From mboxrd@z Thu Jan 1 00:00:00 1970 From: George Dunlap Subject: Re: [PATCH] PoD: Check p2m assumption in debug builds Date: Thu, 17 Sep 2009 10:43:09 +0100 Message-ID: <4AB204AD.30201@eu.citrix.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: "xen-devel@lists.xensource.com" , Kouya Shimura List-Id: xen-devel@lists.xenproject.org Keir Fraser wrote: > On 17/09/2009 02:26, "Kouya Shimura" wrote: > > >> real 0m2.343s >> user 0m0.040s >> sys 0m0.030s >> >> real 2m25.741s >> user 0m0.090s >> sys 0m0.020s >> >> I'm about to lose my patience with it. :-) >> Can you control it by a boot parameter? (ex. "pod_debug=nnn") >> > > Yeah, that's too slow for our normal debug build. I think we'll revert the > patch -- noone would ever enable it, unless maybe if helping George track > down a PoD bug. > Hmm... my only concern is that the assumption seems like something which might easily change, with no one realizing that they'd broken the assumption, and the codepath not being tested since most OSS users probably won't be using PoD. Hmm, perhaps we could wrap it with an if() statement checking if there are any outstanding PoD entries? The assumption only really matters when PoD is in use. Alternately, a separate #define for PoD debug might be useful, so we can easily turn on all these options when we need to. -George