Adding upstream version 0.6.0.upstream/0.6.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 119 insertions, 0 deletions

diff --git a/include/spinlock/cas.h b/include/spinlock/cas.h
new file mode 100644
index 0000000..ff6d723
--- /dev/null
+++ b/include/spinlock/cas.h
@@ -0,0 +1,119 @@
+/*
+ * Copyright 2010-2015 Samy Al Bahra.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef CK_SPINLOCK_CAS_H
+#define CK_SPINLOCK_CAS_H
+
+#include <ck_backoff.h>
+#include <ck_cc.h>
+#include <ck_elide.h>
+#include <ck_pr.h>
+#include <ck_stdbool.h>
+
+#ifndef CK_F_SPINLOCK_CAS
+#define CK_F_SPINLOCK_CAS
+/*
+ * This is a simple CACAS (TATAS) spinlock implementation.
+ */
+struct ck_spinlock_cas {
+	unsigned int value;
+};
+typedef struct ck_spinlock_cas ck_spinlock_cas_t;
+
+#define CK_SPINLOCK_CAS_INITIALIZER {false}
+
+CK_CC_INLINE static void
+ck_spinlock_cas_init(struct ck_spinlock_cas *lock)
+{
+
+	lock->value = false;
+	ck_pr_barrier();
+	return;
+}
+
+CK_CC_INLINE static bool
+ck_spinlock_cas_trylock(struct ck_spinlock_cas *lock)
+{
+	unsigned int value;
+
+	value = ck_pr_fas_uint(&lock->value, true);
+	ck_pr_fence_lock();
+	return !value;
+}
+
+CK_CC_INLINE static bool
+ck_spinlock_cas_locked(struct ck_spinlock_cas *lock)
+{
+	bool r = ck_pr_load_uint(&lock->value);
+
+	ck_pr_fence_acquire();
+	return r;
+}
+
+CK_CC_INLINE static void
+ck_spinlock_cas_lock(struct ck_spinlock_cas *lock)
+{
+
+	while (ck_pr_cas_uint(&lock->value, false, true) == false) {
+		while (ck_pr_load_uint(&lock->value) == true)
+			ck_pr_stall();
+	}
+
+	ck_pr_fence_lock();
+	return;
+}
+
+CK_CC_INLINE static void
+ck_spinlock_cas_lock_eb(struct ck_spinlock_cas *lock)
+{
+	ck_backoff_t backoff = CK_BACKOFF_INITIALIZER;
+
+	while (ck_pr_cas_uint(&lock->value, false, true) == false)
+		ck_backoff_eb(&backoff);
+
+	ck_pr_fence_lock();
+	return;
+}
+
+CK_CC_INLINE static void
+ck_spinlock_cas_unlock(struct ck_spinlock_cas *lock)
+{
+
+	/* Set lock state to unlocked. */
+	ck_pr_fence_unlock();
+	ck_pr_store_uint(&lock->value, false);
+	return;
+}
+
+CK_ELIDE_PROTOTYPE(ck_spinlock_cas, ck_spinlock_cas_t,
+    ck_spinlock_cas_locked, ck_spinlock_cas_lock,
+    ck_spinlock_cas_locked, ck_spinlock_cas_unlock)
+
+CK_ELIDE_TRYLOCK_PROTOTYPE(ck_spinlock_cas, ck_spinlock_cas_t,
+    ck_spinlock_cas_locked, ck_spinlock_cas_trylock)
+
+#endif /* CK_F_SPINLOCK_CAS */
+#endif /* CK_SPINLOCK_CAS_H */