Re: [PATCH v10]: Hibernation: fix the number of pages used for hibernate/thaw buffering

[Per Olofsson <pelle@debian.org>]

2012-04-12 13:31, Bojan Smojver skrev:
> Bojan Smojver <bojan@rexursive.com> wrote:
> 
>> -	read_pages = (nr_free_pages() - snapshot_get_image_size()) >> 1; 
>> +	read_pages = (low_free_pages() - snapshot_get_image_size()) / 2;
> 
> Actually, I am pretty sure this part of the patch is wrong. Image can
> be bigger than the size of non-high memory. So, this calculation may
> turn up entirely bogus numbers, given we are dealing with unsigned
> values. Sure, we clamp that a line later, so all is not lost, but
> still, it needs to be fixed.

Indeed. I think what you want is:

read_pages = min(low_free_pages(),
                 nr_free_pages() - snapshot_get_image_size()) / 2;

-- 
Pelle