Date: Sat, 22 Mar 2014 11:01:52 -0700 From: John-Mark Gurney <jmg@funkthat.com> To: Ian Lepore <ian@FreeBSD.org> Cc: svn-src-head@FreeBSD.org, svn-src-all@FreeBSD.org, Ruslan Bukin <br@FreeBSD.org>, src-committers@FreeBSD.org, Andrew Turner <andrew@fubar.geek.nz> Subject: Re: svn commit: r263424 - head/sys/arm/conf Message-ID: <20140322180151.GY32089@funkthat.com> In-Reply-To: <1395494755.81853.38.camel@revolution.hippie.lan> References: <201403201701.s2KH1L84024044@svn.freebsd.org> <20140321094316.76ccf459@bender.Home> <1395412070.81853.8.camel@revolution.hippie.lan> <20140321190402.GT32089@funkthat.com> <1395494755.81853.38.camel@revolution.hippie.lan>
next in thread | previous in thread | raw e-mail | index | archive | help
Ian Lepore wrote this message on Sat, Mar 22, 2014 at 07:25 -0600: > On Fri, 2014-03-21 at 12:04 -0700, John-Mark Gurney wrote: > > Ian Lepore wrote this message on Fri, Mar 21, 2014 at 08:27 -0600: > > > On Fri, 2014-03-21 at 09:43 +0000, Andrew Turner wrote: > > > > On Thu, 20 Mar 2014 17:01:21 +0000 (UTC) > > > > Ruslan Bukin <br@FreeBSD.org> wrote: > > > > > > > > > Author: br > > > > > Date: Thu Mar 20 17:01:21 2014 > > > > > New Revision: 263424 > > > > > URL: http://svnweb.freebsd.org/changeset/base/263424 > > > > > > > > > > Log: > > > > > Disable debugging by default. > > > > > > > > I don't like this on head. I have found a number of issues that were > > > > hidden because the kernel config most people were using for development > > > > had WITNESS, INVARIANTS and DIAGNOSTIC disabled. > > > > I agree... HEAD needs these to make sure they are production ready... > > > > > I disagree. Witness is essentially useless anymore, because there are > > > so many known LORs that nobody cares about when you report them that all > > > it does is spews noise. Maybe it's useful when you're looking for a > > > particular problem, but leaving it on all the time has just lost its > > > value. > > > > I wouldn't be tracking down an AVILA bug if it wasn't for INVARIANTS.. > > > > Also, your complaint is solely about WITNESS not the other ones... > > > > Considering how many people are writing new drivers for ARM, and might > > be introducing locking issues w/ those new drivers, WITNESS should be > > included, plus, if you disable INVARIANTS, it means that all the > > lock assert functions will be turned off, and we might miss an odd > > calling stack which doesn't hold a lock or something... > > > > If you're using HEAD for performance, it's easy to turn these off.. > > > > My complaint is only about witness. echo debug.witness.watch=0 >> /etc/sysctl.conf :) Not as fast as completely turning it off, but almost there.. > But... about being easy to turn off... how do they get turned off on > non-head branches? Does re@ really have to go grovel through 77 config > files turning off diagnostic options? Do we have to handle that > difference when merging things to stable branches? Apparently they do: https://svnweb.freebsd.org/base?view=revision&revision=256283 Though, handling merging is an issue for all arches... possibly more anoying for ARM since it's so actively developed... > Last time I tried to put something into arm/conf/DEFAULTS I got my hand > slapped, but... putting the diagnostic options in there on head and not > on stable branches would make the "touch 77 config files" problem go > away. Yes, I agree this is a problem and needs a solution, and I do agree DEFAULTS would be a resonable place, but since there are others that feel more strongly about what goes in DEFAULTS, they should speak about it.. -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20140322180151.GY32089>