On Thu, 2013-04-25 at 08:58 +1000, Dave Chinner wrote:
> On Wed, Apr 24, 2013 at 01:39:52PM -0500, Chandra Seetharaman wrote:
> > Hi Dave,
> > Since this solution is for production environment, would it be valuable
> > to have a sysctl variable to allow enabling/disabling XFS_WARN, as
> > opposed to needing to recompile the module afresh ?
> The idea is that distros enable it on the debug kernel packages
> rather than using CONFIG_XFS_DEBUG=y. Hence if someone has a
> problem, they just install the debug kernel and they get all this
> additional checking.
Thanks for the clarification.
I was thinking that CONFIG_XFS_DEBUG would be enabled in the distro's
debug kernel and this new option is in addition to that. Hence, my
So, with this new config option, CONFIG_XFS_DEBUG will only be used in
development environment, correct ?
> There are roughly 1700 ASSERT statements in the XFS code, so
> compiling them in unconditionally is a lot of extra code. Adding a
> sysctl to make them conditional adds as many branches into the code
> than in 99.99999% of calls are never going to evaluate as true. The
> convenience of a sysctl is more than outweighed by the additional
> overhead for the majortiy of people that don't need to diagnose
> problems on their system.
> Hence I don't think the overhead of unconditionally compiling in
> ASSERT checks is worth while for the majority of users, especially
> as most distros ship a debug kernel for exactly this purpose....