diff options
| -rw-r--r-- | include/linux/math64.h | 19 | ||||
| -rw-r--r-- | lib/div64.c | 15 |
2 files changed, 20 insertions, 14 deletions
diff --git a/include/linux/math64.h b/include/linux/math64.h index 177785e1e4a3..c87f1528703a 100644 --- a/include/linux/math64.h +++ b/include/linux/math64.h | |||
| @@ -83,4 +83,23 @@ static inline s64 div_s64(s64 dividend, s32 divisor) | |||
| 83 | 83 | ||
| 84 | u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder); | 84 | u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder); |
| 85 | 85 | ||
| 86 | static __always_inline u32 | ||
| 87 | __iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder) | ||
| 88 | { | ||
| 89 | u32 ret = 0; | ||
| 90 | |||
| 91 | while (dividend >= divisor) { | ||
| 92 | /* The following asm() prevents the compiler from | ||
| 93 | optimising this loop into a modulo operation. */ | ||
| 94 | asm("" : "+rm"(dividend)); | ||
| 95 | |||
| 96 | dividend -= divisor; | ||
| 97 | ret++; | ||
| 98 | } | ||
| 99 | |||
| 100 | *remainder = dividend; | ||
| 101 | |||
| 102 | return ret; | ||
| 103 | } | ||
| 104 | |||
| 86 | #endif /* _LINUX_MATH64_H */ | 105 | #endif /* _LINUX_MATH64_H */ |
diff --git a/lib/div64.c b/lib/div64.c index 76c01542d3e1..a111eb8de9cf 100644 --- a/lib/div64.c +++ b/lib/div64.c | |||
| @@ -105,19 +105,6 @@ EXPORT_SYMBOL(div64_u64); | |||
| 105 | */ | 105 | */ |
| 106 | u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder) | 106 | u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder) |
| 107 | { | 107 | { |
| 108 | u32 ret = 0; | 108 | return __iter_div_u64_rem(dividend, divisor, remainder); |
| 109 | |||
| 110 | while (dividend >= divisor) { | ||
| 111 | /* The following asm() prevents the compiler from | ||
| 112 | optimising this loop into a modulo operation. */ | ||
| 113 | asm("" : "+rm"(dividend)); | ||
| 114 | |||
| 115 | dividend -= divisor; | ||
| 116 | ret++; | ||
| 117 | } | ||
| 118 | |||
| 119 | *remainder = dividend; | ||
| 120 | |||
| 121 | return ret; | ||
| 122 | } | 109 | } |
| 123 | EXPORT_SYMBOL(iter_div_u64_rem); | 110 | EXPORT_SYMBOL(iter_div_u64_rem); |
