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Re: [PATCH v2] sysdeps/nanosleep: Use clock_nanosleep_time64 if avaliable


On Mon, Oct 28, 2019 at 8:51 PM Adhemerval Zanella
<adhemerval.zanella@linaro.org> wrote:
>
>
>
> On 24/10/2019 20:41, Alistair Francis wrote:
> > The nanosleep syscall is not supported on newer 32-bit platforms (such
> > as RV32). To fix this issue let's use clock_nanosleep_time64 if it is
> > avaliable.
> >
> > Let's use CLOCK_REALTIME when calling clock_nanosleep_time64 as the
> > Linux specification says:
> >   "POSIX.1 specifies that nanosleep() should measure time against the
> >    CLOCK_REALTIME clock. However, Linux measures the time using the
> >    CLOCK_MONOTONIC clock. This probably does not matter, since the POSIX.1
> >    specification for clock_settime(2) says that discontinuous changes in
> >    CLOCK_REALTIME should not affect nanosleep()"
> > ---
> > This was patch was runtime tested with RV32 and RV64
> > It was build tested using the ./scripts/build-many-glibcs.py script.
> >
> > I am currently running:
> > $ make ; make install ; make check
> > tests on native ARM (32-bit) with the following three confiugrations:
> >  - 4.19 Kernel and 4.19 Headers
> >  - 5.2 Kernel and 4.19 Headers
> >  - 5.2 Kernel and 5.2 Headers
> > I should have the results tomorrow.
> >
> > v2:
> >  - Explicitly include `#include <kernel-features.h>`
> >
> >  include/time.h                               | 20 ++++++
> >  nptl/thrd_sleep.c                            | 70 +++++++++++++++++--
> >  sysdeps/unix/sysv/linux/clock_nanosleep.c    | 73 ++++++++++++++++++--
> >  sysdeps/unix/sysv/linux/nanosleep.c          | 65 ++++++++++++++++-
> >  sysdeps/unix/sysv/linux/nanosleep_nocancel.c | 65 ++++++++++++++++-
> >  5 files changed, 280 insertions(+), 13 deletions(-)
> >
> > diff --git a/include/time.h b/include/time.h
> > index d93b16a7810..0e703f87cef 100644
> > --- a/include/time.h
> > +++ b/include/time.h
> > @@ -174,6 +174,26 @@ libc_hidden_proto (__difftime64)
> >
> >  extern double __difftime (time_t time1, time_t time0);
> >
> > +#if __TIMESIZE == 64
> > +# define __thrd_sleep_time64 thrd_sleep
> > +# define __clock_nanosleep_time64 __clock_nanosleep
> > +# define __nanosleep_time64 __nanosleep
> > +# define __nanosleep_nocancel_time64 __nanosleep_nocancel
> > +#else
> > +extern int __thrd_sleep_time64 (const struct __timespec64* time_point,
> > +                                struct __timespec64* remaining);
> > +libc_hidden_proto (__thrd_sleep_time64)
> > +extern int __clock_nanosleep_time64 (clockid_t clock_id,
> > +                                     int flags, const struct __timespec64 *req,
> > +                                     struct __timespec64 *rem);
> > +libc_hidden_proto (__clock_nanosleep_time64)
> > +extern  int __nanosleep_time64 (const struct __timespec64 *requested_time,
> > +                                struct __timespec64 *remaining);
> > +libc_hidden_proto (__nanosleep_time64)
> > +extern int __nanosleep_nocancel_time64 (const struct __timespec64 *requested_time,
> > +                                        struct __timespec64 *remaining);
> > +libc_hidden_proto (__nanosleep_nocancel_time64)
> > +#endif
> >
> >  /* Use in the clock_* functions.  Size of the field representing the
> >     actual clock ID.  */
> > diff --git a/nptl/thrd_sleep.c b/nptl/thrd_sleep.c
> > index 2e185dd748e..2a6bb1f9e3f 100644
> > --- a/nptl/thrd_sleep.c
> > +++ b/nptl/thrd_sleep.c
> > @@ -17,23 +17,85 @@
> >     <https://www.gnu.org/licenses/>.  */
> >
> >  #include <time.h>
> > +#include <kernel-features.h>
> >  #include <sysdep-cancel.h>
> >
> >  #include "thrd_priv.h"
> >
> >  int
> > -thrd_sleep (const struct timespec* time_point, struct timespec* remaining)
> > +__thrd_sleep_time64 (const struct __timespec64* time_point, struct __timespec64* remaining)
> >  {
> >    INTERNAL_SYSCALL_DECL (err);
> > -  int ret = INTERNAL_SYSCALL_CANCEL (nanosleep, err, time_point, remaining);
> > +  int ret = -1;
> > +
> > +#ifdef __ASSUME_TIME64_SYSCALLS
> > +# ifndef __NR_clock_nanosleep_time64
> > +#  define __NR_clock_nanosleep_time64 __NR_clock_nanosleep
> > +# endif
> > +  ret = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err, CLOCK_REALTIME,
> > +                                 0, time_point, remaining);
> > +#else
> > +# ifdef __NR_clock_nanosleep_time64
> > +  long int ret_64;
> > +
> > +  ret_64 = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err, CLOCK_REALTIME,
> > +                                    0, time_point, remaining);
> > +
> > +  if (ret_64 == 0 || errno != ENOSYS)
> > +    ret = ret_64;
> > +# endif /* __NR_clock_nanosleep_time64 */
> > +  if (ret < 0)
> > +    {
> > +      struct timespec tp32, tr32;
> > +
> > +      if (! in_time_t_range (time_point->tv_sec))
> > +        {
> > +          __set_errno (EOVERFLOW);
> > +          return -1;
> > +        }
> > +
> > +      tp32 = valid_timespec64_to_timespec (*time_point);
> > +      ret =  INTERNAL_SYSCALL_CANCEL (nanosleep, err, &tp32, &tr32);
> > +
> > +      if ((ret == 0 || errno != ENOSYS) && remaining)
> > +        *remaining = valid_timespec_to_timespec64 (tr32);
> > +    }
> > +#endif /* __ASSUME_TIME64_SYSCALLS */
> > +
> >    if (INTERNAL_SYSCALL_ERROR_P (ret, err))
> >      {
> >        /* C11 states thrd_sleep function returns -1 if it has been interrupted
> > -      by a signal, or a negative value if it fails.  */
> > +         by a signal, or a negative value if it fails.  */
> >        ret = INTERNAL_SYSCALL_ERRNO (ret, err);
> >        if (ret == EINTR)
> > -     return -1;
> > +        return -1;
> >        return -2;
> >      }
> >    return 0;
> >  }
>
> Wouldn't be simple to just call __clock_nanosleep_time64 instead of duplicate
> the syscall handling and the required error code for c11 thread?  Something
> like:
>
> int
> __thrd_sleep_time64 (const struct __timespec64* time_point,
>                      struct __timespec64* remaining)
> {
>   int ret = __clock_nanosleep (CLOCK_REALTIME, 0, time_point, remaining);
>   /* C11 states thrd_sleep function returns -1 if it has been interrupted
>      by a signal, or a negative value if it fails.  */
>   switch (ret)
>   {
>      case 0:      return 0;
>      case EINTR:  return -1;
>      default:     return -2;
>   }
> }

This looks good to me, I'll try that.

Alistair

>
> > +
> > +#if __TIMESIZE != 64
> > +int
> > +thrd_sleep (const struct timespec* time_point, struct timespec* remaining)
> > +{
> > +  int ret;
> > +  struct __timespec64 tp64, tr64;
> > +
> > +  tp64 = valid_timespec_to_timespec64 (*time_point);
> > +  ret = __thrd_sleep_time64 (&tp64, &tr64);
> > +
> > +  if (ret == 0 || errno != ENOSYS)
> > +    {
> > +      if (! in_time_t_range (tr64.tv_sec))
> > +        {
> > +          __set_errno (EOVERFLOW);
> > +          return -1;
> > +        }
> > +
> > +      if (remaining)
> > +        *remaining = valid_timespec64_to_timespec (tr64);
> > +    }
> > +
> > +  return ret;
> > +}
> > +#endif
> > diff --git a/sysdeps/unix/sysv/linux/clock_nanosleep.c b/sysdeps/unix/sysv/linux/clock_nanosleep.c
> > index 1f240b8720a..d257ea57fb0 100644
> > --- a/sysdeps/unix/sysv/linux/clock_nanosleep.c
> > +++ b/sysdeps/unix/sysv/linux/clock_nanosleep.c
> > @@ -16,6 +16,7 @@
> >     <https://www.gnu.org/licenses/>.  */
> >
> >  #include <time.h>
> > +#include <kernel-features.h>
> >  #include <errno.h>
> >
> >  #include <sysdep-cancel.h>
> > @@ -26,9 +27,11 @@
> >  /* We can simply use the syscall.  The CPU clocks are not supported
> >     with this function.  */
> >  int
> > -__clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
> > -                struct timespec *rem)
> > +__clock_nanosleep_time64 (clockid_t clock_id, int flags, const struct __timespec64 *req,
> > +                          struct __timespec64 *rem)
> >  {
> > +  int r = -1;
> > +
> >    if (clock_id == CLOCK_THREAD_CPUTIME_ID)
> >      return EINVAL;
> >    if (clock_id == CLOCK_PROCESS_CPUTIME_ID)
> > @@ -37,12 +40,72 @@ __clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
> >    /* If the call is interrupted by a signal handler or encounters an error,
> >       it returns a positive value similar to errno.  */
> >    INTERNAL_SYSCALL_DECL (err);
> > -  int r = INTERNAL_SYSCALL_CANCEL (clock_nanosleep, err, clock_id, flags,
> > -                                req, rem);
> > +
> > +#ifdef __ASSUME_TIME64_SYSCALLS
> > +# ifndef __NR_clock_nanosleep_time64
> > +#  define __NR_clock_nanosleep_time64 __NR_clock_nanosleep
> > +# endif
> > +  r = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err, clock_id,
> > +                               flags, req, rem);
> > +#else
> > +# ifdef __NR_clock_nanosleep_time64
> > +  long int ret_64;
> > +
> > +  ret_64 = INTERNAL_SYSCALL_CANCEL (clock_nanosleep_time64, err, clock_id,
> > +                                    flags, req, rem);
> > +
> > +  if (ret_64 == 0 || errno != ENOSYS)
> > +    r = ret_64;
> > +# endif /* __NR_clock_nanosleep_time64 */
> > +  if (r < 0)
> > +    {
> > +      struct timespec ts32, tr32;
> > +
> > +      if (! in_time_t_range (req->tv_sec))
> > +        {
> > +          __set_errno (EOVERFLOW);
> > +          return -1;
> > +        }
> > +
> > +      ts32 = valid_timespec64_to_timespec (*req);
> > +      r =  INTERNAL_SYSCALL_CANCEL (clock_nanosleep, err, &ts32, &tr32);
> > +
> > +      if ((r == 0 || errno != ENOSYS) && rem)
> > +        *rem = valid_timespec_to_timespec64 (tr32);
> > +    }
> > +#endif /* __ASSUME_TIME64_SYSCALLS */
> > +
> >    return (INTERNAL_SYSCALL_ERROR_P (r, err)
> > -       ? INTERNAL_SYSCALL_ERRNO (r, err) : 0);
> > +          ? INTERNAL_SYSCALL_ERRNO (r, err) : 0);
> >  }
> >
> > +#if __TIMESIZE != 64
> > +int
> > +__clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
> > +                   struct timespec *rem)
> > +{
> > +  int r;
> > +  struct __timespec64 treq64, trem64;
> > +
> > +  treq64 = valid_timespec_to_timespec64 (*req);
> > +  r = __clock_nanosleep_time64 (clock_id, flags, &treq64, &trem64);
> > +
> > +  if (r == 0 || errno != ENOSYS)
> > +    {
> > +      if (! in_time_t_range (trem64.tv_sec))
> > +        {
> > +          __set_errno (EOVERFLOW);
> > +          return -1;
> > +        }
> > +
> > +      if (rem)
> > +        *rem = valid_timespec64_to_timespec (trem64);
> > +    }
> > +
> > +  return r;
> > +}
> > +#endif
> > +
> >  versioned_symbol (libc, __clock_nanosleep, clock_nanosleep, GLIBC_2_17);
> >  /* clock_nanosleep moved to libc in version 2.17;
> >     old binaries may expect the symbol version it had in librt.  */
> > diff --git a/sysdeps/unix/sysv/linux/nanosleep.c b/sysdeps/unix/sysv/linux/nanosleep.c
> > index 6787909248f..10a6d57a1de 100644
> > --- a/sysdeps/unix/sysv/linux/nanosleep.c
> > +++ b/sysdeps/unix/sysv/linux/nanosleep.c
> > @@ -17,15 +17,76 @@
> >     <https://www.gnu.org/licenses/>.  */
> >
> >  #include <time.h>
> > +#include <kernel-features.h>
> >  #include <sysdep-cancel.h>
> >  #include <not-cancel.h>
> >
> >  /* Pause execution for a number of nanoseconds.  */
> >  int
> > +__nanosleep_time64 (const struct __timespec64 *requested_time,
> > +                    struct __timespec64 *remaining)
> > +{
> > +#if defined(__ASSUME_TIME64_SYSCALLS)
> > +# ifndef __NR_clock_nanosleep_time64
> > +#  define __NR_clock_nanosleep_time64 __NR_clock_nanosleep
> > +# endif
> > +  return SYSCALL_CANCEL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
> > +                         requested_time, remaining);
> > +#else
> > +# ifdef __NR_clock_nanosleep_time64
> > +  long int ret_64;
> > +
> > +  ret_64 = SYSCALL_CANCEL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
> > +                           requested_time, remaining);
> > +
> > +  if (ret_64 == 0 || errno != ENOSYS)
> > +    return ret_64;
> > +# endif /* __NR_clock_nanosleep_time64 */
> > +  int ret;
> > +  struct timespec ts32, tr32;
> > +
> > +  if (! in_time_t_range (requested_time->tv_sec))
> > +    {
> > +      __set_errno (EOVERFLOW);
> > +      return -1;
> > +    }
> > +
> > +  ts32 = valid_timespec64_to_timespec (*requested_time);
> > +  ret = SYSCALL_CANCEL (nanosleep, &ts32, &tr32);
> > +
> > +  if ((ret == 0 || errno != ENOSYS) && remaining)
> > +    *remaining = valid_timespec_to_timespec64 (tr32);
> > +
> > +  return ret;
> > +#endif /* __ASSUME_TIME64_SYSCALLS */
> > +}
> > +
> > +#if __TIMESIZE != 64
> > +int
> >  __nanosleep (const struct timespec *requested_time,
> > -          struct timespec *remaining)
> > +             struct timespec *remaining)
> >  {
> > -  return SYSCALL_CANCEL (nanosleep, requested_time, remaining);
> > +  int r;
> > +  struct __timespec64 treq64, trem64;
> > +
> > +  treq64 = valid_timespec_to_timespec64 (*requested_time);
> > +  r = __nanosleep_time64 (&treq64, &trem64);
> > +
> > +  if (r == 0 || errno != ENOSYS)
> > +    {
> > +      if (! in_time_t_range (trem64.tv_sec))
> > +        {
> > +          __set_errno (EOVERFLOW);
> > +          return -1;
> > +        }
> > +
> > +      if (remaining)
> > +        *remaining = valid_timespec64_to_timespec (trem64);
> > +    }
> > +
> > +  return r;
> >  }
> > +#endif
> > +
> >  hidden_def (__nanosleep)
> >  weak_alias (__nanosleep, nanosleep)
> > diff --git a/sysdeps/unix/sysv/linux/nanosleep_nocancel.c b/sysdeps/unix/sysv/linux/nanosleep_nocancel.c
> > index d6442bf4f7f..1a6c6c0a48a 100644
> > --- a/sysdeps/unix/sysv/linux/nanosleep_nocancel.c
> > +++ b/sysdeps/unix/sysv/linux/nanosleep_nocancel.c
> > @@ -17,13 +17,74 @@
> >     <https://www.gnu.org/licenses/>.  */
> >
> >  #include <time.h>
> > +#include <kernel-features.h>
> >  #include <sysdep-cancel.h>
> >  #include <not-cancel.h>
> >
> > +int
> > +__nanosleep_nocancel_time64 (const struct __timespec64 *requested_time,
> > +                             struct __timespec64 *remaining)
> > +{
> > +#ifdef __ASSUME_TIME64_SYSCALLS
> > +# ifndef __NR_clock_nanosleep_time64
> > +#  define __NR_clock_nanosleep_time64 __NR_clock_nanosleep
> > +# endif
> > +  return INLINE_SYSCALL_CALL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
> > +                              requested_time, remaining);
> > +#else
> > +# ifdef __NR_clock_nanosleep_time64
> > +  long int ret_64;
> > +
> > +  ret_64 = INLINE_SYSCALL_CALL (clock_nanosleep_time64, CLOCK_REALTIME, 0,
> > +                                requested_time, remaining);
> > +
> > +  if (ret_64 == 0 || errno != ENOSYS)
> > +    return ret_64;
> > +# endif /* __NR_clock_nanosleep_time64 */
> > +  int ret;
> > +  struct timespec ts32, tr32;
> > +
> > +  if (! in_time_t_range (requested_time->tv_sec))
> > +    {
> > +      __set_errno (EOVERFLOW);
> > +      return -1;
> > +    }
> > +
> > +  ts32 = valid_timespec64_to_timespec (*requested_time);
> > +  ret = INLINE_SYSCALL_CALL (nanosleep, &ts32, &tr32);
> > +
> > +  if (ret == 0 || errno != ENOSYS)
> > +    *remaining = valid_timespec_to_timespec64 (tr32);
> > +
> > +  return ret;
> > +#endif /* __ASSUME_TIME64_SYSCALLS */
> > +}
> > +
> > +#if __TIMESIZE != 64
> >  int
> >  __nanosleep_nocancel (const struct timespec *requested_time,
> > -                   struct timespec *remaining)
> > +                      struct timespec *remaining)
> >  {
> > -  return INLINE_SYSCALL_CALL (nanosleep, requested_time, remaining);
> > +  int ret;
> > +  struct __timespec64 treq64, trem64;
> > +
> > +  treq64 = valid_timespec_to_timespec64 (*requested_time);
> > +  ret = __nanosleep_nocancel_time64 (&treq64, &trem64);
> > +
> > +  if (ret == 0 || errno != ENOSYS)
> > +    {
> > +      if (! in_time_t_range (trem64.tv_sec))
> > +        {
> > +          __set_errno (EOVERFLOW);
> > +          return -1;
> > +        }
> > +
> > +      if (remaining)
> > +        *remaining = valid_timespec64_to_timespec (trem64);
> > +    }
> > +
> > +  return ret;
> >  }
> > +#endif
> > +
> >  hidden_def (__nanosleep_nocancel)
> >


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