1 files changed, 122 insertions, 0 deletions
diff --git a/lib/libthr/thread/thr_setschedparam.c b/lib/libthr/thread/thr_setschedparam.c
new file mode 100644
index 0000000..e90def4
--- /dev/null
+++ b/lib/libthr/thread/thr_setschedparam.c
@@ -0,0 +1,122 @@
+/*
+ * Copyright (c) 1998 Daniel Eischen <eischen@vigrid.com>.
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by Daniel Eischen.
+ * 4. 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 DANIEL EISCHEN 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 <errno.h>
+#include <sys/param.h>
+#include <pthread.h>
+#include <stdlib.h>
+#include "thr_private.h"
+
+__weak_reference(_pthread_getschedparam, pthread_getschedparam);
+__weak_reference(_pthread_setschedparam, pthread_setschedparam);
+
+int
+_pthread_getschedparam(pthread_t pthread, int *policy, 
+    struct sched_param *param)
+{
+	if (param == NULL || policy == NULL)
+		return (EINVAL);
+	if (_find_thread(pthread) == ESRCH)
+		return (ESRCH);
+	param->sched_priority = pthread->base_priority;
+	*policy = pthread->attr.sched_policy;
+	return(0);
+}
+
+int
+_pthread_setschedparam(pthread_t pthread, int policy, 
+	const struct sched_param *param)
+{
+	struct pthread_mutex *mtx;
+	int old_prio;
+
+	mtx = NULL;
+	old_prio = 0;
+	if ((param == NULL) || (policy < SCHED_FIFO) || (policy > SCHED_RR))
+		return (EINVAL);
+	if ((param->sched_priority < PTHREAD_MIN_PRIORITY) ||
+	    (param->sched_priority > PTHREAD_MAX_PRIORITY))
+		return (ENOTSUP);
+	if (_find_thread(pthread) != 0)
+		return (ESRCH);
+
+	/*
+	 * If the pthread is waiting on a mutex grab it now. Doing it now
+	 * even though we do not need it immediately greatly simplifies the
+	 * LOR avoidance code.
+	 */
+	do {
+		_thread_critical_enter(pthread);
+		if (pthread->state == PS_MUTEX_WAIT) {
+			mtx = pthread->data.mutex;
+			if (_spintrylock(&mtx->lock) == EBUSY)
+				_thread_critical_exit(pthread);
+			else
+				break;
+		} else {
+			break;
+		}
+	} while (1);
+
+	PTHREAD_ASSERT(pthread->active_priority >= pthread->inherited_priority,
+	    "active priority cannot be less than inherited priority");
+	old_prio = pthread->base_priority;
+	pthread->base_priority = param->sched_priority;
+	if (param->sched_priority <= pthread->active_priority) {
+		/*
+		 * Active priority is affected only if it was the
+		 * base priority and the new base priority is lower.
+		 */
+		if (pthread->active_priority == old_prio &&
+		    pthread->active_priority != pthread->inherited_priority) {
+			pthread->active_priority = param->sched_priority;
+			readjust_priorities(pthread, mtx);
+		}
+
+	} else {
+		/*
+		 * New base priority is greater than active priority. This
+		 * only affects threads that are holding priority inheritance
+		 * mutexes this thread is waiting on and its position in the
+		 * queue.
+		 */
+		pthread->active_priority = param->sched_priority;
+		readjust_priorities(pthread, mtx);
+
+	}
+	pthread->attr.sched_policy = policy;
+	_thread_critical_exit(pthread);
+	if (mtx != NULL)
+		_SPINUNLOCK(&mtx->lock);
+	return(0);
+}