1 files changed, 72 insertions, 0 deletions
diff --git a/lib/libkse/thread/thr_yield.c b/lib/libkse/thread/thr_yield.c
new file mode 100644
index 0000000..7094609
--- /dev/null
+++ b/lib/libkse/thread/thr_yield.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the author nor the names of any co-contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+#include <pthread.h>
+#include "thr_private.h"
+
+int _sched_yield(void);
+
+__weak_reference(_sched_yield, sched_yield);
+__weak_reference(_pthread_yield, pthread_yield);
+
+int
+_sched_yield(void)
+{
+	struct pthread	*curthread = _get_curthread();
+
+	if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM)
+		return (__sys_sched_yield());
+
+	/* Reset the accumulated time slice value for the current thread: */
+	curthread->slice_usec = -1;
+
+	/* Schedule the next thread: */
+	_thr_sched_switch(curthread);
+	/* Always return no error. */
+	return(0);
+}
+
+/* Draft 4 yield */
+void
+_pthread_yield(void)
+{
+	struct pthread	*curthread = _get_curthread();
+
+	if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) {
+		__sys_sched_yield();
+		return;
+	}
+
+	/* Reset the accumulated time slice value for the current thread: */
+	curthread->slice_usec = -1;
+
+	/* Schedule the next thread: */
+	_thr_sched_switch(curthread);
+}