urcu/compiler: Add urcu_static_assert

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

diff --git a/include/urcu/uatomic.h b/include/urcu/uatomic.h
index b7b1d89d0ca1c6e66209ccfcfc4f2b76f9ebaf36..aca9a63da3af2d5301b92daa47fa5cdbfcedfa4b 100644 (file)
--- a/include/urcu/uatomic.h
+++ b/include/urcu/uatomic.h
@@ -6,8 +6,66 @@
 #define _URCU_UATOMIC_H
 
 #include <urcu/arch.h>
+#include <urcu/compiler.h>
+#include <urcu/config.h>
 
-#if defined(URCU_ARCH_X86)
+enum cmm_memorder {
+       CMM_RELAXED = 0,
+       CMM_CONSUME = 1,
+       CMM_ACQUIRE = 2,
+       CMM_RELEASE = 3,
+       CMM_ACQ_REL = 4,
+       CMM_SEQ_CST = 5,
+       CMM_SEQ_CST_FENCE = 6,
+};
+
+#ifdef CONFIG_RCU_USE_ATOMIC_BUILTINS
+
+/*
+ * Make sure that CMM_SEQ_CST_FENCE is not equivalent to other memory orders.
+ */
+urcu_static_assert(CMM_RELAXED == __ATOMIC_RELAXED, "", cmm_relaxed);
+urcu_static_assert(CMM_CONSUME == __ATOMIC_CONSUME, "", cmm_consume);
+urcu_static_assert(CMM_ACQUIRE == __ATOMIC_ACQUIRE, "", cmm_acquire);
+urcu_static_assert(CMM_RELEASE == __ATOMIC_RELEASE, "", cmm_release);
+urcu_static_assert(CMM_ACQ_REL == __ATOMIC_ACQ_REL, "", cmm_acq_rel);
+urcu_static_assert(CMM_SEQ_CST == __ATOMIC_SEQ_CST, "", cmm_seq_cst);
+
+/*
+ * This is not part of the public API. It it used internally to implement the
+ * CMM_SEQ_CST_FENCE memory order.
+ *
+ * NOTE: Using switch here instead of if statement to avoid -Wduplicated-cond
+ * warning when memory order is conditionally determined.
+ */
+static inline void cmm_seq_cst_fence_after_atomic(enum cmm_memorder mo)
+{
+       switch (mo) {
+       case CMM_SEQ_CST_FENCE:
+               cmm_smp_mb();
+               break;
+       default:
+               break;
+       }
+}
+
+#endif
+
+/*
+ * This is not part of the public API. It is used internally to convert from the
+ * CMM memory model to the C11 memory model.
+ */
+static inline int cmm_to_c11(int mo)
+{
+       if (mo == CMM_SEQ_CST_FENCE) {
+               return CMM_SEQ_CST;
+       }
+       return mo;
+}
+
+#if defined(CONFIG_RCU_USE_ATOMIC_BUILTINS)
+#include <urcu/uatomic/builtins.h>
+#elif defined(URCU_ARCH_X86)
 #include <urcu/uatomic/x86.h>
 #elif defined(URCU_ARCH_PPC)
 #include <urcu/uatomic/ppc.h>