From owner-svn-src-user@FreeBSD.ORG  Mon May  9 07:03:01 2011
Return-Path: <owner-svn-src-user@FreeBSD.ORG>
Delivered-To: svn-src-user@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id E15DC1065673;
	Mon,  9 May 2011 07:03:01 +0000 (UTC) (envelope-from avg@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id D3FC18FC12;
	Mon,  9 May 2011 07:03:01 +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 p497315D080273;
	Mon, 9 May 2011 07:03:01 GMT (envelope-from avg@svn.freebsd.org)
Received: (from avg@localhost)
	by svn.freebsd.org (8.14.4/8.14.4/Submit) id p49731wY080271;
	Mon, 9 May 2011 07:03:01 GMT (envelope-from avg@svn.freebsd.org)
Message-Id: <201105090703.p49731wY080271@svn.freebsd.org>
From: Andriy Gapon <avg@FreeBSD.org>
Date: Mon, 9 May 2011 07:03:01 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-user@freebsd.org
X-SVN-Group: user
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r221675 - user/avg/xcpu/sys/sys
X-BeenThere: svn-src-user@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "SVN commit messages for the experimental &quot; user&quot;
	src tree" <svn-src-user.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-user>,
	<mailto:svn-src-user-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-user>
List-Post: <mailto:svn-src-user@freebsd.org>
List-Help: <mailto:svn-src-user-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-user>,
	<mailto:svn-src-user-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 09 May 2011 07:03:02 -0000

Author: avg
Date: Mon May  9 07:03:01 2011
New Revision: 221675
URL: http://svn.freebsd.org/changeset/base/221675

Log:
  add a macro to identify a panic thread
  
  the macro is placed into systm.h as all potential users of this macro
  should already include this header file

Modified:
  user/avg/xcpu/sys/sys/systm.h

Modified: user/avg/xcpu/sys/sys/systm.h
==============================================================================
--- user/avg/xcpu/sys/sys/systm.h	Mon May  9 07:01:19 2011	(r221674)
+++ user/avg/xcpu/sys/sys/systm.h	Mon May  9 07:03:01 2011	(r221675)
@@ -109,6 +109,15 @@ enum VM_GUEST { VM_GUEST_NO = 0, VM_GUES
 	    ((uintptr_t)&(var) & (sizeof(void *) - 1)) == 0, msg)
 
 /*
+ * If we have already panic'd and this is the thread that called
+ * panic(), then don't block on any mutexes but silently succeed.
+ * Otherwise, the kernel will deadlock since the scheduler isn't
+ * going to run the thread that holds the lock we need.
+ */
+#define	IS_PANIC_THREAD()	\
+	(panicstr != NULL && (curthread->td_flags & TDF_INPANIC) != 0)
+
+/*
  * XXX the hints declarations are even more misplaced than most declarations
  * in this file, since they are needed in one file (per arch) and only used
  * in two files.