Fix: handle sys_futex() FUTEX_WAIT interrupted by signal

[urcu.git] / urcu / system.h

diff --git a/urcu/system.h b/urcu/system.h
index 86ee6b197997017577bdf413af01b5bb2f9e7ddb..faae39055484875b237dd62dd0928e9903725da1 100644 (file)
--- a/urcu/system.h
+++ b/urcu/system.h
@@ -8,47 +8,52 @@
  *
  * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
- * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
- * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
+ * 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:
  *
- * Permission is hereby granted to use or copy this program
- * for any purpose,  provided the above notices are retained on all copies.
- * Permission to modify the code and to distribute modified code is granted,
- * provided the above notices are retained, and a notice that the code was
- * modified is included with the above copyright notice.
+ * 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.
+ * Identify a shared load. A cmm_smp_rmc() or cmm_smp_mc() should come
+ * before the load.
  */
-#define _CMM_LOAD_SHARED(p)           CAA_ACCESS_ONCE(p)
+#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.
+ * Identify a shared store. A cmm_smp_wmc() or cmm_smp_mc() should
+ * follow the store.
  */
-#define _CMM_STORE_SHARED(x, v)        ({ CAA_ACCESS_ONCE(x) = (v); })
+#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.
+ * 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)         \
-       ({                              \
-               typeof(x) _v = _CMM_STORE_SHARED(x, v); \
-               cmm_smp_wmc();          \
-               _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 */