Re: [PATCH 05/13] linux: nptl: Consolidate __futex_abstimed_wait_{cancelable}64

[Lukasz Majewski <lukma@denx.de>]

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Hi Adhemerval,

> The only different is how to issue the syscall.
> 
> Checked on x86_64-linux-gnu and i686-linux-gnu.
> ---
>  sysdeps/nptl/futex-internal.c | 111
> +++++++++++----------------------- 1 file changed, 35 insertions(+),
> 76 deletions(-)
> 
> diff --git a/sysdeps/nptl/futex-internal.c
> b/sysdeps/nptl/futex-internal.c index e4a14b477c..f9a2e28ee6 100644
> --- a/sysdeps/nptl/futex-internal.c
> +++ b/sysdeps/nptl/futex-internal.c
> @@ -24,10 +24,10 @@
>  
>  #ifndef __ASSUME_TIME64_SYSCALLS
>  static int
> -__futex_abstimed_wait_cancelable32 (unsigned int* futex_word,
> -                                    unsigned int expected, int op,
> -                                    const struct __timespec64*
> abstime,
> -                                    int private)
> +__futex_abstimed_wait_common32 (unsigned int* futex_word,
> +                                unsigned int expected, int op,
> +                                const struct __timespec64* abstime,
> +                                int private, bool cancel)
>  {
>    struct timespec ts32, *pts32 = NULL;
>    if (abstime != NULL)
> @@ -39,34 +39,16 @@ __futex_abstimed_wait_cancelable32 (unsigned int*
> futex_word, pts32 = &ts32;
>      }
>  
> -  return INTERNAL_SYSCALL_CANCEL (futex, futex_word, op, expected,
> +  if (cancel)
> +    return INTERNAL_SYSCALL_CANCEL (futex, futex_word, op, expected,
> +                                    pts32, NULL /* Unused.  */,
> +                                    FUTEX_BITSET_MATCH_ANY);
> +  else
> +    return INTERNAL_SYSCALL_CALL (futex, futex_word, op, expected,
>                                    pts32, NULL /* Unused.  */,
>                                    FUTEX_BITSET_MATCH_ANY);
>  }
>  
> -static int
> -__futex_abstimed_wait32 (unsigned int* futex_word,
> -                         unsigned int expected, clockid_t clockid,
> -                         const struct __timespec64* abstime,
> -                         int private)
> -{
> -  struct timespec ts32;
> -
> -  if (abstime != NULL && ! in_time_t_range (abstime->tv_sec))
> -    return -EOVERFLOW;
> -
> -  unsigned int clockbit = (clockid == CLOCK_REALTIME) ?
> -    FUTEX_CLOCK_REALTIME : 0;
> -  int op = __lll_private_flag (FUTEX_WAIT_BITSET | clockbit,
> private); -
> -  if (abstime != NULL)
> -    ts32 = valid_timespec64_to_timespec (*abstime);
> -
> -  return INTERNAL_SYSCALL_CALL (futex, futex_word, op, expected,
> -                                abstime != NULL ? &ts32 : NULL,
> -                                NULL /* Unused.  */,
> FUTEX_BITSET_MATCH_ANY); -}
> -
>  static int
>  __futex_clock_wait_bitset32 (int *futexp, int val, clockid_t clockid,
>                               const struct __timespec64 *abstime, int
> private) @@ -89,11 +71,11 @@ __futex_clock_wait_bitset32 (int
> *futexp, int val, clockid_t clockid, }
>  #endif /* ! __ASSUME_TIME64_SYSCALLS */
>  
> -int
> -__futex_abstimed_wait_cancelable64 (unsigned int* futex_word,
> -                                    unsigned int expected, clockid_t
> clockid,
> -                                    const struct __timespec64*
> abstime,
> -                                    int private)
> +static int
> +__futex_abstimed_wait_common64 (unsigned int* futex_word,
> +                                unsigned int expected, clockid_t
> clockid,
> +                                const struct __timespec64* abstime,
> +                                int private, bool cancel)
>  {
>    unsigned int clockbit;
>    int err;
> @@ -109,13 +91,18 @@ __futex_abstimed_wait_cancelable64 (unsigned
> int* futex_word, clockbit = (clockid == CLOCK_REALTIME) ?
> FUTEX_CLOCK_REALTIME : 0; int op = __lll_private_flag
> (FUTEX_WAIT_BITSET | clockbit, private); 
> -  err = INTERNAL_SYSCALL_CANCEL (futex_time64, futex_word, op,
> expected,
> -                                 abstime, NULL /* Unused.  */,
> +  if (cancel)
> +    err = INTERNAL_SYSCALL_CANCEL (futex_time64, futex_word, op,
> expected,
> +                                   abstime, NULL /* Unused.  */,
> +                                   FUTEX_BITSET_MATCH_ANY);
> +  else
> +    err = INTERNAL_SYSCALL_CALL (futex_time64, futex_word, op,
> expected,
> +                                 abstime, NULL /* Ununsed.  */,
>                                   FUTEX_BITSET_MATCH_ANY);
>  #ifndef __ASSUME_TIME64_SYSCALLS
>    if (err == -ENOSYS)
> -    err = __futex_abstimed_wait_cancelable32 (futex_word, expected,
> -                                              op, abstime, private);
> +    err = __futex_abstimed_wait_common32 (futex_word, expected, op,
> abstime,
> +                                          private, cancel);
>  #endif
>  
>    switch (err)
> @@ -145,46 +132,18 @@ __futex_abstimed_wait64 (unsigned int*
> futex_word, unsigned int expected, clockid_t clockid,
>                           const struct __timespec64* abstime, int
> private) {
> -  unsigned int clockbit;
> -  int err;
> -
> -  /* Work around the fact that the kernel rejects negative timeout
> values
> -     despite them being valid.  */
> -  if (__glibc_unlikely ((abstime != NULL) && (abstime->tv_sec < 0)))
> -    return ETIMEDOUT;
> -
> -  if (! lll_futex_supported_clockid (clockid))
> -    return EINVAL;
> -
> -  clockbit = (clockid == CLOCK_REALTIME) ? FUTEX_CLOCK_REALTIME : 0;
> -  int op = __lll_private_flag (FUTEX_WAIT_BITSET | clockbit,
> private); -
> -  err = INTERNAL_SYSCALL_CALL (futex_time64, futex_word, op,
> expected,
> -                               abstime, NULL /* Unused.  */,
> -                               FUTEX_BITSET_MATCH_ANY);
> -#ifndef __ASSUME_TIME64_SYSCALLS
> -  if (err == -ENOSYS)
> -    err = __futex_abstimed_wait32 (futex_word, expected,
> -                                   clockid, abstime, private);
> -#endif
> -  switch (err)
> -    {
> -    case 0:
> -    case -EAGAIN:
> -    case -EINTR:
> -    case -ETIMEDOUT:
> -      return -err;
> +  return __futex_abstimed_wait_common64 (futex_word, expected,
> clockid,
> +                                         abstime, private, false);
> +}
>  
> -    case -EFAULT: /* Must have been caused by a glibc or application
> bug.  */
> -    case -EINVAL: /* Either due to wrong alignment, unsupported
> -		     clockid or due to the timeout not being
> -		     normalized. Must have been caused by a glibc or
> -		     application bug.  */
> -    case -ENOSYS: /* Must have been caused by a glibc bug.  */
> -    /* No other errors are documented at this time.  */
> -    default:
> -      futex_fatal_error ();
> -    }
> +int
> +__futex_abstimed_wait_cancelable64 (unsigned int* futex_word,
> +                                    unsigned int expected, clockid_t
> clockid,
> +                                    const struct __timespec64*
> abstime,
> +                                    int private)
> +{
> +  return __futex_abstimed_wait_common64 (futex_word, expected,
> clockid,
> +                                         abstime, private, true);
>  }
>  
>  int

Thanks for making this consolidation. Indeed there is now only
difference in issuing the syscall.

Reviewed-by: Lukasz Majewski <lukma@denx.de>


Best regards,

Lukasz Majewski

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