From 68a614328aa9b53faf63f241a7ed6167ddd4dfbd Mon Sep 17 00:00:00 2001
From: Samy Al Bahra <sbahra@repnop.org>
Date: Fri, 12 Jul 2013 23:44:30 -0400
Subject: [PATCH] ck_elide: General lock elision framework.

This allows users to wrap any single-argument lock implementation
to support lock elision. Built-in lock types will make use of this
facility.
---
 include/ck_elide.h | 104 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 include/ck_elide.h

diff --git a/include/ck_elide.h b/include/ck_elide.h
new file mode 100644
index 0000000..79d60b5
--- /dev/null
+++ b/include/ck_elide.h
@@ -0,0 +1,104 @@
+/*
+ * Copyright 2013 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_ELIDE_H
+#define _CK_ELIDE_H
+
+#include <ck_cc.h>
+#include <ck_pr.h>
+
+#ifdef CK_F_PR_RTM
+#define CK_ELIDE_PROTOTYPE(N, T, L_P, L, U_P, U)			\
+	CK_CC_INLINE static void					\
+	ck_elide_##N##_lock(T *lock)					\
+	{								\
+									\
+		if (ck_pr_rtm_begin() != CK_PR_RTM_STARTED) {		\
+			L(lock);					\
+			return;						\
+		}							\
+									\
+		if (L_P(lock) == true)					\
+			ck_pr_rtm_abort(0xFF);				\
+									\
+		return;							\
+	}								\
+	CK_CC_INLINE static void					\
+	ck_elide_##N##_unlock(T *lock)					\
+	{								\
+									\
+		if (U_P(lock) == false) {				\
+			ck_pr_rtm_end();				\
+		} else {						\
+			U(lock);					\
+		}							\
+									\
+		return;							\
+	}
+#define CK_ELIDE_TRYLOCK_PROTOTYPE(N, T, TL_P, TL)			\
+	CK_CC_INLINE static bool					\
+	ck_elide_##N##_trylock(T *lock)					\
+	{								\
+									\
+		if (ck_pr_rtm_begin() != CK_PR_RTM_STARTED)		\
+			return false;					\
+									\
+		if (TL_P(lock) == true)					\
+			ck_pr_rtm_abort(0xFF);				\
+									\
+		return true;						\
+	}
+#else
+#define CK_ELIDE_PROTOTYPE(N, T, L_P, U_P, L, U)			\
+	CK_CC_INLINE static void					\
+	ck_elide_##N##_lock(T *lock)					\
+	{								\
+									\
+		L(lock);						\
+		return;							\
+	}								\
+	CK_CC_INLINE static void					\
+	ck_elide_##N##_unlock(T *lock)					\
+	{								\
+									\
+		U(lock);						\
+		return;							\
+	}
+#define CK_ELIDE_TRYLOCK_PROTOTYPE(N, T, TL_P, TL)			\
+	CK_CC_INLINE static bool					\
+	ck_elide_##N##_trylock(T *lock)					\
+	{								\
+									\
+		return TL_P(lock);					\
+	}
+#endif /* CK_F_PR_RTM */
+
+#define CK_ELIDE_LOCK(NAME, LOCK)	ck_elide_##NAME##_lock(LOCK)	
+#define CK_ELIDE_UNLOCK(NAME, LOCK)	ck_elide_##NAME##_unlock(LOCK)
+#define CK_ELIDE_TRYLOCK(NAME, LOCK)	ck_elide_##NAME##_trylock(LOCK)
+
+#endif /* _CK_ELIDE_H */
+