Hi Christoph, On Wed, Aug 14, 2013 at 04:36:44PM +0000, Christoph Lameter wrote: > On Wed, 14 Aug 2013, Minchan Kim wrote: > > > On Tue, Aug 13, 2013 at 04:21:30PM +0000, Christoph Lameter wrote: > > > On Tue, 13 Aug 2013, Minchan Kim wrote: > > > > > > > VM sometime want to migrate and/or reclaim pages for CMA, memory-hotplug, > > > > THP and so on but at the moment, it could handle only userspace pages > > > > so if above example subsystem have pinned a some page in a range VM want > > > > to migrate, migration is failed so above exmaple couldn't work well. > > > > > > Dont we have the mmu_notifiers that could help in that case? You could get > > > a callback which could prepare the pages for migration? > > > > Now I'm not familiar with mmu_notifier so please could you elaborate it > > a bit for me to dive into that? > > Add a notifier callback for unpinning pages to the mmu notifier subsystem > and then your drivers could register with the subsystem to get > notifications when migration needs to occur etc. > When I look API of mmu_notifier, it has mm_struct so I guess it works for only user process. Right? If so, I need to register it without user conext because zram, zswap and zcache works for only kernel side. -- Kind regards, Minchan Kim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>