Re: [PATCH v2] clocksource: Use GENMASK_ULL in definition of CLOCKSOURCE_MASK

From: Thomas Gleixner
Date: Tue Apr 18 2017 - 04:16:55 EST


On Mon, 17 Apr 2017, Matthias Kaehlcke wrote:
> Besides reusing existing code this removes the special case handling
> for 64-bit masks, which causes clang to raise a shift count overflow
> warning due to https://bugs.llvm.org//show_bug.cgi?id=10030.
>
> Suggested-by: Dmitry Torokhov <dtor@xxxxxxxxxxxx>
> Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> ---
> Changes in v2:
> - Remove unnecessary cast to u64
>
> include/linux/clocksource.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
> index cfc75848a35d..f2b10d9ebd04 100644
> --- a/include/linux/clocksource.h
> +++ b/include/linux/clocksource.h
> @@ -120,7 +120,7 @@ struct clocksource {
> #define CLOCK_SOURCE_RESELECT 0x100
>
> /* simplify initialization of mask field */
> -#define CLOCKSOURCE_MASK(bits) (u64)((bits) < 64 ? ((1ULL<<(bits))-1) : -1)
> +#define CLOCKSOURCE_MASK(bits) GENMASK_ULL((bits) - 1, 0)
>
> static inline u32 clocksource_freq2mult(u32 freq, u32 shift_constant, u64 from)
> {
> --
> 2.12.2.762.g0e3151a226-goog

Neither patch nor git-am can apply that patch. Please fix your tools.

Thanks,

tglx