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diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/arm/lowlevellock.h b/libpthread/nptl/sysdeps/unix/sysv/linux/arm/lowlevellock.h
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@@ -0,0 +1,340 @@
+/* Copyright (C) 2005, 2006 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 Libr \ary; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#ifndef _LOWLEVELLOCK_H
+#define _LOWLEVELLOCK_H 1
+
+#include <time.h>
+#include <sys/param.h>
+#include <bits/pthreadtypes.h>
+#include <atomic.h>
+#include <sysdep.h>
+
+#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)
+
+/* Initializer for compatibility lock. */
+#define LLL_MUTEX_LOCK_INITIALIZER (0)
+
+#define lll_futex_wait(futexp, val) \
+ ({ \
+ INTERNAL_SYSCALL_DECL (__err); \
+ long int __ret; \
+ __ret = INTERNAL_SYSCALL (futex, __err, 4, \
+ (futexp), FUTEX_WAIT, (val), 0); \
+ __ret; \
+ })
+
+#define lll_futex_timed_wait(futexp, val, timespec) \
+ ({ \
+ INTERNAL_SYSCALL_DECL (__err); \
+ long int __ret; \
+ __ret = INTERNAL_SYSCALL (futex, __err, 4, \
+ (futexp), FUTEX_WAIT, (val), (timespec)); \
+ __ret; \
+ })
+
+#define lll_futex_wake(futexp, nr) \
+ ({ \
+ INTERNAL_SYSCALL_DECL (__err); \
+ long int __ret; \
+ __ret = INTERNAL_SYSCALL (futex, __err, 4, \
+ (futexp), FUTEX_WAKE, (nr), 0); \
+ __ret; \
+ })
+
+#define lll_robust_mutex_dead(futexv) \
+ do \
+ { \
+ int *__futexp = &(futexv); \
+ atomic_or (__futexp, FUTEX_OWNER_DIED); \
+ lll_futex_wake (__futexp, 1); \
+ } \
+ while (0)
+
+/* Returns non-zero if error happened, zero if success. */
+#define lll_futex_requeue(futexp, nr_wake, nr_move, mutex, val) \
+ ({ \
+ INTERNAL_SYSCALL_DECL (__err); \
+ long int __ret; \
+ __ret = INTERNAL_SYSCALL (futex, __err, 6, \
+ (futexp), FUTEX_CMP_REQUEUE, (nr_wake), \
+ (nr_move), (mutex), (val)); \
+ __ret; \
+ })
+
+
+/* Returns non-zero if error happened, zero if success. */
+#define lll_futex_wake_unlock(futexp, nr_wake, nr_wake2, futexp2) \
+ ({ \
+ INTERNAL_SYSCALL_DECL (__err); \
+ long int __ret; \
+ __ret = INTERNAL_SYSCALL (futex, __err, 6, \
+ (futexp), FUTEX_WAKE_OP, (nr_wake), \
+ (nr_wake2), (futexp2), \
+ FUTEX_OP_CLEAR_WAKE_IF_GT_ONE); \
+ __ret; \
+ })
+
+
+static inline int __attribute__((always_inline))
+__lll_mutex_trylock (int *futex)
+{
+ int flag = 1, old;
+#ifdef __thumb__
+ old = atomic_exchange_acq (futex, flag);
+ if (old < 1)
+ flag = 0;
+ else if (old > 1)
+ flag = atomic_exchange_acq (futex, old);
+#else
+ __asm__ __volatile__ (
+ "\tswp %[old], %[flag], [%[futex]] @ try to take the lock\n"
+ "\tcmp %[old], #1 @ check old lock value\n"
+ "\tmovlo %[flag], #0 @ if we got it, return 0\n"
+ "\tswphi %[flag], %[old], [%[futex]] @ if it was contested,\n"
+ " @ restore the contested flag,\n"
+ " @ and check whether that won."
+ : [futex] "+&r" (futex), [flag] "+&r" (flag), [old] "=&r" (old)
+ : : "memory" );
+#endif
+
+ return flag;
+}
+#define lll_mutex_trylock(lock) __lll_mutex_trylock (&(lock))
+
+
+static inline int __attribute__((always_inline))
+__lll_mutex_cond_trylock (int *futex)
+{
+ int flag = 2, old;
+#ifdef __thumb__
+ old = atomic_exchange_acq (futex, flag);
+ if (old < 1)
+ flag = 0;
+ else if (old > 1)
+ flag = atomic_exchange_acq (futex, old);
+#else
+ __asm__ __volatile__ (
+ "\tswp %[old], %[flag], [%[futex]] @ try to take the lock\n"
+ "\tcmp %[old], #1 @ check old lock value\n"
+ "\tmovlo %[flag], #0 @ if we got it, return 0\n"
+ "\tswphi %[flag], %[old], [%[futex]] @ if it was contested,\n"
+ " @ restore the contested flag,\n"
+ " @ and check whether that won."
+ : [futex] "+&r" (futex), [flag] "+&r" (flag), [old] "=&r" (old)
+ : : "memory" );
+#endif
+
+ return flag;
+}
+#define lll_mutex_cond_trylock(lock) __lll_mutex_cond_trylock (&(lock))
+
+
+static inline int __attribute__((always_inline))
+__lll_robust_mutex_trylock(int *futex, int id)
+{
+ return atomic_compare_and_exchange_val_acq (futex, id, 0) != 0;
+}
+#define lll_robust_mutex_trylock(lock, id) \
+ __lll_robust_mutex_trylock (&(lock), id)
+
+extern int __lll_robust_lock_wait (int *futex) attribute_hidden;
+
+static inline void __attribute__((always_inline))
+__lll_mutex_lock (int *futex)
+{
+ int val = atomic_exchange_acq (futex, 1);
+
+ if (__builtin_expect (val != 0, 0))
+ {
+ while (atomic_exchange_acq (futex, 2) != 0)
+ lll_futex_wait (futex, 2);
+ }
+}
+#define lll_mutex_lock(futex) __lll_mutex_lock (&(futex))
+
+
+static inline int __attribute__ ((always_inline))
+__lll_robust_mutex_lock (int *futex, int id)
+{
+ int result = 0;
+ if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0)
+ result = __lll_robust_lock_wait (futex);
+ return result;
+}
+#define lll_robust_mutex_lock(futex, id) \
+ __lll_robust_mutex_lock (&(futex), id)
+
+
+static inline void __attribute__ ((always_inline))
+__lll_mutex_cond_lock (int *futex)
+{
+ int val = atomic_exchange_acq (futex, 2);
+
+ if (__builtin_expect (val != 0, 0))
+ {
+ while (atomic_exchange_acq (futex, 2) != 0)
+ lll_futex_wait (futex, 2);
+ }
+}
+#define lll_mutex_cond_lock(futex) __lll_mutex_cond_lock (&(futex))
+
+
+#define lll_robust_mutex_cond_lock(futex, id) \
+ __lll_robust_mutex_lock (&(futex), (id) | FUTEX_WAITERS)
+
+
+extern int __lll_timedlock_wait (int *futex, const struct timespec *)
+ attribute_hidden;
+extern int __lll_robust_timedlock_wait (int *futex, const struct timespec *)
+ attribute_hidden;
+
+static inline int __attribute__ ((always_inline))
+__lll_mutex_timedlock (int *futex, const struct timespec *abstime)
+{
+ int result = 0;
+ int val = atomic_exchange_acq (futex, 1);
+
+ if (__builtin_expect (val != 0, 0))
+ result = __lll_timedlock_wait (futex, abstime);
+ return result;
+}
+#define lll_mutex_timedlock(futex, abstime) \
+ __lll_mutex_timedlock (&(futex), abstime)
+
+
+static inline int __attribute__ ((always_inline))
+__lll_robust_mutex_timedlock (int *futex, const struct timespec *abstime,
+ int id)
+{
+ int result = 0;
+ if (atomic_compare_and_exchange_bool_acq (futex, id, 0) != 0)
+ result = __lll_robust_timedlock_wait (futex, abstime);
+ return result;
+}
+#define lll_robust_mutex_timedlock(futex, abstime, id) \
+ __lll_robust_mutex_timedlock (&(futex), abstime, id)
+
+
+static inline void __attribute__ ((always_inline))
+__lll_mutex_unlock (int *futex)
+{
+ int val = atomic_exchange_rel (futex, 0);
+ if (__builtin_expect (val > 1, 0))
+ lll_futex_wake (futex, 1);
+}
+#define lll_mutex_unlock(futex) __lll_mutex_unlock(&(futex))
+
+
+static inline void __attribute__ ((always_inline))
+__lll_robust_mutex_unlock (int *futex, int mask)
+{
+ int val = atomic_exchange_rel (futex, 0);
+ if (__builtin_expect (val & mask, 0))
+ lll_futex_wake (futex, 1);
+}
+#define lll_robust_mutex_unlock(futex) \
+ __lll_robust_mutex_unlock(&(futex), FUTEX_WAITERS)
+
+
+static inline void __attribute__ ((always_inline))
+__lll_mutex_unlock_force (int *futex)
+{
+ (void) atomic_exchange_rel (futex, 0);
+ lll_futex_wake (futex, 1);
+}
+#define lll_mutex_unlock_force(futex) __lll_mutex_unlock_force(&(futex))
+
+
+#define lll_mutex_islocked(futex) \
+ (futex != 0)
+
+
+/* Our internal lock implementation is identical to the binary-compatible
+ mutex implementation. */
+
+/* Type for lock object. */
+typedef int lll_lock_t;
+
+/* Initializers for lock. */
+#define LLL_LOCK_INITIALIZER (0)
+#define LLL_LOCK_INITIALIZER_LOCKED (1)
+
+extern int lll_unlock_wake_cb (int *__futex) attribute_hidden;
+
+/* The states of a lock are:
+ 0 - untaken
+ 1 - taken by one user
+ >1 - taken by more users */
+
+#define lll_trylock(lock) lll_mutex_trylock (lock)
+#define lll_lock(lock) lll_mutex_lock (lock)
+#define lll_unlock(lock) lll_mutex_unlock (lock)
+#define lll_islocked(lock) lll_mutex_islocked (lock)
+
+/* The kernel notifies a process which uses CLONE_CLEARTID via futex
+ wakeup when the clone terminates. The memory location contains the
+ thread ID while the clone is running and is reset to zero
+ afterwards. */
+#define lll_wait_tid(tid) \
+ do { \
+ __typeof (tid) __tid; \
+ while ((__tid = (tid)) != 0) \
+ lll_futex_wait (&(tid), __tid); \
+ } while (0)
+
+extern int __lll_timedwait_tid (int *, const struct timespec *)
+ attribute_hidden;
+
+#define lll_timedwait_tid(tid, abstime) \
+ ({ \
+ int __res = 0; \
+ if ((tid) != 0) \
+ __res = __lll_timedwait_tid (&(tid), (abstime)); \
+ __res; \
+ })
+
+
+/* Conditional variable handling. */
+
+extern void __lll_cond_wait (pthread_cond_t *cond)
+ attribute_hidden;
+extern int __lll_cond_timedwait (pthread_cond_t *cond,
+ const struct timespec *abstime)
+ attribute_hidden;
+extern void __lll_cond_wake (pthread_cond_t *cond)
+ attribute_hidden;
+extern void __lll_cond_broadcast (pthread_cond_t *cond)
+ attribute_hidden;
+
+#define lll_cond_wait(cond) \
+ __lll_cond_wait (cond)
+#define lll_cond_timedwait(cond, abstime) \
+ __lll_cond_timedwait (cond, abstime)
+#define lll_cond_wake(cond) \
+ __lll_cond_wake (cond)
+#define lll_cond_broadcast(cond) \
+ __lll_cond_broadcast (cond)
+
+#endif /* lowlevellock.h */
+
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