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authorWaldemar Brodkorb <wbx@openadk.org>2015-02-14 23:00:19 -0600
committerWaldemar Brodkorb <wbx@openadk.org>2015-02-14 23:00:19 -0600
commit6b6ede3d15f04fe825cfa9f697507457e3640344 (patch)
treeefe9bf75eaf2200f89087ed0ef2ef350549ccd6d /libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c
parentf972c2262fd4efc2bbf9789dce145bb705acec24 (diff)
resolve merge
Diffstat (limited to 'libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c')
-rw-r--r--libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c96
1 files changed, 0 insertions, 96 deletions
diff --git a/libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c b/libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c
deleted file mode 100644
index 80c1b05a8..000000000
--- a/libpthread/linuxthreads/sysdeps/x86_64/pspinlock.c
+++ /dev/null
@@ -1,96 +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, see
- <http://www.gnu.org/licenses/>. */
-
-#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)