From owner-svn-src-stable@FreeBSD.ORG  Thu Dec 17 02:06:07 2009
Return-Path: <owner-svn-src-stable@FreeBSD.ORG>
Delivered-To: svn-src-stable@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 9FAE51065676;
	Thu, 17 Dec 2009 02:06:07 +0000 (UTC)
	(envelope-from marcel@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id 8E21C8FC0A;
	Thu, 17 Dec 2009 02:06:07 +0000 (UTC)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id nBH267EN017401;
	Thu, 17 Dec 2009 02:06:07 GMT (envelope-from marcel@svn.freebsd.org)
Received: (from marcel@localhost)
	by svn.freebsd.org (8.14.3/8.14.3/Submit) id nBH267ma017399;
	Thu, 17 Dec 2009 02:06:07 GMT (envelope-from marcel@svn.freebsd.org)
Message-Id: <200912170206.nBH267ma017399@svn.freebsd.org>
From: Marcel Moolenaar <marcel@FreeBSD.org>
Date: Thu, 17 Dec 2009 02:06:07 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-stable@freebsd.org, svn-src-stable-8@freebsd.org
X-SVN-Group: stable-8
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r200622 - stable/8/lib/libthr/thread
X-BeenThere: svn-src-stable@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: SVN commit messages for all the -stable branches of the src tree
	<svn-src-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-stable>, 
	<mailto:svn-src-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-stable>
List-Post: <mailto:svn-src-stable@freebsd.org>
List-Help: <mailto:svn-src-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-stable>,
	<mailto:svn-src-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 17 Dec 2009 02:06:07 -0000

Author: marcel
Date: Thu Dec 17 02:06:07 2009
New Revision: 200622
URL: http://svn.freebsd.org/changeset/base/200622

Log:
  MFC rev 200498:
  Work-around a race condition on ia64 while unlocking a contested lock.

Modified:
  stable/8/lib/libthr/thread/thr_umtx.c
Directory Properties:
  stable/8/lib/libthr/   (props changed)

Modified: stable/8/lib/libthr/thread/thr_umtx.c
==============================================================================
--- stable/8/lib/libthr/thread/thr_umtx.c	Thu Dec 17 00:22:56 2009	(r200621)
+++ stable/8/lib/libthr/thread/thr_umtx.c	Thu Dec 17 02:06:07 2009	(r200622)
@@ -112,10 +112,13 @@ __thr_umutex_timedlock(struct umutex *mt
 int
 __thr_umutex_unlock(struct umutex *mtx, uint32_t id)
 {
+#ifndef __ia64__
+	/* XXX this logic has a race-condition on ia64. */
 	if ((mtx->m_flags & (UMUTEX_PRIO_PROTECT | UMUTEX_PRIO_INHERIT)) == 0) {
 		atomic_cmpset_rel_32(&mtx->m_owner, id | UMUTEX_CONTESTED, UMUTEX_CONTESTED);
 		return _umtx_op_err(mtx, UMTX_OP_MUTEX_WAKE, 0, 0, 0);
 	}
+#endif /* __ia64__ */
 	return _umtx_op_err(mtx, UMTX_OP_MUTEX_UNLOCK, 0, 0, 0);
 }