Re: Hibernation out-of-memory problem.

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Saturday 10 October 2009, Thomas Hellstrom wrote:
> Hi!
> 
> I'm trying to port a graphics DRM device driver over to the new power 
> management hooks in
> 
> struct dev_pm_ops.
> 
> During the "prepare" call, Video RAM contents may be copied either to 
> shmem objects or pages allocated using alloc_page().
> Unfortunately, this seems to lead to the hibernation process running out 
> of free pages.
> 
> One possible cause is that the function swsusp_shrink_memory() is called 
> before the prepare() call, and therefore doesn't free up enough memory.
> 
> What would be the correct way around this? Should swsusp_shrink_memory() 
> be moved to after prepare(), or is it possible to get some kind of 
> notification after user space processes is stopped, but before 
> swsusp_shrink_memory()?

There are suspend/hibernation notifiers that can be used for this purpose.

Thanks,
Rafael