tests/regression/rcutorture: Use urcu-wait

pthread_cond_wait(3) can have spurious wakeups on some OS. To detect
such spurious wakeup, a global variable is shared between the waiter and
the waker.

We can use urcu-wait instead.

Change-Id: I6a2d2f3c9104ea23df16a7c8ba3557bb5d58306c
Signed-off-by: Olivier Dion <odion@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/tests/regression/rcutorture.h b/tests/regression/rcutorture.h
index e20d82eeb15df7873f74e8b795b16f8d111110ec..93fdf0cf373c6623dafec968b64257bb96a24bd6 100644 (file)
--- a/tests/regression/rcutorture.h
+++ b/tests/regression/rcutorture.h
@@ -56,6 +56,8 @@
 #include <stdlib.h>
 #include "tap.h"
 
+#include "urcu-wait.h"
+
 #define NR_TESTS       1
 
 DEFINE_PER_THREAD(long long, n_reads_pt);
@@ -334,37 +336,15 @@ void *rcu_read_stress_test(void *arg __attribute__((unused)))
        return (NULL);
 }
 
-static pthread_mutex_t call_rcu_test_mutex = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t call_rcu_test_cond = PTHREAD_COND_INITIALIZER;
-static bool call_rcu_wait;
+static DEFINE_URCU_WAIT_QUEUE(call_rcu_waiters);
 
 static
 void rcu_update_stress_test_rcu(struct rcu_head *head __attribute__((unused)))
 {
-       int ret;
+       struct urcu_waiters waiters;
 
-       ret = pthread_mutex_lock(&call_rcu_test_mutex);
-       if (ret) {
-               errno = ret;
-               diag("pthread_mutex_lock: %s",
-                       strerror(errno));
-               abort();
-       }
-       ret = pthread_cond_signal(&call_rcu_test_cond);
-       if (ret) {
-               errno = ret;
-               diag("pthread_cond_signal: %s",
-                       strerror(errno));
-               abort();
-       }
-       call_rcu_wait = false;
-       ret = pthread_mutex_unlock(&call_rcu_test_mutex);
-       if (ret) {
-               errno = ret;
-               diag("pthread_mutex_unlock: %s",
-                       strerror(errno));
-               abort();
-       }
+       urcu_move_waiters(&waiters, &call_rcu_waiters);
+       urcu_wake_all_waiters(&waiters);
 }
 
 static
@@ -419,52 +399,13 @@ void *rcu_update_stress_test(void *arg __attribute__((unused)))
                        break;
                case WRITER_STATE_CALL_RCU:
                {
-                       int ret;
-
-                       ret = pthread_mutex_lock(&call_rcu_test_mutex);
-                       if (ret) {
-                               errno = ret;
-                               diag("pthread_mutex_lock: %s",
-                                       strerror(errno));
-                               abort();
-                       }
+                       DEFINE_URCU_WAIT_NODE(wait, URCU_WAIT_WAITING);
+
+                       urcu_wait_add(&call_rcu_waiters, &wait);
+
                        call_rcu(&rh, rcu_update_stress_test_rcu);
 
-                       /*
-                        * Our MacOS X test machine with the following
-                        * config:
-                        * 15.6.0 Darwin Kernel Version 15.6.0
-                        * root:xnu-3248.60.10~1/RELEASE_X86_64
-                        * appears to have issues with liburcu-signal
-                        * signal being delivered on top of
-                        * pthread_cond_wait. It seems to make the
-                        * thread continue, and therefore corrupt the
-                        * rcu_head. Work around this issue by
-                        * unregistering the RCU read-side thread
-                        * immediately after call_rcu (call_rcu needs
-                        * us to be registered RCU readers).
-                        */
-                       call_rcu_wait = true;
-                       /* Offline for pthread_cond_wait. */
-                       put_thread_offline();
-                       do {
-                               ret = pthread_cond_wait(&call_rcu_test_cond,
-                                                       &call_rcu_test_mutex);
-                       } while (call_rcu_wait);
-                       put_thread_online();
-                       if (ret) {
-                               errno = ret;
-                               diag("pthread_cond_signal: %s",
-                                       strerror(errno));
-                               abort();
-                       }
-                       ret = pthread_mutex_unlock(&call_rcu_test_mutex);
-                       if (ret) {
-                               errno = ret;
-                               diag("pthread_mutex_unlock: %s",
-                                       strerror(errno));
-                               abort();
-                       }
+                       urcu_adaptative_busy_wait(&wait);
                        break;
                }
                case WRITER_STATE_POLL_RCU: