Re: [PATCH v2] uapi, posix-timers: provide clockid-related macros and functions to UAPI

From: John Stultz
Date: Tue May 12 2020 - 18:40:23 EST


On Tue, May 12, 2020 at 3:31 PM Eugene Syromiatnikov <esyr@xxxxxxxxxx> wrote:
> On Tue, May 12, 2020 at 10:58:16PM +0300, Sergey Organov wrote:
> > Eugene Syromiatnikov <esyr@xxxxxxxxxx> writes:
> >
> > > As of now, there is no interface exposed for converting pid/fd into
> > > clockid and vice versa; linuxptp, for example, has been carrying these
> > > definitions in missing.h header for quite some time[1].
> > >
> > > [1] https://sourceforge.net/p/linuxptp/code/ci/af380e86/tree/missing.h
> > >
> > > Signed-off-by: Eugene Syromiatnikov <esyr@xxxxxxxxxx>
> > > ---
> > > Changes since v1[1]:
> > > * Actually tried to build with the patch and fixed the build error
> > > reported by kbuild test robot[2].
> > >
> > > [1] https://lkml.org/lkml/2019/9/20/698
> > > [2] https://lkml.org/lkml/2019/9/22/13
> > > ---
> > > include/linux/posix-timers.h | 47 +------------------------------------------
> > > include/uapi/linux/time.h | 48 ++++++++++++++++++++++++++++++++++++++++++++
> > > 2 files changed, 49 insertions(+), 46 deletions(-)
> >
> > Was this patch applied, rejected, lost?
> >
> > I can't find it in the current master.
>
> IIRC, it was ignored.

Overlooked. :) Not intentionally ignored.

I don't have any major objection with adding helpers, though I feel
like you're exporting a lot more to the uapi then applications likely
need.

Would it be better to add just the bits from the missing.h header you
pointed to:
#define CLOCKFD 3
#define FD_TO_CLOCKID(fd) ((~(clockid_t) (fd) << 3) | CLOCKFD)
#define CLOCKID_TO_FD(clk) ((unsigned int) ~((clk) >> 3))

to the uapi header?

thanks
-john