glibc/hurd/hurdlock.h

126 lines
4.7 KiB
C

/* Low-level lock implementation. High-level Hurd helpers.
Copyright (C) 1999-2020 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
<https://www.gnu.org/licenses/>. */
#ifndef _HURD_LOCK_H
#define _HURD_LOCK_H 1
#include <mach/lowlevellock.h>
struct timespec;
/* Flags for robust locks. */
#define LLL_WAITERS (1U << 31)
#define LLL_DEAD_OWNER (1U << 30)
#define LLL_OWNER_MASK ~(LLL_WAITERS | LLL_DEAD_OWNER)
/* Wait on 64-bit address PTR, without blocking if its contents
are different from the pair <LO, HI>. */
#define lll_xwait(ptr, lo, hi, flags) \
__gsync_wait (__mach_task_self (), \
(vm_offset_t)ptr, lo, hi, 0, flags | GSYNC_QUAD)
/* Same as 'lll_wait', but only block for MLSEC milliseconds. */
#define lll_timed_wait(ptr, val, mlsec, flags) \
__gsync_wait (__mach_task_self (), \
(vm_offset_t)ptr, val, 0, mlsec, flags | GSYNC_TIMED)
/* Same as 'lll_xwait', but only block for MLSEC milliseconds. */
#define lll_timed_xwait(ptr, lo, hi, mlsec, flags) \
__gsync_wait (__mach_task_self (), (vm_offset_t)ptr, \
lo, hi, mlsec, flags | GSYNC_TIMED | GSYNC_QUAD)
/* Same as 'lll_wait', but only block until TSP elapses,
using clock CLK. */
extern int __lll_abstimed_wait (void *__ptr, int __val,
const struct timespec *__tsp, int __flags, int __clk);
/* Same as 'lll_xwait', but only block until TSP elapses,
using clock CLK. */
extern int __lll_abstimed_xwait (void *__ptr, int __lo, int __hi,
const struct timespec *__tsp, int __flags, int __clk);
/* Same as 'lll_lock', but return with an error if TSP elapses,
using clock CLK. */
extern int __lll_abstimed_lock (void *__ptr,
const struct timespec *__tsp, int __flags, int __clk);
/* Acquire the lock at PTR, but return with an error if
the process containing the owner thread dies. */
extern int __lll_robust_lock (void *__ptr, int __flags);
/* Same as '__lll_robust_lock', but only block until TSP
elapses, using clock CLK. */
extern int __lll_robust_abstimed_lock (void *__ptr,
const struct timespec *__tsp, int __flags, int __clk);
/* Same as '__lll_robust_lock', but return with an error
if the lock cannot be acquired without blocking. */
extern int __lll_robust_trylock (void *__ptr);
/* Wake one or more threads waiting on address PTR,
setting its value to VAL before doing so. */
#define lll_set_wake(ptr, val, flags) \
__gsync_wake (__mach_task_self (), \
(vm_offset_t)ptr, val, flags | GSYNC_MUTATE)
/* Release the robust lock at PTR. */
extern void __lll_robust_unlock (void *__ptr, int __flags);
/* Rearrange threads waiting on address SRC to instead wait on
DST, waking one of them if WAIT_ONE is non-zero. */
#define lll_requeue(src, dst, wake_one, flags) \
__gsync_requeue (__mach_task_self (), (vm_offset_t)src, \
(vm_offset_t)dst, (boolean_t)wake_one, flags)
/* The following are hacks that allow us to simulate optional
parameters in C, to avoid having to pass the clock id for
every one of these calls, defaulting to CLOCK_REALTIME if
no argument is passed. */
#define lll_abstimed_wait(ptr, val, tsp, flags, ...) \
({ \
const clockid_t __clk[] = { CLOCK_REALTIME, ##__VA_ARGS__ }; \
__lll_abstimed_wait ((ptr), (val), (tsp), (flags), \
__clk[sizeof (__clk) / sizeof (__clk[0]) - 1]); \
})
#define lll_abstimed_xwait(ptr, lo, hi, tsp, flags, ...) \
({ \
const clockid_t __clk[] = { CLOCK_REALTIME, ##__VA_ARGS__ }; \
__lll_abstimed_xwait ((ptr), (lo), (hi), (tsp), (flags), \
__clk[sizeof (__clk) / sizeof (__clk[0]) - 1]); \
})
#define lll_abstimed_lock(ptr, tsp, flags, ...) \
({ \
const clockid_t __clk[] = { CLOCK_REALTIME, ##__VA_ARGS__ }; \
__lll_abstimed_lock ((ptr), (tsp), (flags), \
__clk[sizeof (__clk) / sizeof (__clk[0]) - 1]); \
})
#define lll_robust_abstimed_lock(ptr, tsp, flags, ...) \
({ \
const clockid_t __clk[] = { CLOCK_REALTIME, ##__VA_ARGS__ }; \
__lll_robust_abstimed_lock ((ptr), (tsp), (flags), \
__clk[sizeof (__clk) / sizeof (__clk[0]) - 1]); \
})
#endif