From owner-freebsd-current@FreeBSD.ORG Fri Dec 2 15:41:54 2011 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E273E1065670; Fri, 2 Dec 2011 15:41:54 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id B83CB8FC15; Fri, 2 Dec 2011 15:41:54 +0000 (UTC) Received: from bigwig.baldwin.cx (bigwig.baldwin.cx [96.47.65.170]) by cyrus.watson.org (Postfix) with ESMTPSA id 6D8B046B09; Fri, 2 Dec 2011 10:41:54 -0500 (EST) Received: from John-Baldwins-MacBook-Air.local (c-68-36-150-83.hsd1.nj.comcast.net [68.36.150.83]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id D8A2CB91E; Fri, 2 Dec 2011 10:41:53 -0500 (EST) Message-ID: <4ED8F1C1.7010206@FreeBSD.org> Date: Fri, 02 Dec 2011 10:41:53 -0500 From: John Baldwin User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:8.0) Gecko/20111105 Thunderbird/8.0 MIME-Version: 1.0 To: Andriy Gapon References: <20111113083215.GV50300@deviant.kiev.zoral.com.ua> <201112011349.50502.jhb@freebsd.org> <4ED7E6B0.30400@FreeBSD.org> <201112011553.34432.jhb@freebsd.org> <4ED7F4BC.3080206@FreeBSD.org> <4ED855E6.20207@FreeBSD.org> <4ED8A306.9020801@FreeBSD.org> In-Reply-To: <4ED8A306.9020801@FreeBSD.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Fri, 02 Dec 2011 10:41:54 -0500 (EST) Cc: freebsd-current@FreeBSD.org Subject: Re: Stop scheduler on panic X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Dec 2011 15:41:55 -0000 On 12/2/11 5:05 AM, Andriy Gapon wrote: > on 02/12/2011 06:36 John Baldwin said the following: >> Ah, ok (I had thought SCHEDULER_STOPPED was going to always be true when kdb was >> active). But I think these two changes should cover critical_exit() ok. >> > > I attempted to start a discussion about this a few times already :-) > Should we treat kdb context the same as SCHEDULER_STOPPED context (in the > current definition) ? That is, skip all locks in the same fashion? > There are pros and contras. kdb should not block on locks, no. Most debugger commands should not go near locks anyway unless they are intended to carefully modify the existing system in a safe manner (such as the 'kill' command which should only be using try locks and fail if it cannot safely post the signal). -- John Baldwin