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Diffstat (limited to 'linuxthreads/sysdeps/x86_64/pspinlock.c')
-rw-r--r--linuxthreads/sysdeps/x86_64/pspinlock.c97
1 files changed, 0 insertions, 97 deletions
diff --git a/linuxthreads/sysdeps/x86_64/pspinlock.c b/linuxthreads/sysdeps/x86_64/pspinlock.c
deleted file mode 100644
index e1b2a66841..0000000000
--- a/linuxthreads/sysdeps/x86_64/pspinlock.c
+++ /dev/null
@@ -1,97 +0,0 @@
-/* POSIX spinlock implementation.  x86-64 version.
-   Copyright (C) 2001 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, write to the Free
-   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
-   02111-1307 USA.  */
-
-#include <errno.h>
-#include <pthread.h>
-#include "internals.h"
-
-/* This implementation is similar to the one used in the Linux kernel.
-   But the kernel is byte instructions for the memory access.  This is
-   faster but unusable here.  The problem is that only 128
-   threads/processes could use the spinlock at the same time.  If (by
-   a design error in the program) a thread/process would hold the
-   spinlock for a time long enough to accumulate 128 waiting
-   processes, the next one will find a positive value in the spinlock
-   and assume it is unlocked.  We cannot accept that.  */
-
-int
-__pthread_spin_lock (pthread_spinlock_t *lock)
-{
-  asm volatile
-    ("\n"
-     "1:\n\t"
-     "lock; decl %0\n\t"
-     "js 2f\n\t"
-     ".section .text.spinlock,\"ax\"\n"
-     "2:\n\t"
-     "cmpl $0,%0\n\t"
-     "rep; nop\n\t"
-     "jle 2b\n\t"
-     "jmp 1b\n\t"
-     ".previous"
-     : "=m" (*lock));
-  return 0;
-}
-weak_alias (__pthread_spin_lock, pthread_spin_lock)
-
-
-int
-__pthread_spin_trylock (pthread_spinlock_t *lock)
-{
-  int oldval;
-
-  asm volatile
-    ("xchgl %0,%1"
-     : "=r" (oldval), "=m" (*lock)
-     : "0" (0));
-  return oldval > 0 ? 0 : EBUSY;
-}
-weak_alias (__pthread_spin_trylock, pthread_spin_trylock)
-
-
-int
-__pthread_spin_unlock (pthread_spinlock_t *lock)
-{
-  asm volatile
-    ("movl $1,%0"
-     : "=m" (*lock));
-  return 0;
-}
-weak_alias (__pthread_spin_unlock, pthread_spin_unlock)
-
-
-int
-__pthread_spin_init (pthread_spinlock_t *lock, int pshared)
-{
-  /* We can ignore the `pshared' parameter.  Since we are busy-waiting
-     all processes which can access the memory location `lock' points
-     to can use the spinlock.  */
-  *lock = 1;
-  return 0;
-}
-weak_alias (__pthread_spin_init, pthread_spin_init)
-
-
-int
-__pthread_spin_destroy (pthread_spinlock_t *lock)
-{
-  /* Nothing to do.  */
-  return 0;
-}
-weak_alias (__pthread_spin_destroy, pthread_spin_destroy)