From owner-svn-src-all@FreeBSD.ORG  Thu Jun 23 16:34:42 2011
Return-Path: <owner-svn-src-all@FreeBSD.ORG>
Delivered-To: svn-src-all@freebsd.org
Received: from mx1.freebsd.org (unknown [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 4A3FD106564A;
	Thu, 23 Jun 2011 16:34:42 +0000 (UTC)
	(envelope-from nwhitehorn@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [69.147.83.44])
	by mx1.freebsd.org (Postfix) with ESMTP id 39FCB8FC16;
	Thu, 23 Jun 2011 16:34:42 +0000 (UTC)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.4/8.14.4) with ESMTP id p5NGYgEn007390;
	Thu, 23 Jun 2011 16:34:42 GMT
	(envelope-from nwhitehorn@svn.freebsd.org)
Received: (from nwhitehorn@localhost)
	by svn.freebsd.org (8.14.4/8.14.4/Submit) id p5NGYgTV007387;
	Thu, 23 Jun 2011 16:34:42 GMT
	(envelope-from nwhitehorn@svn.freebsd.org)
Message-Id: <201106231634.p5NGYgTV007387@svn.freebsd.org>
From: Nathan Whitehorn <nwhitehorn@FreeBSD.org>
Date: Thu, 23 Jun 2011 16:34:42 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-head@freebsd.org
X-SVN-Group: head
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r223479 - head/sys/powerpc/aim
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, 23 Jun 2011 16:34:42 -0000

Author: nwhitehorn
Date: Thu Jun 23 16:34:41 2011
New Revision: 223479
URL: http://svn.freebsd.org/changeset/base/223479

Log:
  Clear any outstanding atomic reservations when traps are taken. This fixes
  some interesting bugs (mostly on SMP systems) with atomic operations
  silently failing in interrupt heavy situations, especially when using
  overflow pages.

Modified:
  head/sys/powerpc/aim/trap_subr32.S
  head/sys/powerpc/aim/trap_subr64.S

Modified: head/sys/powerpc/aim/trap_subr32.S
==============================================================================
--- head/sys/powerpc/aim/trap_subr32.S	Thu Jun 23 16:21:43 2011	(r223478)
+++ head/sys/powerpc/aim/trap_subr32.S	Thu Jun 23 16:34:41 2011	(r223479)
@@ -748,6 +748,8 @@ k_trap:
 /* Call C interrupt dispatcher: */
 trapagain:
 	addi	%r3,%r1,8
+	addi	%r4,%r1,-4		/* Clear any existing reservations */
+	stwcx.	%r3,0,%r4		
 	bl	CNAME(powerpc_interrupt)
 	.globl	CNAME(trapexit)		/* backtrace code sentinel */
 CNAME(trapexit):

Modified: head/sys/powerpc/aim/trap_subr64.S
==============================================================================
--- head/sys/powerpc/aim/trap_subr64.S	Thu Jun 23 16:21:43 2011	(r223478)
+++ head/sys/powerpc/aim/trap_subr64.S	Thu Jun 23 16:34:41 2011	(r223479)
@@ -508,6 +508,8 @@ trapagain:
 	lis	%r3,tocbase@ha
 	ld	%r2,tocbase@l(%r3)
 	addi	%r3,%r1,48
+	addi	%r4,%r1,-8		/* Clear any existing reservations */
+	stdcx.	%r3,0,%r4		
 	bl	CNAME(powerpc_interrupt)
 	nop