| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Mon, 11 Feb 2008 11:38:32 -0500 From: Jason Baron <jbaron@...hat.com> To: Jan Engelhardt <jengelh@...putergmbh.de> Cc: Joe Perches <joe@...ches.com>, mathieu.desnoyers@...ymtl.ca, akpm@...ux-foundation.org, mingo@...e.hu, fche@...hat.com, linux-kernel@...r.kernel.org Subject: Re: [patch 0/4] make pr_debug() dynamic On Sat, Feb 09, 2008 at 11:21:58PM +0100, Jan Engelhardt wrote: > >> > >> What's wrong with klogd -c 8 or equivalent? > > > >Setting the loglevel higher, will not make pr_debug() calls visible. The only > >way to make them visible right now, is by re-compiling the kernel. > > pr_debug() was IMHO meant to be a compile-time optimization > to throw out debug messages most people do not want. > > If you want to switch on/off debugging messages, use > printk(KERN_DEBUG) [with klogd -c something] and not pr_debug! true, we could turn pr_debug() calls into printk(KERN_DEBUG) calls, but there is an overhead to all these extra printk functions calls. The way I have implemented pr_debug(), there is no function call at all, in the off case. To me pr_debug() is currently a compile option, b/c there is often a lot of overhead to having it on. Being able to turn pr_debug() calls off/on in a production environment, to get debugging data seems very valuable. thanks, -Jason -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists