lkml.org 
[lkml]   [2010]   [Mar]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [linux-pm] Is it supposed to be ok to call del_gendisk while userspace is frozen?
On Mon, 1 Mar 2010, Pavel Machek wrote:

> Hi!
>
> > > > This is a matter for Jens. Is the bdi writeback task freezable? If it
> > > > is, should it be made unfreezable?
> > >
> > > I'm not a big expect on what tasks should be freezable or not. As it
> > > stands, the writeback tasks will attempt to freeze and thaw with the
> > > system. I guess that screws the sync from resume call, since it's not
> > > running and the sync will wait for it to retrieve and finish that work
> > > item.
> > >
> > > To the suspend experts - can we safely mark the writeback tasks as
> > > non-freezable?
> >
> > The reason for freezing those tasks is to avoid writebacks at random
> > times during a system sleep transition, when the underlying device may
> > already be suspended, right?
>
> It is also there to avoid inconsistency between in-filesystem data and
> snapshot in hibernation image.

A good point, although in this case I think it won't matter. Writing
out a dirty page twice (once right after taking the snapshot and then
again after resuming from hibernation) will leave the disk in a correct
state.

Alan Stern



\
 
 \ /
  Last update: 2010-03-01 16:25    [W:0.245 / U:0.116 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site