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Subjectdo_div vs sector_t

# define do_div(n,base) ({ \
uint32_t __base = (base); \
uint32_t __rem; \
if (likely(((n) >> 32) == 0)) { \

so if we call do_div() on a u32, the compiler emits nasal daemons.
and we do this -- in the antcipatory scheduler:

if (aic->seek_samples) {
aic->seek_mean = aic->seek_total + 128;
do_div(aic->seek_mean, aic->seek_samples);
}

seek_mean is a sector_t so sometimes it's 64-bit on a 32-bit platform.
so we can't avoid calling do_div().

This almost works (the warning is harmless since gcc optimises away the call)

# define do_div(n,base) ({ \
uint32_t __base = (base); \
uint32_t __rem; \
if ((sizeof(n) < 8) || (likely(((n) >> 32) == 0))) { \
__rem = (uint32_t)(n) % __base; \
(n) = (uint32_t)(n) / __base; \
} else \
__rem = __div64_32(&(n), __base); \
__rem; \
})

Better ideas?

--
"It's not Hollywood. War is real, war is primarily not about defeat or
victory, it is about death. I've seen thousands and thousands of dead bodies.
Do you think I want to have an academic debate on this subject?" -- Robert Fisk
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