svn commit: r272032 - head/sys/conf

[Konstantin Belousov]

On Tue, Sep 23, 2014 at 05:04:21PM +0000, Bryan Drewery wrote:
> Author: bdrewery
> Date: Tue Sep 23 17:04:21 2014
> New Revision: 272032
> URL: http://svnweb.freebsd.org/changeset/base/272032
> 
> Log:
>   DEBUG_LOCKS no longer modifies 'struct vnode', nor does fstat(1) use it.
>   fstat(1) now uses libprocstat(9).  There is no userland impact to using this.

DEBUG_VFS_LOCKS does modify KBI of VFS, by adding struct stack to
lockmgr, and lockmgr is embedded into each struct vnode.

VFS modules, in particular, filesystems, compiled for mismatched
kernel WRT DEBUG_VFS_LOCKS, would cause strange breakage.

>   
>   MFC after:	3 days
> 
> Modified:
>   head/sys/conf/NOTES
> 
> Modified: head/sys/conf/NOTES
> ==============================================================================
> --- head/sys/conf/NOTES	Tue Sep 23 16:06:28 2014	(r272031)
> +++ head/sys/conf/NOTES	Tue Sep 23 17:04:21 2014	(r272032)
> @@ -2625,9 +2625,7 @@ options 	NSFBUFS=1024
>  # Enable extra debugging code for locks.  This stores the filename and
>  # line of whatever acquired the lock in the lock itself, and changes a
>  # number of function calls to pass around the relevant data.  This is
> -# not at all useful unless you are debugging lock code.  Also note
> -# that it is likely to break e.g. fstat(1) unless you recompile your
> -# userland with -DDEBUG_LOCKS as well.
> +# not at all useful unless you are debugging lock code.
>  #
>  options 	DEBUG_LOCKS
>