From owner-svn-src-all@FreeBSD.ORG  Thu Aug 27 00:45:01 2009
Return-Path: <owner-svn-src-all@FreeBSD.ORG>
Delivered-To: svn-src-all@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id B3D1F106568C;
	Thu, 27 Aug 2009 00:45:01 +0000 (UTC)
	(envelope-from attilio@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id 9BE0A8FC20;
	Thu, 27 Aug 2009 00:45:01 +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 n7R0j1UV079839;
	Thu, 27 Aug 2009 00:45:01 GMT (envelope-from attilio@svn.freebsd.org)
Received: (from attilio@localhost)
	by svn.freebsd.org (8.14.3/8.14.3/Submit) id n7R0j1xs079837;
	Thu, 27 Aug 2009 00:45:01 GMT (envelope-from attilio@svn.freebsd.org)
Message-Id: <200908270045.n7R0j1xs079837@svn.freebsd.org>
From: Attilio Rao <attilio@FreeBSD.org>
Date: Thu, 27 Aug 2009 00:45:01 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-stable@freebsd.org, svn-src-stable-7@freebsd.org
X-SVN-Group: stable-7
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r196574 - stable/7/sys/kern
X-BeenThere: svn-src-all@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "SVN commit messages for the entire src tree \(except for &quot;
	user&quot; and &quot; projects&quot; \)" <svn-src-all.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-all>
List-Post: <mailto:svn-src-all@freebsd.org>
List-Help: <mailto:svn-src-all-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 27 Aug 2009 00:45:01 -0000

Author: attilio
Date: Thu Aug 27 00:45:00 2009
New Revision: 196574
URL: http://svn.freebsd.org/changeset/base/196574

Log:
  Fix a problem introduced when MFCing the rw_try_wlock() operation from
  HEAD:
  __rw_wunlock() relies on the cookie state to not be cleanly 'tid' when
  some conditions needing of special care happens, and lock recursion is
  among those.  Dirty the cookie by adding the RW_LOCK_RECURSE flag in the
  case of a successfull try lock operation.
  
  This is not a problem on -CURRENT and STABLE_8 where the unlocking
  algorithm works differently.
  
  Submitted by:	Andrew Brampton <brampton plus freebsd at gmail dot com>

Modified:
  stable/7/sys/kern/kern_rwlock.c

Modified: stable/7/sys/kern/kern_rwlock.c
==============================================================================
--- stable/7/sys/kern/kern_rwlock.c	Wed Aug 26 22:51:14 2009	(r196573)
+++ stable/7/sys/kern/kern_rwlock.c	Thu Aug 27 00:45:00 2009	(r196574)
@@ -204,6 +204,7 @@ _rw_try_wlock(struct rwlock *rw, const c
 
 	if (rw_wlocked(rw) && (rw->lock_object.lo_flags & RW_RECURSE) != 0) {
 		rw->rw_recurse++;
+		atomic_set_ptr(&rw->rw_lock, RW_LOCK_RECURSED);
 		rval = 1;
 	} else
 		rval = atomic_cmpset_acq_ptr(&rw->rw_lock, RW_UNLOCKED,