.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index edef168..8e786a2 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -651,6 +651,24 @@
(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); \
+ (void) (&_min1 == &_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); \
+ (void) (&_max1 == &_max3); \
+ _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
+ (_max2 > _max3 ? _max2 : _max3); })
+
/**
* min_not_zero - return the minimum that is _not_ zero, unless both are zero
* @x: value1