Fix powerpc uatomic 4-byte cmpxchg (cmpd -> cmpw)

[urcu.git] / urcu-qsbr-static.h

diff --git a/urcu-qsbr-static.h b/urcu-qsbr-static.h
index e49a04186104bbc2b3b769665a1fb6cb59fe7911..86f0fc507449451d70f276571d3c6aa1be61d98a 100644 (file)
--- a/urcu-qsbr-static.h
+++ b/urcu-qsbr-static.h
@@ -43,6 +43,10 @@
 #include <urcu/list.h>
 #include <urcu/urcu-futex.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif 
+
 /*
  * This code section can only be included in LGPL 2.1 compatible source code.
  * See below for the function call wrappers which can be used in code meant to
@@ -53,7 +57,7 @@
 
 /*
  * If a reader is really non-cooperative and refuses to commit its
- * urcu_reader.ctr count to memory (there is no barrier in the reader
+ * rcu_reader.ctr count to memory (there is no barrier in the reader
  * per-se), kick it after a few loops waiting for it.
  */
 #define KICK_READER_LOOPS 10000
@@ -117,11 +121,6 @@ static inline void debug_yield_init(void)
 }
 #endif
 
-static inline void reader_barrier()
-{
-       smp_mb();
-}
-
 #define RCU_GP_ONLINE          (1UL << 0)
 #define RCU_GP_CTR             (1UL << 1)
 
@@ -130,17 +129,17 @@ static inline void reader_barrier()
  * Using a int rather than a char to eliminate false register dependencies
  * causing stalls on some architectures.
  */
-extern unsigned long urcu_gp_ctr;
+extern unsigned long rcu_gp_ctr;
 
-struct urcu_reader {
+struct rcu_reader {
        /* Data used by both reader and synchronize_rcu() */
        unsigned long ctr;
        /* Data used for registry */
-       struct list_head head __attribute__((aligned(CACHE_LINE_SIZE)));
+       struct list_head node __attribute__((aligned(CACHE_LINE_SIZE)));
        pthread_t tid;
 };
 
-extern struct urcu_reader __thread urcu_reader;
+extern struct rcu_reader __thread rcu_reader;
 
 extern int gp_futex;
 
@@ -156,31 +155,17 @@ static inline void wake_up_gp(void)
        }
 }
 
-#if (BITS_PER_LONG < 64)
-static inline int rcu_gp_ongoing(unsigned long *value)
+static inline int rcu_gp_ongoing(unsigned long *ctr)
 {
-       unsigned long reader_gp;
+       unsigned long v;
 
-       if (value == NULL)
-               return 0;
-       reader_gp = LOAD_SHARED(*value);
-       return reader_gp && ((reader_gp ^ urcu_gp_ctr) & RCU_GP_CTR);
+       v = LOAD_SHARED(*ctr);
+       return v && (v != rcu_gp_ctr);
 }
-#else /* !(BITS_PER_LONG < 64) */
-static inline int rcu_gp_ongoing(unsigned long *value)
-{
-       unsigned long reader_gp;
-
-       if (value == NULL)
-               return 0;
-       reader_gp = LOAD_SHARED(*value);
-       return reader_gp && (reader_gp - urcu_gp_ctr > ULONG_MAX / 2);
-}
-#endif  /* !(BITS_PER_LONG < 64) */
 
 static inline void _rcu_read_lock(void)
 {
-       rcu_assert(urcu_reader.ctr);
+       rcu_assert(rcu_reader.ctr);
 }
 
 static inline void _rcu_read_unlock(void)
@@ -190,8 +175,8 @@ static inline void _rcu_read_unlock(void)
 static inline void _rcu_quiescent_state(void)
 {
        smp_mb();       
-       _STORE_SHARED(urcu_reader.ctr, _LOAD_SHARED(urcu_gp_ctr));
-       smp_mb();       /* write urcu_reader.ctr before read futex */
+       _STORE_SHARED(rcu_reader.ctr, _LOAD_SHARED(rcu_gp_ctr));
+       smp_mb();       /* write rcu_reader.ctr before read futex */
        wake_up_gp();
        smp_mb();
 }
@@ -199,15 +184,19 @@ static inline void _rcu_quiescent_state(void)
 static inline void _rcu_thread_offline(void)
 {
        smp_mb();
-       STORE_SHARED(urcu_reader.ctr, 0);
-       smp_mb();       /* write urcu_reader.ctr before read futex */
+       STORE_SHARED(rcu_reader.ctr, 0);
+       smp_mb();       /* write rcu_reader.ctr before read futex */
        wake_up_gp();
 }
 
 static inline void _rcu_thread_online(void)
 {
-       _STORE_SHARED(urcu_reader.ctr, LOAD_SHARED(urcu_gp_ctr));
+       _STORE_SHARED(rcu_reader.ctr, LOAD_SHARED(rcu_gp_ctr));
        smp_mb();
 }
 
+#ifdef __cplusplus 
+}
+#endif
+
 #endif /* _URCU_QSBR_STATIC_H */