diff options
Diffstat (limited to 'linuxthreads/sysdeps')
-rw-r--r-- | linuxthreads/sysdeps/ia64/pspinlock.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/linuxthreads/sysdeps/ia64/pspinlock.c b/linuxthreads/sysdeps/ia64/pspinlock.c new file mode 100644 index 0000000000..ada28bd9f0 --- /dev/null +++ b/linuxthreads/sysdeps/ia64/pspinlock.c @@ -0,0 +1,93 @@ +/* POSIX spinlock implementation. ia64 version. + Copyright (C) 2000 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Jes Sorensen <jes@linuxcare.com> + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. 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> + + +/* This implementation is inspired by the implementation used in the + Linux kernel. */ + +int +__pthread_spin_lock (pthread_spinlock_t *lock) +{ + asm volatile + ("mov ar.ccv = r0\n\t" + "mov r3 = 1\n\t" + ";;\n" + "1:\n\t" + "ld4 r2 = %0\n\t" + ";;\n\t" + "cmp4.eq p0, p7 = r0, r2\n\t" + "(p7) br.cond.spnt.few 1b \n\t" + "cmpxchg4.acq r2 = %0, r3, ar.ccv\n\t" + ";;\n\t" + "cmp4.eq p0, p7 = r0, r2\n\t" + "(p7) br.cond.spnt.few 1b\n\t" + ";;\n" + :: "m" (lock) : "r2", "r3", "p7", "memory"); + return 0; +} +weak_alias (__pthread_spin_lock, pthread_spin_lock) + + +int +__pthread_spin_trylock (pthread_spinlock_t *lock) +{ + int oldval; + + asm volatile + ("mov ar.ccv = r0\n\t" + "mov r2 = 1\n\t" + ";;\n\t" + "cmpxchg4.acq %0 = %1, r2, ar.ccv\n\t" + ";;\n" + : "=r" (oldval) : "m" (lock) : "r2", "memory"); + return oldval > 0 ? 0 : EBUSY; +} +weak_alias (__pthread_spin_trylock, pthread_spin_trylock) + + +int +__pthread_spin_unlock (pthread_spinlock_t *lock) +{ + return *lock = 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. */ + return *lock = 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) |