[dm-devel] Re: [PATCH 2.6.19 5/5] fs: freeze_bdev with semaphore not mutex

[Pavel Machek]

Hi!

> > > OTOH I have no idea _how_ we can tell xfs that the processes have been
> > > frozen.  Should we introduce a global flag for that or something?
> > 
> > I guess XFS should just do all the writes from process context, and
> > refuse any writing when its threads are frozen... I actually still
> > believe it is doing the right thing, because you can't really write to
> > disk from timer.
> 
> This is from a work queue, so in fact from a process context, but from
> a process that is running with PF_NOFREEZE.

Why not simply &~ PF_NOFREEZE on that particular process? Filesystems
are free to use threads/work queues/whatever, but refrigerator should
mean "no writes to filesystem" for them...

									Pavel
-- 
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