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Diffstat (limited to 'linuxthreads/sysdeps/sparc/sparc64/pspinlock.c')
-rw-r--r--linuxthreads/sysdeps/sparc/sparc64/pspinlock.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/linuxthreads/sysdeps/sparc/sparc64/pspinlock.c b/linuxthreads/sysdeps/sparc/sparc64/pspinlock.c
new file mode 100644
index 0000000000..92b84f5108
--- /dev/null
+++ b/linuxthreads/sysdeps/sparc/sparc64/pspinlock.c
@@ -0,0 +1,93 @@
+/* POSIX spinlock implementation.  SPARC64 version.
+   Copyright (C) 2000 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; 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>
+#include "internals.h"
+
+/* This implementation is similar to the one used in the Linux kernel.  */
+int
+__pthread_spin_lock (pthread_spinlock_t *lock)
+{
+  asm volatile
+    ("1: ldstub  [%0], %%g5\n"
+     "   brnz,pn %%g5, 2f\n"
+     "    membar #StoreLoad | #StoreStore\n"
+     ".subsection 2\n"
+     "2: ldub    [%0], %%g5\n"
+     "   brnz,pt %%g5, 2b\n"
+     "    membar #LoadLoad\n"
+     "   b,a,pt  %%xcc, 1b\n"
+     ".previous"
+     : /* no outputs */
+     : "r" (lock)
+     : "g5", "memory");
+  return 0;
+}
+weak_alias (__pthread_spin_lock, pthread_spin_lock)
+
+
+int
+__pthread_spin_trylock (pthread_spinlock_t *lock)
+{
+  int result;
+  asm volatile
+    ("ldstub [%1], %0\n"
+     "membar #StoreLoad | #StoreStore"
+     : "=r" (result)
+     : "r" (lock)
+     : "memory");
+  return result == 0 ? 0 : EBUSY;
+}
+weak_alias (__pthread_spin_trylock, pthread_spin_trylock)
+
+
+int
+__pthread_spin_unlock (pthread_spinlock_t *lock)
+{
+  asm volatile
+    ("membar #StoreStore | #LoadStore\n"
+     "stb    %%g0, [%0]"
+     :
+     : "r" (lock)
+     : "memory");
+  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 = 0;
+  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)