libpthread/nptl: core of the "Native Posix Threading Library" for uClibc

targetting arm,sh,i386,mips,sparc for now

Signed-off-by: Austin Foxley <austinf@cetoncorp.com>

1 files changed, 340 insertions, 0 deletions

diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/arm/lowlevellock.h b/libpthread/nptl/sysdeps/unix/sysv/linux/arm/lowlevellock.h
new file mode 100644
index 000000000..df5833c46
--- /dev/null
+++ b/libpthread/nptl/sysdeps/unix/sysv/linux/arm/lowlevellock.h
@@ -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 */
+