Messages in this thread | | | Date | Tue, 24 Oct 2023 13:55:44 +0300 | From | Andy Shevchenko <> | Subject | Re: [PATCH v3 1/1] clk: divider: Fix divisor masking on 64 bit platforms |
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On Mon, Oct 23, 2023 at 08:34:12PM -0700, Stephen Boyd wrote: > Quoting Sebastian Reichel (2023-06-30 11:38:35)
> > --- a/include/linux/math.h > > +++ b/include/linux/math.h > > @@ -36,6 +36,17 @@ > > > > #define DIV_ROUND_UP __KERNEL_DIV_ROUND_UP > > > > +/** > > + * DIV_ROUND_UP_NO_OVERFLOW - divide two numbers and always round up > > + * @n: numerator / dividend > > + * @d: denominator / divisor > > + * > > + * This functions does the same as DIV_ROUND_UP, but internally uses a > > + * division and a modulo operation instead of math tricks. This way it > > + * avoids overflowing when handling big numbers. > > + */ > > +#define DIV_ROUND_UP_NO_OVERFLOW(n, d) (((n) / (d)) + !!((n) % (d))) > > Can you get someone to review/ack this macro? Maybe Andy? > > > + > > #define DIV_ROUND_DOWN_ULL(ll, d) \ > > ({ unsigned long long _tmp = (ll); do_div(_tmp, d); _tmp; })
First of all, it should be a separate patch and second, same issue is being discussed here (as it needs to be fixed in UAPI header directly):
https://lore.kernel.org/all/your-ad-here.call-01697881440-ext-2458@work.hours/
-- With Best Regards, Andy Shevchenko
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