53 u32 __get_random_u32_below(u32 ceil);
56  * Returns a random integer in the interval [0, ceil), with uniform
57  * distribution, suitable for all uses. Fastest when ceil is a constant, but
58  * still fast for variable ceil as well.
60 static inline u32 get_random_u32_below(u32 ceil)  in get_random_u32_below()  argument
62 	if (!__builtin_constant_p(ceil))  in get_random_u32_below()
63 		return __get_random_u32_below(ceil);  in get_random_u32_below()
66 	 * For the fast path, below, all operations on ceil are precomputed by  in get_random_u32_below()
71 	 * whose lower half would indicate a range indivisible by ceil.  in get_random_u32_below()
73 	BUILD_BUG_ON_MSG(!ceil, "get_random_u32_below() must take ceil > 0");  in get_random_u32_below()
74 	if (ceil <= 1)  in get_random_u32_below()
77 		if (ceil <= 1U << 8) {  in get_random_u32_below()
78 			u32 mult = ceil * get_random_u8();  in get_random_u32_below()
79 			if (likely(is_power_of_2(ceil) || (u8)mult >= (1U << 8) % ceil))  in get_random_u32_below()
81 		} else if (ceil <= 1U << 16) {  in get_random_u32_below()
82 			u32 mult = ceil * get_random_u16();  in get_random_u32_below()
83 			if (likely(is_power_of_2(ceil) || (u16)mult >= (1U << 16) % ceil))  in get_random_u32_below()
86 			u64 mult = (u64)ceil * get_random_u32();  in get_random_u32_below()
87 			if (likely(is_power_of_2(ceil) || (u32)mult >= -ceil % ceil))  in get_random_u32_below()
106  * Returns a random integer in the interval [floor, ceil], with uniform
107  * distribution, suitable for all uses. Fastest when floor and ceil are
108  * constant, but still fast for variable floor and ceil as well.
110 static inline u32 get_random_u32_inclusive(u32 floor, u32 ceil)  in get_random_u32_inclusive()  argument
112 	BUILD_BUG_ON_MSG(__builtin_constant_p(floor) && __builtin_constant_p(ceil) &&  in get_random_u32_inclusive()
113 			 (floor > ceil || ceil - floor == U32_MAX),  in get_random_u32_inclusive()
114 			 "get_random_u32_inclusive() must take floor <= ceil");  in get_random_u32_inclusive()
115 	return floor + get_random_u32_below(ceil - floor + 1);  in get_random_u32_inclusive()