diff options
author | Stephen Hemminger <shemminger@linux-foundation.org> | 2007-03-22 15:10:18 -0400 |
---|---|---|
committer | David S. Miller <davem@sunset.davemloft.net> | 2007-04-26 01:27:18 -0400 |
commit | 22b9a0a3a49ab1a856e0853b3f3dd2abd156bd7c (patch) | |
tree | bacdd0f5ab3e94f5f137b03072b2319eeb767d2b /lib | |
parent | c454673da7c1d6533f40ec2f788023df9af56ebf (diff) |
[LIB]: div64_64 optimization
Minor optimization of div64_64. do_div() already does optimization
for the case of 32 by 32 divide, so no need to do it here.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/div64.c | 16 |
1 files changed, 7 insertions, 9 deletions
diff --git a/lib/div64.c b/lib/div64.c index c3d7655cdfb5..74f0c8cb4031 100644 --- a/lib/div64.c +++ b/lib/div64.c | |||
@@ -61,20 +61,18 @@ EXPORT_SYMBOL(__div64_32); | |||
61 | /* 64bit divisor, dividend and result. dynamic precision */ | 61 | /* 64bit divisor, dividend and result. dynamic precision */ |
62 | uint64_t div64_64(uint64_t dividend, uint64_t divisor) | 62 | uint64_t div64_64(uint64_t dividend, uint64_t divisor) |
63 | { | 63 | { |
64 | uint32_t d = divisor; | 64 | uint32_t high, d; |
65 | 65 | ||
66 | if (divisor > 0xffffffffULL) { | 66 | high = divisor >> 32; |
67 | unsigned int shift = fls(divisor >> 32); | 67 | if (high) { |
68 | unsigned int shift = fls(high); | ||
68 | 69 | ||
69 | d = divisor >> shift; | 70 | d = divisor >> shift; |
70 | dividend >>= shift; | 71 | dividend >>= shift; |
71 | } | 72 | } else |
73 | d = divisor; | ||
72 | 74 | ||
73 | /* avoid 64 bit division if possible */ | 75 | do_div(dividend, d); |
74 | if (dividend >> 32) | ||
75 | do_div(dividend, d); | ||
76 | else | ||
77 | dividend = (uint32_t) dividend / d; | ||
78 | 76 | ||
79 | return dividend; | 77 | return dividend; |
80 | } | 78 | } |