tools/include: Add _RET_IP_ and math definitions to kernel.h

Add max_t, min_t and clamp functions, together with _RET_IP_
definition, so they can be used in testing.

Signed-off-by: Karolina Drobnik <[e-mail]>
Signed-off-by: Mike Rapoport <[e-mail]>
Link: https://lore.kernel.org/r/230fea3[e-mail]

tools/include/linux/kernel.h

···
 #define UINT_MAX	(~0U)
 #endif
 
+#define _RET_IP_		((unsigned long)__builtin_return_address(0))
+
 #define PERF_ALIGN(x, a)	__PERF_ALIGN_MASK(x, (typeof(x))(a)-1)
 #define __PERF_ALIGN_MASK(x, mask)	(((x)+(mask))&~(mask))
 
···
 	(void) (&_min1 == &_min2);		\
 	_min1 < _min2 ? _min1 : _min2; })
 #endif
+
+#define max_t(type, x, y)	max((type)x, (type)y)
+#define min_t(type, x, y)	min((type)x, (type)y)
+#define clamp(val, lo, hi)	min((typeof(val))max(val, lo), hi)
 
 #ifndef BUG_ON
 #ifdef NDEBUG