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Subject[PATCH 1/2] [PATCH 1/2] Introduce new macros min_lt and max_lt for comparing with larger type
A useful use case for min_t and max_t is comparing two values with larger
type. For example comparing an u64 and an u32, usually we do not want to
truncate the u64, so we need use min_t or max_t with u64.

To simplify the usage introducing two more macros min_lt and max_lt,
'lt' means larger type.

Signed-off-by: Dave Young <dyoung@redhat.com>
---
include/linux/kernel.h | 13 +++++++++++++
1 file changed, 13 insertions(+)

--- linux.orig/include/linux/kernel.h
+++ linux/include/linux/kernel.h
@@ -798,6 +798,19 @@ static inline void ftrace_dump(enum ftra
type __max2 = (y); \
__max1 > __max2 ? __max1: __max2; })

+/*
+ * use type of larger size in min_lt and max_lt
+ */
+#define min_lt(x, y) ({ \
+ int sx = sizeof(typeof(x)); \
+ int sy = sizeof(typeof(y)); \
+ sx > sy ? min_t(typeof(x), x, y) : min_t(typeof(y), x, y); })
+
+#define max_lt(x, y) ({ \
+ int sx = sizeof(typeof(x)); \
+ int sy = sizeof(typeof(y)); \
+ sx > sy ? max_t(typeof(x), x, y) : max_t(typeof(y), x, y); })
+
/**
* clamp_t - return a value clamped to a given range using a given type
* @type: the type of variable to use

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