Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
add an inlined version of iter_div_u64_rem
iter_div_u64_rem is used in the x86-64 vdso, which cannot call other
kernel code. For this case, provide the always_inlined version,
__iter_div_u64_rem.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
authored by Jeremy Fitzhardinge and committed by Ingo Molnar d5e181f7 f595ec96
+19
include/linux/math64.h
+19
include/linux/math64.h
···
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u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder);
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static __always_inline u32
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__iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
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{
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u32 ret = 0;
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while (dividend >= divisor) {
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/* The following asm() prevents the compiler from
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optimising this loop into a modulo operation. */
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asm("" : "+rm"(dividend));
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dividend -= divisor;
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ret++;
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}
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*remainder = dividend;
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return ret;
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}
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#endif /* _LINUX_MATH64_H */
+1
-14
lib/div64.c
+1
-14
lib/div64.c
···
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*/
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u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
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{
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u32 ret = 0;
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while (dividend >= divisor) {
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/* The following asm() prevents the compiler from
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optimising this loop into a modulo operation. */
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asm("" : "+rm"(dividend));
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dividend -= divisor;
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ret++;
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}
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*remainder = dividend;
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return ret;
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return __iter_div_u64_rem(dividend, divisor, remainder);
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}
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EXPORT_SYMBOL(iter_div_u64_rem);