5cca7619a5
move div_long_long_rem() from jiffies.h into a new calc64.h include file, as it is a general math function useful for other things than the jiffy code. Convert it to an inline function Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
50 lines
1.3 KiB
C
50 lines
1.3 KiB
C
#ifndef _LINUX_CALC64_H
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#define _LINUX_CALC64_H
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#include <linux/types.h>
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#include <asm/div64.h>
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/*
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* This is a generic macro which is used when the architecture
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* specific div64.h does not provide a optimized one.
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*
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* The 64bit dividend is divided by the divisor (data type long), the
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* result is returned and the remainder stored in the variable
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* referenced by remainder (data type long *). In contrast to the
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* do_div macro the dividend is kept intact.
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*/
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#ifndef div_long_long_rem
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#define div_long_long_rem(dividend, divisor, remainder) \
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do_div_llr((dividend), divisor, remainder)
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static inline unsigned long do_div_llr(const long long dividend,
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const long divisor, long *remainder)
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{
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u64 result = dividend;
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*(remainder) = do_div(result, divisor);
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return (unsigned long) result;
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}
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#endif
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/*
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* Sign aware variation of the above. On some architectures a
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* negative dividend leads to an divide overflow exception, which
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* is avoided by the sign check.
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*/
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static inline long div_long_long_rem_signed(const long long dividend,
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const long divisor, long *remainder)
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{
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long res;
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if (unlikely(dividend < 0)) {
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res = -div_long_long_rem(-dividend, divisor, remainder);
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*remainder = -(*remainder);
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} else
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res = div_long_long_rem(dividend, divisor, remainder);
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return res;
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}
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#endif
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