Re: [PATCH] Page writeback broken after resume: wb_timer lost

[Pavel Machek <pavel@ucw.cz>]

Hi!

> Well that's a crock, isn't it?
> 
> 
> Peter, does this fix it?
> 
> 
> From: Andrew Morton <akpm@osdl.org>
> 
> pdflush is carefully designed to ensure that all wakeups have some
> corresponding work to do - if a woken-up pdflush thread discovers that it
> hasn't been given any work to do then this is considered an error.
> 
> That all broke when swsusp came along - because a timer-delivered wakeup to a
> frozen pdflush thread will just get lost.  This causes the pdflush thread to
> get lost as well: the writeback timer is supposed to be re-armed by pdflush in
> process context, but pdflush doesn't execute the callout which does this.
> 
> Fix that up by ignoring the return value from try_to_freeze(): jsut proceed,
> see if we have any work pending and only go back to sleep if that is not the
> case.

Looks okay to me.

							Pavel
	(who wonders what are the other places where we have similar
	problems)
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html