[PATCH 2/2] y2038: Convert aio_suspend to support 64 bit time
Alistair Francis
alistair23@gmail.com
Thu Oct 29 17:03:38 GMT 2020
On Thu, Oct 29, 2020 at 7:47 AM Lukasz Majewski <lukma@denx.de> wrote:
>
> The aio_suspend function has been converted to support 64 bit time. It was
> also necessary to provide Linux specific copy of aio_suspend.c to avoid
> problems on i686-gnu (i.e. HURD) port, which is not providing
> pthread_cond_timedwait() supporting 64 bit time.
>
> This change uses:
> - New __futex_reltimed_wait64 (instead of futex_reltimed_wait)
> - New __futex_reltimed_wait_cancellable64
> (instead of futex_reltimed_wait_cancellable)
> from ./sysdeps/nptl/futex-helpers.h
>
> The aio_suspend() accepts relative timeout.
>
> The __aio_suspend() is supposed to be run on ports with __TIMESIZE !=64 and
> __WORDSIZE==32. It internally utilizes __aio_suspend_time64() and hence the
> conversion from 32 bit struct timespec to 64 bit one is required.
>
> For ports supporting 64 bit time the __aio_suspend_time64() will be used
> either via alias (to __aio_suspend when __TIMESIZE==64) or redirection
> (when -D_TIME_BITS=64 is passed).
>
> Build tests:
> ./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Alistair
> ---
> include/aio.h | 8 +++
> sysdeps/nptl/aio_misc.h | 4 +-
> sysdeps/nptl/futex-internal.h | 87 +++++++++++++++++++++++++++
> sysdeps/unix/sysv/linux/aio_suspend.c | 41 ++++++++++---
> 4 files changed, 130 insertions(+), 10 deletions(-)
>
> diff --git a/include/aio.h b/include/aio.h
> index 90c74f9951..c7f4233310 100644
> --- a/include/aio.h
> +++ b/include/aio.h
> @@ -9,6 +9,14 @@ extern void __aio_init (const struct aioinit *__init);
> lio_listio and we do not issue events for each individual list
> element. */
> #define LIO_NO_INDIVIDUAL_EVENT 128
> +
> +# if __TIMESIZE == 64
> +# define __aio_suspend_time64 __aio_suspend
> +# else
> +extern int __aio_suspend_time64 (const struct aiocb *const list[], int nent,
> + const struct __timespec64 *timeout);
> +librt_hidden_proto (__aio_suspend_time64)
> +# endif
> #endif
>
> #endif
> diff --git a/sysdeps/nptl/aio_misc.h b/sysdeps/nptl/aio_misc.h
> index 3f195f4794..5c553cce56 100644
> --- a/sysdeps/nptl/aio_misc.h
> +++ b/sysdeps/nptl/aio_misc.h
> @@ -45,10 +45,10 @@
> do \
> { \
> if (cancel) \
> - status = futex_reltimed_wait_cancelable ( \
> + status = __futex_reltimed_wait_cancelable64 ( \
> (unsigned int *) futexaddr, oldval, timeout, FUTEX_PRIVATE); \
> else \
> - status = futex_reltimed_wait ((unsigned int *) futexaddr, \
> + status = __futex_reltimed_wait64 ((unsigned int *) futexaddr, \
> oldval, timeout, FUTEX_PRIVATE); \
> if (status != EAGAIN) \
> break; \
> diff --git a/sysdeps/nptl/futex-internal.h b/sysdeps/nptl/futex-internal.h
> index cd356e4fa8..1535509e71 100644
> --- a/sysdeps/nptl/futex-internal.h
> +++ b/sysdeps/nptl/futex-internal.h
> @@ -608,4 +608,91 @@ __futex_clock_wait_bitset64 (int *futexp, int val, clockid_t clockid,
> const struct __timespec64 *abstime,
> int private) attribute_hidden;
>
> +static __always_inline int
> +__futex_reltimed_wait64 (unsigned int* futex_word, unsigned int expected,
> + const struct __timespec64* reltime, int private)
> +{
> + int err = INTERNAL_SYSCALL_CALL (futex_time64, futex_word,
> + __lll_private_flag (FUTEX_WAIT, private),
> + expected, reltime);
> +#ifndef __ASSUME_TIME64_SYSCALLS
> + if (err == -ENOSYS)
> + {
> + if (in_time_t_range (reltime->tv_sec))
> + {
> + struct timespec ts32 = valid_timespec64_to_timespec (*reltime);
> +
> + err = INTERNAL_SYSCALL_CALL (futex, futex_word,
> + __lll_private_flag (FUTEX_WAIT,
> + private),
> + expected, &ts32);
> + }
> + else
> + err = -EOVERFLOW;
> + }
> +#endif
> + switch (err)
> + {
> + case 0:
> + case -EAGAIN:
> + case -EINTR:
> + case -ETIMEDOUT:
> + return -err;
> +
> + case -EFAULT: /* Must have been caused by a glibc or application bug. */
> + case -EINVAL: /* Either due to wrong alignment 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 ();
> + }
> +}
> +
> +/* Like futex_reltimed_wait but is a POSIX cancellation point. */
> +static __always_inline int
> +__futex_reltimed_wait_cancelable64 (unsigned int* futex_word,
> + unsigned int expected,
> + const struct __timespec64* reltime,
> + int private)
> +{
> + int err = INTERNAL_SYSCALL_CANCEL (futex_time64, futex_word,
> + __lll_private_flag (FUTEX_WAIT, private),
> + expected, reltime);
> +#ifndef __ASSUME_TIME64_SYSCALLS
> + if (err == -ENOSYS)
> + {
> + if (in_time_t_range (reltime->tv_sec))
> + {
> + struct timespec ts32 = valid_timespec64_to_timespec (*reltime);
> +
> + err = INTERNAL_SYSCALL_CANCEL (futex, futex_word,
> + __lll_private_flag (FUTEX_WAIT,
> + private),
> + expected, &ts32);
> + }
> + else
> + err = -EOVERFLOW;
> + }
> +#endif
> + switch (err)
> + {
> + case 0:
> + case -EAGAIN:
> + case -EINTR:
> + case -ETIMEDOUT:
> + return -err;
> +
> + case -EFAULT: /* Must have been caused by a glibc or application bug. */
> + case -EINVAL: /* Either due to wrong alignment 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 ();
> + }
> +}
> +
> #endif /* futex-internal.h */
> diff --git a/sysdeps/unix/sysv/linux/aio_suspend.c b/sysdeps/unix/sysv/linux/aio_suspend.c
> index ad03f13558..8ce7bfedb0 100644
> --- a/sysdeps/unix/sysv/linux/aio_suspend.c
> +++ b/sysdeps/unix/sysv/linux/aio_suspend.c
> @@ -94,7 +94,7 @@ cleanup (void *arg)
> #ifdef DONT_NEED_AIO_MISC_COND
> static int
> __attribute__ ((noinline))
> -do_aio_misc_wait (unsigned int *cntr, const struct timespec *timeout)
> +do_aio_misc_wait (unsigned int *cntr, const struct __timespec64 *timeout)
> {
> int result = 0;
>
> @@ -105,8 +105,8 @@ do_aio_misc_wait (unsigned int *cntr, const struct timespec *timeout)
> #endif
>
> int
> -aio_suspend (const struct aiocb *const list[], int nent,
> - const struct timespec *timeout)
> +__aio_suspend_common64 (const struct aiocb *const list[], int nent,
> + const struct __timespec64 *timeout)
> {
> if (__glibc_unlikely (nent < 0))
> {
> @@ -183,10 +183,10 @@ aio_suspend (const struct aiocb *const list[], int nent,
> {
> /* We have to convert the relative timeout value into an
> absolute time value with pthread_cond_timedwait expects. */
> - struct timespec now;
> - struct timespec abstime;
> + struct __timespec64 now;
> + struct __timespec64 abstime;
>
> - __clock_gettime (CLOCK_REALTIME, &now);
> + __clock_gettime64 (CLOCK_REALTIME, &now);
> abstime.tv_nsec = timeout->tv_nsec + now.tv_nsec;
> abstime.tv_sec = timeout->tv_sec + now.tv_sec;
> if (abstime.tv_nsec >= 1000000000)
> @@ -195,8 +195,8 @@ aio_suspend (const struct aiocb *const list[], int nent,
> abstime.tv_sec += 1;
> }
>
> - result = pthread_cond_timedwait (&cond, &__aio_requests_mutex,
> - &abstime);
> + result = __pthread_cond_timedwait64 (&cond, &__aio_requests_mutex,
> + &abstime);
> }
> #endif
>
> @@ -250,4 +250,29 @@ aio_suspend (const struct aiocb *const list[], int nent,
> return result;
> }
>
> +int
> +__aio_suspend_time64 (const struct aiocb *const list[], int nent,
> + const struct __timespec64 *timeout)
> +{
> + return __aio_suspend_common64 (list, nent, timeout);
> +}
> +
> +#if __TIMESIZE != 64
> +librt_hidden_def (__aio_suspend_time64)
> +
> +int
> +__aio_suspend(const struct aiocb *const list[], int nent,
> + const struct timespec *timeout)
> +{
> + struct __timespec64 ts64;
> +
> + if (timeout != NULL)
> + {
> + ts64 = valid_timespec_to_timespec64 (*timeout);
> + }
> +
> + return __aio_suspend_time64 (list, nent, timeout != NULL ? &ts64 : NULL);
> +}
> +#endif
> +weak_alias (__aio_suspend, aio_suspend)
> weak_alias (aio_suspend, aio_suspend64)
> --
> 2.20.1
>
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