Re: [PATCH v2 4/4] c2y: Add function cnd_timedwait_base and mtx_timedlock_base

[enh <enh@google.com>]

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On Wed, Jun 21, 2023 at 12:08 PM 罗勇刚(Yonggang Luo) <luoyonggang@gmail.com>
wrote:

>
>
> On Thu, Jun 22, 2023 at 3:05 AM enh <enh@google.com> wrote:
> >
> >
> >
> > On Wed, Jun 21, 2023 at 11:39 AM 罗勇刚(Yonggang Luo) <
> luoyonggang@gmail.com> wrote:
> >>
> >>
> >>
> >> On Wed, Jun 21, 2023 at 10:31 PM enh <enh@google.com> wrote:
> >> >
> >> >
> >> >
> >> > On Wed, Jun 21, 2023 at 2:21 AM 罗勇刚(Yonggang Luo) <
> luoyonggang@gmail.com> wrote:
> >> >>
> >> >>
> >> >>
> >> >> On Wed, Jun 21, 2023 at 4:41 AM Joseph Myers <
> joseph@codesourcery.com> wrote:
> >> >> >
> >> >> > On Wed, 21 Jun 2023, Yonggang Luo via Libc-alpha wrote:
> >> >> >
> >> >> > > diff --git a/sysdeps/pthread/threads.h
> b/sysdeps/pthread/threads.h
> >> >> > > index d88d7a3ddd..4f61ad9236 100644
> >> >> > > --- a/sysdeps/pthread/threads.h
> >> >> > > +++ b/sysdeps/pthread/threads.h
> >> >> > > @@ -146,14 +146,22 @@ extern int mtx_lock (mtx_t *__mutex);
> >> >> > >  #ifndef __USE_TIME_BITS64
> >> >> > >  extern int mtx_timedlock (mtx_t *__restrict __mutex,
> >> >> > >                         const struct timespec *__restrict
> __time_point);
> >> >> > > +extern int mtx_timedlock_base (mtx_t *__restrict __mutex, int
> time_base,
> >> >> > > +                               const struct timespec
> *__restrict __time_point);
> >> >> >
> >> >> > As noted, this should be conditional on __USE_GNU.  Since you
> didn't make
> >> >> > it conditional, I'd expect it to have failed the conform/
> namespace tests
> >> >> > - both for the mtx_timedlock_base name itself if there weren't
> incorrect
> >> >> > conform/ changes in the patch series, and for the time_base
> parameter
> >> >> > (parameters in installed headers should always have a leading
> __).  How
> >> >> > did you test these patches?
> >> >>
> >> >> I am not testing these patches yet(as a new contributor for glibc,
> don't know how to do that yet),
> >> >> and for this patch, I'd like to know if the prototype of these two
> functions is proper first
> >> >>
> >> >> int mtx_timedlock_base(mtx_t *restrict m, int time_base, const
> struct timespec *restrict ts);
> >> >>
> >> >> int cnd_timedwait_base(cnd_t *restrict c, mtx_t *restrict m, int
> time_base, const struct timespec *restrict ts);
> >> >>
> >> >> The function name was suggested by Jens Gustedt, and indeed I also
> thought about this name in the first place(because posix has cond_clockwait
> and mutex_clocklock already). And seems enh also like this
> >> >
> >> >
> >> > well, to the extent that i think "pthreads that's also available on
> Windows" is useful to some, sure, i'll continue to add the trivial inline
> functions to bionic so that this is actually portable (
> https://android.googlesource.com/platform/bionic/+/master/libc/include/bits/threads_inlines.h).
> but for Android host tools themselves, i think we'll continue to use
> std::thread or pthreads via mingw.
> >> >
> >> > but my real feedback earlier was the same as what you're seeing here:
> "since this is a WG14-driven thing, it should come as a proposal from there
> first". anyone using bionic or glibc already has perfectly good pthread
> apis, so no real need for this stuff until/unless it's in Windows. (and
> last time i looked, Windows hadn't actually implemented the existing
> <threads.h> stuff yet?)
> >>
> >> Yeah, you are correct, windows msvc doesn't have either pthread or c11
> threads, and pthreads is so huge, so there is multiple third-party c11
> threads implementation for MSVC, that's why I wanna c2y threads comes with
> monotonic mtx_timedlock cnd_timedwait support, so that the third-party c11
> threads implementation have a consistence API to implement.
> >
> >
> > if MS didn't bother to implement the C11 functions, why do you think
> they'd implement any future additions?
>
> I don't bother MS if they will implement the C11 functions, I just want a
> set of cross-platform threads api(c11 threads) to use (non-posix
> non-pthreads), we can always polyfill that API when the native libc doesn't
> support that.
> The API is more important than who would implement it
>

if you're the only person implementing it _and_ the only person using it
... it doesn't really matter what you call it? just put _something_ in your
code, and worry about changing the name/signature if/when WG14 adds
something equivalent.


> >
> >>
> >> So my question, anyone in this threads have suggestion about the newly
> proposed API:
> >>
> >>  int mtx_timedlock_base (mtx_t*, int, const struct timespec*);
> >>  int cnd_timedwait_base (cnd_t*, mtx_t*, int, const struct timespec*);
> >
> >
> > don't existing functions put the `int __base` last? sounds like a
> question for WG14 rather than c library implementors though --- as long as
> this isn't supported on the platform that doesn't have pthreads, it's not
> filling any obvious need.
> >
> >>
> >> >
> >> >>
> >> >> If we have minimal agreement about this proposal, I'd like to add
> tests for it. But still, I don't think
> >> >> __USE_GNU is a good name for it, because it's for C2y or C3x, any
> better option for this, so that it's not GNU restricted, for example,
> suppose MSVC also wants to implement this?
> >> >>
> >> >>
> >> >> >
> >> >> > > +extern int __REDIRECT (mtx_timedlock_base, (mtx_t *__restrict
> __mutex,
> >> >> > > +                                            int time_base,
> >> >> > > +                                            const struct
> timespec *__restrict
> >> >> > > +                                            __time_point),
> >> >> > > +                       __mtx_timedlock_base64);
> >> >> >
> >> >> > Likewise, should be conditional on __USE_GNU and time_base should
> be
> >> >> > __time_base.
> >> >> >
> >> >> > > +extern int cnd_timedwait_base (cnd_t *__restrict __cond,
> >> >> > > +                               mtx_t *__restrict __mutex, int
> time_base,
> >> >> > > +                               const struct timespec
> *__restrict __time_point);
> >> >> >
> >> >> > > +extern int __REDIRECT (cnd_timedwait_base, (cnd_t *__restrict
> __cond,
> >> >> > > +                                            mtx_t *__restrict
> __mutex,
> >> >> > > +                                            int time_base,
> >> >> > > +                                            const struct
> timespec *__restrict
> >> >> > > +                                            __time_point),
> >> >> >
> >> >> > Likewise.
> >> >> >
> >> >> > --
> >> >> > Joseph S. Myers
> >> >> > joseph@codesourcery.com
> >> >>
> >> >>
> >> >>
> >> >> --
> >> >>          此致
> >> >> 礼
> >> >> 罗勇刚
> >> >> Yours
> >> >>     sincerely,
> >> >> Yonggang Luo
> >>
> >>
> >>
> >> --
> >>          此致
> >> 礼
> >> 罗勇刚
> >> Yours
> >>     sincerely,
> >> Yonggang Luo
>
>
>
> --
>          此致
> 礼
> 罗勇刚
> Yours
>     sincerely,
> Yonggang Luo
>