The R13B03 release.OTP_R13B03

1 files changed, 81 insertions, 0 deletions

diff --git a/erts/include/internal/sparc32/spinlock.h b/erts/include/internal/sparc32/spinlock.h
new file mode 100644
index 0000000000..b4fe48b714
--- /dev/null
+++ b/erts/include/internal/sparc32/spinlock.h
@@ -0,0 +1,81 @@
+/*
+ * %CopyrightBegin%
+ * 
+ * Copyright Ericsson AB 2005-2009. All Rights Reserved.
+ * 
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ * 
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ * 
+ * %CopyrightEnd%
+ */
+
+/*
+ * Native ethread spinlocks on SPARC V9.
+ * Author: Mikael Pettersson.
+ */
+#ifndef ETHR_SPARC32_SPINLOCK_H
+#define ETHR_SPARC32_SPINLOCK_H
+
+/* Locked with ldstub, so unlocked when 0 and locked when non-zero. */
+typedef struct {
+    volatile unsigned char lock;
+} ethr_native_spinlock_t;
+
+#ifdef ETHR_TRY_INLINE_FUNCS
+
+static ETHR_INLINE void
+ethr_native_spinlock_init(ethr_native_spinlock_t *lock)
+{
+    lock->lock = 0;
+}
+
+static ETHR_INLINE void
+ethr_native_spin_unlock(ethr_native_spinlock_t *lock)
+{
+    __asm__ __volatile__("membar #LoadStore|#StoreStore");
+    lock->lock = 0;
+}
+
+static ETHR_INLINE int
+ethr_native_spin_trylock(ethr_native_spinlock_t *lock)
+{
+    unsigned int prev;
+
+    __asm__ __volatile__(
+	"ldstub [%1], %0\n\t"
+	"membar #StoreLoad|#StoreStore"
+	: "=r"(prev)
+	: "r"(&lock->lock)
+	: "memory");
+    return prev == 0;
+}
+
+static ETHR_INLINE int
+ethr_native_spin_is_locked(ethr_native_spinlock_t *lock)
+{
+    return lock->lock != 0;
+}
+
+static ETHR_INLINE void
+ethr_native_spin_lock(ethr_native_spinlock_t *lock)
+{
+    for(;;) {
+	if (__builtin_expect(ethr_native_spin_trylock(lock) != 0, 1))
+	    break;
+	do {
+	    __asm__ __volatile__("membar #LoadLoad");
+	} while (ethr_native_spin_is_locked(lock));
+    }
+}
+
+#endif /* ETHR_TRY_INLINE_FUNCS */
+
+#endif /* ETHR_SPARC32_SPINLOCK_H */