Re: 2.6.34 echo j > /proc/sysrq-trigger causes inifnite unfreeze/Thaw event

[Josef Bacik <josef@redhat.com>]

On Tue, Jun 08, 2010 at 10:58:52PM +1000, Dave Chinner wrote:
> On Tue, Jun 08, 2010 at 12:26:52PM +1000, Dave Chinner wrote:
> > On Mon, Jun 07, 2010 at 10:07:41PM -0400, Josef Bacik wrote:
> > > Well damnit.  I guess what we need to do is get rid of the freeze_bdev/thaw_bdev
> > > interface altogether, and move the count stuff down to the super.  Anybody who
> > > calls freeze_bdev/thaw_bdev knows the sb anyway, so if we get rid of
> > > bd_fsfreeze_count and move it to sb->s_fsfreeze_count and do the same with
> > > bd_fsfreeze_mutex then we could solve this altogether and simplify the
> > > interface.  It grows the sb struct, but hey it shrinks the bdev struct :).  How
> > > horrible of an idea is that?  Thanks,
> > 
> > Kind of what I was thinking of. I wasn't sure about what btrfs
> > required, but you've cleared that up. I'll put a patch together and
> > see how it looks.
> 
> Not too bad:
> 
>  8 files changed, 137 insertions(+), 190 deletions(-)
> 
> It really needs to be split up into multiple commits and the test
> case needs to exercise dmsetup suspend/resume as well, but I think
> this works well enough for comments at this point. I've only tested
> it on XFS so far.
> 

I like it.  Everything seems in order, course now I realize that dm trying to
freeze a bdev with btrfs on it will not work, but thats a seperate, horrible
situation that can wait till later :).  Thanks,

Josef