/*
- * urcu.c
+ * urcu-qsbr.c
*
- * Userspace RCU library
+ * Userspace RCU QSBR library
*
* Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
* Copyright (c) 2009 Paul E. McKenney, IBM Corporation.
#include <errno.h>
#include <poll.h>
-#include "urcu-qsbr.h"
+#include "urcu-qsbr-static.h"
/* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
-//#include "urcu.h"
+#include "urcu-qsbr.h"
pthread_mutex_t urcu_mutex = PTHREAD_MUTEX_INITIALIZER;
struct reader_registry {
pthread_t tid;
long *rcu_reader_qs_gp;
- char *need_mb;
};
#ifdef DEBUG_YIELD
#endif
static struct reader_registry *registry;
-static char __thread need_mb;
static int num_readers, alloc_readers;
-void internal_urcu_lock(void)
+static void internal_urcu_lock(void)
{
int ret;
perror("Error in pthread mutex lock");
exit(-1);
}
- if (need_mb) {
- smp_mb();
- need_mb = 0;
- smp_mb();
- }
poll(NULL,0,10);
}
#endif /* #else #ifndef DISTRUST_SIGNALS_EXTREME */
}
-void internal_urcu_unlock(void)
+static void internal_urcu_unlock(void)
{
int ret;
smp_mb();
}
-void wait_for_quiescent_state(void)
+static void wait_for_quiescent_state(void)
{
struct reader_registry *index;
+ if (rcu_reader_qs_gp & 1)
+ rcu_reader_qs_gp = urcu_gp_ctr + 1;
+
if (!registry)
return;
/*
void synchronize_rcu(void)
{
+ int was_online;
+
+ was_online = rcu_reader_qs_gp & 1;
+
+ /*
+ * Mark the writer thread offline to make sure we don't wait for
+ * our own quiescent state. This allows using synchronize_rcu() in
+ * threads registered as readers.
+ */
+ if (was_online)
+ _rcu_thread_offline();
+
internal_urcu_lock();
force_mb_all_threads();
urcu_gp_ctr += 2;
wait_for_quiescent_state();
force_mb_all_threads();
internal_urcu_unlock();
+
+ if (was_online)
+ _rcu_thread_online();
}
/*
return oldptr;
}
+void rcu_quiescent_state(void)
+{
+ _rcu_quiescent_state();
+}
+
+void rcu_thread_offline(void)
+{
+ _rcu_thread_offline();
+}
+
+void rcu_thread_online(void)
+{
+ _rcu_thread_online();
+}
+
static void rcu_add_reader(pthread_t id)
{
struct reader_registry *oldarray;
registry[num_readers].tid = id;
/* reference to the TLS of _this_ reader thread. */
registry[num_readers].rcu_reader_qs_gp = &rcu_reader_qs_gp;
- registry[num_readers].need_mb = &need_mb;
num_readers++;
}