Re: [PATCH 1/2] r8169: allocate with GFP_KERNEL flag when able to sleep

Stanislaw Gruszka
2010-10-08T14:50:59Z

On Fri, Oct 08, 2010 at 04:25:00PM +0200, Stanislaw Gruszka wrote:
> We have fedora bug report where driver fail to initialize after
> suspend/resume because of memory allocation errors:
> https://bugzilla.redhat.com/show_bug.cgi?id=629158

There is also one more thing to do regarding above. Calltraces from bug
reports, shows that order 3 allocation fail. On arch with 4kB pages,
order 3 mean 32kB allocation. We want to alloc 16kB, but there is also
internal sk_buff data what make that we exceed the boundary and take
32kB from allocator, getting almost 50% wastage.

To fix we can use similar method as in niu or iwlwifi drivers, alloc
pages directly form buddy allocator and attach them to skb (by
skb_add_rx_frag for example). I'm going to prepare such patch, but
I have one doubt, what happens if page size in system is bigger
than 16kB, should I care about such case?

Stanislaw