Add CMM memory model

[urcu.git] / include / urcu / static / pointer.h

diff --git a/include/urcu/static/pointer.h b/include/urcu/static/pointer.h
index 055a9b884524581a58610a7f9f40dbe0df780a76..9dc0d3eaa5f4c6177fc503449153cd08f78267ec 100644 (file)
--- a/include/urcu/static/pointer.h
+++ b/include/urcu/static/pointer.h
@@ -82,23 +82,8 @@ extern "C" {
  * -Wincompatible-pointer-types errors.  Using the statement expression
  * makes it an rvalue and gets rid of the const-ness.
  */
-#ifdef __URCU_DEREFERENCE_USE_ATOMIC_CONSUME
-# define _rcu_dereference(p) __extension__ ({                                          \
-                               __typeof__(__extension__ ({                             \
-                                       __typeof__(p) __attribute__((unused)) _________p0 = { 0 }; \
-                                       _________p0;                                    \
-                               })) _________p1;                                        \
-                               __atomic_load(&(p), &_________p1, __ATOMIC_CONSUME);    \
-                               (_________p1);                                          \
-                       })
-#else
-# define _rcu_dereference(p) __extension__ ({                                          \
-                               __typeof__(p) _________p1 = CMM_LOAD_SHARED(p);         \
-                               cmm_smp_read_barrier_depends();                         \
-                               (_________p1);                                          \
-                       })
-#endif
-
+# define _rcu_dereference(p)                   \
+       uatomic_load(&(p), CMM_CONSUME)
 /**
  * _rcu_cmpxchg_pointer - same as rcu_assign_pointer, but tests if the pointer
  * is as expected by "old". If succeeds, returns the previous pointer to the
@@ -106,7 +91,7 @@ extern "C" {
  * using synchronize_rcu(). If fails (unexpected value), returns old (which
  * should not be freed !).
  *
- * uatomic_cmpxchg() acts as both release and acquire barriers.
+ * uatomic_cmpxchg() acts as both release and acquire barriers on success.
  *
  * This macro is less than 10 lines long.  The intent is that this macro
  * meets the 10-line criterion in LGPL, allowing this function to be
@@ -117,8 +102,9 @@ extern "C" {
        ({                                                              \
                __typeof__(*p) _________pold = (old);                   \
                __typeof__(*p) _________pnew = (_new);                  \
-               uatomic_cmpxchg(p, _________pold, _________pnew);       \
-       })
+               uatomic_cmpxchg_mo(p, _________pold, _________pnew,     \
+                                  CMM_SEQ_CST, CMM_RELAXED);           \
+       });
 
 /**
  * _rcu_xchg_pointer - same as rcu_assign_pointer, but returns the previous
@@ -135,17 +121,17 @@ extern "C" {
        __extension__                                   \
        ({                                              \
                __typeof__(*p) _________pv = (v);       \
-               uatomic_xchg(p, _________pv);           \
+               uatomic_xchg_mo(p, _________pv,         \
+                               CMM_SEQ_CST);           \
        })
 
 
-#define _rcu_set_pointer(p, v)                         \
-       do {                                            \
-               __typeof__(*p) _________pv = (v);       \
-               if (!__builtin_constant_p(v) ||         \
-                   ((v) != NULL))                      \
-                       cmm_wmb();                              \
-               uatomic_set(p, _________pv);            \
+#define _rcu_set_pointer(p, v)                                         \
+       do {                                                            \
+               __typeof__(*p) _________pv = (v);                       \
+               uatomic_store(p, _________pv,                           \
+                       __builtin_constant_p(v) && (v) == NULL ?        \
+                       CMM_RELAXED : CMM_RELEASE);                     \
        } while (0)
 
 /**