Remove parameter from rcu_read_lock()

[urcu.git] / urcu.c

diff --git a/urcu.c b/urcu.c
index 4362217d49ab4020c0bd199c30410733f32bbd89..31cdf6fc08b61c14e0a8f47d93154c0d54599ccc 100644 (file)
--- a/urcu.c
+++ b/urcu.c
@@ -19,10 +19,10 @@
 
 pthread_mutex_t urcu_mutex = PTHREAD_MUTEX_INITIALIZER;
 
-/* Global quiescent period parity */
-int urcu_qparity;
+/* Global grace period counter */
+int urcu_gp_ctr;
 
-int __thread urcu_active_readers[2];
+int __thread urcu_active_readers;
 
 /* Thread IDs of registered readers */
 #define INIT_NUM_THREADS 4
@@ -33,7 +33,8 @@ struct reader_data {
 };
 
 #ifdef DEBUG_YIELD
-int yield_active;
+unsigned int yield_active;
+unsigned int __thread rand_yield;
 #endif
 
 static struct reader_data *reader_data;
@@ -64,11 +65,9 @@ void internal_urcu_unlock(void)
 /*
  * called with urcu_mutex held.
  */
-static int switch_next_urcu_qparity(void)
+static void switch_next_urcu_qparity(void)
 {
-       int old_parity = urcu_qparity;
-       urcu_qparity = 1 - old_parity;
-       return old_parity;
+       urcu_gp_ctr ^= RCU_GP_CTR_BIT;
 }
 
 static void force_mb_all_threads(void)
@@ -100,7 +99,7 @@ static void force_mb_all_threads(void)
        debug_yield_write();
 }
 
-void wait_for_quiescent_state(int parity)
+void wait_for_quiescent_state(void)
 {
        struct reader_data *index;
 
@@ -112,7 +111,7 @@ void wait_for_quiescent_state(int parity)
                /*
                 * BUSY-LOOP.
                 */
-               while (index->urcu_active_readers[parity] != 0)
+               while (rcu_old_gp_ongoing(index->urcu_active_readers))
                        barrier();
        }
        /*
@@ -126,19 +125,17 @@ void wait_for_quiescent_state(int parity)
 
 static void switch_qparity(void)
 {
-       int prev_parity;
-
        /* All threads should read qparity before accessing data structure. */
        /* Write ptr before changing the qparity */
        force_mb_all_threads();
        debug_yield_write();
-       prev_parity = switch_next_urcu_qparity();
+       switch_next_urcu_qparity();
        debug_yield_write();
 
        /*
         * Wait for previous parity to be empty of readers.
         */
-       wait_for_quiescent_state(prev_parity);
+       wait_for_quiescent_state();
 }
 
 void synchronize_rcu(void)
@@ -211,7 +208,7 @@ void urcu_add_reader(pthread_t id)
        }
        reader_data[num_readers].tid = id;
        /* reference to the TLS of _this_ reader thread. */
-       reader_data[num_readers].urcu_active_readers = urcu_active_readers;
+       reader_data[num_readers].urcu_active_readers = &urcu_active_readers;
        num_readers++;
 }