Fix: urcu-bp: only teardown call-rcu worker in destructor

Do not invoke urcu_call_rcu_exit() every time a reader thread
unregisters from urcu-bp. This causes pthread join hangs observed on
Cygwin.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Change-Id: I4e5c6e06df9966d65f2dcf01bb3281cbfcb05a5b

diff --git a/src/urcu-bp.c b/src/urcu-bp.c
index 35ac9dbed12b01e19166e93e5f176a9c2dc490da..1f9a03818228e0c72941de77baf7f3bf720cd0d9 100644 (file)
--- a/src/urcu-bp.c
+++ b/src/urcu-bp.c
@@ -120,7 +120,9 @@ enum membarrier_cmd {
 static
 void __attribute__((constructor)) _urcu_bp_init(void);
 static
-void __attribute__((destructor)) urcu_bp_exit(void);
+void urcu_bp_exit(void);
+static
+void __attribute__((destructor)) urcu_bp_exit_destructor(void);
 static void urcu_call_rcu_exit(void);
 
 #ifndef CONFIG_RCU_FORCE_SYS_MEMBARRIER
@@ -663,8 +665,6 @@ void _urcu_bp_init(void)
 static
 void urcu_bp_exit(void)
 {
-       urcu_call_rcu_exit();
-
        mutex_lock(&init_lock);
        if (!--urcu_bp_refcount) {
                struct registry_chunk *chunk, *tmp;
@@ -683,6 +683,13 @@ void urcu_bp_exit(void)
        mutex_unlock(&init_lock);
 }
 
+static
+void urcu_bp_exit_destructor(void)
+{
+       urcu_call_rcu_exit();
+       urcu_bp_exit();
+}
+
 /*
  * Holding the rcu_gp_lock and rcu_registry_lock across fork will make
  * sure we fork() don't race with a concurrent thread executing with