Cleanup: Re-organise source dir

[userspace-rcu.git] / include / urcu / system.h

diff --git a/include/urcu/system.h b/include/urcu/system.h
new file mode 100644 (file)
index 0000000..faae390
--- /dev/null
+++ b/include/urcu/system.h
@@ -0,0 +1,59 @@
+#ifndef _URCU_SYSTEM_H
+#define _URCU_SYSTEM_H
+
+/*
+ * system.h
+ *
+ * System definitions.
+ *
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ */
+
+#include <urcu/compiler.h>
+#include <urcu/arch.h>
+
+/*
+ * Identify a shared load. A cmm_smp_rmc() or cmm_smp_mc() should come
+ * before the load.
+ */
+#define _CMM_LOAD_SHARED(p)           CMM_ACCESS_ONCE(p)
+
+/*
+ * Load a data from shared memory, doing a cache flush if required.
+ */
+#define CMM_LOAD_SHARED(p)                     \
+       __extension__                   \
+       ({                              \
+               cmm_smp_rmc();          \
+               _CMM_LOAD_SHARED(p);    \
+       })
+
+/*
+ * Identify a shared store. A cmm_smp_wmc() or cmm_smp_mc() should
+ * follow the store.
+ */
+#define _CMM_STORE_SHARED(x, v)        __extension__ ({ CMM_ACCESS_ONCE(x) = (v); })
+
+/*
+ * Store v into x, where x is located in shared memory. Performs the
+ * required cache flush after writing. Returns v.
+ */
+#define CMM_STORE_SHARED(x, v)                                         \
+       __extension__                                                   \
+       ({                                                              \
+               __typeof__(x) _v = _CMM_STORE_SHARED(x, v);             \
+               cmm_smp_wmc();                                          \
+               _v = _v;        /* Work around clang "unused result" */ \
+       })
+
+#endif /* _URCU_SYSTEM_H */