Re: [PATCH net-next 1/4] time64.h: define PSEC_PER_NSEC and use it in tc-taprio

[Vincenzo Frascino]

Hi Vladimir,

On 6/26/22 13:05, Vladimir Oltean wrote:
> Time-sensitive networking code needs to work with PTP times expressed in
> nanoseconds, and with packet transmission times expressed in
> picoseconds, since those would be fractional at higher than gigabit
> speed when expressed in nanoseconds.
> 
> Convert the existing uses in tc-taprio to a PSEC_PER_NSEC macro.
> 
> Cc: Andy Lutomirski <luto@xxxxxxxxxx>
> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
> Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
> ---
>  include/vdso/time64.h  | 1 +
>  net/sched/sch_taprio.c | 4 ++--
>  2 files changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/include/vdso/time64.h b/include/vdso/time64.h
> index b40cfa2aa33c..f1c2d02474ae 100644
> --- a/include/vdso/time64.h
> +++ b/include/vdso/time64.h
> @@ -6,6 +6,7 @@
>  #define MSEC_PER_SEC	1000L
>  #define USEC_PER_MSEC	1000L
>  #define NSEC_PER_USEC	1000L
> +#define PSEC_PER_NSEC	1000L

Are you planning to use this definition in the vdso library code? If not, you
should define PSEC_PER_NSEC in "include/linux/time64.h". The vdso namespace
should contain only the definitions shared by the implementations of the kernel
and of the vdso library.

...
-- 
Regards,
Vincenzo