kernel_optimize_test/include/vdso/math64.h
Vincenzo Frascino b874b8358c linux/math64.h: Extract common header for vDSO
The vDSO library should only include the necessary headers required for
a userspace library (UAPI and a minimal set of kernel headers). To make
this possible it is necessary to isolate from the kernel headers the
common parts that are strictly necessary to build the library.

Split math64.h into linux and common headers to make the latter suitable
for inclusion in the vDSO library.

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200320145351.32292-10-vincenzo.frascino@arm.com
2020-03-21 15:23:56 +01:00

25 lines
468 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __VDSO_MATH64_H
#define __VDSO_MATH64_H
static __always_inline u32
__iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
{
u32 ret = 0;
while (dividend >= divisor) {
/* The following asm() prevents the compiler from
optimising this loop into a modulo operation. */
asm("" : "+rm"(dividend));
dividend -= divisor;
ret++;
}
*remainder = dividend;
return ret;
}
#endif /* __VDSO_MATH64_H */