Re: [RFC 01/32] fs: introduce new 'struct inode_time'

Geert Uytterhoeven
2014-05-31T07:56:32Z

Hi Arnd,

On Fri, May 30, 2014 at 10:01 PM, Arnd Bergmann <arnd@arndb.de> wrote:
> + * The variant using bit fields is less efficient to access, but
> + * small and has a wider range as the 32-bit one, plus it keeps
> + * the signedness of the original timespec.
> + */
> +struct inode_time {
> + long long tv_sec : 34;
> + int tv_nsec : 30;
> +};

Don't you need 31 bits for tv_nsec, to accommodate for the sign bit?
I know you won't really store negative numbers there, but storing a large
positive number will become negative on read out, won't it?

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

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