/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1994-2007, Dave Pare, Jeff Bailey, Thomas Ruschak,
- * Ken Stevens, Steve McClure
+ * Copyright (C) 1994-2014, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ * Ken Stevens, Steve McClure, Markus Armbruster
* Copyright (C) 1991-3 Stephen Crane
*
- * This program is free software; you can redistribute it and/or modify
+ * Empire is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
+ * the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* ---
*
* ---
*
* rwlock.c: Read-write locks
- *
+ *
* Known contributors to this file:
* Ron Koenderink, 2007
- * Markus Armbruster, 2007
+ * Markus Armbruster, 2007-2009
*/
#include <config.h>
lwp_rwlock_unlock(struct lwp_rwlock *rwlock)
{
struct lwpProc *p;
+ int maxpri;
lwpStatus(LwpCurrent, "unlocking rwlock %s", rwlock->name);
if (CANT_HAPPEN(rwlock->count == 0))
if (rwlock->count == 0 && rwlock->wq.head) {
p = lwpGetFirst(&rwlock->wq);
lwpStatus(p, "wake up next writer of rwlock %s", rwlock->name);
+ maxpri = p->pri;
+ lwpReady(p);
} else if (rwlock->count >= 0 && rwlock->rq.head && !rwlock->wq.head) {
- p = lwpGetFirst(&rwlock->rq);
- lwpStatus(p, "wake up next reader of rwlock %s", rwlock->name);
+ maxpri = 0;
+ while ((p = lwpGetFirst(&rwlock->rq))) {
+ lwpStatus(p, "wake up next reader of rwlock %s", rwlock->name);
+ maxpri = MAX(maxpri, p->pri);
+ lwpReady(p);
+ }
} else
return;
- lwpReady(p);
- if (LwpCurrent->pri < p->pri) {
+ if (LwpCurrent->pri < maxpri) {
lwpStatus(LwpCurrent, "yielding to thread with higher priority");
lwpYield();
}