#ifndef _LOWLEVELLOCK_FUTEX_H
#define _LOWLEVELLOCK_FUTEX_H 1
-#include <errno.h>
-
-
-/* Values for 'private' parameter of locking macros. Note pthreadP.h
- optimizes for these exact values, though they are not required. */
-#define LLL_PRIVATE 0
-#define LLL_SHARED 128
-
+#ifndef __ASSEMBLER__
+# include <sysdep.h>
+# include <sysdep-cancel.h>
+# include <kernel-features.h>
+#endif
+
+#define FUTEX_WAIT 0
+#define FUTEX_WAKE 1
+#define FUTEX_REQUEUE 3
+#define FUTEX_CMP_REQUEUE 4
+#define FUTEX_WAKE_OP 5
+#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE ((4 << 24) | 1)
+#define FUTEX_LOCK_PI 6
+#define FUTEX_UNLOCK_PI 7
+#define FUTEX_TRYLOCK_PI 8
+#define FUTEX_WAIT_BITSET 9
+#define FUTEX_WAKE_BITSET 10
+#define FUTEX_WAIT_REQUEUE_PI 11
+#define FUTEX_CMP_REQUEUE_PI 12
+#define FUTEX_PRIVATE_FLAG 128
+#define FUTEX_CLOCK_REALTIME 256
+
+#define FUTEX_BITSET_MATCH_ANY 0xffffffff
+
+/* Values for 'private' parameter of locking macros. Yes, the
+ definition seems to be backwards. But it is not. The bit will be
+ reversed before passing to the system call. */
+#define LLL_PRIVATE 0
+#define LLL_SHARED FUTEX_PRIVATE_FLAG
+
+#ifndef __ASSEMBLER__
+
+# if IS_IN (libc) || IS_IN (rtld)
+/* In libc.so or ld.so all futexes are private. */
+# define __lll_private_flag(fl, private) \
+ ({ \
+ /* Prevent warnings in callers of this macro. */ \
+ int __lll_private_flag_priv __attribute__ ((unused)); \
+ __lll_private_flag_priv = (private); \
+ ((fl) | FUTEX_PRIVATE_FLAG); \
+ })
+# else
+# define __lll_private_flag(fl, private) \
+ (((fl) | FUTEX_PRIVATE_FLAG) ^ (private))
+# endif
+
+# define lll_futex_syscall(nargs, futexp, op, ...) \
+ ({ \
+ INTERNAL_SYSCALL_DECL (__err); \
+ long int __ret = INTERNAL_SYSCALL (futex, __err, nargs, futexp, op, \
+ __VA_ARGS__); \
+ (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (__ret, __err)) \
+ ? -INTERNAL_SYSCALL_ERRNO (__ret, __err) : 0); \
+ })
/* For most of these macros, the return value is never really used.
Nevertheless, the protocol is that each one returns a negated errno
/* Wait while *FUTEXP == VAL for an lll_futex_wake call on FUTEXP. */
-#define lll_futex_wait(futexp, val, private) \
+# define lll_futex_wait(futexp, val, private) \
lll_futex_timed_wait (futexp, val, NULL, private)
-/* Wait until a lll_futex_wake call on FUTEXP, or TIMEOUT elapses. */
-#define lll_futex_timed_wait(futexp, val, timeout, private) \
- -ENOSYS
+# define lll_futex_timed_wait(futexp, val, timeout, private) \
+ lll_futex_syscall (4, futexp, \
+ __lll_private_flag (FUTEX_WAIT, private), \
+ val, timeout)
/* Verify whether the supplied clockid is supported by
lll_futex_clock_wait_bitset. */
-#define lll_futex_supported_clockid(clockid) \
- (0)
-
-/* Wait until a lll_futex_wake call on FUTEXP, or the absolute TIMEOUT
- measured against CLOCKID elapses. CLOCKID may be CLOCK_REALTIME or
- CLOCK_MONOTONIC. */
-#define lll_futex_clock_wait_bitset(futexp, val, clockid, timeout, private) \
- -ENOSYS
+# define lll_futex_supported_clockid(clockid) \
+ ((clockid) == CLOCK_REALTIME || (clockid) == CLOCK_MONOTONIC)
+
+/* The kernel currently only supports CLOCK_MONOTONIC or
+ CLOCK_REALTIME timeouts for FUTEX_WAIT_BITSET. We could attempt to
+ convert others here but currently do not. */
+# define lll_futex_clock_wait_bitset(futexp, val, clockid, timeout, private) \
+ ({ \
+ long int __ret; \
+ if (lll_futex_supported_clockid (clockid)) \
+ { \
+ const unsigned int clockbit = \
+ (clockid == CLOCK_REALTIME) ? FUTEX_CLOCK_REALTIME : 0; \
+ const int op = \
+ __lll_private_flag (FUTEX_WAIT_BITSET | clockbit, private); \
+ \
+ __ret = lll_futex_syscall (6, futexp, op, val, \
+ timeout, NULL /* Unused. */, \
+ FUTEX_BITSET_MATCH_ANY); \
+ } \
+ else \
+ __ret = -EINVAL; \
+ __ret; \
+ })
/* Wake up up to NR waiters on FUTEXP. */
-#define lll_futex_wake(futexp, nr, private) \
- -ENOSYS
+# define lll_futex_wake(futexp, nr, private) \
+ lll_futex_syscall (4, futexp, \
+ __lll_private_flag (FUTEX_WAKE, private), nr, 0)
/* Wake up up to NR_WAKE waiters on FUTEXP. Move up to NR_MOVE of the
- rest from waiting on FUTEXP to waiting on MUTEX (a different futex). */
-#define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val, private) \
- -ENOSYS
+ rest from waiting on FUTEXP to waiting on MUTEX (a different futex).
+ Returns non-zero if error happened, zero if success. */
+# define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val, private) \
+ lll_futex_syscall (6, futexp, \
+ __lll_private_flag (FUTEX_CMP_REQUEUE, private), \
+ nr_wake, nr_move, mutex, val)
+
+/* Wake up up to NR_WAKE waiters on FUTEXP and NR_WAKE2 on FUTEXP2.
+ Returns non-zero if error happened, zero if success. */
+# define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \
+ lll_futex_syscall (6, futexp, \
+ __lll_private_flag (FUTEX_WAKE_OP, private), \
+ nr_wake, nr_wake2, futexp2, \
+ FUTEX_OP_CLEAR_WAKE_IF_GT_ONE)
-/* Wake up up to NR_WAKE waiters on FUTEXP and NR_WAKE2 on FUTEXP2. */
-#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \
- -ENOSYS
+/* Priority Inheritance support. */
/* Like lll_futex_wait (FUTEXP, VAL, PRIVATE) but with the expectation
that lll_futex_cmp_requeue_pi (FUTEXP, _, _, MUTEX, _, PRIVATE) will
be used to do the wakeup. Confers priority-inheritance behavior on
the waiter. */
-#define lll_futex_wait_requeue_pi(futexp, val, mutex, private) \
+# define lll_futex_wait_requeue_pi(futexp, val, mutex, private) \
lll_futex_timed_wait_requeue_pi (futexp, val, NULL, 0, mutex, private)
/* Like lll_futex_wait_requeue_pi, but with a timeout. */
-#define lll_futex_timed_wait_requeue_pi(futexp, val, timeout, clockbit, \
+# define lll_futex_timed_wait_requeue_pi(futexp, val, timeout, clockbit, \
mutex, private) \
- -ENOSYS
+ lll_futex_syscall (5, futexp, \
+ __lll_private_flag (FUTEX_WAIT_REQUEUE_PI \
+ | (clockbit), private), \
+ val, timeout, mutex)
/* Like lll_futex_requeue, but pairs with lll_futex_wait_requeue_pi
and inherits priority from the waiter. */
-#define lll_futex_cmp_requeue_pi(futexp, nr_wake, nr_move, mutex, \
+# define lll_futex_cmp_requeue_pi(futexp, nr_wake, nr_move, mutex, \
val, private) \
- -ENOSYS
+ lll_futex_syscall (6, futexp, \
+ __lll_private_flag (FUTEX_CMP_REQUEUE_PI, \
+ private), \
+ nr_wake, nr_move, mutex, val)
/* Like lll_futex_wait, but acting as a cancellable entrypoint. */
-#define lll_futex_wait_cancel(futexp, val, private) \
- -ENOSYS
+# define lll_futex_wait_cancel(futexp, val, private) \
+ ({ \
+ int __oldtype = CANCEL_ASYNC (); \
+ long int __err = lll_futex_wait (futexp, val, LLL_SHARED); \
+ CANCEL_RESET (__oldtype); \
+ __err; \
+ })
/* Like lll_futex_timed_wait, but acting as a cancellable entrypoint. */
-#define lll_futex_timed_wait_cancel(futexp, val, timeout, private) \
- -ENOSYS
+# define lll_futex_timed_wait_cancel(futexp, val, timeout, private) \
+ ({ \
+ int __oldtype = CANCEL_ASYNC (); \
+ long int __err = lll_futex_timed_wait (futexp, val, timeout, private); \
+ CANCEL_RESET (__oldtype); \
+ __err; \
+ })
+
+#endif /* !__ASSEMBLER__ */
#endif /* lowlevellock-futex.h */
+++ /dev/null
-/* Low-level locking access to futex facilities. Linux version.
- Copyright (C) 2005-2019 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
- <https://www.gnu.org/licenses/>. */
-
-#ifndef _LOWLEVELLOCK_FUTEX_H
-#define _LOWLEVELLOCK_FUTEX_H 1
-
-#ifndef __ASSEMBLER__
-#include <sysdep.h>
-#include <sysdep-cancel.h>
-#include <kernel-features.h>
-#endif
-
-#define FUTEX_WAIT 0
-#define FUTEX_WAKE 1
-#define FUTEX_REQUEUE 3
-#define FUTEX_CMP_REQUEUE 4
-#define FUTEX_WAKE_OP 5
-#define FUTEX_OP_CLEAR_WAKE_IF_GT_ONE ((4 << 24) | 1)
-#define FUTEX_LOCK_PI 6
-#define FUTEX_UNLOCK_PI 7
-#define FUTEX_TRYLOCK_PI 8
-#define FUTEX_WAIT_BITSET 9
-#define FUTEX_WAKE_BITSET 10
-#define FUTEX_WAIT_REQUEUE_PI 11
-#define FUTEX_CMP_REQUEUE_PI 12
-#define FUTEX_PRIVATE_FLAG 128
-#define FUTEX_CLOCK_REALTIME 256
-
-#define FUTEX_BITSET_MATCH_ANY 0xffffffff
-
-/* Values for 'private' parameter of locking macros. Yes, the
- definition seems to be backwards. But it is not. The bit will be
- reversed before passing to the system call. */
-#define LLL_PRIVATE 0
-#define LLL_SHARED FUTEX_PRIVATE_FLAG
-
-#ifndef __ASSEMBLER__
-
-#if IS_IN (libc) || IS_IN (rtld)
-/* In libc.so or ld.so all futexes are private. */
-# define __lll_private_flag(fl, private) \
- ({ \
- /* Prevent warnings in callers of this macro. */ \
- int __lll_private_flag_priv __attribute__ ((unused)); \
- __lll_private_flag_priv = (private); \
- ((fl) | FUTEX_PRIVATE_FLAG); \
- })
-#else
-# define __lll_private_flag(fl, private) \
- (((fl) | FUTEX_PRIVATE_FLAG) ^ (private))
-#endif
-
-#define lll_futex_syscall(nargs, futexp, op, ...) \
- ({ \
- INTERNAL_SYSCALL_DECL (__err); \
- long int __ret = INTERNAL_SYSCALL (futex, __err, nargs, futexp, op, \
- __VA_ARGS__); \
- (__glibc_unlikely (INTERNAL_SYSCALL_ERROR_P (__ret, __err)) \
- ? -INTERNAL_SYSCALL_ERRNO (__ret, __err) : 0); \
- })
-
-#define lll_futex_wait(futexp, val, private) \
- lll_futex_timed_wait (futexp, val, NULL, private)
-
-#define lll_futex_timed_wait(futexp, val, timeout, private) \
- lll_futex_syscall (4, futexp, \
- __lll_private_flag (FUTEX_WAIT, private), \
- val, timeout)
-
-/* Verify whether the supplied clockid is supported by
- lll_futex_clock_wait_bitset. */
-#define lll_futex_supported_clockid(clockid) \
- ((clockid) == CLOCK_REALTIME || (clockid) == CLOCK_MONOTONIC)
-
-/* The kernel currently only supports CLOCK_MONOTONIC or
- CLOCK_REALTIME timeouts for FUTEX_WAIT_BITSET. We could attempt to
- convert others here but currently do not. */
-#define lll_futex_clock_wait_bitset(futexp, val, clockid, timeout, private) \
- ({ \
- long int __ret; \
- if (lll_futex_supported_clockid (clockid)) \
- { \
- const unsigned int clockbit = \
- (clockid == CLOCK_REALTIME) ? FUTEX_CLOCK_REALTIME : 0; \
- const int op = \
- __lll_private_flag (FUTEX_WAIT_BITSET | clockbit, private); \
- \
- __ret = lll_futex_syscall (6, futexp, op, val, \
- timeout, NULL /* Unused. */, \
- FUTEX_BITSET_MATCH_ANY); \
- } \
- else \
- __ret = -EINVAL; \
- __ret; \
- })
-
-#define lll_futex_wake(futexp, nr, private) \
- lll_futex_syscall (4, futexp, \
- __lll_private_flag (FUTEX_WAKE, private), nr, 0)
-
-/* Returns non-zero if error happened, zero if success. */
-#define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val, private) \
- lll_futex_syscall (6, futexp, \
- __lll_private_flag (FUTEX_CMP_REQUEUE, private), \
- nr_wake, nr_move, mutex, val)
-
-/* Returns non-zero if error happened, zero if success. */
-#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2, private) \
- lll_futex_syscall (6, futexp, \
- __lll_private_flag (FUTEX_WAKE_OP, private), \
- nr_wake, nr_wake2, futexp2, \
- FUTEX_OP_CLEAR_WAKE_IF_GT_ONE)
-
-/* Priority Inheritance support. */
-#define lll_futex_wait_requeue_pi(futexp, val, mutex, private) \
- lll_futex_timed_wait_requeue_pi (futexp, val, NULL, 0, mutex, private)
-
-#define lll_futex_timed_wait_requeue_pi(futexp, val, timeout, clockbit, \
- mutex, private) \
- lll_futex_syscall (5, futexp, \
- __lll_private_flag (FUTEX_WAIT_REQUEUE_PI \
- | (clockbit), private), \
- val, timeout, mutex)
-
-
-#define lll_futex_cmp_requeue_pi(futexp, nr_wake, nr_move, mutex, \
- val, private) \
- lll_futex_syscall (6, futexp, \
- __lll_private_flag (FUTEX_CMP_REQUEUE_PI, \
- private), \
- nr_wake, nr_move, mutex, val)
-
-
-/* Cancellable futex macros. */
-#define lll_futex_wait_cancel(futexp, val, private) \
- ({ \
- int __oldtype = CANCEL_ASYNC (); \
- long int __err = lll_futex_wait (futexp, val, LLL_SHARED); \
- CANCEL_RESET (__oldtype); \
- __err; \
- })
-
-#define lll_futex_timed_wait_cancel(futexp, val, timeout, private) \
- ({ \
- int __oldtype = CANCEL_ASYNC (); \
- long int __err = lll_futex_timed_wait (futexp, val, timeout, private); \
- CANCEL_RESET (__oldtype); \
- __err; \
- })
-
-#endif /* !__ASSEMBLER__ */
-
-#endif /* lowlevellock-futex.h */
git://sourceware.org / glibc.git / commitdiff