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Diffstat (limited to 'arch/x86/kernel/pvclock.c')
-rw-r--r--arch/x86/kernel/pvclock.c41
1 files changed, 2 insertions, 39 deletions
diff --git a/arch/x86/kernel/pvclock.c b/arch/x86/kernel/pvclock.c
index 239427ca02a..008b91eefa1 100644
--- a/arch/x86/kernel/pvclock.c
+++ b/arch/x86/kernel/pvclock.c
@@ -41,48 +41,11 @@ void pvclock_set_flags(u8 flags)
valid_flags = flags;
}
-/*
- * Scale a 64-bit delta by scaling and multiplying by a 32-bit fraction,
- * yielding a 64-bit result.
- */
-static inline u64 scale_delta(u64 delta, u32 mul_frac, int shift)
-{
- u64 product;
-#ifdef __i386__
- u32 tmp1, tmp2;
-#endif
-
- if (shift < 0)
- delta >>= -shift;
- else
- delta <<= shift;
-
-#ifdef __i386__
- __asm__ (
- "mul %5 ; "
- "mov %4,%%eax ; "
- "mov %%edx,%4 ; "
- "mul %5 ; "
- "xor %5,%5 ; "
- "add %4,%%eax ; "
- "adc %5,%%edx ; "
- : "=A" (product), "=r" (tmp1), "=r" (tmp2)
- : "a" ((u32)delta), "1" ((u32)(delta >> 32)), "2" (mul_frac) );
-#elif defined(__x86_64__)
- __asm__ (
- "mul %%rdx ; shrd $32,%%rdx,%%rax"
- : "=a" (product) : "0" (delta), "d" ((u64)mul_frac) );
-#else
-#error implement me!
-#endif
-
- return product;
-}
-
static u64 pvclock_get_nsec_offset(struct pvclock_shadow_time *shadow)
{
u64 delta = native_read_tsc() - shadow->tsc_timestamp;
- return scale_delta(delta, shadow->tsc_to_nsec_mul, shadow->tsc_shift);
+ return pvclock_scale_delta(delta, shadow->tsc_to_nsec_mul,
+ shadow->tsc_shift);
}
/*