1 files changed, 135 insertions, 0 deletions
diff --git a/erts/include/internal/pthread/ethr_event.h b/erts/include/internal/pthread/ethr_event.h
new file mode 100644
index 0000000000..4c29b28536
--- /dev/null
+++ b/erts/include/internal/pthread/ethr_event.h
@@ -0,0 +1,135 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2009-2011. All Rights Reserved.
+ *
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ *
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+/*
+ * Author: Rickard Green
+ */
+
+#if defined(ETHR_HAVE_LINUX_FUTEX) && defined(ETHR_HAVE_NATIVE_ATOMICS)
+/* --- Linux futex implementation of ethread events ------------------------- */
+#define ETHR_LINUX_FUTEX_IMPL__
+
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <linux/futex.h>
+#include <sys/time.h>
+
+#define ETHR_EVENT_OFF_WAITER__		((ethr_sint32_t) -1)
+#define ETHR_EVENT_OFF__		((ethr_sint32_t) 1)
+#define ETHR_EVENT_ON__ 		((ethr_sint32_t) 0)
+
+#if defined(FUTEX_WAIT_PRIVATE) && defined(FUTEX_WAKE_PRIVATE)
+#  define ETHR_FUTEX_WAIT__ FUTEX_WAIT_PRIVATE
+#  define ETHR_FUTEX_WAKE__ FUTEX_WAKE_PRIVATE
+#else
+#  define ETHR_FUTEX_WAIT__ FUTEX_WAIT
+#  define ETHR_FUTEX_WAKE__ FUTEX_WAKE
+#endif
+
+typedef struct {
+    ethr_atomic32_t futex;
+} ethr_event;
+
+#define ETHR_FUTEX__(FTX, OP, VAL)			\
+  (-1 == syscall(__NR_futex,				\
+		 (void *) ethr_atomic32_addr((FTX)),	\
+		 (OP),					\
+		 (int) (VAL),				\
+		 NULL,					\
+		 NULL,					\
+		 0)					\
+   ? errno : 0)
+
+#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_EVENT_IMPL__)
+
+static void ETHR_INLINE
+ETHR_INLINE_FUNC_NAME_(ethr_event_set)(ethr_event *e)
+{
+    ethr_sint32_t val;
+    ETHR_MEMORY_BARRIER;
+    val = ethr_atomic32_xchg(&e->futex, ETHR_EVENT_ON__);
+    if (val == ETHR_EVENT_OFF_WAITER__) {
+	int res = ETHR_FUTEX__(&e->futex, ETHR_FUTEX_WAKE__, 1);
+	if (res != 0)
+	    ETHR_FATAL_ERROR__(res);
+    }
+}
+
+static void ETHR_INLINE
+ETHR_INLINE_FUNC_NAME_(ethr_event_reset)(ethr_event *e)
+{
+    ethr_atomic32_set(&e->futex, ETHR_EVENT_OFF__);
+    ETHR_MEMORY_BARRIER;
+}
+
+#endif
+
+#elif defined(ETHR_PTHREADS)
+/* --- Posix mutex/cond implementation of events ---------------------------- */
+
+typedef struct {
+    ethr_atomic32_t state;
+    pthread_mutex_t mtx;
+    pthread_cond_t cnd;
+} ethr_event;
+
+#define ETHR_EVENT_OFF_WAITER__		-1L
+#define ETHR_EVENT_OFF__		1L
+#define ETHR_EVENT_ON__ 		0L
+
+#if defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_EVENT_IMPL__)
+
+static void ETHR_INLINE
+ETHR_INLINE_FUNC_NAME_(ethr_event_set)(ethr_event *e)
+{
+    ethr_sint32_t val;
+    ETHR_MEMORY_BARRIER;
+    val = ethr_atomic32_xchg(&e->state, ETHR_EVENT_ON__);
+    if (val == ETHR_EVENT_OFF_WAITER__) {
+	int res = pthread_mutex_lock(&e->mtx);
+	if (res != 0)
+	    ETHR_FATAL_ERROR__(res);
+	res = pthread_cond_signal(&e->cnd);
+	if (res != 0)
+	    ETHR_FATAL_ERROR__(res);
+	res = pthread_mutex_unlock(&e->mtx);
+	if (res != 0)
+	    ETHR_FATAL_ERROR__(res);
+    }
+}
+
+static void ETHR_INLINE
+ETHR_INLINE_FUNC_NAME_(ethr_event_reset)(ethr_event *e)
+{
+    ethr_atomic32_set(&e->state, ETHR_EVENT_OFF__);
+    ETHR_MEMORY_BARRIER;
+}
+
+#endif
+
+#endif
+
+int ethr_event_init(ethr_event *e);
+int ethr_event_destroy(ethr_event *e);
+int ethr_event_wait(ethr_event *e);
+int ethr_event_swait(ethr_event *e, int spincount);
+#if !defined(ETHR_TRY_INLINE_FUNCS) || defined(ETHR_EVENT_IMPL__)
+void ethr_event_set(ethr_event *e);
+void ethr_event_reset(ethr_event *e);
+#endif