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-rw-r--r--libpthread/linuxthreads/spinlock.h102
1 files changed, 102 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/spinlock.h b/libpthread/linuxthreads/spinlock.h
new file mode 100644
index 000000000..aae18a27b
--- /dev/null
+++ b/libpthread/linuxthreads/spinlock.h
@@ -0,0 +1,102 @@
+/* Linuxthreads - a simple clone()-based implementation of Posix */
+/* threads for Linux. */
+/* Copyright (C) 1998 Xavier Leroy (Xavier.Leroy@inria.fr) */
+/* */
+/* This program 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. */
+/* */
+/* This program 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. */
+
+#if defined(TEST_FOR_COMPARE_AND_SWAP)
+
+extern int __pthread_has_cas;
+extern int __pthread_compare_and_swap(long * ptr, long oldval, long newval,
+ int * spinlock);
+
+static inline int compare_and_swap(long * ptr, long oldval, long newval,
+ int * spinlock)
+{
+ if (__builtin_expect (__pthread_has_cas, 1))
+ return __compare_and_swap(ptr, oldval, newval);
+ else
+ return __pthread_compare_and_swap(ptr, oldval, newval, spinlock);
+}
+
+#elif defined(HAS_COMPARE_AND_SWAP)
+
+static inline int compare_and_swap(long * ptr, long oldval, long newval,
+ int * spinlock)
+{
+ return __compare_and_swap(ptr, oldval, newval);
+}
+
+#else
+
+extern int __pthread_compare_and_swap(long * ptr, long oldval, long newval,
+ int * spinlock);
+
+static inline int compare_and_swap(long * ptr, long oldval, long newval,
+ int * spinlock)
+{
+ return __pthread_compare_and_swap(ptr, oldval, newval, spinlock);
+}
+
+#endif
+
+/* Internal locks */
+
+extern void internal_function __pthread_lock(struct _pthread_fastlock * lock,
+ pthread_descr self);
+extern void internal_function __pthread_unlock(struct _pthread_fastlock *lock);
+
+static inline void __pthread_init_lock(struct _pthread_fastlock * lock)
+{
+ lock->__status = 0;
+ lock->__spinlock = 0;
+}
+
+static inline int __pthread_trylock (struct _pthread_fastlock * lock)
+{
+ long oldstatus;
+
+ do {
+ oldstatus = lock->__status;
+ if (oldstatus != 0) return EBUSY;
+ } while(! compare_and_swap(&lock->__status, 0, 1, &lock->__spinlock));
+ return 0;
+}
+
+#define LOCK_INITIALIZER {0, 0}
+
+/* Operations on pthread_atomic, which is defined in internals.h */
+
+static inline long atomic_increment(struct pthread_atomic *pa)
+{
+ long oldval;
+
+ do {
+ oldval = pa->p_count;
+ } while (!compare_and_swap(&pa->p_count, oldval, oldval + 1, &pa->p_spinlock));
+
+ return oldval;
+}
+
+
+static inline long atomic_decrement(struct pthread_atomic *pa)
+{
+ long oldval;
+
+ do {
+ oldval = pa->p_count;
+ } while (!compare_and_swap(&pa->p_count, oldval, oldval - 1, &pa->p_spinlock));
+
+ return oldval;
+}
+
+#define ATOMIC_INITIALIZER { 0, 0 }
+