add missing comment to wfstack.c

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

diff --git a/urcu-qsbr-static.h b/urcu-qsbr-static.h
index 2816621f7296d0203e0551d5010d48d9028cfd56..041361799b89694b8f9e8c9f7af0d142d040a44e 100644 (file)
--- a/urcu-qsbr-static.h
+++ b/urcu-qsbr-static.h
@@ -9,7 +9,7 @@
  * TO BE INCLUDED ONLY IN LGPL-COMPATIBLE CODE. See urcu-qsbr.h for linking
  * dynamically with the userspace rcu QSBR library.
  *
- * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  * Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
  *
  * This library is free software; you can redistribute it and/or
@@ -121,11 +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)
 
@@ -140,7 +135,7 @@ 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;
 };
 
@@ -160,27 +155,13 @@ static inline void wake_up_gp(void)
        }
 }
 
-#if (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 ^ rcu_gp_ctr) & RCU_GP_CTR);
-}
-#else /* !(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 - rcu_gp_ctr > ULONG_MAX / 2);
+       v = LOAD_SHARED(*ctr);
+       return v && (v != rcu_gp_ctr);
 }
-#endif  /* !(BITS_PER_LONG < 64) */
 
 static inline void _rcu_read_lock(void)
 {