aboutsummaryrefslogtreecommitdiff
path: root/linuxthreads/sysdeps/x86_64/pspinlock.c
diff options
context:
space:
mode:
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)