mirror of
https://sourceware.org/git/glibc.git
synced 2025-06-13 19:21:36 +03:00
99d01ffcc3
In preparation for adding POSIX clockwait variants of timedwait functions, add a clockid_t parameter to futex_abstimed_wait functions and pass CLOCK_REALTIME from all callers for the time being. Replace lll_futex_timed_wait_bitset with lll_futex_clock_wait_bitset which takes a clockid_t parameter rather than the magic clockbit. * sysdeps/nptl/lowlevellock-futex.h, sysdeps/unix/sysv/linux/lowlevellock-futex.h: Replace lll_futex_timed_wait_bitset with lll_futex_clock_wait_bitset that takes a clockid rather than a special clockbit. * sysdeps/nptl/lowlevellock-futex.h: Add lll_futex_supported_clockid so that client functions can check whether their clockid parameter is valid even if they don't ultimately end up calling lll_futex_clock_wait_bitset. * sysdeps/nptl/futex-internal.h, sysdeps/unix/sysv/linux/futex-internal.h (futex_abstimed_wait, futex_abstimed_wait_cancelable): Add clockid_t parameter to indicate which clock the absolute time passed should be measured against. Pass that clockid onto lll_futex_clock_wait_bitset. Add invalid clock as reason for returning -EINVAL. * sysdeps/nptl/futex-internal.h, sysdeps/unix/sysv/linux/futex-internal.h: Introduce futex_abstimed_supported_clockid so that client functions can check whether their clockid parameter is valid even if they don't ultimately end up calling futex_abstimed_wait. * nptl/pthread_cond_wait.c (__pthread_cond_wait_common): Remove code to calculate relative timeout for __PTHREAD_COND_CLOCK_MONOTONIC_MASK and just pass CLOCK_MONOTONIC or CLOCK_REALTIME as required to futex_abstimed_wait_cancelable. * nptl/pthread_rwlock_common (__pthread_rwlock_rdlock_full) (__pthread_wrlock_full), nptl/sem_waitcommon (do_futex_wait): Pass additional CLOCK_REALTIME to futex_abstimed_wait_cancelable. * nptl/pthread_mutex_timedlock.c (__pthread_mutex_timedlock): Switch to lll_futex_clock_wait_bitset and pass CLOCK_REALTIME Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
264 lines
8.5 KiB
C
264 lines
8.5 KiB
C
/* futex operations for glibc-internal use. Linux version.
|
|
Copyright (C) 2014-2019 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#ifndef FUTEX_INTERNAL_H
|
|
#define FUTEX_INTERNAL_H
|
|
|
|
#include <sysdeps/nptl/futex-internal.h>
|
|
#include <errno.h>
|
|
#include <lowlevellock-futex.h>
|
|
#include <sysdep-cancel.h>
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for documentation; this file only
|
|
contains Linux-specific comments.
|
|
|
|
The Linux kernel treats provides absolute timeouts based on the
|
|
CLOCK_REALTIME clock and relative timeouts measured against the
|
|
CLOCK_MONOTONIC clock.
|
|
|
|
We expect a Linux kernel version of 2.6.22 or more recent (since this
|
|
version, EINTR is not returned on spurious wake-ups anymore). */
|
|
|
|
/* FUTEX_SHARED is always supported by the Linux kernel. */
|
|
static __always_inline int
|
|
futex_supports_pshared (int pshared)
|
|
{
|
|
if (__glibc_likely (pshared == PTHREAD_PROCESS_PRIVATE))
|
|
return 0;
|
|
else if (pshared == PTHREAD_PROCESS_SHARED)
|
|
return 0;
|
|
else
|
|
return EINVAL;
|
|
}
|
|
|
|
/* The Linux kernel supports relative timeouts measured against the
|
|
CLOCK_MONOTONIC clock. */
|
|
static __always_inline bool
|
|
futex_supports_exact_relative_timeouts (void)
|
|
{
|
|
return true;
|
|
}
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for details. */
|
|
static __always_inline int
|
|
futex_wait (unsigned int *futex_word, unsigned int expected, int private)
|
|
{
|
|
int err = lll_futex_timed_wait (futex_word, expected, NULL, private);
|
|
switch (err)
|
|
{
|
|
case 0:
|
|
case -EAGAIN:
|
|
case -EINTR:
|
|
return -err;
|
|
|
|
case -ETIMEDOUT: /* Cannot have happened as we provided no timeout. */
|
|
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 ();
|
|
}
|
|
}
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for details. */
|
|
static __always_inline int
|
|
futex_wait_cancelable (unsigned int *futex_word, unsigned int expected,
|
|
int private)
|
|
{
|
|
int oldtype;
|
|
oldtype = __pthread_enable_asynccancel ();
|
|
int err = lll_futex_timed_wait (futex_word, expected, NULL, private);
|
|
__pthread_disable_asynccancel (oldtype);
|
|
switch (err)
|
|
{
|
|
case 0:
|
|
case -EAGAIN:
|
|
case -EINTR:
|
|
return -err;
|
|
|
|
case -ETIMEDOUT: /* Cannot have happened as we provided no timeout. */
|
|
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 ();
|
|
}
|
|
}
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for details. */
|
|
static __always_inline int
|
|
futex_reltimed_wait (unsigned int *futex_word, unsigned int expected,
|
|
const struct timespec *reltime, int private)
|
|
{
|
|
int err = lll_futex_timed_wait (futex_word, expected, reltime, private);
|
|
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 ();
|
|
}
|
|
}
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for details. */
|
|
static __always_inline int
|
|
futex_reltimed_wait_cancelable (unsigned int *futex_word,
|
|
unsigned int expected,
|
|
const struct timespec *reltime, int private)
|
|
{
|
|
int oldtype;
|
|
oldtype = LIBC_CANCEL_ASYNC ();
|
|
int err = lll_futex_timed_wait (futex_word, expected, reltime, private);
|
|
LIBC_CANCEL_RESET (oldtype);
|
|
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 ();
|
|
}
|
|
}
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for details. */
|
|
static __always_inline int
|
|
futex_abstimed_supported_clockid (clockid_t clockid)
|
|
{
|
|
return lll_futex_supported_clockid (clockid);
|
|
}
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for details. */
|
|
static __always_inline int
|
|
futex_abstimed_wait (unsigned int *futex_word, unsigned int expected,
|
|
clockid_t clockid,
|
|
const struct timespec *abstime, int private)
|
|
{
|
|
/* 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;
|
|
int err = lll_futex_clock_wait_bitset (futex_word, expected,
|
|
clockid, abstime,
|
|
private);
|
|
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, 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 ();
|
|
}
|
|
}
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for details. */
|
|
static __always_inline int
|
|
futex_abstimed_wait_cancelable (unsigned int *futex_word,
|
|
unsigned int expected,
|
|
clockid_t clockid,
|
|
const struct timespec *abstime, int private)
|
|
{
|
|
/* 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;
|
|
int oldtype;
|
|
oldtype = __pthread_enable_asynccancel ();
|
|
int err = lll_futex_clock_wait_bitset (futex_word, expected,
|
|
clockid, abstime,
|
|
private);
|
|
__pthread_disable_asynccancel (oldtype);
|
|
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 ();
|
|
}
|
|
}
|
|
|
|
/* See sysdeps/nptl/futex-internal.h for details. */
|
|
static __always_inline void
|
|
futex_wake (unsigned int *futex_word, int processes_to_wake, int private)
|
|
{
|
|
int res = lll_futex_wake (futex_word, processes_to_wake, private);
|
|
/* No error. Ignore the number of woken processes. */
|
|
if (res >= 0)
|
|
return;
|
|
switch (res)
|
|
{
|
|
case -EFAULT: /* Could have happened due to memory reuse. */
|
|
case -EINVAL: /* Could be either due to incorrect alignment (a bug in
|
|
glibc or in the application) or due to memory being
|
|
reused for a PI futex. We cannot distinguish between the
|
|
two causes, and one of them is correct use, so we do not
|
|
act in this case. */
|
|
return;
|
|
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 */
|